Naloxone infusion after prophylactic epidural morphine: effects on incidence of postoperative side-effects and quality of analgesia.
There have been conflicting reports of the value of naloxone infusions to prevent the side-effects associated with epidural morphine. In our study, 29 patients undergoing thoracotomies for pulmonary surgery received epidural morphine (0.1 mg.kg-1) shortly after induction of anaesthesia. One hour after arrival in the Recovery Room, one of four naloxone bolus and infusion sequences was administered: saline bolus followed by saline infusion; 0.4 microgram.kg-1 naloxone bolus followed by 0.4 microgram.kg-1.hr-1 naloxone infusion; 2.0 micrograms.kg-1 naloxone bolus followed by 2.0 micrograms.kg-1.hr-1 naloxone infusion; and 4.0 micrograms.kg-1 naloxone bolus followed by 4.0 micrograms.kg-1.hr-1 naloxone infusion. Although with the number of patients studied, there were no statistically significant differences among groups, clinically, there was a trend toward decreased analgesia with all three naloxone infusion doses as determined by analgesic requirements, longest analgesic-free period and visual analogue pain scores. In addition, side-effects occurred in all groups. We conclude that prophylactic naloxone, used in this manner, is not an appropriate technique for the prevention of side-effects associated with epidural morphine used for the prevention of pain after thoracotomy.
Gowan
J D
JD
Department of Anaesthesia, Ottawa Civic Hospital, Ontario.
Hurtig
J B
JB
Fraser
R A
RA
Torbicki
E
E
Kitts
J
J
D000368:Aged; D000698:Analgesia; D000767:Anesthesia, Epidural / Q000009:adverse effects; D001784:Blood Gas Analysis; D002986:Clinical Trials as Topic; D003975:Diazepam; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007530:Isoflurane; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000009:adverse effects / Q000037:antagonists & inhibitors; D009270:Naloxone / Q000009:adverse effects / Q000627:therapeutic use*; D009609:Nitrous Oxide; D011183:Postoperative Complications / Q000517:prevention & control*; D011229:Preanesthetic Medication; D011897:Random Allocation; D012129:Respiratory Function Tests
D009270:Naloxone; D009020:Morphine; D007530:Isoflurane; D009609:Nitrous Oxide; D003975:Diazepam