Comparison of intubating conditions and haemodynamic effects of rocuronium with vecuronium in patients with poor left ventricular ejection fraction undergoing coronary artery bypass graft surgery.
To compare the haemodynamic effects and intubating conditions of rocuronium and vecuronium, 20 patients of either sex with poor left ventricular function (ejection fraction <35%) scheduled for coronary artery bypass surgery were randomly divided into two equal groups. All patients were premedicated with lorazepam and morphine and induced with morphine, midazolam, thiopentone and either vecuronium (0.1 mg/kg) or rocuronium (0.6 mg/kg) as muscle relaxant. All patients were intubated after 3 minutes in the vecuronium group and 90 seconds in the rocuronium group by the same anaesthesiologist. Monitoring in all cases included neuromuscular (train of four- TOF), systemic and pulmonary arterial pressures, cardiac output and calculated haemodynamic variables. Demographic (age, sex and mean ejection fraction) and haemodynamic variables were comparable in both the groups. A significant suppression of the TOF in the vecuronium group was observed despite better intubating conditions in the rocuronium group. The heart rate at 3 minutes and mean arterial pressure at 1 minute was higher in the vecuronium group as compared to the rocuronium group. There were no other significant haemodynamic differences in both the groups. We conclude that rocuronium does provide better intubating conditions at 90 seconds than vecuronium at 3 minutes with no significant differences in the haemodynamic parameters between the two; however, the train of four response does not correlate with intubating conditions.
Swaminathan
M
M
Department of Cardiac Anaesthesia, Escorts Heart Institute and Research Centre, Okhla Road, New Delhi, India. yatinmehta@hotmail.com.
Mehta
Y
Y
Girotra
S
S
Trehan
N
N