Objective: The objective of the present study was to perform longitudinal objective evaluations of recovery of exercise capacity based on expired gas analysis during exercise testing up to 1 year after pulmonary resection.
Methods: The study included 18 patients who underwent lobectomy. Expired gas analysis during exercise testing was conducted 1 week before surgery and 2 weeks, 1 month, 3 months, 6 months, and 1 year after surgery. The parameters studied included maximum exercise capacity based on expired gas analysis during exercise testing (maximum oxygen uptake per minute per square meter of body surface area) and assessment of moderate exercise capacity (anaerobic threshold per square meter of body surface area). The changes in postoperative data relative to the preoperative values (baseline) were assessed, including the percent changes from baseline data, which were arbitrarily given a value of 100.
Results: Maximum oxygen uptake per minute per square meter of body surface area decreased significantly to 78.6% +/- 14.2% of the baseline value at 2 weeks after surgery and was 80.3% +/- 12.7%, 90.9% +/- 15.9%, 90% +/- 19.7%, and 97% +/- 4.8% of the baseline value at 1, 3, and 6 months, and 1 year, respectively. Anaerobic threshold per square meter of body surface area reached 91.1% +/- 17.5% of the baseline value even 2 weeks after surgery and was 87.1% +/- 17.3%, 97.5% +/- 28.0%, 84.3% +/- 13.2%, and 104% +/- 16.2% of the baseline value at 1, 3, and 6 months, and 1 year, respectively.
Conclusion: The extent of recovery of exercise capacity at 1 year after surgery was approximately 95%. Furthermore, the anaerobic threshold per square meter of body surface area was restored to the preoperative level by 1 year after surgery.