**Venous Thromboembolism and Bleeding after Transurethral Resection of the Prostate (TURP) in Patients with Preoperative Antithrombotic Therapy: A Single-Center Study from a Tertiary Hospital in China**

**Zhongyi Li 1, Zhihuan Zheng 1, Xuesong Liu 1, Quan Zhu 1, Kaixuan Li 1, Li Huang 2, Zhao Wang 1,\*,† and Zhengyan Tang 1,\*,†**

	- **\*** Correspondence: xywangz07@163.com (Z.W.); xytzyan@163.com (Z.T.)

† These authors contributed equally to this work.

**Abstract:** Background: Venous thromboembolism (VTE) and postoperative hemorrhage are unavoidable complications of transurethral resection of the prostate (TURP). At present, more and more patients with benign prostate hyperplasia (BPH) need long-term antithrombotic therapy before operation due to cardiovascular diseases or cerebrovascular diseases. The purpose of this study was to investigate the effect of preoperative antithrombotic therapy history on lower extremity VTE and bleeding after TURP. Methods: Patients who underwent TURP in the Department of Urology, Xiangya Hospital, Central South University, from January 2017 to December 2021 and took antithrombotic drugs before operation were retrospectively analyzed. The baseline data of patients were collected, including age, prostate volume, preoperative International Prostate Symptom Score (IPSS), complications, surgical history within one month, indications of preoperative antithrombotic drugs, drug types, medication duration, etc. Main outcome measures included venous thromboembolism after TURP, intraoperative and postoperative bleeding, and perioperative blood transfusion. Secondary outcome measures included operation duration and postoperative hospitalization days, the duration of stopping antithrombotic drugs before operation, the recovery time of antithrombotic drugs after operation, the condition of lower limbs within 3 months after operation, major adverse cardiac events (MACEs), and cerebrovascular complications and death. Results: A total of 31 patients after TURP with a long preoperative history of antithrombotic drugs were included in this study. Six patients (19.4%) developed superficial venous thrombosis (SVT) postoperatively. Four of these patients progressed to deep vein thrombosis (DVT) without pulmonary thromboembolism (PE). Only one patient underwent extra bladder irrigation due to blockage of their urinary catheter by a blood clot postoperatively. The symptoms of hematuria mostly disappeared within one month postoperatively and lasted for up to three months postoperatively. No blood transfusion, surgical intervention to stop bleeding, lower limb discomfort such as swelling, MACEs, cerebrovascular complications, or death occurred in all patients within three months after surgery. Conclusion: Short-term preoperative discontinuation may help patients with antithrombotic therapy to obtain a relatively safe opportunity for TURP surgery after professional evaluation of perioperative conditions. The risks of perioperative bleeding, VTE, and serious cardiovascular and cerebrovascular complications are relatively controllable. It is essential for urologists to pay more attention to the perioperative management of these patients. However, further high-quality research results are needed for more powerful verification.

**Keywords:** antithrombotic therapy; transurethral resection of the prostate; postoperative hemorrhage; venous thromboembolism

**Citation:** Li, Z.; Zheng, Z.; Liu, X.; Zhu, Q.; Li, K.; Huang, L.; Wang, Z.; Tang, Z. Venous Thromboembolism and Bleeding after Transurethral Resection of the Prostate (TURP) in Patients with Preoperative Antithrombotic Therapy: A Single-Center Study from a Tertiary Hospital in China. *J. Clin. Med.* **2023**, *12*, 417. https://doi.org/10.3390/ jcm12020417

Academic Editor: Bhaskar K Somani

Received: 22 November 2022 Revised: 29 December 2022 Accepted: 30 December 2022 Published: 4 January 2023

**Copyright:** © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

#### **1. Introduction**

Benign prostate hyperplasia (BPH) is a common urinary system disease in elderly men which greatly affects the quality of life for these patients. The clinical manifestations are mainly lower urinary tract symptoms (LUTS) such as frequent micturition, urgency, increased nocturia, weak micturition, incomplete urination, etc. Transurethral resection of the prostate (TURP) is the main surgical method for BPH patients, and its risks include postoperative bleeding and venous thromboembolism (VTE) [1–4]. VTE refers to deep vein thrombosis (DVT) and pulmonary thromboembolism (PE) [5]. However, superficial venous thrombosis (SVT) is more common in clinical practice [6].

The incidence of BPH increases with age. Many elderly patients need long-term antithrombotic therapy before surgery due to cardiovascular or cerebrovascular diseases [7]. Antithrombotic therapy includes anticoagulation and antiplatelet therapy. If antithrombotic therapy is discontinued during the perioperative period, the risk of cardiovascular and cerebrovascular events will increase [8], while continuing therapy will increase the risk of bleeding after TURP [9]. A previous study showed that the history of antithrombotic drug treatment within one month was an independent risk factor for VTE after urological non-malignant tumor surgery, and the risk of VTE after surgery was markedly increased 10-fold compared to that of patients without antithrombotic drug use [10]. The timing of preoperative discontinuation of antithrombotic drugs is critical. However, the existing studies [11,12] mostly focus on the influence of stopping time on postoperative hemorrhage risk and fail to comprehensively assess the risk of hemorrhage and VTE. In addition, most studies [13–15] only analyzed the effect of aspirin on TURP surgery, which is difficult to fully adapt to the actual complex clinical situation. Therefore, the purpose of this study is to explain the occurrence of VTE and bleeding after TURP in patients who stopped using antithrombotic drugs before operation, which may provide a reference for clinical practice.

#### **2. Materials and Methods**

#### *2.1. Study Population*

This study is a retrospective study and has been approved by the Ethics Committee of Xiangya Hospital of Central South University (No. 202011183). The inclusion criteria were as follows: (1) patients who underwent TURP surgery in the Department of Urology, Xiangya Hospital, Central South University, from January 2017 to December 2021; (2) duration for maintenance antithrombotic drugs before operation of more than one month. The following were exclusion criteria: (1) patients complicated with active malignant diseases; (2) a history of prostate surgery or urinary tract reconstruction surgery; (3) postoperative pathological examination showing prostate cancer; (4) VTE detected preoperatively; (5) bridging therapy such as low-molecular-weight heparin before operation.

According to the epidemiology and clinical symptoms of BPH patients, referring to the guidelines and experts' consensus on the prevention and treatment of BPH and VTE, the clinical data we collected mainly included age, prostate volume, preoperative International Prostate Symptom Score (IPSS), complications (hypertension, coronary heart disease, diabetes, stroke, varicose veins of lower limbs, etc.), surgical history within one month, and preoperative use of antithrombotic drugs.

#### *2.2. Outcome Measures*

The main outcomes are venous thromboembolism after TURP, intraoperative and postoperative bleeding, and perioperative blood transfusion. The amount of bleeding and the duration of the operation are all referred to in the surgical anesthesia record sheet. Postoperative bleeding can be divided into whether there is slight gross hematuria (reddish) or obvious gross hematuria (crimson) within 3 months after operation and whether extra bladder irrigation or re-operation is needed. Secondary outcomes include operation duration and postoperative hospitalization days, the duration of stopping antithrombotic drugs before operation, the recovery time of antithrombotic drugs after operation, the condition of the lower limbs, major adverse cardiac events (MACEs), cerebrovascular

complications, and death within 3 months after operation. MACEs mainly mean acute myocardial infarction, cardiac arrest, severe arrhythmia, cardiac death, etc. Cerebrovascular complications mainly refer to stroke and transient ischemic attack.

#### *2.3. Perioperative Management*

In order to control the risk of perioperative bleeding, the patients who maintained antithrombotic therapy stopped taking antithrombotic drugs before TURP after evaluation and guidance by relevant specialists, and none of them used bridging therapy. After the risk of postoperative bleeding decreased, the original antithrombotic protocol was reactivated.

All patients were treated with mechanical thromboprophylaxis to prevent venous thromboembolism during the perioperative period. On the surgery day, patients were guided by specialized nurses to wear appropriate graduated compression stockings (GCS). The frequency of removing the graduated compression stockings was limited to three times a day, and the duration of removing time was limited to half an hour. Intermittent pneumatic compression (IPC) was applied after the postoperative patient returned to the ward [16].

Before and after the operation, the patients were examined by ultrasound in both lower limbs, which was performed by experienced sonographers. If a patient has postoperative symptoms such as dyspnea, syncope, hemoptysis, chest pain, shock, or decreased oxygen saturation, further examination such as pulmonary CTA and/or echocardiography is required to determine the occurrence of PE.

Once the patient was diagnosed with VTE or SVT, mechanical prevention of thrombosis (GCS and IPC) was immediately stopped according to the consultation opinion from the VTE group, and the risk of bleeding was assessed before anticoagulant therapy or even thrombolytic therapy immediately under the guidance of the VTE professional team.

#### *2.4. Follow-Up*

Follow-up was carried out at 7 days, 1 month, and 3 months after operation, mainly through outpatient service and telephone calls. The follow-up included drugs and the duration of prescription, hematuria or bleeding 3 months after surgery, lower extremity conditions, MACEs, cerebrovascular complications, and death.

#### *2.5. Statistical Analysis*

Data were analyzed using IBM SPSS 26.0 software. Quantitative data conforming to the normal distribution are expressed as mean ± standard deviation (x ± s), while those not conforming to the normal distribution are expressed as median (interquartile range). Qualitative data are expressed as cases (percentage) (n(%)).

#### **3. Result**

#### *3.1. Patients' Baseline Data*

A total of 31 patients who underwent TURP with a long history of taking antithrombotic drugs before operation (Table 1) were included in this study. The mean age of the 31 patients was 70.3 ± 6.5 years, the mean preoperative IPSS score was 20.2 ± 3.0, and the median prostate volume was 56.2 (44.9–85.6) mL. One patient (3.2%) underwent prostate biopsy within one month before TURP.

Among the 31 patients, 6 (19.4%) had coronary stent implantation, 2 (6.5%) had aortic valve replacement, 3 (9.7%) had mitral valve replacement, 2 (6.5%) had a history of myocardial infarction, 10 (32.3%) had a history of cerebral infarction, 6 (19.4%) had a history of coronary heart disease, and 2 (6.5%) had a history of atrial fibrillation. Two patients (6.5%) took long-term oral warfarin and twenty-nine patients (93.5%) took longterm oral antiplatelet drugs, including 19 patients (61.3%) taking aspirin, 6 patients (19.4%) taking clopidogrel, and 4 patients (12.9%) taking aspirin combined with clopidogrel. Three patients (9.7%) took medicine for less than one year, fifteen patients (48.4%) for 1–5 years, eleven patients (35.5%) for 5–10 years, and two patients (6.5%) for more than 10 years.


**Table 1.** Baseline information of patients and types, indications, and administration duration of antithrombotic drugs (n = 31).

#### *3.2. Incidence of VTE after TURP*

SVT after surgery occurred in 6 (19.4%) of 31 TURP patients with a history of taking antithrombotic drugs preoperatively. Among them, four patients developed DVT without PE. In the remaining 25 patients, there was no SVT/DVT/PE (Table 2).

**Table 2.** Incidence of VTE after TURP (n = 31).


#### *3.3. Perioperative Situation of TURP*

Among the 31 patients, antithrombotic drug discontinuation occurred in three cases (9.7%) within one week before surgery. In 24 cases (77.4%), the withdrawal time span was between one and two weeks, and in the other four cases (12.9%), it was more than two weeks. After preoperative drug discontinuation in 31 patients, no bridging therapy was performed and no new adverse events such as myocardial infarction and cerebral infarction occurred. The median operation duration was 75 (50–100) min, and the median intraoperative bleeding volume was 30 (10–100) mL. All patients were discharged 2–4 days after surgery, and nobody needed a blood transfusion during hospitalization (Table 3).

All patients were followed up at 7 days, 1 month, and 3 months after surgery. During the follow-up period, there was no lower extremity discomfort such as swelling, no MACEs, no cerebrovascular complications, and no death among all patients (Table 3). Two patients (6.5%) resumed antithrombotic therapy within 1 week after surgery. In 27 patients, the time for returning to antithrombotic drugs was between 1 week and 1 month after surgery. For the other two patients (6.5%), the resumption of postoperative antithrombotic regimens was delayed until 1 month later. Within 7 days after operation, reddish light hematuria was reported in 28 patients (90.3%). Crimson gross hematuria was reported in two patients, one of who was readmitted due to clot blockage of the catheter, and extra continuous bladder

irrigation was performed to keep the catheter unobstructed. Within one month, 13 patients (41.9%) occasionally had reddish light hematuria. Only one patient with hematuria finally resolved after more than three months. None of the patients needed reoperation due to bleeding (Table 4).


**Table 3.** Perioperative conditions and clinical outcomes of TURP.

**Table 4.** Hemorrhage after TURP (n (%)).


#### **4. Discussion**

BPH is a common urination disorder in middle-aged and elderly men, and it is one of the most common diseases in the clinical practice of urology around the world. Approximately 50% of men over 60 years old are troubled by BPH, and about 30% eventually need surgery [17,18]. Many elderly patients with cardiovascular and cerebrovascular diseases need long-term oral antithrombotic drugs [7]. Studies have shown that roughly 4% of patients who need TURP take anticoagulants orally for a long time [19], and a larger proportion of patients take antiplatelet drugs [20].

Hemorrhage is an unavoidable complication after TURP [21–23]. If antithrombotics are used continuously during the perioperative period, the risk of surgical hemorrhage will be enlarged considerably. However, discontinuation of antithrombotics increases the incidence of adverse cardiovascular and cerebrovascular events [24]. The European Association of Urology (EAU) recommends that the timing of preoperative discontinuation of antithrombotic drugs in non-extremely high-risk patients should be adjusted according to the type of antithrombotic drug, ranging from 12 h before surgery (e.g., for unfractionated heparin) to 5–7 days (e.g., for clopidogrel) [25]. Dimitropoulos K et al. [12] suggested that oral antithrombotic therapy should be discontinued 7–10 days before TURP in patients with low risk of cardiovascular events. There is relatively much literature in this field regarding the effect of preoperative discontinuation of antithrombotic drugs on postoperative bleeding after TURP [14,26–28]. However, these studies have mainly focused on a single drug (aspirin) and a single complication (postoperative bleeding). Our study shows that patients taking aspirin antithrombotic therapy alone account for about 60% of all antithrombotic patients, which means that 40% of patients may still be taking other antithrombotic therapies, who lack evidence-based guidance for stopping antithrombotic drugs before TURP. After detailed questioning during hospitalization and follow-up within three months after discharge, it became apparent that most of the 31 patients included in this study had been instructed to discontinue antithrombotic drugs within 7 to 14 days before surgery. Only one patient underwent bladder irrigation due to a clogged urinary catheter with blood clot postoperatively. The symptoms of hematuria lasted for 3 months at most postoperatively. No patient underwent reoperation because of hemorrhage within 3 months postoperatively. Therefore, the risk of postoperative bleeding may be acceptable if antithrombotic drugs are temporarily stopped before operation, but it is obvious that large-scale and high-level evidence is still needed to clarify this.

VTE is also a common and potentially fatal complication after operation. As the third leading cause of cardiovascular death, it has received more and more attention from clinicians in recent years [29], and it is also one of the common perioperative complications of urological surgery. However, SVT is more common in clinical practice and has always been regarded as a benign self-limiting disease. One study showed that 18.1% of SVT patients were combined with DVT and 6.9% were combined with PE [30]. Obviously, the risk of SVT cannot be ignored [31,32]. Therefore, patients who underwent TURP surgery with postoperative SVT were included in this study. A previous study pointed out that taking antithrombotic drugs for a long time will affect the balance of the anticoagulation/coagulation system of the body. The discontinuation of antithrombotic drugs before TURP may make the body become hypercoagulable in a short time, thus increasing the probability of VTE postoperatively [10]. In our study, among the 31 patients who took antithrombotic drugs for a long time, six patients (18.9%) suffered from SVT or DVT after operation, which is much higher than the incidence of VTE after TURP in the normal elderly population (0.5–1.4%) [30,33]. However, it is similar to a previous research result [34]. Taking antithrombotic drugs may be a high risk factor for VTE after TURP, and there may be two reasons. First, discontinuation of antithrombotic drugs disrupts the long-term balance of the coagulation/anticoagulation system. Second, patients with BPH are mostly old men, and it is undeniable that aging is a risk factor for VTE.

In our study, although there were no serious complications such as pulmonary embolism, myocardial infarction, and cerebral infarction under active surveillance, the incidence of postoperative VTE in patients who stopped antithrombotic drugs before operation was significantly higher than that in the normal elderly population. Therefore, in clinical practice, it is still necessary to be highly alert to the risk of postoperative VTE in patients with previous antithrombotic therapy. Urologists need to raise awareness, actively monitor, and intervene in time.

Previous studies have focused on the effect of aspirin on bleeding after TURP, but as far as we know, there is a lack of research studying the effects of preoperative antithrombotic drug discontinuation on VTE after TURP. Our research takes both of them into account and expands the antithrombotic drugs from aspirin to various commonly used antithrombotic programs in clinics as well as exploring the discontinuation program of antithrombotic drugs with acceptable risk, which is more in line with the actual clinical situation. However, this study is a retrospective observational study, and it also has certain limitations. It

cannot reveal the statistical difference in the incidence of VTE between patients treated with antithrombotic therapy and healthy elderly people, and it is not enough to draw a definite causal relationship. The sample size is also small, which may affect our analysis results. High-quality prospective multicenter studies are still needed for further analysis and confirmation in the future.

#### **5. Conclusions**

Under professional perioperative management, short-term preoperative discontinuation may help patients with antithrombotic therapy to obtain a relatively safe opportunity for TURP surgery. The risk of postoperative bleeding, VTE, and serious cardiovascular and cerebrovascular complications seems to be acceptable and controllable. It is essential for urologists to pay more attention to the perioperative management of these patients. However, this study is a single-center study with a small number of cases and thus needs further high-quality research results for more powerful verification.

**Author Contributions:** Methodology, Z.L., Z.Z., Q.Z. and Z.T.; Resources, Z.Z.; Data curation, Z.L., X.L., Q.Z., Z.W. and Z.T.; Writing—original draft, Z.L. and Z.W.; Writing—review & editing, Z.Z., K.L., L.H., Z.W. and Z.T. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was supported by the National Natural Science Foundation of China (82170706) and the Science and Technology Plan of the Department of Finance of Hunan Province (Hunan finance budget (2020) No. 09).

**Institutional Review Board Statement:** The study was conducted in accordance with the Declaration of Helsinki, and approved by the Ethics Committee of Xiangya Hospital of Central South University (No. 202011183).

**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

#### **References**


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## *Article* **Laser Efficiency and Laser Safety: Holmium YAG vs. Thulium Fiber Laser**

**Alba Sierra 1,2,3, Mariela Corrales 2,3, Bhaskar Somani <sup>4</sup> and Olivier Traxer 2,3,\***


**Abstract:** (1) Objective: To support the efficacy and safety of a range of thulium fiber laser (TFL) preset parameters for laser lithotripsy: the efficiency is compared against the Holmium:YAG (Ho:YAG) laser in the hands of juniors and experienced urologists using an in vitro ureteral model; the ureteral damage of both lasers is evaluated in an in vivo porcine model. (2) Materials and Methods: Ho:YAG laser technology and TFL technology, with a 200 μm core-diameter laser fibers in an in vitro saline ureteral model were used. Each participant performed 12 laser sessions. Each session included a 3-min lasering of stone phantoms (Begostone) with each laser technology in six different pre-settings retained from the Coloplast TFL Drive user interface pre-settings, for stone dusting: 0.5 J/10 Hz, 0.5 J/20 Hz, 0.7 J/10 Hz, 0.7 J/20 Hz, 1 J/12 Hz and 1 J/20 Hz. Both lasers were also used in three in vivo porcine models, lasering up to 20 W and 12 W in the renal pelvis and the ureter, respectively. Temperature was continuously recorded. After 3 weeks, a second look was done to verify the integrity of the ureters and kidney and an anatomopathological analysis was performed. (3) Results: Regarding laser lithotripsy efficiency, after 3 min of continuous lasering, the overall ablation rate (AR) percentage was 27% greater with the TFL technology (*p* < 0.0001). The energy per ablated mass [J/mg] was 24% lower when using the TFL (*p* < 0.0001). While junior urologists performed worse than seniors in all tests, they performed better when using the TFL than Ho:YAG technology (36% more AR and 36% fewer J/mg). In the in vivo porcine model, no urothelial damage was observed for both laser technologies, neither endoscopically during lasering, three weeks later, nor in the pathological test. (4) Conclusions: By using Coloplast TFL Drive GUI pre-set, TFL lithotripsy efficiency is higher than Ho:YAG laser, even in unexperienced hands. Concerning urothelial damage, both laser technologies with low power present no lesions.

**Keywords:** holmium YAG; thulium fiber laser; lithotripsy; laser settings; laser efficiency; laser safety; laser usability; kidney calculi; ureteroscopy

#### **1. Introduction**

Ureteroscopy with laser lithotripsy is an extended surgical intervention used for urinary stone treatment [1]. The current gold standard laser is the Holmium YAG (Ho:YAG) laser. One of the latest technologies in laser lithotripsy is the thulium fiber laser (TFL) which uses a 10–20 μm silica fiber doped with elemental thulium to generate the laser beam. When compared to Ho:YAG technology, TFL technology results are more efficient, with an ablation rate of up to three times higher and a retropulsion value that is about three times lower [2–4]. Despite the consistent technological improvement in this field, there is a lack of consensus regarding the parameters to use [5] and a need for high-level evidence when it comes to TFL vs. Ho:YAG [6,7].

On the other hand, one of the major concerns with this new technology is its safety. Some authors believe that the more efficient absorption in water (1.9 μm for TFL and

**Citation:** Sierra, A.; Corrales, M.; Somani, B.; Traxer, O. Laser Efficiency and Laser Safety: Holmium YAG vs. Thulium Fiber Laser. *J. Clin. Med.* **2023**, *12*, 149. https://doi.org/ 10.3390/jcm12010149

Academic Editors: Giacomo Novara and Javier C. Angulo

Received: 4 November 2022 Revised: 28 November 2022 Accepted: 22 December 2022 Published: 24 December 2022

**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

2.1 μm for Ho:YAG) [8] may lead to more pronounced heating of the aqueous environment, causing indirect urothelial thermal injury [9–11]. To manage the double issue of safety management and choice of effective parameters, pre-settings might be helpful.

The aim of this study was to evaluate the relevance of low-power settings to manage effective stone dusting while maintaining safety during TFL lithotripsy. To test laser lithotripsy efficiency, a range of pre-settings as retained by Coloplast TFL Drive interface for stone dusting is compared between the holmium:YAG (Ho:YAG) laser and thulium fiber laser (TFL) in the hands of juniors and experienced urologists, using an in vitro ureteral model. Urothelial damage of both lasers was evaluated in an in vivo porcine model.

#### **2. Materials and Methods**

#### *2.1. Laser Lithotripsy Efficiency*

#### 2.1.1. Laser Systems

The Cyber: Ho 150 WTM (Ho:YAG laser) and the Fiber Dust (TFL) were used as laser generators. Both lasers were from Quanta System (Samarate, Lombardia, Italy). We chose those devices because the laser settings can be set identically in both laser generators (pulse energy and frequency).

#### 2.1.2. Artificial Stones

We produced stone phantoms (5 mm cubes) according to previously described techniques [12]. Matching Begostone Plus powder (Bego France®, Villeurbanne, France) with distilled water, we aimed to reproduce calcium–oxalate monohydrate stones. A «powder to water» ratio of 15:3 was chosen, according to previous in vitro studies [13]. After confection, a drying period of 48 h at 30 ◦C was maintained to minimize the heterogeneity between stones. All stones were weighed with a digital balance (ASP-22E-001 Analytic Balance RADWAG serie) with 0.001 mg accuracy after the drying period.

#### 2.1.3. Experimental Setup

The custom experimental setting, as previously described by [3], consisted of a ureteral model (polymer tube 17 cm length, closed on one side, 7 mm inner diameter), with an opaque tape on a tray with saline (Figure 1).

**Figure 1.** Experimental set up showing (**A**) Six polymer tubes, 17 cm length, closed on one side, 7 mm diameter, with an opaque tape on a tray with saline, used as a ureteral model (**B**) Endovision of the ureteral model with a Lithovue (Boston Scientific®, Maple Grove, MN, USA) and a BegoStone on it (**C**) BegoStone 5 <sup>×</sup> <sup>5</sup> <sup>×</sup> 5 mm3, dry weigh before and after the tests (**D**) Room display, using a Lithovue (Boston Scientific®, Maple Grove, MN, USA). Irrigation was ensured by a combination of a gravity irrigation at 40 cmH2O above the saline tray and a hand-assisted irrigation system.

Trials were conducted using a single use digital flexible ureteroscope (Lithovue, Boston Scientific©, Maple Grove, MN, USA). Irrigation was ensured by a combination of a gravity irrigation at 40 cmH2O above the saline tray and a hand-assisted irrigation system providing on-demand forced irrigation to offer proper visibility, as is done in routine clinical practice (Figure 1).

Participants were divided into two groups according to their skills (five junior urologists and five senior urologists performing more than 80 URS per year). Each one performed 12 continuous lasering sessions (6 with TFL and 6 with Ho:YAG laser) of 3 min with the following laser settings retained from the user interface pre-settings of the Coloplast TFL Drive for stone dusting: 0.5 J/10 Hz, 0.5 J/20 Hz, 0.7 J/10 Hz, 0.7 J/20 Hz, 1 J/12 Hz, 1 J/20 Hz. All tests were performed with a short pulse width from the manufacturer's laser console settings and a 200 μm core-diameter silica fiber.

Data included laser settings (energy and frequency) and total energy. All stone fragments were labeled and dried at room temperature (21 ◦C).

#### 2.1.4. Statistical Analysis

SPSS v25 software (IBM Statistics, Chicago, IL, USA) was used for the statistical analysis. Ablation rates of different laser settings and equipment were recorded and analyzed. For each cohort of laser generators and set of laser parameters, 12 trials were performed. Results are presented as mean and percentages. To assess laser efficiency, one way ANOVA and T-student tests were used. A *p*-value of 0.05 or less was considered significant.

#### *2.2. Urothelial Damage*

#### 2.2.1. Experimental Setup

Studies adhered to the Guide for the Care and Use of Laboratory Animals under an approval of Regional Animal Ethical Committee (#CEEA14). A French Government authorization and were conducted at CERC Faculté de Médecine Nord, Marseille, France (IACUC) (#D-13-055-22).

Three female pigs were used for the experimentation (~40 kg). All procedures were performed under general anesthesia. The anesthetized pigs were placed in the dorsal position. A rigid cystoscopy was used to place a 0.035" guidewire (Terumo, Tokyo, Japan) into the pig kidney, and then a ureteral access sheath (UAS, Retrace 12/14 Fh, Coloplast, Denmark) was placed. A flexible ureteroscope was then positioned in the renal pelvis. An endoscopic evaluation of the renal pelvis was performed (Figure 2). We started the lasering in the renal pelvis, and then, in the distal ureter (after UAS removal), without touching the mucosa.

**Figure 2.** Female pigs (~40 kg). All procedures were performed under general anesthesia and the pigs were placed in the dorsal position. After the first procedure, pigs were kept alive and a second ureteroscopy was performed 18 days later to check for endoscopically tissue lesions. Animals were then sacrificed, and organs were removed for anatomopathological analysis.

#### 2.2.2. Laser Settings

The Cyber: Ho 150 WTM and the Fiber Dust generators (Quanta System Samarate, Lombardia, Italy) were used. Power limits were 20 W (1 J/20 Hz) and 12 W (1 J/12 Hz) in the kidney and ureter, respectively. All tests were performed with short pulse width and a 200 μm core-diameter silica fiber. In all pigs, TFL was used in the left ureter/kidney and Ho:YAG was used in the right ureter/kidney. We performed continuous lasering in the renal pelvis and in the renal papilla for 10 min in each area, to simulate the worst-case scenario. Then, we performed the same technique for 7 min (half on/half off) at the middle of the lumen of the proximal and distal ureter. Continuous irrigation was established at 40 cmH2O.

#### 2.2.3. Method of Temperature Measurement

Before lasering, temperature was continuously recorded by a probe wire retrogradely inserted in the renal cavities that transmitted the intrarenal temperature into a console in the third pig.

#### 2.2.4. Post-Procedure Endoscopic Control

Urothelial injuries heal 5–10 days after their formation. To check tissue healing lesions, pigs were kept alive until a second ureteroscopy 18 days later. An endoscopic diagnosis exploration was made, and their kidneys and ureters were sent for analysis (Figure 2). Pathological analysis was performed by an independent laboratory to assess healing/fibrotic process.

#### **3. Results**

#### *3.1. Laser Efficiency*

After 3 min of continue lasering, the overall ablation rate (AR) percentage of Begostone was 27% (*p* < 0.0001) greater with the TFL than with the Ho:YAG technology (Table 1). When comparing each setting, the overall mean AR was also superior for all groups using the TFL technology. Despite the laser source, differences were also found regarding AR (*p* < 0.001); the more delivered energy, the higher the AR. Similar results were found when comparing energy per stone weight (J/mg). The overall J/mg was 24% (*p* < 0.0001) lower when using the TFL than the Ho:YAG (Table 2) lasers.

**Table 1.** Ablation rate (mg/s) of each scenario by Ho:YAG and TFL lasers, during 3 min of laser lithotripsy. Holmium YAG (Ho:YAG). Thulium fiber laser (TFL).


\* Coloplast TFL Drive user interface pre-settings for stone dusting in the ureter (≤12 W). Red front color means statistical significancy because is < 0.05.


**Table 2.** Comparison thulium fiber laser vs Holmium:YAG. Energy/stone weight (J/mg) in each scenario after 3 min of laser lithotripsy. Holmium YAG (Ho:YAG). Thulium fiber laser (TFL).

\* Coloplast TFL Drive user interface pre-settings for stone dusting in the ureter (≤12 W). Red front color means statistical significancy because is <0.05.

When comparing per expertise, junior urologists performed worse than seniors in all the tests for both lasers, AR percentage and energy per stone weight, but both juniors and seniors performed better when using TFL technology. However, when comparing their performance using TFL versus Ho:YAG lasers, juniors improved more than seniors (15% more AR percentage and 17% less J/mg).

For ureteral stone treatment, the recommended laser power setting is less than 12 W [14]. Suggested settings for ureteral stones have 24% (*p* < 0.0001) better AR percentage and 21% (*p* = 0.004) lower energy per weight (J/mg) with TFL technology.

#### *3.2. Urothelial Damage*

Left and right urinary tracts were treated by TFL and Ho:YAG, respectively. A total of 23 tests were performed using three female pigs. The four defined sites were the renal papilla, renal pelvis and proximal and distal ureter. Due to time constraints, the left distal ureter of the third pig could not be tested.

First evaluation was performed endoscopically during laser activation. After 10 min of continuous lasering in the renal pelvis and the papilla, some small hyperemic lesions were seen in all kidneys with both Ho:YAG and TFL with no subjective differences between lasers using same power settings (Figure 3). No lesions were observed after seven sequential minutes (half on/half off) in the ureter for both lasers. Moreover, the maximal powers used (12 W and 20 W for ureter and kidney, respectively) were not accompanied with per-procedure safety issues. There was no bleeding, no perforation and no carbonization.

During the third pig's laser lithotripsy, the temperature was continuously recorded. In the left kidney (TFL), the temperature increased from 31.5 ◦C to 36.8 ◦C after 1.5 min of lasering. For 3 min, we progressively decreased irrigation until it stopped completely reaching a maximum of 40.2 ◦C. With continuous irrigation, the temperature remained around 36 ◦C during lasering and decreased below 35 ◦C when lasering stopped. For the right kidney (Ho:YAG), the temperature quickly increased from 33 ◦C to 41 ◦C when irrigation was slowed down until it stopped completely and remained between 33 ◦C and 34.6 ◦C during irrigation.

The second evaluation was performed endoscopically three weeks after laser lithotripsy. To access the renal pelvis, a UAS was inserted. Unspecific white marks were found in all kidneys, located at the upper papilla or peri-papilla and the renal pelvis (Figure 3). After

UAS removal, ureteral evaluation was performed, and no lesions were found in neither the proximal nor distal ureter. Of note, in the third pig, where the temperature test was performed and the irrigation was voluntarily reduced, Bellini tubules were visible in both kidneys.

**Figure 3.** Endoscopic images captured during first evaluation and three weeks later, for kidney and ureter sites. Subjectively no differences were found endoscopically between TFL and Ho:YAG during per-procedure and post-procedure safety check.

No differences were detected after anatomopathological evaluation for both lasers and only slight inflammation was seen in some cases. Regarding the renal parenchyma, all animals had interstitial nephritis on both kidneys and showed no differences between Ho:YAG and TFL.

#### **4. Discussion**

According to our results, TFL technology is superior to the Ho:YAG laser with better AR. This is not the first time that the TFL had performed better than the Ho:YAG laser [2,3,8]. Preclinical studies have shown promising results with a more efficient stone ablation rate and a faster ablation speed with TFL [8]. At the same energy and pulse frequency settings, TFL technology produces a significantly lower retropulsion rate than the current Ho:YAG technology [4]. This can be explained by several of the TFL's characteristics. For instance, the fourfold higher wavelength absorption by water may result in greater absorption of laser energy during laser lithotripsy and also explain its high ablation efficiency over any type of stone [15–17]. Additionally, when focusing on peak power and pulse shape, the Ho:YAG's peak power is extremely variable. On the contrary, TFL exhibits a nearly rectangular flattop pulse shape with an almost constant low peak power (500 W) at different settings. At equivalent energy settings, the pulse generated by the TFL in SP mode is longer and has a lower peak power than the one of the Ho:YAG laser in the long pulse and Moses pulse modes [4,15]. These characteristics have been confirmed in several clinical studies after the approval of the US Food and Drug Administration and European CE mark in 2019 and 2020, respectively [6,18]. Even if clinical experiences are still low, we are starting to see high-quality trials with this new technology. Ulvik et al. [7] have recently published the first prospective randomized trial, showing that the TFL is superior to the Ho:YAG laser in terms of the stone-free rate, shorter operative time and fewer intraoperative complications.

In addition, TFL seems to be more worthwhile for learners. When comparing results based on expertise, junior urologists performed worse than experienced urologist in all tests for both AR percentage and energy/stone weight. However, despite that, juniors performed better when using TFL technology, showing a reduced learning curve and lack of need to constantly adapt to a continuously changing stone position. This can be explained by the lower degree of retropulsion with TFL, which helps to improve the precision and vision during stone ablation [19]. Several lab studies have shown that TFL has lower retropulsion than Ho:YAG laser [4,18,20], leading to a more efficient lithotripsy [21]. Several clinical trials have also shown that TFL is a safe and effective modality for laser lithotripsy because of the lower retropulsion and minimal complication rate [22–25].

Although Ho:YAG has demonstrate an excellent safety profile, being considered as the more successful laser, TFL wavelength (1940 nm) is closer to water absorption peak, which results in four-fold higher abortion than Ho:YAG. This facilitates higher absorption of energy and increased ablation efficiency [8]. However, this higher rate of energy transfer to the stone and the surrounding fluid could potentially lead to indirect thermal damage [9–11]. Recently, Belle JD et al. [11] have demonstrated, in an in vitro silicone kidney-ureter model, that high-power lasers are associated with a risk of complications from thermal damage and therefore advocate using rather conservative laser settings for ureteroscopy laser lithotripsy. According to previously published papers, temperature rises proportionally to power [25], and power limits are settled at 20–30 W and 10–15 W for the kidney and ureter, respectively, to avoid cellular thermal damage [3,9,10]. Our study results are in line with that statement. We remark that low power settings are safe for the urothelium, as we confirmed in our second look of the porcine kidney. Moreover, the use of saline irrigation during the procedure has shown to be critical to avoid excessive temperature rises, and studies evaluating temperature rise with both Ho:YAG and TFL have demonstrated a good safety profile when continuous irrigation was applied during laser activation [10,26,27]. Similar findings are described during our trial, we were continuously lasering with continuous irrigation at 40 cmH2O and temperature remained at 36.8 ◦C and 34.6 ◦C for TFL and Ho:YAG, respectively.

Regarding laser effectivity, we tried to simulate a real-life scenario, but the first limitation was an incomplete simulation of actual laser lithotripsy conditions in a urinary tract. Such conditions included ureteral peristalsis, respiratory movements and convection, which plays major roles during laser lithotripsy in the ureter. However, the aim of our study was to compare different settings and the obtained ablation rate. Stone phantoms, rather than human stones, were used. We required samples of approximately uniform mass, geometry, and composition, which could not be achieved practically with human stones. The third limitation involved the BegoStones immediately absorbing water through cracks and pores, which would have influenced the results of dehydrated phantoms in water. It should also be mentioned that the so-called dry phantoms in our study had not been desiccated. However, we have a control stone that was submerged into the saline tray without lithotripsy treatment, and we stored the stones in similar conditions. When its weight was the same as before the experiment, we assumed that the rest were dried too. In the porcine model, we were not lasering to stones, but we simulated the worst-case scenario through 10 min continuous lasering in the same place.

#### **5. Conclusions**

In vitro, laser lithotripsy efficiency is higher with the TFL than with the Ho:YAG laser. Indeed, despite low power settings, AR was significantly higher, and less energy was needed to ablate 1 mg of stone with the TFL. Interestingly, it seemed that junior urologists had a faster learning curve with the TFL than with the Ho:YAG laser. Concerning laser safety, both laser technologies are equally safe. We can conclude than the Coloplast TFL Drive GUI pre-set values are effective and safe when working with 20 W in the kidney and 12 W in the ureter.

**Author Contributions:** Conceptualization, A.S. and M.C.; methodology, O.T.; formal analysis, M.C.; investigation, A.S., M.C. and O.T.; original draft preparation, A.S.; writing—review and editing, A.S. and B.S.; supervision, O.T. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** The study was conducted according to the guidelines of the Declaration of Helsinki, and adhered to the Guide for the Care and Use of Laboratory Animals under an approved Institutional Animal Care and Use Committee (IACUC) protocol (#D-13-055-22).

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Ask to the authors.

**Conflicts of Interest:** Alba Sierra and Mariela Corrales have nothing to disclose. Olivier Traxer is a consultant for Boston Scientific, Coloplast, EMS, IPG, Quanta and Rocamed, but has no specific conflicts relevant to this work.

#### **References**


**Disclaimer/Publisher's Note:** The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

## *Article* **Real Time Intrarenal Pressure Control during Flexible Ureterorrenscopy Using a Vascular PressureWire: Pilot Study**

**Alba Sierra 1,2,3, Mariela Corrales 2,3, Merkourios Kolvatzis 2,3,4, Steeve Doizi 2,3 and Olivier Traxer 2,3,\***


**Abstract:** (1) Introduction: To evaluate the feasibility of measuring the intrapelvic pressure (IPP) during flexible ureterorenoscopy (f-URS) with a PressureWire and to optimize safety by assessing IPP during surgery. (2) Methods: Patients undergoing f-URS for different treatments were recruited. A PressureWire (0.014", St. Jude Medical, Little Canada, MN, USA) was placed into the renal cavities to measure IPP. Gravity irrigation at 40 cmH2O over the patient and a hand-assisted irrigation system were used. Pressures were monitored in real time and recorded for analysis. Fluid balance and postoperative urinary tract infection (UTI) were documented. (3) Results: Twenty patients undergoing f-URS were included with successful IPP monitoring. The median baseline IPP was 13.6 (6.8–47.6) cmH2O. After the placement of the UAS, the median IPP was 17 (8–44.6) cmH2O. With irrigation pressure set at 40 cmH2O without forced irrigation, the median IPP was 34 (19–81.6) cmH2O. Median IPP during laser lithotripsy, with and without the use of on-demand forced irrigation, was 61.2 (27.2–149.5) cmH2O. The maximum pressure peaks recorded during forced irrigation ranged from 54.4 to 236.6 cmH2O. After the surgery, 3 patients (15%) presented UTI; 2 of them had a positive preoperative urine culture, previously treated, and a positive fluid balance observed after the surgery. (4) Conclusion: Based on our experience, continuous monitoring of IPP with a wire is easy to reproduce, effective, and safe. In addition, it allows us to identify and avoid high IPPs, which may affect surgery-related complications.

**Citation:** Sierra, A.; Corrales, M.;

Kolvatzis, M.; Doizi, S.; Traxer, O. Real Time Intrarenal Pressure Control **Keywords:** endourology; intrapelvic pressure; intrarenal pressure; ureteroscopy

during Flexible Ureterorrenscopy

Using a Vascular PressureWire: Pilot

Study. *J. Clin. Med.* **2023**, *12*, 147.

https://doi.org/10.3390/jcm12010147 **1. Introduction**

Academic Editor: Enrico Checcucci Received: 6 November 2022 Revised: 19 December 2022 Accepted: 21 December 2022 Published: 24 December 2022 The development of fibre optic technology, digital ureteroscopes, and novel laser techniques have allowed the downsizing of flexible ureteroscopes, allowing not only treatment but also the diagnosis of many upper urinary tract conditions, such as kidney stones, ureteral strictures, and low-risk upper urothelial tumours [**? ?** ]. Nevertheless, an adequate irrigation flow is required to achieve and maintain good visualization during these procedures [**?** ].

**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). With the downsizing of ureteroscopes, the working channel is typically reduced to 3.6 Fh. In endoscopic procedures, visibility is crucial, and it depends largely on the balance between the inflow, based on the irrigation pressure system and the working channel size, and the irrigation outflow, which depends on scope size and its relationship with the ureteral access sheath (UAS) [**?** ]. The intrapelvic pressure (IPP) reached during f-URS is a result of irrigation inflow and outflow [**?** ]. The physiological IPP ranges from 0 to 5 cmH2O and the pyelo-venous backflow occurs at pressures of 40.8–47.6 cmH2O [**? ?** ]. During f-URS, when a disbalance occurs, high levels of IPP may be reached intraoperatively, causing pyelo-venous, and pyelo-lymphatic backflow or even rupture of the collecting system, possibly leading to peri-renal hematoma or urosepsis [**???** ]. Prior in vivo studies

have reported pressures as high as 436.9 cmH2O during f-URS [**?** ], massively exceeding the pressure of pyelovenous backflows.

Despite some clinical experiences [**?** ] with the current endourology armamentarium, we are not able to measure real-time in vivo intrarenal pressure during endourological procedures. The aim of our study is to evaluate simultaneously the IPP values using a vascular PressureWire and avoid sudden pressure increases during different f-URS procedures.

#### **2. Materials and Methods**

#### *2.1. Study Design*

A prospective pilot study of consecutive patients undergoing f-URS for different treatments, including kidney stone disease, pyelo-ureteral junction syndrome (UPJ) and diagnosis/treatment for upper tract urothelial carcinoma (UTUC), was performed between March and April 2022

#### *2.2. Method of IPP Measurement*

The PressureWire (St. Jude Medical, Saint Paul, MN, USA) was used before by Doizi et al. for IPP monitoring [**?** ]. This 0.014 wire is approved and routinely used by cardiologists to assess fractional flow reserve in coronary arteries. The distal 3 cm of the wire, where the digital sensor is positioned to measure pressure, is made of soft platinum, which is floppy, radiopaque, hydrophilic and allows for positioning without renal trauma. In the following 28 cm, the wire is made of a polytetrafluoroethylene coating and is flexible and hydrophilic. Wirelessly, the pressure signal is transmitted to a console (QUANTIEN system) that displays the pressure (Figure **??**). Pressure is recorded every second. The pressure is measured in mmHg and the available range is from −30 to 300 mmHg (−40.8 to 407.9 cmH2O). Its accuracy is ±1 mmHg plus ± 1% (≤50 mmHg) ± 3% (>50 mmHg). Pressure values measured in mmHg were multiplied by 1.35951 to convert them in cmH2O.

**Figure 1.** Wireless system. The PressureWire is activated by pressing a button (green light) and automatically connected wirelessly to a console (QUANTIEN system). The zeroing must be completed before the PressureWire placement, outside the patient. Once it is connected, it starts to simultaneously transmit the pressure signal to the screen.

#### *2.3. Procedures*

Perioperative antibiotic prophylaxis was administrated following the local protocol. All procedures were performed under general anaesthesia. Each procedure began with a cystoscopy and the placement of a hydrophilic guidewire in the renal pelvis under fluoroscopic guidance. A dual lumen ureteral catheter (Cook Medical, Bloomington, IN, USA) was then inserted and the PressureWire was placed in the renal pelvis for IPP measurements (Figure **??**). Once the dual lumen catheter was removed, the f-URS was either passed directly over the hydrophilic guidewire or, when indicated, through a UAS inserted over the hydrophilic guidewire (Retrace 10/12 or 12/14, 35 cm, Coloplast, Humlebaek, Denmark). In some cases, PressureWire was placed into the UAS (Figure **??**). Retrograde intrarenal surgery (RIRS) was performed using a flexible digital re-usable ureteroscope, the Flex—Xc (Karl Storz, Tuttlingen, Germany), with a constant 0.9% saline irrigation

pressure (40 cmH2O) at ambient temperature and a manual pump (Traxerflow Dual Port, Rocamed, Monaco), allowing on-demand forced irrigation when a better view was required. All of the interventions performed by an experienced endourologist (OT). The assistant controlled the pressure during the entire surgery, ensuring good vision and trying not to exceed values above 60 cmH2O (Figure **??**). When laser treatment was needed, a thulium fibre laser (SOLTIVE Premium, Olympus, Tokio, Japan or FIBERDUST, Quanta System, Samarate, Italy) was used. At the end of each surgery, we inserted a ureteral stent (Double J) for 7–10 days. Patients were followed in the postoperative period to identify any possible complications.

**Figure 2.** Pressure wire placement intro renal pelvis: (**A**) fluoroscopic image of PressureWire (green) and safety wire (red) in the renal pelvis. (**B**) Endoscopic vision of the renal pelvis with a PressureWire (green) and safety wire (red) going inside the upper calyx. (**C**) Endoscopic vision before starting lithotripsy of a dihydrate calcium oxalate stone with a safety wire (red), PressureWire (green) and fibre laser in the renal pelvis.

**Figure 3.** (**A**) Placement of PressureWire after the use of a dual lumen ureteral access catheter (Cook Medical, Germany). (**B**) PressureWire was placed through the UAS (Retrace 10/12, 35 cm, Coloplast, Denmark) with a digital reusable flexible ureterorenoscope (Flex-XC, 8.5Fh, Storz, Germany) inside. SW, safety wire. PW, PressureWire. DL, dual lumen.

**Figure 4.** Pressure is simultaneously transmitted to the screen during endoscopic procedure. The pressure is measured in mmHg and the available range is from −30 to 300 mmHg. In this figure, during manual assisted irrigation (Traxerflow Dual Port, Rocamed, Monaco), we achieve IPP at 76 mmHg.

#### *2.4. Data Collection*


In case of stone disease, patients underwent non-contrast-enhanced CT for stone volume, which was obtained with the formula of an ellipsoid (4/3 × π × radius length × radius width × radius depth). Median IPP values, peak pressures, and pressure patterns with and without the scope in the renal cavity were examined, as well as the influence of ondemand irrigation during the surgical procedure. The fluid balance (FB) was the difference between the saline irrigation volume used during the surgery and the volume in the vacuum at the end of the surgery. During the hospitalisation, postoperative complications were recorded. For statistical analysis, categorical variables were measured as percentages and numerical variables were expressed as medians (interquartile range (IQR)).

#### **3. Results**

Of the 20 patients included in this study, 55% (n = 11) were male and 45 (n = 9) female. The median age was 51 (19–79) years old. Placement of the PressureWire succeeded in all cases and IPP measurements were obtained in all cases (Table **??**).

Two patients with UTUC, one for surveillance and the other one for endoscopic treatment, had baseline pressures of 15 cmH2O in both cases. Therapeutic IPP was 57 cmH2O. However, the maximum peak pressure recorder was 114.2 cmH2O.

One patient with pyelo-ureteral junction syndrome demonstrated a pressure two times higher than the baseline pressure after the administration of furosemide iv (1 mg).

f-URS was performed for stone lithotripsy in 85% of cases (n = 17). Four of them were pre-stented. The median stone burden was 864 (50–9000) mm3. Overall, 52% (n = 9) were calcium oxalate stones. The median baseline IPP was 13.6 (6.8–47.6) cmH2O. UAS was used in 14 patients (70%), mostly 10/12 Fr, according to the surgeon's choice. After UAS placement, the median UAS IPP was 17 (8–44.6) cmH2O. During f-URS, with the endoscope in the renal cavity and irrigation pressure set at 40 cmH2O without any forced irrigation, the median IPP was 37.4 (19–81.6) cmH2O when UAS was used and 35.2 (21.8–64) cmH2O without UAS. We controlled the pressure simultaneously during all of the surgeries. When forced irrigation was used, immediate IPP changes were observed, according to the way in which the assistant used the irrigation system. The median IPP during therapeutic period with the use of on-demand forced irrigation was 61.2 (27.2–149.5) cmH2O. The maximum pressure peaks recorded during this period ranged from 54.4 to 238 cmH2O.

The median surgery time was 149.5 (60–256) min. Positive preoperative urine culture was detected in 25% (n = 5) patients, all of them with renal stones (Table **??**). According to the antibiogram, antibiotherapy was started 3 days before the surgery in all cases. Overall, 15% (n = 3) of patients were diagnosed with a UTI after the procedure. The complication rate was low and mostly Clavien–Dindo grade I and II. There were no complications related to PressureWire placement.


**Table 1.** Patient characteristics and intrapelvic pressures during flexible ureteroscopy.



**Table 2.** Relationship between peak pressure, fluid absorption and postoperative complications.

#### **4. Discussion**

Pyelovenous backflow, which occurs at pressures of 40.8–47.6 cmH2O, is an event that most urologists try to avoid [**? ?** ]. That is why an IPP around 40 cmH2O is recognised as an aspirational threshold and should be the goal during endourological procedures [**?** ]. In our pilot study, although IPP was rigorously controlled, maintaining IPP around 40 cmH2O was not feasible to maintain good visualization. We target pressures as low as possible, achieving 61.2 cmH2O median IPP. In a recent systematic review, IPP at 40 cmH2O was also exceeded during ureterorenoscopic procedures, specially without UAS [**?** ]. Additionally, if we consider high-power laser lithotripsy, moderate irrigation is needed for the laser to be safe, because if irrigation rates decrease, we can produce a significant temperature increase, potentially resulting in urothelial tissue injuries [**?** ]. Understanding this fact is crucial when interpreting findings, since improving drainage may be preferable compared to decreasing irrigation pressure/flow.

Unlike prior in vivo human studies where a ureteral catheter or a nephrostomy tube were used [**? ?** ], we placed a 0.014" PressureWire in renal cavities. This IPP method measurement was described previously by Doizi et al. [**?** ]. This system offers several advantages: it can be used for endoscopic procedures with all scope brands, and as the wire is placed into renal cavities, we can control IPP throughout the the procedure, because in addition to working along the ureter to treat, e.g.., a ureteral stone, which is important, it can work up to the pyeloureteral junction [**? ?** ]. However, its small size prevents us from using it as a safety wire, needing us to place both the PressureWire and a safety wire.

Regardless of the IPP measurement method, with gravity irrigation at 40 cmH2O, similar baseline IPPs were also reported in the literature, ranging from 23.8 to 57 cmH2O without UAS and 13.14 to 33.99 cmH2O with a 10/12 UAS [**?** ]. In addition, the scope IPP without UAS was two to three times higher than baseline IPP, which demonstrates once again that higher IPP is achieved without UAS [**?** ]. Concerning therapeutic IPP, no comparison can be performed with previous studies, since many parameters differ: f-URS model, gravity and forced irrigation, pre-stenting and use or not of UAS and its size.

Prior in vivo human studies have reported peak pressures above 400 cmH2O [**???** ]. In our cohort, by means of simultaneous IPP control, we halved these values for a short period of time. By means of simultaneous IPP control, we can quicky react to decreased IPP, avoiding pathological kidney changes reported in the literature [**?** ]. In this line, in the immediate follow-up, no urinary extravasation was identified. However, fluid absorption was noted in four patients. Fluid absorption during f-URS usually remains low, mainly due to the smaller instrument calibre and the small irrigation channel. Nevertheless, increasing the flow to maintain optimal visibility necessitates the use of high-pressure irrigation, thus increasing the risk of fluid extravasation. IPP is not the only parameter to consider during fluid absorption; urothelial damage and surgery length are also important. Cybulski et al. reported that there is approximately 1 mL of irrigation fluid absorbed per minute of URS time at 271.9 cmH2O [**?** ].

Additionally, the procedure time is independently correlated with increased postoperative fever and SIRS rates [**?** ]. There is probably a correlation between IPP and infectious complications such as UTI and sepsis during endourological procedures, as well as other factors such as patient age, stone size and type, and length of the surgery [**? ?** ]. For instance, 15% of the patients in our series presented with postoperative UTI despite therapeutic IPP at 40 cmH2O, meaning that other factors may contribute to the development of infectious complications.

We are convinced that the next step to improve safety during intrarenal procedures will be IPP monitoring. In this line, the recently developed LithoVueTM Elite System (BostonScientific, Boston, MA, USA) might contribute to safety and will provide us with more information about intrarenal pressure during endourologic procedures. However, for now, this new device needs to be evaluated, since the post-market study recently started in July 2022. Moreover, as the pressure sensor is located on the scope's tip, to measure IPP we will need the scope to be placed inside the kidney, while with the PressureWire we can control IPP throughout the procedure. In future research, it will be interesting to compare both methods of pressure monitoring.

#### **5. Conclusions**

In our experience, the use of the PressureWire for IPP measurement during therapeutic and diagnosis f-URS is simple, safe, reproducible, and independent of the f-URS procedure. Continuously monitoring the IPP in real time allows us to identify and avoid high IPPs, which may lead to surgery-related complications.

**Author Contributions:** Conceptualization, O.T. and S.D.; methodology, O.T.; formal analysis, M.C.; investigation, A.S. and M.K.; data curation, M.K.; writing—original draft preparation, A.S.; writing—review and editing, M.C.; supervision, O.T. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Ethical review and approval were waived for this study, due to prior published paper using same PressureWire in humans.

**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.

**Data Availability Statement:** Data is unavailable due to privacy.

**Conflicts of Interest:** Alba Sierra, Mariela Corrales and Merkourios Kolvatzis have nothing to disclose. Olivier Traxer is a consultant for Boston Scientific, Coloplast, EMS, IPG, Quanta and Rocamed, but has no specific conflicts relevant to this work.

#### **References**


**Disclaimer/Publisher's Note:** The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

## *Article* **Factors Affecting the Usage of Wearable Device Technology for Healthcare among Indian Adults: A Cross-Sectional Study**

**Vathsala Patil 1, Deepak Kumar Singhal 2,\*, Nithesh Naik 3,4,5,\*, B. M. Zeeshan Hameed 4,5,6, Milap J. Shah 4,7, Sufyan Ibrahim 4,8, Komal Smriti 1, Gaurav Chatterjee 9, Ameya Kale 10, Anshika Sharma 11, Rahul Paul 4,12,13, Piotr Chłosta <sup>14</sup> and Bhaskar K. Somani <sup>15</sup>**


**Abstract:** Background: Wearable device technology has recently been involved in the healthcare industry substantially. India is the world's third largest market for wearable devices and is projected to expand at a compound annual growth rate of ~26.33%. However, there is a paucity of literature analyzing the factors determining the acceptance of wearable healthcare device technology among low-middle-income countries. Methods: This cross-sectional, web-based survey aims to analyze the perceptions affecting the adoption and usage of wearable devices among the Indian population aged 16 years and above. Results: A total of 495 responses were obtained. In all, 50.3% were aged between 25–50 years and 51.3% belonged to the lower-income group. While 62.2% of the participants reported using wearable devices for managing their health, 29.3% were using them daily. technology and task fitness (TTF) showed a significant positive correlation with connectivity (*r* = 0.716), health care (*r* = 0.780), communication (*r* = 0.637), infotainment (*r* = 0.598), perceived usefulness (PU) (*r* = 0.792), and perceived ease of use (PEOU) (*r* = 0.800). Behavioral intention (BI) to use wearable devices positively correlated with PEOU (*r* = 0.644) and PU (*r* = 0.711). All factors affecting the use of wearable devices studied had higher mean scores among participants who were already using wearable devices. Male respondents had significantly higher mean scores for BI (*p* = 0.034) and PEOU (*p* = 0.009). Respondents older than 25 years of age had higher mean scores for BI (*p* = 0.027) and Infotainment (*p* = 0.032). Conclusions: This study found a significant correlation with the adoption and acceptance of wearable devices for healthcare management in the Indian context.

**Citation:** Patil, V.; Singhal, D.K.; Naik, N.; Hameed, B.M.Z.; Shah, M.J.; Ibrahim, S.; Smriti, K.; Chatterjee, G.; Kale, A.; Sharma, A.; et al. Factors Affecting the Usage of Wearable Device Technology for Healthcare among Indian Adults: A Cross-Sectional Study. *J. Clin. Med.* **2022**, *11*, 7019. https://doi.org/ 10.3390/jcm11237019

Academic Editor: Enrico Checcucci

Received: 21 October 2022 Accepted: 24 November 2022 Published: 28 November 2022

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

**Keywords:** wearable healthcare devices; fitness devices; wearable technology; infotainment; mobile health

#### **1. Introduction**

Wearable devices are instruments that can be worn on the body, typically on or near the skin, and are equipped with sensors capable of detecting various physiological variables. Wearable technology includes devices that can be placed on the limbs, torso, or head such as watches, bracelets, phones, glasses, head-mounted displays, hearing aids, suits, belts, shoes, and patches that can measure various physiological parameters, which include heart rate, rhythm, blood pressure, oxygen saturation, skin temperature, steps traveled, calorie expenditure estimates, blood glucose levels, and UV radiation exposure [1]. This data can be used for physiological-related research studies, detection of aberrant parameters for clinical diagnosis or prognosis to provide biological feedback to the user thereby aiding in monitoring, and even as an educational tool for promoting health and physical fitness. One of the earliest examples of wearable technology, as it pertains to the field of medicine, are portable hearing aids invented in the 19th century [2]. Norman Holter's discovery of the first wireless electrocardiogram in 1962 ushered in the era of modern medical wearable gadgets [3,4]. The internet enables health-directed wearable devices to stay connected while continuously measuring and recording data. This system is now referred to as "Connected Health" [5].

Newer studies have aimed at early identification and prediction of inflammatory disease, cancer diagnosis, measuring blood alcohol levels, etc. through smartphone screens. Combining deep neural network-machine learning technology with biological age estimation has further enhanced its feasibility and usage [6–10]. In recent years, the world has seen a wave of adoption of wearable devices even among the middle to high-income socio-economic demographics. A recent systematic review and meta-analysis of multiple randomized controlled trials of consumer wearable activity trackers (CWAT) found that they can improve physical activity in sedentary older adults who are overweight/obese or with chronic respiratory diseases and reduce the systolic blood pressure, waist circumference and low-density cholesterol in individuals with type 2 diabetes mellitus and cardiovascular diseases [11]. Wearable devices such as smartwatches have been seen to benefit psychological wellness in individuals with cognitive disorders [12].

India is now the world's third-largest market for wearable devices. Several studies have found that an increasing number of individuals are purchasing wearable devices to promote fitness and manage their health [13,14]. A recent study determined that consumers in India are motivated by health and autonomy, health self-efficacy, and technological innovativeness to adopt wearable healthcare devices [15,16]. The COVID-19 pandemic encouraged a rapid, massive expansion of remote health management and firmly established telehealth as an accessible, validated model of healthcare. The data on the pandemic's effect on actual wearable device use in healthcare settings is limited. Studies examining the perception of wearable device technology among adults in India are limited in the literature. Hence, the present study aimed to analyze the perception of Indian Professionals about wearable device technology in terms of its usage in personal health management.

#### **2. Materials and Methods**

#### *2.1. Data Collection and Ethical Considerations*

A cross-sectional study was carried out from January 2022 to May 2022 using an online questionnaire, using an anonymized Google form platform, enquiring about participants' use of wearable devices for healthcare, socio-demographic factors, and factors affecting the use of wearable devices for healthcare. The technology acceptance model (TAM) and technology and task fitness (TTF) models of technology adoption were used for the survey. Data acquisition and analysis were performed after the approval by the Institutional Ethical

committee (ethical approval number FMIEC- 94/2021). Informed consent was obtained from all the participants before the study and the data was analyzed by an independent third party.

The questionnaire gathered information regarding demographics, behavioral intention (BI), perceived usefulness (PU), perceived ease of use (PEOU), subjective feelings about technology, task fitness, connectivity, communication, healthcare, infotainment, fashionability, wearability, and subjective norms. The questionnaire (available as Supplementary Materials) was divided into 11 sections, with 3 items each directed at identifying the subject's feelings concerning wearable devices according to factors described in the TAM model and factors derived from the TTF models, and was distributed to the participants. The response was documented based on a 5-point answer choice based on the Likert scale as follows: (1)—Strongly Disagree/Very Rarely, (2)—Disagree/Rarely, (3)—Undecided/Occasionally, (4)—Agree/Often, and (5)—Strongly Agree/Very Often.

#### *2.2. Survey and Participant Characteristics*

Respondents consisted majorly of individuals involved in medical science (undergraduate students, postgraduates, consultant physicians) and the engineering field. The questionnaire was surveyed using the Google Forms platform, which focused on the perception and stated usage of wearable devices by the participants. The inclusion criteria for the study included adults >16 years, able to navigate through the online survey platforms, and comfortable with the interpretation of the English language. An information sheet along with informed consent was displayed and documented respectively at the start of the survey. Participation in this survey was voluntary with no incentives provided to the respondents. Survey data collected via Google Forms was stored on the Google Spreadsheet platform on Google Drive, access to which was limited only to members of the research group.

#### *2.3. Data Analysis*

The responses to the survey were analyzed using the SmartPLS software version 3.0.M3, with PLS path modeling. Descriptive variables of gender, age, qualification, income, and reports of usage of wearable devices for personal healthcare were expressed as categorical variables. Age data were grouped according to less than 18 years old, 18 to 25 years old, 25 to 50 years old, and older than 50 years. Qualification data were grouped according to (1) "10 + 2 schooling", (2) "graduate", (3) "post-graduate", and (4) "diploma" categories. Income data were grouped from a personal annual income of (1) less than 50,000 Rs to 500,000 Rs. (Lower), (2) 500,000 to 2,500,000 Rs. (Middle), (3) 2,500,000 to 5,000,000 Rs. (Upper Middle) and (4) greater than 5,000,000 Rs. (Elite). Wearable device use-frequency data was grouped into (1) once a year, (2) more than once a year, (3) once in a month, (4) once or twice in 3 months, (5) once or twice in a week, and (6) daily. Wearable device usage for healthcare was assessed using a binary "yes" or "no" response. Usage frequency data were grouped according to (1) daily, (2) once or twice in a week, (3) once in a month, (4) once or twice in 3 months, (5) more than once a year, and (6) once a year.

Correlation between technology-task fitness and connectivity, communication, healthcare, infotainment, perceived usefulness, and perceived ease of use was tested by calculation of the Pearson correlation coefficient with a 2-tailed significance level set at 5% (alpha < 0.05). Pearson correlation coefficient was calculated with a 2-tailed significance level set at 5% (alpha < 0.05) between behavioral intention and fashionability, s, Subjective norms, perceived usefulness, and perceived ease of use. An independent sample *t*-test was performed to compare mean scores of all factors in respondents who reported using wearable devices for healthcare versus those who reported not using them, to compare male versus female respondents, and between the less than 25 years age group and more than 25 years age group (*p* < 0.05). Figure 1 shows the proposed research model with the various factors considered to evaluate the influence of the usage or barriers of wearable device technology for healthcare.

**Figure 1.** Proposed research model.

#### **3. Results**

A total of 495 responses were obtained from the Google form questionnaire. General data for the participants are as follows: 65.5% of respondents were male and 34.5% were females; 50.3% were between 25–50 years of age; 51.3% reported being in the lower-income group (annual income less than Rs. 50,000 to Rs. 500,000); 62.2% of participants reported already using wearable devices for managing their health; 29.3% reported using wearable devices daily. Table 1 shows the demographic characteristics of the participants considered in the present study.

**Table 1.** Demographic characteristics of study participants.


It was found that TTF moderately positively correlated with communication (*r* = 0.637) and infotainment (*r* = 0.598) and highly positively correlated with connectivity (*r* = 0.716) and health care (*r* = 0.780). Perceived usefulness (*r* = 0.792) and perceived ease of use (*r* = 0.800) were also found to be strongly correlated. Behavioral intention to use wearable devices was positively correlated to factors such as perceived usefulness, perceived ease of use, fashionability, wearability, and subjective norms. However, it was mildly correlated with fashionability (*r* = 0.472), moderately correlated with wearability (*r* = 0.642), subjective norms (*r* = 0.594), and perceived ease of use (*r* = 0.644), and highly correlated with perceived usefulness (*r* = 0.711). Table 2 shows the correlation values of the respective factors affecting technology and task fitness and behavioral intention in using wearable devices.


**Table 2.** Factors affecting technology and task fitness (TTF) and Behavioral Intention to use Wearable Devices [N = 495].

\*\* Correlation is significant at the 0.01 level (2-tailed).

Table 3 shows that all factors have significantly higher mean scores among those participants who are already using wearable devices as compared to non-users (*p* < 0.001). There is no significant difference in mean scores of all the variables among the males and females except for behavioral intention to use wearable devices and perceived ease of use of devices. Males have significantly higher mean scores for behavioral intention (*p* = 0.034) and perceived ease of use (*p* = 0.009). There is no significant difference in mean scores of any of the variables among the two different age groups except for behavioral intention to use wearable devices and infotainment. The participants who are more than 25 years old have significantly higher mean scores for behavioral intention (*p* = 0.027) and infotainment (*p* = 0.032).

**Table 3.** Mean scores of different factors affecting the use of wearable devices across already usage of wearable devices, gender, and age.



**Table 3.** *Cont.*

Independent Sample *t*-test, \* *p*-value < 0.05 is considered statistically significant.

#### **4. Discussion**

In this survey, we analyzed whether socio-demographic and usage-determining factors correlated with self-reported use of wearable devices for healthcare in a subset of the Indian population, mainly medical and engineering professionals. This study provides empirical support for the hypothesis that factors, drawn from the TAM and TTF models along with additionally considered variables determining the use, are positively correlated with the self-reported use of wearable devices for healthcare.

#### *4.1. Theoretical Models to Study the Acceptance of Technology among Users*

Various theories of behavior have been formulated giving rise to different models predicting human behavior. A prominent and well-studied model is the technology acceptance model (TAM). This is based on a major theory of human behavior, the theory of reasoned action (TRA). Another common model is the task-technology fitness (TTF) model used to study the congruence of new information systems with task requirements.

The theory of reasoned action (TRA) states a person's performance of a specified behavior is determined by their behavioral intention (BI) to perform it, which in turn is determined by the person's attitude (A) and subjective norm (SN) concerning the behavior. According to the TAM model, two main factors influence the acceptance of new technology by users—perceived usefulness (PU) and perceived ease of use (PEOU). PU has been defined as "the degree to which a person believes that using a particular system would enhance their job performance". PEOU has been defined as "the degree to which a person believes that using a particular system would be free from effort". Both influence attitude (A) toward using the technology which in turn influences BI, which determines the actual usage [17]. PU and PEOU are independently correlated with a higher frequency of selfreported use of new information technology by users [17–20]. TAM was modified to incorporate SN from TRA, such that SN acted as external variables that affected PU and PEOU. The TAM model has been widely used to study the adoption of disparate projects in the field of information technology [20–24]. The TTF model proposes that user performance is improved if there is a congruence of the technology with the task at hand. It suggests that technology will be used and will improve user performance only if tool functionality fits task requirements [25].

TAM focuses on attitudes behind technology adoption, while TTF focuses on the operational aspects. Subsequent research has tried to integrate the TTF and TAM models to better explain technology acceptance and proposed that TTF factors influence PU and PEOU [26].

#### *4.2. Variables Studied and Analyzed during Our Survey*

A recent study by Chang et al. (2016) proposed a technology acceptance model for wearable healthcare devices based on the TAM–TTF model and defined TTF factors for wearable healthcare devices as connectivity, communication, healthcare, and infotainment. This study also proposed that external factors such as subjective norms and device factors of wearability and fashionability influence BI [27].

Drawing from the TAM and TTF models, we constructed an abbreviated questionnaire, similar to the previously used and validated construct by Chang et al., consisting of threequestion items, each to assess BI, PU, PEOU, and TTF using the Likert scale. Different from the original TTF construct, this model assessed a subjective sense of task and technology fitness, rather than focused objective factors. Factors for TTF for wearable devices were used as defined by previous studies. Connectivity describes the interaction between devices using Bluetooth or wireless network technology. Communication refers to the function of wearable devices that allow users to communicate with other users, such as by making phone calls, text messaging, etc. Healthcare refers to how wearable devices assist the user in managing their health. This was assessed using a subjective three-question item construct. Infotainment refers to factors such as the displayed information about heart rate and distance statistics to guide improvement or seek enjoyment and motivation as users engage in health-promoting behavior. Fashionability refers to fashion factors related to the design of the wearable device. This has been seen as weakly significant or correlated in comparison with the use of wearable devices for healthcare management purposes. Wearability refers to design factors of the wearable device related to form and fit, ease of wearability, access to the device, etc. Wearability is strongly positively correlated with task-technology fitness. Subjective norms are social factors, such as what an individual who is important to the user thinks about the device. Evidence for subjective norms affecting the use of new technology has been seen to be more significant for female users in the older age group in the early stages of use, but these findings are more important in mandatory usage settings. In the case of voluntary use such as wearables, subjective norm falls to how it affects attitude and behavioral intention [28].

Using these models of human behavior as a base, we have tried to construct our theoretical model to predict the adoption of wearable devices for healthcare and gauge the response of a sub-section of the Indian population, as explained above. We have not elicited what type of wearable devices were used by our respondents, or how they used them for managing health. However, wearable fitness trackers with pedometers and accelerometers are the most common wearable devices used for healthcare found on the market worldwide, while in India, the market is largely dominated by "hearables", smartwatches comprising the fastest growing device segment. This descriptive study largely applies to these devices [29,30].

#### *4.3. Adoption of Wearable Healthcare Devices*

Wearable devices and their specific use in healthcare management have been studied using various validated human behavior models, such as the TAM model, the successor UTAUT with protection motivation theory, and privacy calculus theory, which have recently evolved in the field to explain users' privacy concerns [31,32]. These studies have analyzed various factors that influence the adoption, continued use, frequency of use, and discontinuation of wearable devices. A recent national survey in the USA, studying the reception of wearable device technology in the western world, estimated that close to 30% of adults are using wearable healthcare devices. This nationwide survey also correlated socio-economic, demographic, health, and technology, self-efficacy attributes to the actual use of wearable devices [33].

In the present study, we found that subjective measurements of task-technology fitness (TTF) are strongly positively correlated with device factors of connectivity and healthcare, and moderately positively correlated with communication and infotainment. This reflects the users' perceptions that wearable devices are used mainly for healthcare, and for achieving health goals. The synchronization and connectivity of the wearable device to other devices are necessary for the ease of transfer of health data. Users/participants in the present study were not regularly using wearable healthcare devices for communication tasks such as making calls or messaging, as well as infotainment.

TTF measures were found to be strongly correlated with PU and PEOU. PU is strongly correlated with BI in previous studies using the TAM model on wearable devices and other technologies that are also in accordance with our study [20]. PEOU is less strongly correlated, which may be due to the moderating influence of PU on PEOU, which has been well described in the literature [17,25]. Wearability and subjective norm were moderately positively correlated with BI, and fashionability is less correlated with BI. This is similar to previous study observations, indicating that the wearability of the device, along with the perception of other people about wearable devices, significantly influences Behavioral intention to use them, though fashionability does not significantly affect it [27]. This shows the practicality aspect of users' intention that wearable devices are preferred for health care management rather than fashion sense.

All factors determining use were positively correlated with reported use, as respondents who were using wearable healthcare devices had higher mean scores than non-users. This gives an insight, that current users were happy with their product and hence were more motivated to use it. Males had a higher BI and PEOU than females. This follows a similar trend observed in the previous studies using TAM, and UTAUT models, which found females to have more difficulty learning how to operate new information technology and have lower scores of PEOU or higher scores of perceived difficulties [25–27]. The authors discussed the social context behind this, and they had hoped that this gap would reduce in the internet age. This may apply to India, but the Indian demographic may be more susceptible to lingering effects of gender disparity, opportunity, and exposure. Differences in other factors were non-significant. While wearable devices are more common among females, there is a mutually constitutive relationship between gender and technology, which in turn is adapted by technological transformations. It also means that societies with better gender equality also have a better digital economy.

Our study findings show an interesting trend where adults aged more than 25 years showed higher BI and infotainment. This may reflect changing perceptions around wearables for personal health management and fitness among older adults in India. This gives further reason for supporting the adoption of wearables as a cost-effective means of monitoring physical activity and maintaining general health.

The original TAM model pilot study used a 10-question item construct to measure PU and PEOU. This model was abbreviated in the present study to three questions per domain. The original UTAUT study used measures of performance expectancy, effort expectancy, and social influence that act on behavioral intention, which determines usage. Performance expectancy is a similar construct to PU, and effort expectancy to PEOU in TAM. Social norms in TAM2 have been seen to be similar to social influence in UTAUT. The study included three-question items similar to those used in the final UTAUT question construct, which was formulated to ensure the highest object loading and degrees of freedom according to psychometric theories, which may compromise content validity due to insufficient representation of the content [26,27].

Privacy remains a major point of concern for consumers interested in wearable healthcare devices. In particular, the release of personal information and data for analysis carries the risk of dissemination, leak, and unauthorized use [34–36]. A distinct challenge that arises in India is the heterogeneity in the availability and quality of devices. Consumer devices are not subjected to regulatory frameworks and rigorous testing that medical devices typically undergo, which poses concerns about the validity of device recordings and data security concerns. The worldwide wearable devices market ballooned in 2014 and has since resulted in a plethora of device types with different sensors, software, and design that have entered the Indian market as well. This adds additional factors that contribute to the acceptance and usage of devices, including the type and accuracy of sensors, the complexity

of the user interface, and brand value perception. Only a few brands have been used and validated in formal research studies. Researchers have developed a comprehensive device evaluation tool that may be used to guide future regulatory policies [37]. Another challenge is the high attrition rate and fall in the usage of wearable devices over time. A 2016 survey found that 30% of users of a popular brand name fitness tracker discontinue use within 6 months [38]. A 2019 study found that 20% of users abandoned their devices, with the most common reasons cited to be related to data literacy, or device comfort [39]. Age and limited technology literacy, with issues related to perceived measurement inaccuracy, have been seen to be major factors for device abandonment, and pose a significant challenge to behavioral change and long-term healthcare management goals [40,41]. Behavioral change techniques (BCT) such as just-in-time adaptive interventions, for example, motivational mobile messages accompanying device notifications and gamification, have been seen to be effective at increasing physical activity and may help solidify behavioral changes [42,43].

#### *4.4. Limitations*

The survey was primarily circulated among professionals interested in technology and personal healthcare technology, and this may be a source of sampling bias. Since we only examined a narrow subset of the population in the context of India, the generalizability and interpretation cannot be extrapolated to other contexts as in different countries or different social backgrounds. Although we compared differences across gender and age groups, we did not look into and compare differences across income groups. Moreover, all questionnaire responses are self-reported, and reflect subjective perceptions about factors and therefore may be subject to interpretation bias by participants. This is a questionnaire survey, hence cannot elicit development, use, or loss to attrition of wearable healthcare devices use, which has been elucidated in multiple previous studies [23,24]. Hence, conducting longitudinal studies will better address the issue of factors determining long-term use. Our model is constructed based on the TAM and TTF models. Although aspects of privacy calculus theory such as hedonic motivation, performance expectancy, etc. can be equated to similar measures used in TAM and TTF, it does not include the privacy calculus model, which also addresses concerns regarding personal health data security and privacy.

#### **5. Conclusions**

The use of wearable healthcare device usage has skyrocketed in India over the past few years. This is important for the medicine and healthcare industry because wearable devices play an important role in monitoring and preventing chronic diseases to a certain level. In a developing country such as India, diseases and hospitalization make a major impact on the financial status of the family, in turn affecting their quality of life. The present study helps in filling the significant research gap of studies looking at the adoption and acceptance of wearable devices in the context of a low-middle-income country.

**Supplementary Materials:** The following supporting information can be downloaded at: https:// www.mdpi.com/article/10.3390/jcm11237019/s1. Use of Wearable Health Care Devices by Adults in Managing Personal Health—A Questionnaire.

**Author Contributions:** Conceptualization, V.P., D.K.S., N.N. and B.M.Z.H.; methodology, B.M.Z.H., M.J.S., S.I., K.S. and G.C.; software, D.K.S., N.N., A.K., A.S. and R.P.; investigation, V.P. and D.K.S.; resources, M.J.S., S.I. and K.S.; data curation, M.J.S., S.I., K.S. and D.K.S.; writing—original draft preparation, V.P., D.K.S., K.S., G.C. and A.K.; writing—review and editing, N.N., R.P., P.C. and B.K.S.; visualization, R.P. and P.C.; project administration, N.N., B.M.Z.H. and B.K.S. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research has not received external funding.

**Institutional Review Board Statement:** This research was conducted with permission from the Institutional Ethics Committee. Data acquisition and analysis were performed with the protocols approved by the Institutional Ethical committee (ethical approval number FMIEC-94/2021). Informed consent was obtained from all the participants before the study. All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

**Informed Consent Statement:** All participants provided informed consent to participate in the survey and use their data for scientific purposes.

**Data Availability Statement:** All data and material collected are presented in the manuscript. Clarification on any matter can be made through the corresponding author.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

