title: Sub-Tenon's anaesthesia versus topical anaesthesia for cataract surgery.
abstract: BACKGROUND
  Local anaesthesia for cataract surgery can be provided by sub-Tenon's or topical anaesthesia. Both techniques offer possible advantages. This review, which originally was published in 2007 and was updated in 2014, was undertaken to compare these two anaesthetic techniques.
  
  
  OBJECTIVE
  Our objectives were to compare the effectiveness of topical anaesthesia (with or without intracameral local anaesthetic) versus sub-Tenon's anaesthesia in providing pain relief during cataract surgery. We reviewed pain during administration of anaesthesia, postoperative pain, surgical satisfaction with operating conditions and patient satisfaction with pain relief provided, and we looked at associated complications.
  
  
  METHODS
  We searched the Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE (last search in November 2014) and the reference lists of published articles. We looked for conferences abstracts and trials in progress and placed no constraints on language or publication status.
  
  
  METHODS
  We included all randomized studies that compared sub-Tenon's anaesthesia versus topical anaesthesia for cataract surgery.
  
  
  METHODS
  We assessed trial quality and extracted data in the format allowing maximal data inclusion.
  
  
  RESULTS
  We included eight studies in this updated review but could retain in the analysis only seven studies on 742 operated eyes of 617 participants. Two cross-over trials included 125 participants, and five parallel trials included 492 participants. These studies were published between 1997 and 2005. The mean age of participants varied from 71.5 years to 83.5 years. The female proportion of participants varied from 54% to 76%. Compared with sub-Tenon's anaesthesia, topical anaesthesia (with or without intracameral injection) for cataract surgery increases intraoperative pain but decreases postoperative pain at 24 hours. The amplitude of the effect (equivalent to 1.1 on a score from 0 to 10 for intraoperative pain, and to 0.2 on the same scale for postoperative pain at 24 hours), although statistically significant, was probably too small to be of clinical relevance. The quality of the evidence was rated as high for intraoperative pain and moderate for pain at 24 hours. We did find differences in pain during administration of local anaesthetic (low level of evidence), and indications that surgeon satisfaction (low level of evidence) and participant satisfaction (moderate level of evidence) were less with topical anaesthesia. There was not enough evidence to say that one technique would result in a higher or lower incidence of intraoperative complications compared with the other.
  
  
  CONCLUSIONS
  Both topical anaesthesia and sub-Tenon's anaesthesia are accepted and safe methods of providing anaesthesia for cataract surgery. An acceptable degree of intraoperative discomfort has to be expected with either of these techniques. Randomized controlled trials on the effects of various strategies to prevent intraoperative pain during cataract surgery could prove useful.
authors: Department of Anesthesiology, Faculty of Medicine, University of Sherbrooke, Sherbrooke, QC, Canada.
authors: Joanne
authors: J
authors: Guay
authors: Karl
authors: K
authors: Sales
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000772:Anesthesia, Local / Q000009:adverse effects / Q000379:methods*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D002387:Cataract Extraction; D005260:Female; D006801:Humans; D008297:Male; D009407:Nerve Block / Q000379:methods*; D010146:Pain / Q000209:etiology; D010147:Pain Measurement; D016032:Randomized Controlled Trials as Topic
chemical_list: D000779:Anesthetics, Local