Efficacy of subtenon block in infants - a comparison with intravenous fentanyl for perioperative analgesia in infantile cataract surgery

BackgroundGeneral anesthesia with opioids provides good perioperative analgesia in infantile ocular surgeries but is associated with the risk of respiratory depression and postoperative emesis. This study aimed to assess the effectiveness of subtenon block for providing perioperative analgesia in infants undergoing cataract surgeries. MethodsIn this prospective, randomized, controlled, double-blinded trial, 63 infants of ASA grade I and II (1-12months) were recruited to receive either subtenon block (Group SB) or 1gkg(-1) i.v. fentanyl (Group F) after induction of anesthesia. Primary outcome was the number of infants requiring rescue analgesia during 4-h study period before discharge of the infants. Secondary outcomes assessed were CRIES pain score, incidence of oculocardiac reflex, surgical difficulty, and incidence of postoperative emesis. ResultsThe number of infants requiring rescue analgesia during 4-h study period was significantly less in Group SB (n=6/32, 18.8%) compared to Group F (n=14/31, 45.2%, P=0.032). CRIES scores were significantly lower at and after 40min compared to immediate postoperative period in Group F while these were comparable at all time intervals in Group SB. CRIES scores were significantly lower in Group SB compared to Group F at all time intervals except at 1h. The incidence of oculocardiac reflex and the postoperative emesis were comparable in both the groups. ConclusionSubtenon block is an effective superior technique for postoperative analgesia compared to intravenous fentanyl in infants undergoing cataract surgery.