Abstracts of Posters Presented at the International Anesthesia Research Society; 72nd Clinical and Scientific Congress; Orlando, FL; March 7-11, 1998: Ambulatory Anesthesia
Introduction. Topical anesthesia for cataract surgery is gaining in popularity with ophthalmologists and anesthesiologists.  Topical anesthesia is less invasive than other methods of local anesthesia for cataract extraction including retrobulbar and peribulbar injection and thus, carries far less risk of complications. We undertook a prospective, randomized study to compare the safety and efficacy of topical versus retrobulbar anesthesia for combined phacoemulsification-intraocular lens insertion and trabeculectomy.
Methods. With IRB approval and written consents, 40 patients were prospectively assigned to the topical (Group 1) or retrobulbar (Group 2) groups by permuted block restricted randomization. Patients randomized to the topical group received two drops of bupivacaine hydrochloride 0.75% every five minutes times three, beginning 20 minutes before the procedure. In the operating room, Group 1 patients were given midazolam hydrochloride 0.015 mg/kg intravenously and fentanyl 1 [micro sign]g/kg intravenously and an additional two drops bupivacaine 0.75% were placed in the operative eye. Patients randomized to the retrobulbar group were given methohexital 1% titrated to unconsciousness (approximate dose required 0.5-1 mg/kg). A retrobulbar block was performed with a 23 gauge retrobulbar needle using a solution of lidocaine 2% (2 ml) bupivacaine 0.75% (2 ml) and hyaluronidase 150 units. A visual analog pain scale was used to assess the degree of pain during surgery and postoperatively. Vital signs were recorded pre- and intraoperatively and in the recovery room. The degree to which eye movement, touch, and light caused patient discomfort were assessed. Complications and operative conditions were recorded. Twenty-four hours postoperatively patient satisfaction and supplemental analgesic use were assessed.
Results. Data were analyzed using the Chi-square and T-test. There was no difference in the surgical time, operating conditions (p=0.5), pain during surgery (p=0.35), or surgical outcome. There was more postoperative pain (p<0.01) in the topical group. Chemosis, subconjunctival hemorrhage and eyelid hemorrhage were seen exclusively in the retrobulbar group. Patient satisfaction and vital signs were equivalent in both groups.
Conclusion. Patient satisfaction and operative conditions for combined phacoemulsification -intraocular lens implantation and trabeculectomy were equivalent when comparing topical anesthesia with retrobulbar anesthesia. Anesthetic related complications, although minor, were more common in the retrobulbar anesthesia group. Topical anesthesia is a safe and acceptable alternative for combined surgery.
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