
Peak V ˙O 2, V ˙E/ V ˙CO 2 slope, pulmonary function tests, 6-min walk distance and arterial blood gases were similar between the two groups. Area under the receiver operating characteristic (ROC) for VD was 0.81 ( p < 0.002), VD/VT was 0.68 ( p = 0.077), and PETCO 2 was 0.52 ( p = 0.840). Patients with PPC had significantly elevated resting VD compared to those without (0.318 ± 0.028 L vs. Fourteen (40%) patients had one or more PPC. In the first 2 min prior to the exercise portion of the CPET, we obtained resting VT, minute ventilation ( V ˙E), VD (less instrument dead space), VD/VT, PETCO 2, and arterial blood gases.

Patients underwent preoperative pulmonary function testing, symptom-limited CPET, and a 6-min walk test. Thirty-five consecutive patients were included in the study. The objective of this study was to prospectively determine the utility of resting measurements of VD and VD/VT in predicting PPC in patients who underwent robotic-assisted lung resection for suspected or biopsy-proven lung malignancy. Resting physiologic dead space (VD), and physiologic dead space to tidal volume ratio (VD/VT), may be a better predictor of PPC than PETCO 2. However, breath-breath breathing pattern significantly affects PETCO 2. Recently, resting end-tidal partial pressure of carbon dioxide (PETCO 2) has been shown as a good predictor for increased risk of PPC.

Cardiopulmonary exercise testing (CPET) is performed to predict risk of PPC in patients with severely reduced predicted postoperative forced expiratory volume in one second (FEV1) and diffusion of carbon monoxide (DLCO). Lung resection surgery carries significant risks of postoperative pulmonary complications (PPC).
