Effect of General Anesthesia on Intra-ocular Pressure during Ophthalmic Procedures in Our Population

Abstract

Aim: To determine changes in intraocular pressures (IOP) associated with drugs used for general anesthesia (GA) induction in eye surgery. Study design: Observational prospective study Place and duration of study: Department of Ophthalmology, CMH Rawalpindi from 1st March 2015 to 31st May 2016. Methodology: Eighty subjects that were advised to undergone various ophthalmic surgical procedures under GA were included in the study. Visual acuity, intraocular pressure (IOP), extra ocular motility, anterior and dilated posterior segment examination were carried out to determine the ophthalmic status. Mixed anesthetics were used in all patients. IOP was recorded at T1 (10 min before induction of anesthesia), T2 (10 min after intubation), and T3 (at the conclusion of surgery before extudation) using Perkins tonometers. Changes in IOP before induction of GA, after intubation, and just before extubation were recorded. Results: Mean pre-anesthesia IOP for patients of age was 42.3 years with a range of 9-70 years and mean IOP was 16.4 with a range of 10-23 mmHg. There was a significant decrease in the mean IOP at T2 (Perkins: 4-6 mmHg) and T3 (Perkins: 5-8mmHg) as compared to the IOP at T1 (10-18mmHg. The decreases in IOPs at T2 and T3 were similar in both anesthetic groups (T2: P=4-6mmHg; T3: P = 5-8 mmHg). Conclusion: Significant decrease in IOP after GA was observed with mixed anesthetic agents. For management decisions this aspect of general anaesthesia drugs on IOP as noted with currently used anesthetic agents has to be accounted for and decisions are taken accordingly. Keywords: General anesthesia, inhalation anesthetics, intraocular pressure, Perkins tonometers