Effects of a small-dose remifentanil on the cardiovascular responses associated with tracheal extubation after surgery

Aim To observe the effect of a small-dose remifentanil during extubation on cardiovascular responses associated with tracheal extubation following thoracic surgery.Methods 60 ASA physical status 1 or 2 patients,scheduled for elective thoracic surgery were randomly allocated to remifentanil group(group R) or control group(group C) with 30 cases each.Anesthesia was induced with Midazolam(0.08～0.1 mg·kg~(-1)),Fentanyl(2 μg·kg~(-1)),Propofol(1.5 mg·kg~(-1)) and Rocuronium(0.8 mg·kg~(-1)) and was maintained with inhalation of Isoflurane and a continuous infusion of Remifentanil 0.05～0.2 μg·kg~(-1)·min~(-1).At the end of surgery,a small-dose remifentanil was infused in group R or saline in group C and tracheal extubation was performed when standard criteria were achieved.SBP,DBP and HR were recorded respectively at pre-operation、1min pre-extubation,at extubation and 1,3,5 min after extubation.Results There were no statistical differences between the two groups with respect to sex、weight、age、duration of surgery and anesthesia,type of operation,or with respect to pre-operation blood pressure,heart rate(P0.05).After extubation,the cardiovascular reactions were stable in group R.Comparing with R group,SBP,DBP,HR and RPP in group C significantly increased at extubation 、1 min pre-extubation and 1 min after extubation.Conclusion The hypertension and tachycardia occurring during tracheal extubation can be attenuated by a small-dosage remifentanil.