PROPOFOL VERSUS MIDAZOLAM FOR MONITORED SEDATION - A COMPARISON OF INTRAOPERATIVE AND RECOVERY PARAMETERS

Study Objective: To compare intraoperatize and recovery parameters in Patients who received either propofol infusion (PI), propofol bolus (P B), or midazolam bolus (MZ) for sedation. Design: Randomized clinical, study Setting: Medical/surgical patients in a specialized hospital. P atients: Ninety patients, aged 18 to 85 years, scheduled for central v enous access for chemotherapy and/or total parenteral nutrition. Inter ventions: In 30 patients, sedation was induced with MZ 0.02 mg/kg intr avenously (IV), repeated every 2 to 3 minutes to achieve a sedation le vel of 3 (eyes closed, responds to verbal stimulus (SL3). Maintenance was with MZ 0.005 mg/kg IV, repeated as necessary to maintain SL3. In both propofol groups (30 patients each), induction of sedation was wit h a bolus of propofol 0.75 to 1.0 mg/kg IV. Maintenance in the PB grou p was with propofol 0.25 mg/kg IV, repeated as necessary to maintain S L3. Maintenance in the PI group was with propofol 2 to 4 mg/kg/hr or 3 3 to 66 mug/kg/min to maintain SL3. Measurements and Main Results: Blo od pressure, heart rate, respiratory rate, oxygen saturation, and seda tion level were monitored each minute for 5 minutes and then at 5-minu te intervals during the procedure. A right atrial blood sample was tak en for pH and partial pressure of carbon dioxide at maximum sedation. Adequate sedation was achieved in all three groups. The time to reach SL3 was significantly shorter in the PB group than in the PI and MZ gr oups (p < 0.05 and p < 0.01, respectively). Cardiovascular and respira tory parameters were remarkably stable. Immediate recovery, as judged by spontaneous eye opening, response to commands, and ability to state date of birth, was significantly shorter in both the PB and PI group, than in the MZ group (p < 0.0001). Intermediate recovery, as measured by sedation score at recovery entry, Aldrete score, and time to stand ing, was slower in the MZ group (p < 0.05 for the MZ group vs. the PB and PI groups for sedation score and Aldrete score; p < 0.05 for the M Z group vs. the PI group in time to standing). Psychomotor recovery, j udged by digit symbol substitution tests, was significantly faster in the PB and PI groups (p < 0.05 vs. the MZ group). Amnesia, measured by picture recall, was significantly greater in the MZ group than in the PI and PB groups (p < 0.05). Mood changes were measured on a visual a nalog scale. All groups showed improvement. Nausea, headache, dizzines s, blurred vision, appetite, tension, pain, depression, drowsiness, an d ability to concentrate were evaluated in the preoperative and postop erative period. The frequency did not differ significantly between gro ups due to confounding factors such as postoperative chemotherapy and premedicant drugs. Conclusion: The PI, PB, and MZ groups all gave exce llent sedation for patients undergoing surgical procedures with local anesthesia. Amnesia was greater with midazolam, and recovery was more rapid with propofol.