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A Journal on Anesthesiology, Resuscitation, Analgesia and Intensive Care

Official Journal of the Italian Society of Anesthesiology, Analgesia, Resuscitation and Intensive Care
Indexed/Abstracted in: Current Contents/Clinical Medicine, EMBASE, PubMed/MEDLINE, Science Citation Index Expanded (SciSearch), Scopus
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Minerva Anestesiologica 2017 Nov 17

DOI: 10.23736/S0375-9393.17.12271-6


language: English

Heterogenic control groups in randomized, controlled, analgesic trials of total hip- and knee arthroplasty

Anders P. KARLSEN 1, 2 , Ole MATHIESEN 1, Jørgen B. DAHL 2

1 Department of Anaesthesia, Zealand University Hospital, Koege, Denmark; 2 Department of Anaesthesia, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark


BACKGROUND: Postoperative analgesic interventions are often tested adjunct to basic non- opioid analgesics in randomized controlled trials (RCTs). Consequently, treatment in control groups, and assay sensitivity, differs between trials. We hypothesized that postoperative opioid requirements and pain intensities varies between different control groups in analgesic trials. METHODS: Control groups from RCTs investigating analgesic interventions after total hip and knee arthroplasty were categorized based on standardized basic analgesic treatment. Morphine consumption 0-24h postoperatively, and resting pain scores at 6 and 24 hours for subgroups of basic treatments, were compared with ANOVA. In an additional analysis, we compared pain and opioid requirements in trials where NSAID was administered as an intervention with trial where NSAID was administered in a control group.
RESULTS: We included 171 RCTs employing 28 different control groups with large variability in pain scores and opioid requirements. Four types of control groups (comprising 78 trials) were eligi- ble for subgroup comparisons. These subgroups received: ‘opioid’, ‘NSAID+opioid’, ‘acetamino- phen+opioid’, or ‘NSAID+acetaminophen+opioid’. Morphine consumption and pain scores varied substantially between these groups, with no consistent superior efficacy in any subgroup. Addi- tionally, trials administering NSAID as an intervention demonstrated lower pain scores and opioid requirements than trials where NSAID was administered in a control group.
CONCLUSIONS: Analgesic treatment in RCT control groups varies considerably. Control groups receiving various combinations of opioid, NSAID and acetaminophen did not differ consistently in pain and opioid requirements. Pain and opioid requirements were lower in trials administering NSAID as an intervention compared with trials administering NSAID in a control group.

KEY WORDS: Pain, postoperative - Total hip replacement - Total knee replacement - Anti-inflammatory agents, non-steroidal - Acetaminophen - Opioids

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Publication History

Article first published online: November 17, 2017
Manuscript accepted: November 14, 2017
Manuscript revised: October 16, 2017
Manuscript received: June 30, 2017

Cite this article as

Karlsen AP, Mathiesen O, Dahl JB. Heterogenic control groups in randomized, controlled, analgesic trials of total hip- and knee arthroplasty. Minerva Anestesiol 2017 Nov 17. DOI: 10.23736/S0375-9393.17.12271-6

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