Abstract
Purpose :
The purpose of this study is to assess the impact of neurolept anesthesia administration timing on the perception of pain in patients undergoing refractive laser-assisted cataract surgery (ReLACS).
Methods :
This is a prospective REB randomized control trial at an ambulatory surgical center in Toronto, Ontario, Canada. Patients undergoing cataract surgery were selected in a consecutive manner. Patients were randomized to either receiving neurolept anesthesia following completion of the ReLACS procedure and just prior to draping the eye (standard, n = 38), or, prior to the initiation of the ReLACS procedure (early, n = 35). Primary outcome metrics included pain scores on the visual analogue scale (VAS) from zero (no pain) to ten (unbearable pain) at post-operative day zero (POD0) and post-operative week one (POW1). Secondary outcome measures included a State-Trait Anxiety Inventory (STAI) pre-operative anxiety questionnaire (measured on a scale of 20-80), surgeon and anesthesiologist patient cooperation scores measured on a scale of zero (no event) to three (marked eye and head movement and lid squeezing), ocular metrics (anterior chamber depth, intraocular pressure, surgical time, phacoemulsification energy), and perioperative vitals.
Results :
Mean pain scores of early and standard groups at POD0 were 0.59 and 0.79 (p = 0.38), respectively, and at POW1 were 0.76 and 0.87 (p = 0.71), respectively. Linear regression analysis of pain scores incorporating all independent variables (ocular metrics and perioperative vitals) between both groups were also not statistically significant at POD0 (p = 0.40) and POW1 (p = 0.17). In all patients, each 1 mm increase of anterior chamber depth caused an increase of 1.23 pain units (p = 0.02) at POW1. For pain scores at POW1 in all patients, the second eye had an increase of 0.70 pain units (p = 0.02) relative to the first eye.
Conclusions :
In patients undergoing refractive laser assisted cataract surgery, there was no difference in pain scores between early and standard timing of neurolept anesthesia administration at both POD0 and POW1. Patients perceived increased levels of pain in the second eye at POW1 relative to their first eye. Furthermore, an increase in ACD was also strongly correlated with an increase in pain scores at POW1.
This is a 2021 ARVO Annual Meeting abstract.