Tympanoplasty under deliberate hypotension by remifentanil

ABSTRACT

Deliberate hypotension is an anesthetic technique that permits the clinician to lower arterial pressure electively in order to provide dry field for the surgeon particularly during microscopic surgery aiming at improving visibility to perform delicate procedures. Using Remifentanil the ultrashort acting synthetic opioid by infusion to induce hypotension was evaluated in this study. Sixty randomized patients undergoing myringoplasty surgery in the Hearing and Speech Institute were randomly allocated into two groups. First group received Remifentanil bolus dose 2 - 3 micro g / kg then infusion 0.5 micro g / kg / minute. Second group received high dose potent inhalational agent in the form of 1- 2 MAC Isoflurane with increments of Propranolol and Fentanyl 1- 2 micro g/ kg under hyperventilation technique guided by end tidal CO2. The two groups were compared as regards to haemodynamic stability, arterial oxygen saturation, facility for intubation, rate of operative field oozing or bleeding, operative time as well as postoperative surgical outcome. The group of patients that received Remifentanil infusion showed lower levels of arterial blood pressure, shorter operative time, better surgical field visualization and better recovery scores when compared with the other group of patients who received potent inhalational agents, increments of beta adrenergic blockers and Fentanyl. There were no significant difference between the two groups concerning facility of endotracheal intubation, mean heart rate values, arterial oxygen saturation as well as postoperative surgical outcome in the form of graft taking and hearing assessment. The use of Remifentanil infusion during myringoplasty surgery to induce hypotension produced lower mean arterial BP values, shorter operative time, better surgical field visualization and better recovery scores whereas it had no significant effect postoperatively on graft taking or hearing assessment