Abstract / Summary
Background: Secondary polycythemia could be found in chronic obstructive lung disease (COPD) with chronic hypoxemia and it may also raise the blood viscosity. This experiment evaluated acute alterations in oxygenation, hematocrit, arterial blood gas indicators and pulmonary artery systolic pressure, as well as documented the symptoms after therapeutic phlebotomy. Methods: The study is a quasi-experimental, single-arm, pre-pretest post-test study that took place at the Pulmonology Unit of Ayub Teaching Hospital, Abbottabad between November 2025 and March 2026. Eighty-seven COPD patients, whose hematocrit exceeded 56 percent were sampled consecutively. About 200-450 mL blood was taken out depending on the hematocrit level, and clinical status. The values of SpO 2, arterial blood gas values, and chosen symptoms were measured pre-phlebotomy and around 24-48 hours post-phlebotomy. Data were compared by use of paired statistical test SPSS 21 was used to analyze the data. Results: The mean age was 62.15 ± 4.08 years; 62 (71.3%) patients were male, 62 (71.3%) were smokers, and 56 (64.4%) had severe COPD. Mean SpO₂ increased from 73.63 ± 3.53% to 80.78 ± 2.26% (p<0.001). Hematocrit decreased from 60.05 ± 1.46% to 52.25 ± 0.99% (p<0.001), while PaO₂ increased from 51.11 ± 2.91 to 59.71 ± 2.24 mmHg (p<0.001). PaCO₂ decreased from 45.31 ± 2.08 to 40.31 ± 2.08 mmHg, while pH increased from 7.32 ± 0.02 to 7.39 ± 0.02 (both p<0.001). Pulmonary artery systolic pressure also decreased from 51.32 ± 9.23 to 44.54 ± 7.35 mmHg (p<0.001). Conclusion: Short-term patients with COPD and secondary polycythemia showed positive changes with the application of therapeutic phlebotomy. Yet, this uncontrolled before-after study is not able to determine a causal effect of treatment. There is a need to have controlled studies under standardized oxygen conditions and with extended follow-ups.