title: Topical glyceryl trinitrate ointment for pain related to anal hypertonia after stapled hemorrhoidopexy: a randomized controlled trial.
abstract: BACKGROUND
  Postoperative pain after stapled hemorrhoidopexy is cause for considerable concern and may be related to contracture of continence muscles.
  
  
  OBJECTIVE
  We compared glyceryl trinitrate 0.4% ointment with lidocaine chlorohydrate 2.5% gel as topical therapy to relieve the pain of anorectal muscular spasm after stapled hemorrhoidopexy.
  
  
  METHODS
  This was a single-blind, parallel-group, randomized controlled trial.
  
  
  METHODS
  The study was conducted at a university teaching hospital in Rome, Italy.
  
  
  METHODS
  Patients with severe postoperative anal pain after stapled hemorrhoidopexy, clinical evidence of anal hypertonia, and elevated anal resting pressure on manometric assessment were enrolled. Patients treated for concomitant anorectal disease were excluded.
  
  
  METHODS
  Participants were randomly assigned to receive twice-daily, local topical application of glyceryl trinitrate or lidocaine for a total of 14 days.
  
  
  METHODS
  Pain intensity was measured on a visual analog scale at baseline and after 2, 7, and 14 days of therapy. Anal resting pressure was measured pre- and postoperatively and after 14 days of therapy.
  
  
  RESULTS
  Of 480 patients undergoing stapled hemorrhoidopexy, 121 had severe postoperative pain (score >3) and underwent clinical examination; 45 patients (13 women, 28 men) had clinically evident anal hypertonia and underwent anorectal manometry; 41 patients had elevated anal resting pressure and entered the study. Mean pain scores were significantly lower with glyceryl trinitrate than with lidocaine on day 2 (2.5 ± 1.0 vs 4.0 ± 1.1, p < 0.0001); day 7 (1.4 vs 2.8, p < 0.0001); and day 14 (0.4 vs 1.4, p = 0.003). Anal resting pressure was significantly lower with glyceryl trinitrate than with lidocaine on day 14 (75.4 ± 7.4 mmHg vs 85.6 ± 7.9 mmHg, p < 0.0001).
  
  
  CONCLUSIONS
  GTN-induced reduction in sphincter tone could not be evaluated during the initial period, when pain was most intense. Because anorectal manometry was performed only in patients with severe pain and clinical evidence of anal hypertonia, firm conclusions cannot be drawn as to frequency of hypertonia after SH. Bias may have been introduced because the surgical team could not be blinded.
  
  
  CONCLUSIONS
  Topical 0.4% glyceryl trinitrate is effective in relieving pain and reducing anal resting pressure in patients with anal hypertonia after stapled hemorrhoidopexy.
authors: Department of Medical and Surgical Sciences and Translational Medicine, St Andrea Hospital, School of Medicine and Psychology, University Sapienza of Rome, Rome, Italy. frasavmari@yahoo.it
authors: Francesco Saverio
authors: FS
authors: Mari
authors: Giuseppe
authors: G
authors: Nigri
authors: Anna
authors: A
authors: Dall'Oglio
authors: Umile Michele
authors: UM
authors: Cosenza
authors: Andrea
authors: A
authors: Milillo
authors: Irene
authors: I
authors: Terrenato
authors: Alessandra
authors: A
authors: Pancaldi
authors: Antonio
authors: A
authors: Brescia
mesh_terms: D000287:Administration, Topical; D000328:Adult; D001003:Anal Canal / Q000187:drug effects / Q000473:pathology*; D005260:Female; D006484:Hemorrhoids / Q000601:surgery*; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009122:Muscle Hypertonia / Q000188:drug therapy* / Q000209:etiology; D005996:Nitroglycerin / Q000008:administration & dosage*; D059408:Pain Management / Q000379:methods*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D017792:Surgical Stapling / Q000009:adverse effects*; D016896:Treatment Outcome
chemical_list: D008012:Lidocaine; D005996:Nitroglycerin