Abstracts of Posters Presented at the International Anesthesia Research Society; 72nd Clinical and Scientific Congress; Orlando, FL; March 7-11, 1998: Ambulatory Anesthesia
Quantitated strabismus surgeries in adult patient become increasing popular and may reduce the re-operation rate . The conventional anesthetic techniques for the strabismus surgery are to administer a retrobuiber block by local anesthetic or general anesthesia with muscle relaxants. With these techniques the quantitative adjustments of extra-ocular muscles during surgery were practically difficult due to paresis of ocular muscles. To perform the intra-operative adjustment of sutures ("awake test"), propofol-fentanyl sedation with topical anesthetic would be an attractive method with respect to the surgical procedure and patient comfort.
Methods: After institutional approval, informed consent was obtained. We studied 7 consecutive patients, 17 to 25 years old, who underwent strabismus surgery using the anesthetic technique described below. ECG, SpO2 and ETCO2 were monitored with 4L/min. of O2 via face mask. These patient were sedated preoperatively with intravenous fentanyl citrate (100 to 150 [micro sign]g) and infusion of intravenous propofol (loading dose of 0.5 to 1.0 mg/kg, followed by a continuous infusion of 2 to 4 mg/kg/hr). Additional bolus of fentanyl (50 to 100 [micro sign]g) to maintain adequate sedation was given. A drop of lidocane 2% was instilled only before the incision of conjunctive. A few minutes prior to the intra-operative adjustment of sutures ("awake test"), propofol infusion was halted. The patient were awakened and asked to fixate the far and near target. Then propofol infusion was restarted to make the patient asleep and suture were adjusted when necessary. At the completion of surgery and 6 hours after the surgery, the patient discomfort was graded by the patient and physician, and the incidence of the intra-operative awareness and postoperative nausea/vomiting was examined.
Results: No patient experienced "severe discomfort" as graded. Only one patient claimed "mild discomfort". One patient experienced the intra-operative awareness except "awake test" for the adjustment of sutures. No patient had nausea/vomiting on the day of surgery. The evaluation of this anesthetic procedure by surgeons were excellent.
Conclusions: Propofol-fentanyl sedation technique can provide the opportunity for intra-operative quantitative adjustments of ocular muscles ("awake test") in adult strabismus surgery without major side effects.
1. Ophthalmology 1995;102:122