Sedative Efficacy of Propofol in Patients Intubated/Ventilated after Coronary Artery Bypass Graft Surgery

BACKGROUND: Sedation after open heart surgery is important in preventing stress on the heart. The unique sedative features of propofol prompted us to evaluate its potential clinical role in the sedation of post-CABG patients. OBJECTIVES: To compare propofol-based sedation to midazolam-based sedation after coronary artery bypass graft (CABG) surgery in the intensive care unit (ICU). PATIENTS AND METHODS: Fifty patients who were admitted to the ICU after CABG surgery was randomized into two groups to receive sedation with either midazolam or propofol infusions; and additional analgesia was administered if required. Inclusion criteria were as follows: patients 40-60 years old, hemodynamic stability, ejection fraction (EF) more than 40%; exclusion criteria included patients who required intra-aortic balloon pump or inotropic drugs post-bypass. The same protocol of anesthetic medications was used in both groups. Depth of sedation was monitored using the Ramsay sedation score (RSS). Invasive mean arterial pressure (MAP) and heart rate (HR), arterial blood gas (ABG) and ventilatory parameters were monitored continuously after the start of study drug and until the patients were extubated. RESULTS: The depth of sedation was almost the same in the two groups (RSS=4.5 in midazolam group vs 4.7 in propofol group; P = 0.259) but the total dose of fentanyl in the midazolam group was significantly more than the propofol group (12.5 mg/hr vs 4 mg/hr) (P = 0.0039). No significant differences were found in MAP (P = 0.51) and HR (P = 0.41) between the groups. The mean extubation time in patients sedated with propofol was shorter than those sedated with midazolam (102 ± 27 min vs 245 ± 42 min, respectively; P < 0.05) but the ICU discharge time was not shorter (47.5 hr vs 36.3 hr, respectively; P = 0.24). CONCLUSIONS: Propofol provided a safe and acceptable sedation for post-CABG surgical patients, significantly reduced the requirement for analgesics, and allowed for more rapid tracheal extubation than midazolam but did not result in earlier ICU discharge.