Acetaminophen decreases early post-thoracotomy ipsilateral shoulder pain in patients with thoracic epidural analgesia: a double-blind placebo-controlled study.
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.
Mac
Thien Bich
TB
Department of Anesthesiology, CHUM, Hôpital Notre-Dame, 1560 Sherbrooke East, Montreal, Quebec H2L 4M1, Canada.
Girard
François
F
Chouinard
Philippe
P
Boudreault
Daniel
D
Lafontaine
Edwin R
ER
Ruel
Monique
M
Ferraro
Pasquale
P
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
D018712:Analgesics, Non-Narcotic; D013488:Suppositories; D000082:Acetaminophen