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Canadian Journal of Anesthesia/Journal canadien d'anesthésie

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01-10-2011 | Reports of Original Investigations

A systematic review of intravenous ketamine for postoperative analgesia

Authors: Kevin Laskowski, MD, Alena Stirling, MD, William P. McKay, MD, Hyun J. Lim, MD

Published in: Canadian Journal of Anesthesia/Journal canadien d'anesthésie | Issue 10/2011

Abstract

Purpose

Perioperative intravenous ketamine may be a useful addition in pain management regimens. Previous systematic reviews have included all methods of ketamine administration, and heterogeneity between studies has been substantial. This study addresses this issue by narrowing the inclusion criteria, using a random effects model, and performing subgroup analysis to determine the specific types of patients, surgery, and clinical indications which may benefit from perioperative ketamine administration.

Source

We included published studies from 1966 to 2010 which were randomized, double-blinded, and placebo-controlled using intravenous ketamine (bolus or infusion) to decrease postoperative pain. Studies using any form of regional anesthesia were excluded. No limitation was placed on the ketamine dose, patient age, or language of publication.

Principal findings

Ninety-one comparisons in seventy studies involving 4,701 patients met the inclusion criteria (2,652 in ketamine groups and 2,049 in placebo groups). Forty-seven of these studies were appropriate for evaluation in the core meta-analysis, and the remaining 23 studies were used to corroborate the results. A reduction in total opioid consumption and an increase in the time to first analgesic were observed across all studies (P < 0.001). The greatest efficacy was found for thoracic, upper abdominal, and major orthopedic surgical subgroups. Despite using less opioid, 25 out of 32 treatment groups (78%) experienced less pain than the placebo groups at some point postoperatively when ketamine was efficacious. This finding implies an improved quality of pain control in addition to decreased opioid consumption. Hallucinations and nightmares were more common with ketamine but sedation was not. When ketamine was efficacious for pain, postoperative nausea and vomiting was less frequent in the ketamine group. The dose-dependent role of ketamine analgesia could not be determined.

Conclusion

Intravenous ketamine is an effective adjunct for postoperative analgesia. Particular benefit was observed in painful procedures, including upper abdominal, thoracic, and major orthopedic surgeries. The analgesic effect of ketamine was independent of the type of intraoperative opioid administered, timing of ketamine administration, and ketamine dose.

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Title: A systematic review of intravenous ketamine for postoperative analgesia
Authors: Kevin Laskowski, MD
Alena Stirling, MD
William P. McKay, MD
Hyun J. Lim, MD
Publication date: 01-10-2011
Publisher: Springer-Verlag
Published in: Canadian Journal of Anesthesia/Journal canadien d'anesthésie / Issue 10/2011
Print ISSN: 0832-610X
Electronic ISSN: 1496-8975
DOI: https://doi.org/10.1007/s12630-011-9560-0

At a glance: The STEP trials

Springer Medicine

A systematic review of intravenous ketamine for postoperative analgesia

Abstract

Purpose

Source

Principal findings

Conclusion

At a glance: The STEP trials

Springer Medicine

Abstract

Purpose

Source

Principal findings

Conclusion

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