Redefining the lowest exercise peak oxygen consumption acceptable for lung resection of high risk patients

Purpose: We have demonstrated that patients with resectable lung cancer, but at high risk for complications because of severe lung dysfunction, can safely undergo surgical intervention if they reach values of V̇O_2Peak≥15ml/ Kg/min during preoperative exercise testing. Further analysis of our experience indicates that there have been patients with V̇O_2Peak<15ml/Kg/min who survived surgical treatment. All survivors, however, had V̇O_2Peak that, when adjusted for height, sex, and age, were ≥50% of maximum predicted. We propose that defining the "safe" lowest level of V̇O_2Peak based on percent predicted V̇O_2Max, rather than an absolute value, would maximize the number of high risk patients that would benefit from surgical treatment. Methods: We performed exercise testing on 123 patients with resectable lung cancer at high risk for surgery because of:1)FEV₁≤40%, 2) pCO₂≥45 mmHg, or 3) radionuclide estimated postresection FEV₁≤33%. Patients with V̇O_2Peak ≥50% of maximum predicted were offered surgical treatment. Results: Forty-six of 123 patients reached V̇O_2Peak≥50% and had lung resection. There was no surgical mortality. Five had complications (pneumonia,atelectasis, prolonged air leak). Forty-three were extubated within 24 hrs. Median hospital stay was 8.2 days. Conclusions: Preoperative exercise testing based on 50% percent of predicted V̇O_2Max is useful in redefining the lowest "safe" selection criteria for lung resection in patients with severe lung dysfunction. Clinical Implications: One-third of patients with resectable lung cancer deemed inoperable by conventional pulmonary criteria can safely undergo lung surgery after preoperative selection by exercise testing. Grant support: Mary L.E. McConnell Fund for Lung Research.