title: Meta-analysis of the use of glyceryl trinitrate ointment after haemorrhoidectomy as an analgesic and in promoting wound healing.
abstract: BACKGROUND
  Glyceryl Trinitrate (GTN) ointment has been used to treat anal fissure and pain relief in haemorrhoids, but the value of its use post-haemorrhoidectomy as an analgesic and in wound healing is unclear. The side effect of headache has often been an associated problem. Therefore, a meta-analysis of randomised controlled trials was carried out investigating the role of GTN post-haemorrhoidectomy as an analgesic, its role in would healing and the unwanted incidence of headache.
  
  
  METHODS
  A structured literature search from 1966 to 2009, both paper and online, with no language barrier was carried out. 760 papers were identified and 5 randomised control trials which met the entry criteria were included in this study.
  
  
  RESULTS
  A total of 333 patients were included in the meta-analysis. The results revealed that GTN ointment was statistically significant in reducing pain on Day 3 and 7 compared to the placebo group. Day 3 shows a pain score of - 1.51 (p value of 0.029) and Day 7 by - 1.66 (p value of 0.014) respectively. However, it was not significant in reducing pain on Day 1. The Odds ratio for wound healing after GTN treatment at 3 weeks was 3.57 (P < 0.0001) when compared to the placebo group. Side effect of headache was not statistically significant.
  
  
  CONCLUSIONS
  This meta-analysis has shown that GTN ointment used post-haemorrhoidectomy has a significant analgesic effect in the intermediate time period (ie. Days 3-7). It also significantly improved wound healing at 3 weeks.
authors.affiliation: North Tees University Hospital, Hardwick Lane, Stockton on Tees, TS19 8, UK. Kumaran95@hotmail.com
authors.forename: K
authors.initials: K
authors.lastname: Ratnasingham
authors.forename: M
authors.initials: M
authors.lastname: Uzzaman
authors.forename: S M
authors.initials: SM
authors.lastname: Andreani
authors.forename: D
authors.initials: D
authors.lastname: Light
authors.forename: B
authors.initials: B
authors.lastname: Patel
mesh_terms: D000700:Analgesics / Q000627:therapeutic use*; D006261:Headache / Q000453:epidemiology; D006484:Hemorrhoids / Q000601:surgery*; D006801:Humans; D005996:Nitroglycerin / Q000627:therapeutic use*; D009824:Ointments; D010147:Pain Measurement; D010149:Postoperative Pain / Q000517:prevention & control*; D014945:Wound Healing
chemical_list: D000700:Analgesics; D009824:Ointments; D005996:Nitroglycerin