Cardiopulmonary Exercise Testing predicting postoperative morbimortality

Abstract

Introduction: Cardiopulmonary Exercise Testing (CPET) is recommended by ERS/ESTS clinical guidelines to be used as a preoperative evaluation and risk stratification before lung resection.

Aim: Evaluate risk factors in CPET for postoperative complications after lung resection surgery.

Methods: Retrospective observational study (2012-2018) of patients that underwent surgical stratification by CPET at University Hospital of Coimbra. Postoperative complications were assessed during the first 30 days or the hospital stay. Statistical analysis was performed using ROC curves and binary logistic regression using software SPSS.

Results: We enrolled 30 patients, mostly male (83.3%), age 66.5 (49-82) years, diagnosed or with the suspicion of lung cancer, FEV1 before surgery 65 (37.7-121.5)% pred, DLCO before surgery 64.7 (43.9-109.3)% pred. In the CPET, VO2max 17.15 (10.6-23.4) mL/Kg/min, VE/VCO2 Slope 33.9 (24.3-47.6) and EqCO2(VE/VCO2) at anaerobic threshold (AT) 36.5 (29.3-47). The duration of the hospitalization was 10.5 (4-90) days, the total incidence of complications was 46,7% being the most common a prolonged air leak, pneumonia, anemia, and atelectasis. Among our population, we find as a predicting factor of postoperative complications EqCO2(AT)>35 (sensitivity 100%, specificity 50%), when this variable was adjusted to age, lung function (FEV1 and DLCO) and VO2max, it remains as an independent predictor of complications (OR 1.51, 95% CI: 1.00-2.26; P 0.048).

Conclusion: CPET is a valuable tool used in the risk assessment of lung resection surgery. Despite the known VO2max stratification tool we find in our sample that the EqCO2(AT) is a predictor of complications and therefore morbimortality among our patients.