Search Results (147)

Background: Patient-controlled analgesia (PCA) is widely used for postoperative pain control after total knee arthroplasty (TKA). Although postoperative nausea and vomiting (PONV) has been extensively studied, early discontinuation of PCA—representing failure to sustain an opioid-based analgesic strategy—has not been adequately investigated as a distinct, decision-relevant outcome. Methods: We conducted a single-center retrospective observational study of 1188 patients undergoing primary TKA who received PCA for postoperative pain management. The primary aim was to develop interpretable machine learning models for predicting early PCA discontinuation using routinely available perioperative variables. A secondary aim was to evaluate the incremental predictive value of hierarchical feature sets reflecting progressively available clinical information. Results: Early PCA discontinuation occurred in approximately 10% of patients, reflecting a relatively low-frequency clinical event associated with class imbalance. Female sex and PONV-related susceptibility factors, including prior nausea/vomiting intolerance, were more common among patients with early PCA discontinuation. The random forest Step 3 model demonstrated acceptable discriminative performance (AUC: 0.77; PR-AUC: 0.38), good calibration accuracy (Brier score: 0.065), and favorable clinical utility on decision curve analysis. Explainable analyses showed that patient-level susceptibility factors—such as prior intolerance to nausea or vomiting and baseline clinical characteristics—contributed more strongly to early PCA discontinuation than perioperative management or procedural variables. Conclusions: Early PCA discontinuation after TKA represents a distinct, decision-based clinical endpoint that is not captured by symptom-focused outcomes such as PONV. Interpretable machine learning models may help identify patients at increased risk of early PCA discontinuation after TKA, which may support informed counseling and proactive planning of individualized postoperative pain management strategies. However, external validation is required before routine clinical implementation. Full article

Background/Objectives: In our previous study, we reported that postoperative flexion ≥ 120° is associated with better knee function after TKA, whereas flexion gain is associated with higher patient satisfaction. However, preoperative determinants of achieving these clinically relevant targets remain unclear. This study investigated preoperative factors predicting (1) postoperative flexion ≥ 120° and (2) clinically meaningful flexion gain after TKA. Methods: We retrospectively reviewed prospectively collected data from 221 primary TKAs (171 patients) performed between 2014 and 2020. Passive knee range of motion (ROM) was measured preoperatively and at 1 year postoperatively. Preoperative variables included age, sex, body mass index (BMI), Pain Catastrophizing Scale, Knee Society Score, and Knee Injury and Osteoarthritis Outcome Score (KOOS). Patients were categorized as the good-flexion group (postoperative flexion ≥ 120°) or poor-flexion group (<120°), and as the improvement group (flexion gain ≥ 5°) or no-improvement group (<5°). Variables differing between groups were entered into multivariable logistic regression. Receiver operating characteristic (ROC) analysis (Youden index) identified optimal cutoffs. Results: Postoperative flexion was ≥120° in 63.3% of knees, and flexion gain ≥ 5° occurred in 48.4%. In multivariable models, preoperative flexion angle was the only independent preoperative predictor of achieving postoperative flexion ≥ 120° (p < 0.001) and flexion gain ≥ 5° (p < 0.001). ROC analysis showed that a preoperative flexion cutoff of 120° best discriminated both outcomes (AUC 0.78 for postoperative flexion ≥ 120°; AUC 0.80 for flexion gain ≥ 5°). Conclusions: A 120° preoperative knee flexion threshold provides a simple, clinically actionable marker for predicting postoperative flexion ≥ 120° and meaningful flexion gain after TKA. Incorporating preoperative flexion into shared decision-making may improve counseling by setting realistic expectations for postoperative knee function and satisfaction. Full article

Background: The primary goal of root canal treatment is the prevention and healing of apical periodontitis through the meticulous elimination of pathogenic bacteria and infected tissues. Within this framework, apical patency remains a fundamental yet debated clinical concept. Objectives: This review aims to evaluate the clinical significance of maintaining apical patency, its influence on postoperative discomfort, and the technical strategies required for predictable negotiation. Methods: We performed a comprehensive review of existing literature, including clinical studies and recent meta-analyses, focusing on the correlation between patency maneuvers and postoperative pain, the role of preoperative CBCT imaging, and the efficacy of specialized negotiation instruments and motor kinematics. While patency facilitates thorough debridement, evidence regarding its impact on postoperative pain is conflicting, with recent meta-analyses suggesting it may actually alleviate discomfort intensity. Preoperative CBCT was identified as essential for identifying complex anatomy, such as the MB2 canal. Furthermore, the use of specialized files and reciprocating motor modes enhances the predictability of glide path establishment. Conclusions: Although failure to achieve patency does not always dictate a negative outcome, it is associated with improved long-term healing. Clinicians should prioritize “Anatomical Patency”—respecting original morphology—over forceful “Operative Patency” to ensure procedural integrity and clinical success. Full article

Background: Osteoporotic vertebral compression fractures (OVCFs) are among the most 11 common fragility fractures in the elderly. Although vertebroplasty and kyphoplasty provide effective pain relief, new vertebral fractures remain a significant concern postoperatively. Imaging parameters associated with sarcopenia and systemic inflammatory markers have been individually associated with fracture risk, but their combined predictive value in the postoperative period has not been adequately defined. Methods: This retrospective cohort study included 166 patients who underwent vertebroplasty or kyphoplasty for OVCFs with a follow-up period of at least 12 months. Cross-sectional area (CSA) and density (HU) of the Psoas muscle were measured at the L3 mid vertebral level on preoperative CT. Preoperative hematological indices (NLR, PLR, LMR, SII, lymphocyte count, hemoglobin, and MPV) were recorded. The primary outcome was the development of a new vertebral fracture. Group comparisons were performed using Mann–Whitney U tests with Benjamini–Hochberg correction. Logistic regression identified independent predictors. Internal validation was performed using bootstrap optimism correction (1000 iterations) and 10-fold cross-validation. Calibration was assessed using the Hosmer–Lemeshow test and calibration plots. Results: Forty-nine patients (29.5%) developed a new fracture. After multiple comparison correction, Psoas 25 HU (BH-adj p < 0.001, r_rb = −0.810), Psoas CSA (BH-adj p < 0.001, r_rb = −0.622), NLR (BH-adj p = 0.016), lymphocyte count (BH-adj p = 0.009), and hemoglobin (BH-adj p = 0.033) showed significant differences between groups. SII did not remain significant after multiple-comparison correction (BH-adjusted p = 0.092). In multivariate logistic regression, only Psoas CSA (OR = 0.403, 95% CI 0.230–0.708, p = 0.002) and Psoas HU (OR = 0.825, 95% CI 0.770–0.885, p < 0.001) remained independently significant. The parsimonious model, with adequate calibration (Hosmer–Lemeshow p = 0.524), achieved an optimism-adjusted AUC of 0.918 (10-fold CV AUC = 0.924). A Psoas HU threshold of 20.50 yielded 79.6% sensitivity and 94.9% specificity. Conclusions: CT-derived Psoas muscle mass and quality are strongly associated with new vertebral fractures after percutaneous vertebral augmentation procedures in this retrospective cohort and showed stronger independent predictive performance than systemic inflammatory markers. These readily accessible imaging biomarkers can aid in risk stratification, although the proposed threshold requires externally validation before clinical implementation. Full article

Introduction: Chronic subdural hematoma (CSDH) is a complex disease with an overall incidence of 1.7–20.6 per 100,000 persons per year and is more commonly encountered in the elderly population. It is projected to be one of the most common neurosurgical procedures. Postoperative delirium is a common complication associated with the elderly, causing increased morbidity and prolonged hospital stay. However, its risk factors in chronic subdural hematoma patients have not been well studied. Methods: A total of 202 consecutive patients with chronic subdural hematoma at different neurosurgical centers in Europe between January 2023 and June 2025 were enrolled. Various clinical indicators were analyzed to identify independent risk factors for postoperative delirium using univariate and multivariate regression analyses. Results: Out of the 202 patients (age, 71 (IQR, 18); female-to-male ratio, 1:2.7) studied, 63 (31.2%) experienced postoperative delirium. Univariate analysis identified age (p < 0.001), gender (p = 0.014), restraint belt use (p < 0.001), electrolyte imbalance (p < 0.001), visual analog scale (VAS) pain score (p < 0.001), hematoma thickness (p < 0.001), midline shift (p < 0.001), hematoma side (p = 0.013), hematoma location (p = 0.018), and urinal catheterization (p = 0.028) as significant factors. Multivariate regression analysis confirmed the significance of restraint belt use (B = 7.657, p < 0.001), electrolyte imbalance (B = −3.993, p = 0.001), VAS pain score (B = 2.331, p = 0.016), and midline shift (B = 0.335, p = 0.007). Hematoma thickness and age had no significant impact. Conclusions: Increased midline shift and VAS pain scores, alongside restraint belt use and electrolyte imbalance, elevate delirium risk in chronic subdural hematoma surgery. Our prediction models may offer a reference value in this context. Full article

Radiological classification systems are widely used to estimate the difficulty of mandibular third molar extraction, yet their ability to predict patient-centered outcomes remains uncertain. This study investigated whether radiological predictors of surgical difficulty are associated with prolonged operative time and increased postoperative pain, and whether the association between radiological parameters and postoperative pain changes after adjustment for operative time. In this exploratory secondary analysis of a randomized clinical trial, 122 patients undergoing mandibular third molar extraction were evaluated using the Winter and Pell–Gregory classifications and the Pederson difficulty index. Surgical duration was recorded, and postoperative pain was assessed during the early postoperative period using a numeric rating scale. Multivariable regression analyses were applied to identify independent predictors of operative time and postoperative pain. Horizontal and mesioangular impactions were associated with significantly longer operative times. Surgical duration was independently associated with higher postoperative pain (β = 0.03 per minute; R² = 0.22). Importantly, radiological parameters were no longer significant after adjustment for operative time. These findings indicate that the association between radiological complexity and postoperative pain is not independent of operative time and should be interpreted as reflecting shared variance between these factors rather than a direct relationship. Full article

Background/Objective: Postoperative recovery after spine surgery varies substantially and cannot be fully explained by structural pathology alone. This study evaluates postoperative outcomes using a structured 2 × 2 Surgical Trauma Gradient integrating exposure-related invasiveness (minimally invasive vs. open) and biomechanical strategy (decompression vs. fusion), and examines the modifying role of Type-D personality. Methods: This observational cohort study included 200 patients undergoing elective spine surgery. Patients were stratified into four surgical subgroups: minimally invasive decompression, open decompression, minimally invasive fusion, and open fusion. Primary outcomes included pain intensity (Visual Analog Scale), functional disability (Oswestry Disability Index), patient satisfaction (Patient Satisfaction Index), and postoperative complications at 12-month follow-up. Surgical invasiveness was modeled both categorically and as an ordinal gradient. Multivariable regression, logistic regression, interaction analysis, and longitudinal mixed-effects models were applied. Results: Postoperative outcomes demonstrated a consistent gradient across increasing surgical burden. In multivariable models, higher surgical invasiveness independently predicted greater residual pain (β = 0.69; 95% CI 0.55–0.82; p < 0.001) and higher functional disability (β = 6.20; 95% CI 5.10–7.30; p < 0.001). Increasing invasiveness was also associated with lower patient satisfaction (β = −0.38; 95% CI −0.47 to −0.29; p < 0.001) and higher complication risk (OR = 1.64; 95% CI 1.12–2.41; p = 0.01). Type-D personality independently predicted worse postoperative pain (β = 0.41; p = 0.008) and significantly modified the association between surgical burden and pain (interaction β = 0.22; p = 0.012). Conclusions: Postoperative outcomes follow a structured Surgical Trauma Gradient influenced by both surgical burden and psychosocial vulnerability, particularly Type-D personality. Integrating these dimensions may improve perioperative risk stratification and support individualized treatment strategies. Full article

Background: While providing enough sedatives to avoid pain and trauma during surgery is important, studies show a link between the received sedatives and the development of postoperative delirium (POD). Therefore, predicting POD from clinical or physiological data before or during surgery is highly advantageous. This capability enables healthcare providers to proactively implement necessary measures, thereby mitigating or preventing potential complications. Methods: In this study, we focus on patients with Parkinson’s disease undergoing deep brain stimulation surgery who are particularly susceptible to POD. We investigate what aspects of EEG’s power, functional connectivity and complexity during the course of the surgery are influenced by the amount of sedative. Furthermore, we aim to determine whether and to what extent the recorded brain activity during surgery can serve as a reliable means for the prediction of POD in this group of patients. Results and Conclusions: Our results show significant correlations between various power, connectivity and complexity features of EEG and the amount of sedatives. Even though single EEG features are not significantly different between the two groups who either developed or did not develop POD, we show that a classifier based on support vector machines using the selected EEG features could predict POD. Furthermore, our results provide evidence that a classifier trained only on the amount of sedatives is unable to predict POD. Accompanying this paper, our code is published as an open-source toolbox for the analysis of the EEG signal recorded with the four-channel SEDLine Root system, which is among the widely used EEG systems in operation rooms and its recorded data come with challenges that are addressed in our toolbox. Full article

Acute postoperative pain remains a major clinical challenge, affecting both recovery and resource utilisation. Beyond nociceptive input, pain is shaped by cognitive and emotional factors, including patient expectations. This narrative review examines the role of expectations in perioperative pain modulation, framed within predictive coding and Bayesian inference models. These models conceptualise pain as a probabilistic process that integrates sensory input with prior expectations, weighted by precision. In theory, positive expectations may enhance analgesic efficacy, whereas negative expectations may amplify pain via nocebo mechanisms. Control modifies expectations and may reduce perceived pain, while uncertainty diminishes these benefits. Evidence from observational studies links preoperative pain self-efficacy and anticipated pain scores to postoperative outcomes, yet interventional trials remain scarce. In this narrative review, we propose that expectation-sensitive strategies, including structured communication and computational modelling, may inform individualised anaesthesia and analgesia. Future research should validate these frameworks in clinical trials, optimise preoperative expectation management, and explore synergistic approaches that combine pharmacology with cognitive modulation. Understanding and leveraging expectations may offer a promising conceptual direction for more individualised perioperative care, although this approach remains hypothesis-generating at present. Full article

Introduction: Artificial intelligence (AI) and robot-assisted platforms are increasingly influencing cardiothoracic surgery. AI enhances risk prediction, imaging interpretation, and early complication detection, while robotics improves visualization, dexterity, and minimally invasive access. This systematic review evaluates the current evidence supporting these technologies and their implications for clinical practice. Methods: A systematic literature search was conducted across PubMed, Embase, Scopus, Web of Science, and Google Scholar (January 2000–May 2025) following PRISMA 2020 guidelines. After screening and eligibility assessment, 67 studies met predefined inclusion criteria and were incorporated into the qualitative synthesis. Additional high-impact reviews and consensus documents were consulted for contextual interpretation. Results: Machine learning models demonstrated modest but consistent improvements in predictive performance compared with EuroSCORE II and STS scores, particularly in high-risk cohorts. Robot-assisted mitral and coronary procedures showed reduced postoperative pain, blood loss, ICU stay, and recovery time in experienced centers, though early learning phases were associated with longer operative, cross-clamp, and bypass times. AI-enabled intraoperative tools, such as video analysis, workflow recognition, and real-time anatomical segmentation, emerged as promising adjuncts for surgical precision. Structured robotic training programs, especially simulation-based and dual-console pathways, accelerated proficiency acquisition. Conclusions: AI and robotic systems act as augmentative technologies that enhance rather than replace the surgeon’s role. Their safe and effective adoption requires standardized training, transparent AI decision pathways, and clear ethical and medico-legal governance. Full article

Objective: The objective of this study was to choose the optimal anesthesia method for gastric cancer patients undergoing surgery with lymph node dissection. Materials and Methods: The study included 53 patients with stage T1-4aN0-3M0 gastric cancer, who underwent radical surgery with xenon and dexmedetomidine (DMM) anesthesia in combination with epidural analgesia (main group, 27 patients) or with sevorflurane anesthesia in combination with epidural analgesia (comparison group, 26 patients). All patients underwent monitoring of hemodynamic parameters, blood coagulation system, thromboelastometry, and inflammation and metabolic parameters (interleukins, hormones and glucose levels), with an assessment of complications according to the Clavien-Dindo classification and the intensity of postoperative pain. Results: Awakening and extubation times, narcotic analgesic consumption, and Numeric Rating Scale pain scores were lower in the xenon + DMM group than in the sevoflurane group (p < 0.05). The overall number of patients experiencing complications did not differ significantly between anesthesia types; however, significant differences were found in the total number of complications (p = 0.003), the number of complications according to Clavien-Dindo I (p = 0.043) and II (p = 0.019), and the incidence of postoperative nausea and vomiting (p = 0.042). Conclusions: The BIS monitoring data obtained showed a sufficient level of anesthesia depth during surgery in both groups; however, post-anesthesia depression persisted longer in patients in sevoflurane group. Mathematical models for predicting Clavien-Dindo IIIb-V complications and severe postoperative pain syndrome are characterized by high sensitivity and specificity. They include simple clinical and laboratory parameters as well as type of anesthesia as predictors. The limitations of predictive models are also discussed in the article. Full article

Background/Objectives: Post-cholecystectomy syndrome (PCS) remains diagnostically challenging due to overlapping biliary and non-biliary causes. This study aimed to evaluate whether common bile duct (CBD) diameter measured by MRCP can serve as a practical triage parameter in symptomatic PCS patients and to define a data-supported threshold for predicting clinically relevant biliary pathology. Secondary objectives included assessing correlations between MRCP findings and upper endoscopic features. Methods: In this retrospective single-center study, symptomatic adults undergoing upper endoscopy and MRCP were analyzed. Demographic, clinical, biochemical, radiologic, and endoscopic variables were recorded. Diagnostic performance was assessed using ROC analysis, and independent predictors of biliary dilatation were evaluated with multivariable logistic regression. Results: We analyzed 141 symptomatic post-cholecystectomy patients (mean age 58.2 ± 16.3 years; 67.4% female; median time since surgery 18 [9–36] months). Major symptoms: abdominal pain 84.9%, dyspepsia/bloating 47.5%, nausea/vomiting 22.3%, diarrhea 15.1%. CBD diameter measurements were available in the MRCP subgroup (n = 45); ERCP was performed selectively (n = 12). MRCP findings: CBD ≥ 7 mm 31.9%, biliary dilatation 14.9%, stricture 2.8%, suspected Oddi dysfunction 11.3%, postoperative complications 39.7%. Endoscopy: mucosal inflammation 91.5%; normal 8.5%. Significant correlations included CBD diameter vs. mucosal inflammation (r = 0.32, p = 0.001), dilatation vs. bile reflux (r = 0.28, p = 0.004), and Oddi dysfunction vs. papillary edema (r = 0.41, p = 0.001). CBD diameter showed the best diagnostic performance (AUC 0.82, 95% CI 0.74–0.90; cut-off ≥ 8.0 mm; sensitivity 78.3%; specificity 81.5%; p < 0.001). In multivariable analysis, age independently predicted biliary dilatation (OR 1.05 per year; 95% CI 1.01–1.09; p = 0.007). Conclusions: In symptomatic post-cholecystectomy patients, MRCP-measured CBD diameter provides a useful metric for risk stratification, with a threshold of ≥8 mm identifying patients more likely to harbor biliary pathology. These findings support a structured diagnostic approach that prioritizes noninvasive imaging while reserving ERCP for selected cases. Further prospective validation is warranted. Full article

Background/Objectives: Meloxicam (MLX) is a nonsteroidal anti-inflammatory drug (NSAID) recommended for treating acute and chronic pain in dogs, frequently administered prophylactically to mitigate postoperative pain; however, its utility is limited by characteristic NSAID-associated adverse effects, such as gastrointestinal side effects. Nanosystems offer the potential to minimize adverse effects by sustaining drug release. Therefore, this study assessed the pharmacokinetics of MLX nanoencapsulation in female dogs undergoing ovariohysterectomy using a population pharmacokinetic (PopPK) modeling approach. Methods: MLX-loaded polymeric nanocapsules (NC-MLX) were prepared using the nanoprecipitation method and characterized by zeta potential, pH, mean diameter, particle size distribution, and drug content. Dogs received 0.2 mg/kg of either NC-MLX or free MLX orally, 4 h before surgery, and plasma samples were analyzed using an HPLC-PDA method. Pharmacokinetics were characterized by non-compartmental analysis and PopPK modeling. Several compartmental structures, variability models, and residual error models were explored, and relevant covariates were investigated. Results: NC-MLX had an average diameter of 326 ± 13 nm, a zeta potential of −26.2 ± 6.4 mV, and drug loading of 99.47% ± 0.01%. NC-MLX showed a significant increase in the t_1/2 (36.99 ± 17.26 h) of MLX compared to the free drug (15.22 ± 4.4 h). The best-fitting PopPK model was a two-compartment model with double extravascular first-order absorption rate constants (Ka₁ and Ka₂), including a lag time for Ka₂ and linear elimination, describing the second peak observed in several animals. The nanoformulation was a significant covariate for Tlag₂, delaying the time for absorption (1.22 and 2.55 h for free MLX and NC-MLX, respectively) and increasing V₂ (0.134 and 0.402 L/kg for free MLX and NC-MLX, respectively). External model validation showed that the final PopPK model accurately predicted plasma concentrations, with MPE% and RMSE values below 15%. Conclusions: Our findings suggest that NC-MLX alters MLX absorption and distribution profiles, supporting its potential as an alternative for postoperative pain management in dogs. Full article

Remimazolam is an ultra-short-acting benzodiazepine developed according to the “soft drug” concept and characterized by rapid onset, predictable offset, organ-independent metabolism, and the availability of a specific antagonist. Due to these pharmacological features, this drug represents a particularly attractive option for pediatric anesthesia and sedation, a field in which traditional agents are often limited by hemodynamic instability, prolonged recovery, and adverse respiratory effects. This narrative review summarizes and discusses the current evidence regarding the use of remimazolam in pediatric patients, focusing on pharmacokinetics, pharmacodynamics, clinical applications, and safety. Available data indicate that remimazolam provides effective sedation and anesthesia in children across multiple settings, including induction of general anesthesia, non-operating room anesthesia, and intensive care unit sedation. Compared with propofol and midazolam, remimazolam is generally associated with greater hemodynamic stability, rapid recovery, reduced emergence delirium, and a favorable respiratory profile, while maintaining comparable efficacy. Intranasal administration has also shown promise as a premedication strategy for reducing preoperative anxiety, although it may occasionally be associated with pain. Even if remimazolam lacks intrinsic analgesic properties, its use appears to indirectly improve postoperative comfort by attenuating stress responses and emergence agitation. Despite encouraging results, pediatric use of remimazolam remains off-label in many countries, and evidence is still limited by small sample sizes and heterogeneous protocols. Further large-scale randomized controlled trials are needed to define optimal dosing strategies, long-term safety, and their definitive role in pediatric anesthetic and sedative practice. Full article

Background/Objectives: To evaluate the clinical and MRI characteristics of benign solitary schwannomas of the extremities, compare pre- and postoperative neurological symptoms, and identify preoperative and intraoperative risk factors for postoperative complications. Methods: A retrospective review was conducted on 47 patients with histopathologically confirmed benign solitary schwannomas of the extremities who underwent surgical excision. Demographic data, MRI characteristics (tumor volume, perilesional edema, and degenerative changes such as cystic components or intratumoral hemorrhage), fascicular relationship, and use of tru-cut biopsy were recorded. Pre- and postoperative neurological symptoms were compared. Univariate logistic regression analysis was performed to identify factors associated with postoperative complications. Results: The mean age was 38.6 ± 15 years, and the mean follow-up period was 109.8 ± 65.1 months. Lesions were predominantly located in the upper extremity (65.9%), with a mean volume of 9.6 ± 4.8 cm³; perilesional edema and/or degenerative changes were present in 53.1% of cases. Postoperative complications occurred in 19.1% of patients, with intrafascicular involvement being a significant predictor (OR = 5.4, p = 0.037) and a positive preoperative Tinel’s sign showing a trend toward significance (OR = 4.2, p = 0.084). Tumor volume, perilesional edema, degenerative changes, tru-cut biopsy, and anatomical location were not significantly associated with complications. At final follow-up, pain remission was 82.1%, and paresthesia improvement was 63.6%. Conclusions: Intrafascicular involvement was associated with postoperative complications in univariate analysis, whereas preoperative MRI characteristics, biopsy, and Tinel’s sign showed no predictive value for postoperative risk. Full article