The effect of sub-Tenon's bupivacaine on oculocardiac reflex during strabismus surgery and postoperative pain: A randomized clinical trial

Abstract

Purpose:Oculocardiac reflex (OCR), defined as bradycardia induced by manipulation of extraocular muscles, is a serious complication during strabismus surgery for which prevention and proper management is required. In the present study, we investigated the efficacy of sub-Tenon injection of bupivacaine for prevention of OCR and postoperative pain.Methods:A prospective randomized controlled clinical trial was conducted. Fifty patients who were candidates for strabismus surgery were randomized into case (sub-Tenon's bupivacaine injection) or control (normal saline injection) groups. Standard strabismus surgery was performed for all cases. Occurrence and severity of OCR (primary outcome) and postoperative pain (using the Visual Analog Scale) were compared between the two groups.Results:Both incidence (32% vs. 100%; P = 0.002) and severity of OCR (mean heart rate decrease, 10.1 vs. 38.7 beats/minute; P < 0.001) were significantly lower in the study group compared to those in the control group. Postoperative pain scores were significantly lower in the case group than in the control group (mean score, 2.8 vs. 5.9 at 60 minutes after surgery; P < 0.001).Conclusions:Sub-Tenon injection of bupivacaine as a local anesthetic can significantly prevent OCR and decrease the severity of bradycardia. This technique can also diminish postoperative pain in patients who underwent strabismus surgery.

A Comparative Study Between Single Medial Canthus Injection Using 13 x 0.45 mm Needle and Posterior Sub-Tenon Injection as Local Anesthesia Techniques for Strabismus Surgery in Adults

“…The current study revealed that PBA and STA provided the best safety profile with no recorded cases of OCR or postoperative nausea and vomiting. In agreement with this finding, Talebnejad et al [26] concluded that sub-Tenon injection of bupivacaine as a local anesthetic significantly prevented OCR and decreased the severity of bradycardia in pediatric patients who underwent strabismus surgery.…”

Efficacy of Sub-Tenon's Block in Paediatric Strabismus Surgery in Terms of Reduction in Oculocardiac Reflex

“…This study also shows that sub-tenon's injection of bupivacaine is associated with decreased postoperative pain. 16 Varposhti et al compared the effect of Tetracaine topical eye drops with placebo and found the incidence and severity of oculocardiac reflex was more in placebo group during the muscle cutting phase of the surgery but there was no difference between the two during the muscle release stage. 13 In our study we did not sub classify the results in to release and cutting phase.…”

“…15 One of the options is to give sub-tenon's injection of bupivacaine after the induction of general anaesthesia to prevent the occurrence of oculocardiac reflex. 4,16,17 Talebnejad et al reported 32% incidence of oculocardiac reflex in sub-tenon's group versus 100% in control group who received no injection (p=0.002) which is statistically significant reduction. 16 similarly, Bakr et al reported incidence of oculocardiac reflex in 18% of patients versus 38% in those who received placebo (0.9% normal saline) injections (p=0.003) which is statistically significant.…”

“…4,16,17 Talebnejad et al reported 32% incidence of oculocardiac reflex in sub-tenon's group versus 100% in control group who received no injection (p=0.002) which is statistically significant reduction. 16 similarly, Bakr et al reported incidence of oculocardiac reflex in 18% of patients versus 38% in those who received placebo (0.9% normal saline) injections (p=0.003) which is statistically significant. 18 Though no local study is found available online on this topic to the best of our knowledge.…”