BACKGROUND Induction of anaesthesia with propofol and remifentanil often induces unwanted bradycardia and hypotension, raising concerns regarding tissue oxygenation. The electrophysiological cardiac effects of remifentanil can be reversed by atropine.
OBJECTIVE To investigate if prophylactic administration of atropine can attenuate the negative haemodynamic effects of propofol and a high dose of remifentanil during induction of anaesthesia.
DESIGN A double-blind, randomised controlled trial.
SETTING Single-centre, University Medical Center Groningen, The Netherlands.
PATIENTS Sixty euvolaemic patients scheduled for surgery under general anaesthesia.
INTERVENTIONS Anaesthesia was induced and maintained with a target-controlled infusion of propofol with a target effect-site concentration (C-e) of 2.5 mu g ml(-1), remifentanil (target-controlled infusion), (C-e 8 ng ml(-1)) and cis-atracurium. Methylatropine (500 mu g) or 0.9% saline was administered at immediately before induction of anaesthesia.
MAIN OUTCOME MEASURES The changes (Delta) in mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), rate pressure product, cerebral tissue oxygenation and peripheral tissue oxygenation between induction of anaesthesia (T-0) and 10 min later (T-10).
RESULTS Atropine significantly attenuated the changes in the outcome measures between T0 and T10. Median (inter-quartile range) changes were MAP, Delta = -24 (-40 to -21) vs. Delta = -37 mmHg (-41 to -31) (P = 0.02); HR, Delta = 0 +/- 13 vs. -19 +/- 11 bpm (P
CONCLUSION Administration of atropine, before induction of anaesthesia with propofol and high-dose remifentanil, can significantly reduce the decreases in HR, MAP and CI.