The effect of IVPCA morphine on post-hysterectomy bowel function.
BACKGROUND
Although morphine has been shown to induce bowel dysfunction in a dose-dependent fashion, in most relevant studies it was investigated in single bolus injection. Recently, intravenous morphine via patient-controlled analgesia (IVPCA) has been widely used to provide analgesia by divided bolus doses on patients' demand with satisfactory effects. This approach, by reducing the peak serum surge, largely resembles the pharmacokinetic and pharmacodynamic advantage of continuous infusion. There is yet no report on the investigation of its effect on post-operative bowel dysfunction.


METHODS
Fifty-one women who underwent abdominal total hysterectomy (ATH) due to uterine myoma were enrolled to investigate the association between the doses of morphine consumption by PCA and the time of first passage of flatus. In all patients morphine was administered intravenously via a PCA pump immediately after recovery from general anesthesia.


RESULTS
We found that 49 out of 51 patients (96%) exhibited mild pain with IVPCA morphine. They had consumed an average dose of 16.9 mg morphine (range, 0-46 mg) upon the first passage of flatus which occurred 2036.4 min (average) post-operatively. There was no correlation between the dose of morphine and the time of first passage of flatus (r = 0.053, P > 0.05).


CONCLUSIONS
The absence of suppression of bowel movement by IVPCA morphine for post-operative pain control suggests that favorable pharmacokinetic profile of IVPCA can help reduce the morphine-induced bowel dysfunction at its therapeutic level.
Chan
Kuang-Cheng
KC
Department of Anesthesiology, National Taiwan University, College of Medicine and Hospital, Taipei, Taiwan, R.O.C.
Cheng
Ya-Jung
YJ
Huang
Guang-Ta
GT
Wen
Yuan-Jui
YJ
Lin
Chen-Jung
CJ
Chen
Li-Kuei
LK
Sun
Wei-Zen
WZ
D000328:Adult; D000368:Aged; D016058:Analgesia, Patient-Controlled; D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000627:therapeutic use; D005260:Female; D005414:Flatulence; D005769:Gastrointestinal Motility / Q000187:drug effects*; D006801:Humans; D007044:Hysterectomy / Q000009:adverse effects*; D007422:Intestines / Q000502:physiology*; D007889:Leiomyoma / Q000601:surgery; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage* / Q000627:therapeutic use; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy* / Q000209:etiology; D014594:Uterine Neoplasms / Q000601:surgery
D000701:Analgesics, Opioid; D009020:Morphine