Hemodynamic and oxygen consumption changes following general anesthesia were studied in 11 patients who did and in 11 patients who did not received droperidol at the end of operation. Both group were similar with respect to age, duration of anesthesia, doses of anesthetic drugs, and hemodynamic and oxygen consumption values immediately at the end of operation. The highest oxygen consumption measurements which were selected as representative of the maximal metabolism of the recovery period showed that the following parameters were lower in the droperidol group than in the non-droperidol group: oxygen consumption (162 +/- 12 and 238 +/- 19 ml/min/m2 respectively), cardiac index (3.0 +/- 0.2 and 4.4 +/- 0.4 l/min/m2), mean arterial pressure (11 +/- 6 and 129 +/- 5 torr), stroke index (27 +/- 3 and 46 +/- 4 ml/m2) left ventricular stroke work index (38 +/- 5 and 77 +/- 8 gm/m2) and PaCO2 (39 +/- 2 and 49 +/- 2 torr). The measurements performed after extubation were similar in both groups. These data show a metabolic and hemodynamic stabilizing effect of droperidol during recovery which may be useful in high-risk patients.