Acute opioid administration improves work-related exercise performance in patients with chronic back pain.
We studied the impact of acute opioid administration on work-related exercise performance in patients with chronic back pain. A double-blinded, random-order, placebo-controlled, crossover trial was conducted. Subjects were predominantly men (63%), with a mean age of 49 years. Subjects performed a continuous lifting and lowering test to voluntary fatigue at a load equivalent to 33% of their predetermined maximal lifting load twice: Once after receiving a single intravenous dose of 1 mug/kg fentanyl (a narcotic analgesic) and once after saline placebo. Of the 30 subjects undergoing testing, 3 subjects were unable to complete testing due to medication-induced nausea. Subjects lifted on average 29.4 +/- 17.9 kg under the influence of fentanyl versus 25.6 +/- 3.1 kg with placebo (effect size = 0.23). Time to fatigue was higher in the fentanyl group (312 +/- 251.4 vs 231 +/- 199.9 seconds, effect size = 0.40), and these subjects also performed more total work (7004 +/- 5144 vs 4748 +/- 3147 J, effect size = 0.72). Opioid analgesia improves lifting performance in the short term in individuals with chronic back pain. Longer trials of the effectiveness of opioid analgesia as an adjunct to functional restoration programs are recommended.


CONCLUSIONS
This article presents the results of a clinical trial showing that acute opioid administration improves work-related exercise performance in individuals with chronic back pain. Longer trials of the effectiveness of opioid analgesia as an adjunct to functional restoration programs are recommended.
Gross
Douglas P
DP
Department of Physical Therapy, University of Alberta, Edmonton, Canada. dgross@ualberta.ca
Bhambhani
Yagesh
Y
Haykowsky
Mark J
MJ
Rashiq
Saifudin
S
D000328:Adult; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000627:therapeutic use; D001416:Back Pain / Q000188:drug therapy* / Q000503:physiopathology / Q000523:psychology; D002908:Chronic Disease; D018592:Cross-Over Studies; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods; D005260:Female; D005283:Fentanyl / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D007275:Injections, Intravenous; D017770:Lifting; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000379:methods; D017288:Pain Threshold / Q000187:drug effects; D011597:Psychomotor Performance / Q000187:drug effects*; D013647:Task Performance and Analysis; D016896:Treatment Outcome
D000701:Analgesics, Opioid; D005283:Fentanyl