Remifentanil versus dexmedetomidine for controlled hypotensive anaesthesia in middle ear surgery

الملخص EN

Objective: Sufficent controlled hypotension is essential to control bleeding in order to improve 'dryness' of the surgical field during middle ear surgery.Remifentanil is a potent short acting synthetic opioid agonist.

Dexmedetomidine is a selective short-acting central α2-adrenergic agonist.This study was carried out to compare between remifentanil and dexmedetomidine, to evaluate their effectiveness to obtain hypotensive technique and controlling intra operative bleeding to obtain 'dry' operative field exposure during middle ear surgery.

Methods: This study included 60 patients planned for middle earsurgery under general anaesthesia.

Patients were divided randomly into two groups (n=30) as Group R (remifentanil infusion0.25-0.50µg/kg/min.) and Group D (dexmedetomidine infusion 0.50µg/kg/hr.).

Mean arterial blood pressure and heart rate were recorded upon arrival in the operating room, 1 minute after onset of the surgery, then every 20 minutes after onset of the surgery, 10 minutes after end of the infusion, and 15 minutes after extubation.

Qualities of the surgical field were rated every10 minutes using a four-point scale.

Results: Demographic data, duration of anaesthesia and duration of hypotension did not differ among the two groups, (P<0.001).

Heart rate and mean arterial pressure were significantly reduced at all time measurements in contrast with the 1st time measurement (t0) in both groups.

Heart rate and mean arterial pressure were significantly lower in Group R compared with Group D at all times after onset the surgery t1-t6, (P<0.05).

The intra-operative bleeding score was significantly lower in Group R than in Group D (P<0.05).

Conclusion: Both remifentanil and dexmedetomidine have induced hypotension intra operatively in patients undergoing middle ear surgery.

Remifentanil is more effective in achieving hypotension and better operative field than dexmedetomidine during middle ear surgery