[Postoperative respiratory depression following ambulatory anesthesia for abortion. Evolution of the ventilatory response to CO2 following the use of propofol alone or in association with different opioids: comparison with midazolam in the same situation].

Sixty patients, undergoing minor gynaecologic procedures, were prospectively enrolled in this randomized study. They were anaesthetized with either propofol or midazolam supplemented or not with fentanyl or alfentanil. Respiratory depression was evaluated using repeated measurements of ventilatory response to CO2 (Read's method) during the preoperative period until the second postoperative hour. No respiratory depression was observed when propofol was used alone. By contrast, midazolam alone induced a significant respiratory depression during the first postoperative hour.