title: Acetaminophen decreases early post-thoracotomy ipsilateral shoulder pain in patients with thoracic epidural analgesia: a double-blind placebo-controlled study.
abstract: OBJECTIVE
  Despite effective epidural analgesia, up to 85% of post-thoracotomy patients complain of moderate-to-severe ipsilateral shoulder pain. This study assessed the efficacy of acetaminophen in decreasing postoperative shoulder pain after a thoracotomy.
  
  
  METHODS
  Double-blind randomized and placebo-controlled study.
  
  
  METHODS
  University medical center.
  
  
  METHODS
  65 patients.
  
  
  METHODS
  Patients were randomized into 2 groups; 31 patients received acetaminophen (group A), and 34 patients received a placebo (group P). After induction of anesthesia, patients received either a loading dose of acetaminophen, 1000 mg intrarectally, or a placebo suppository. Thereafter, acetaminophen, 650 mg, or a placebo, was administered intrarectally every 4 hours for 48 hours postoperatively.
  
  
  RESULTS
  Postoperative pain at the surgical site and shoulder pain were assessed separately every 4 hours for 48 hours using a numerical rating scale (NRS). Rescue analgesia for severe shoulder pain (NRS > 7) consisted of subcutaneous hydromorphone. Sixty-three patients experienced shoulder pain (97% prevalence). Demographic and intraoperative data were similar between the 2 groups. Average NRS for shoulder pain was higher in group P compared with group A at 8, 12, and 16 hours postoperatively (3.1 +/- 2.9, 2.6 +/- 2.6, 2.3 +/- 2.4 vs 1.8 +/- 2.6, 1.2 +/- 1.5, 1.3 +/- 1.8; P < 0.05). The total dose of hydromorphone did not differ between the 2 groups at 16, 24, and 48 hours.
  
  
  CONCLUSIONS
  Acetaminophen decreases post-thoracotomy ipsilateral shoulder pain when given preemptively and regularly during the first 48 hours postoperatively in patients who received thoracic epidural analgesia.
authors.affiliation: Department of Anesthesiology, CHUM, Hôpital Notre-Dame, 1560 Sherbrooke East, Montreal, Quebec H2L 4M1, Canada.
authors.forename: Thien Bich
authors.initials: TB
authors.lastname: Mac
authors.forename: François
authors.initials: F
authors.lastname: Girard
authors.forename: Philippe
authors.initials: P
authors.lastname: Chouinard
authors.forename: Daniel
authors.initials: D
authors.lastname: Boudreault
authors.forename: Edwin R
authors.initials: ER
authors.lastname: Lafontaine
authors.forename: Monique
authors.initials: M
authors.lastname: Ruel
authors.forename: Pasquale
authors.initials: P
authors.lastname: Ferraro
mesh_terms: D000082:Acetaminophen / Q000008:administration & dosage / Q000627:therapeutic use*; D000285:Administration, Rectal; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015360:Analgesia, Epidural; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy* / Q000209:etiology; D020069:Shoulder Pain / Q000188:drug therapy* / Q000209:etiology; D013488:Suppositories; D013904:Thoracic Vertebrae; D013908:Thoracotomy / Q000009:adverse effects*; D013997:Time Factors
chemical_list: D018712:Analgesics, Non-Narcotic; D013488:Suppositories; D000082:Acetaminophen