Lidocaine use in cataract surgery

Theme: Cataract surgery*
What: Cataract surgery
Part of: Cataract II: Anterior segment surgery for the cataract surgeon / Cataracte II - Chirurgie du segment antérieur pour le chirurgien spécialiste de la cataracte
When: 6/1/2024, 04:15 PM - 05:45 PM
Where: Room | Salle 801

Abstract

Purpose

There are several methods to achieve anesthesia during cataract surgery. Two of the routinely used methods at the University of Alberta include topical anesthesia (TA) with or without intracameral (IC) anesthesia. While intended to offer additional pain control during surgery, IC anesthesia with lidocaine may cause discomfort during injection and possibly decrease post-operative visual acuity (VA) due to corneal edema. 

Study design

This was a prospective single blinded randomized controlled study. Patients were randomized to receive either intracameral lidocaine (ICL; the study group) or balanced salt solution (BSS; control group). Patients were not aware which group they were assigned to. Patients unable to speak English and those who required IV sedation were excluded from the study due to the need to communicate with the surgeon during the operation. Statistical analysis was done using SAS.

Methods 

Prior to surgery, all patients received lidocaine jelly and tetracaine drops. Patients were offered optional oral lorazepam. The surgeon asked patient at the time of ICL or BSS injection whether they have any pain. Those who experienced pain were asked to rank it on a scale from 0 to 10; 0 being no pain and 10 being the worst pain they ever experienced. At the end of the surgery, the same question was asked about the overall pain experienced during the surgery. Eyes were assessed at same-day post operative visit. 

Results 

106 eyes from 82 patients were included. 53 eyes were in the ICL group and 53 in the control group. The overall pain score was lower (p=0.004) in the ICL group (0.43/10) than in the control group (1.25/10).  There was no difference in the pain experienced during injection of lidocaine or BSS between groups (p=0.270); the average pain on injection overall was 0.54/10. 

Pain scores were higher (p=0.002) in more myopic eyes (IOL power <16.5D, (1.80/10)) than less myopic eyes (0.50/10). A controlled analysis, which included variables that could affect pain scores (higher lorazepam dose, IC phenylephrine), and variables where comparison analyses yielded a p<0.1 (ie sex, myopia), revealed that ICL is an independent predictor of lower pain scores (p=0.018).There was no difference in same-day post-operative logMAR visual acuity (p=0.837) or degree of corneal edema (p=0.900) between groups.

Conclusions

ICL decreases pain during cataract surgery compared to BSS, but the effect is small. Scenarios where ICL may be especially helpful include high myopia because IOL power <16.5D was an independent predictor of higher pain scores. Use of ICL did not cause significant pain at the time of injection compared to BSS. Additionally, there were no observed negative postoperative effects in eyes that received ICL. Overall, ICL is an effective method of supplementing TA during cataract surgery, and while the effect is small, less pain is never a bad thing.

Presenter(s)

Presenting Author: Natalia Binczyk

Additional Author(s):

Heather Burnett, University of Alberta

Christopher Rudnisky, University of Alberta

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