Abstract

ABSTRACT: We compared the safety, efficacy, and side effects of induction of anesthesia with propofol (2.5 mg/kg), a new intravenous agent, and thiopental (4.0 mg/kg) in 62 patients in American Society of Anesthesiologists class I or II. There was no significant difference between induction times for the propofol (40.0 ± 2.0 sec) and thiopental (44.0 ± 4.0 sec) groups. Propofol administration produced a significant fall (P < .05) in systolic blood pressure (SBP), from 134.1 ± 2.6 mm Hg before injection to 128.3 ± 2.4, 118.2 ± 2.7, and 114.4 ± 2.8 mm Hg one, two, and three minutes after injection, respectively. Diastolic blood pressure (DBP) fell significantly (P < .05) during the three postinjection periods. Heart rate (HR) rose significantly (P < .05), from 78.6 ± 3.1 beats per minute before injection to 89.4 ± 3.4 beats per minute one minute after injection. In patients given thiopental, SBP fell significantly (P < .05), from 131.7 ± 2.7 mm Hg before induction to 126.4 ± 3.4 and 126.9 ± 4.0 mm Hg two and three minutes after injection, respectively. The DBP did not change significantly in the thiopental group, but the HR rose significantly (P < .05), from 73.3 ± 2.8 beats per minute before injection to 83.9 ± 3.0, 90.1 ± 2.3, and 84.2 ± 2.4 beats per minute one, two, and three minutes after injection, respectively. In 94% of patients given propofol, there were apneic periods of more than 60 seconds, compared to 50% in the thiopental group (P < .05). There was a significant difference (P < .05) between groups for the incidence of pain on injection; 31% of the patients receiving propofol had pain, compared to 3% of those receiving thiopental.