Comparison of gas exchange after lung resection with a Boussignac CPAP or Venturi mask

Methods. The study population comprised 110 patients undergoing LRS. On arrival in the postanaesthesia care unit (PACU), patients were randomized to receive CPAP at 5–7 cm H2O during the first 6 h after surgery (CPAP group) or supplemental oxygen through a Venturi mask (Venturi group). The PaO2 /FIO2 ratio was measured on arrival in the PACU, 7 h after admission, and the day after surgery. The PaO2 /FIO2 ratio is the primary endpoint of our study. We also analysed the chest radiograph and assessed the postoperative course. We then analysed the impact of ventilatory management in the PACU depending on the respiratory risk of the patient. Results. Baseline characteristics were similar in both groups. Patients who received CPAP had significantly higher PaO2 /FIO2 at 24 h after surgery compared with patients managed conventionally (Venturi group) (48.6+14 vs 42.3+12, P¼0.031), but there were no differences at 7 h. On subgroup analysis, we found that the benefits of CPAP were greater in higher risk patients. The incidence of postoperative pulmonary complications and stay in the PACU and hospital were similar in both groups. Conclusions. In patients undergoing LRS, prophylactic CPAP during the first 6 h after surgery with a pressure of 5–7 cm H2 Oi mproved thePaO2 /FIO2ratio at 24 h. This effect was more evident in patients with increased risk of postoperative pulmonary complications.