RESUMO
OBJECTIVES: To determine the degree of intraocular pressure (IOP) rise following retrobulbar anaesthetic injection as well as the optimal time required for the return of the IOP to the pre-injection level following ocular massage. MATERIALS AND METHODS: Using the Perkins hand-held tonometer, the IOP of consecutive adult patients were measured in the operating room before local anaesthetic (3 ml of 2% xylocaine with or without adrenaline) injection; immediately after injection and every minute following ocular massage for the next 5 minutes. RESULTS: Twenty-three eyes of 17 patients, aged 23-71 years, were studied. The mean (+/- SD) baseline (preinjection) IOP was 16.6 (+/- 6.8) mmHg. Immediately after the injection the IOP rose by 11.8-80% with a mean of 37.3 +/- 16.8% (95% CI: 30.4-44.2). By 3 minutes the IOP had returned to the pre-injection level. After 3 minutes the IOP had become lower than the pre-injection level (p < 0.05) CONCLUSIONS: IOP rise following retrobulbar injection of 3 ml of local anesthetic varies from 11.8-80%. Digital ocular massage lowers the IOP to pre-injection level in 60.2% in 3 minutes; in 5 minutes it lowers the IOP to preinjection level in all eyes and to below pre-injection level 86%.
