Differential analgesic effect of tenoxicam on the wound pain and uterine cramping pain after cesarean section.
BACKGROUND
Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used to enhance opioid analgesia in the acute pain service. The question, however, of whether NSAIDs produce a similar extent of potentiation among different types of pain, has not been thoroughly investigated.


METHODS
A randomized, placebo-controlled, double-blind study was performed to characterize the analgesic effect of tenoxicam, a long-acting NSAID, on resting wound pain, evoked wound pain, and uterine cramping pain after cesarean section. Saline (n = 48) or 20 mg tenoxicam (n = 45) was intravenously injected immediately after clamping the umbilical cord. All patients were instructed to obtain maximal postoperative analgesia by intravenous patient-controlled morphine. RESULTS Tenoxicam profoundly reduced the intensity of uterine cramping pain (3.6 [2.0-5.6] versus 5.5 [3.4-6.6]; p < 0.01) but had no additional effect on wound pain at rest, with movement, changing position, sitting, and walking. Intraoperative injection of 20 mg tenoxicam decreased the demand ratio for patient-controlled analgesia (PCA) and 24-hour morphine consumption by approximately 30%.


CONCLUSIONS
The data show that tenoxicam potentiates opioid analgesic effect on the somatic and visceral types of pain to different extents, and they suggest that intraoperative injection of 20 mg tenoxicam is sufficient to enhance intravenous PCA morphine on uterine cramping pain for the first 24 hours after cesarean section.
Hsu
Hsing-Wen
HW
Department of Anesthesiology, National Taiwan University Hospital, College of Medicine, Taipei, Taiwan.
Cheng
Ya-Jung
YJ
Chen
Li-Kuei
LK
Wang
Yong-Ping
YP
Lin
Chen-Jung
CJ
Lee
Chien-Nan
CN
Sun
Wei-Zen
WZ
D000293:Adolescent; D000328:Adult; D016058:Analgesia, Patient-Controlled; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000627:therapeutic use; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000627:therapeutic use*; D002585:Cesarean Section / Q000009:adverse effects*; D004311:Double-Blind Method; D004357:Drug Synergism; D005260:Female; D006801:Humans; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000627:therapeutic use; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D010894:Piroxicam / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D011247:Pregnancy; D014590:Uterine Contraction / Q000187:drug effects*
D000701:Analgesics, Opioid; D000894:Anti-Inflammatory Agents, Non-Steroidal; D010894:Piroxicam; D009020:Morphine; C032801:tenoxicam