The Interpretation of Carbon Monoxide Diffusing Capacity Test Depending of Hemoglobin Concentration

The carbon monoxide diffusion capacity (DLCO) is among others dependent of the hemoglobin value. The result of DLCO test in patients with anemia change when we adjust DLCO for hemoglobin (Hb) concentration. The aim of the study was to estimate if the differences between result of DLCO and DLCO/VA before and after adjust the Hb value can change the interpretation of the test in the group with normal and low value of Hb. The study group consist of 25 patients with normal level of Hb (group A) and 21 ones with anemia (group B). All studied have been done spirometry, bodypletyzmografy and DLCO test. All tests were made on the SensorMedics. The DLCO test was made in the single breath diffusing capacity program Results. The values of the Hb in the group A were above 13 g/dl for female and 14 g/dl for man. In the group B the Hb value were less then 10 g/dl. In the group A the middle Hb concentration was 14.49 ± 1.36 g/dl. DLCO and DLCO/VA before and after Hb value adjusted were 91.4 ± 17.98 vs. 90.7 ± 17.58% i 101.5 ± 19.46 vs. 100.7 ± 18.65% (p > 0.05) In the group B the middle Hb concentration was 8.77 ± 0.97 g/dl. DLCO and DLCO/VA before and after Hb value adjusted were: 57.05 ± 17.55 vs. 72.19 ± 25.27% i 67.57 ± 11.18 vs. 84.66 ± 14.62% (p < 0.05). Conclusions: 1. The were non statistically important change in the DLCO test results after consideration on Hb level in the studied group without anemia, so in the patients with normal level of Hb the DLCO test result doesn’t change the interpretation of the test after the consideration on Hb concentration. 2. In patients with anemia we shout adjust the Hb value to the DLCO test because the results with out this can completely change the interpretation of the test and clinical diagnosis.