
Meta-analysis of 25 RCTs finds perioperative ketamine and esketamine reduce postoperative delirium risk but increase dizziness
AI-summarized from the linked source. Educational brief, not medical advice.
Brief summary
A meta-analysis of 25 randomized controlled trials with 3,344 surgical patients found perioperative ketamine and esketamine were associated with reduced postoperative delirium between days 2 and 7, but significantly increased postoperative dizziness.
What NurseJet pulled from the source
Postoperative delirium (POD) is a common, distressing complication in older surgical patients, yet effective pharmacologic prevention options remain limited. This systematic review and meta-analysis of 25 randomized controlled trials (RCTs) involving 3,344 patients evaluated perioperative administration of ketamine (9 trials) and esketamine (16 trials) compared to placebo or standard care. Both agents were associated with reduced POD incidence (ketamine: risk ratio [RR] 0.69; 95% CI, 0.49–0.98; P = .04; esketamine: RR 0.58; 95% CI, 0.36–0.95; P = .03). Risk reductions were most evident with higher-dose regimens (single bolus: ketamine >0.5 mg/kg or esketamine >0.25 mg/kg; cumulative dose: ketamine >1.0 mg/kg or esketamine >0.5 mg/kg), bolus-plus-infusion administration, and in major surgical procedures. However, the preventative association was present only when delirium was assessed between postoperative days 2 and 7, not within the first 24 hours. Furthermore, ketamine/esketamine significantly increased the risk of postoperative dizziness (RR 1.45; 95% CI, 1.14–1.84; P = .002). Trial sequential analysis indicated that total evidence remains inconclusive due to insufficient overall sample size.
Why this matters for nurses
Surgical and post-anesthesia nurses monitor older adults recovering from general anesthesia for confusion, agitation, and fall risk. While ketamine and esketamine show potential neurocognitive protective signals beyond day 1, their heightened dizziness profile increases post-op balance instability, requiring cautious bedside mobility precautions rather than unreserved clinical adoption.
Bedside takeaway
In a meta-analysis of 25 RCTs (3,344 patients), perioperative ketamine (RR 0.69) and esketamine (RR 0.58) reduced delirium at days 2–7 but significantly increased dizziness (RR 1.45).
Key takeaways
- Meta-analysis analyzed 25 RCTs with 3,344 patients receiving perioperative ketamine (9 trials) or esketamine (16 trials).
- Both agents were associated with lower POD incidence versus control: ketamine RR 0.69 (P = .04) and esketamine RR 0.58 (P = .03).
- Delirium reduction was apparent at postoperative days 2 to 7, but not during the initial 24 hours.
- Dizziness risk was significantly elevated in treated patients (RR 1.45; 95% CI, 1.14–1.84; P = .002), and trial sequential analysis found cumulative sample size insufficient to draw definitive conclusions.
Practice implications
- Screen surgical patients systematically for emergence and delayed delirium using validated tools (such as CAM or CAM-ICU) through postoperative day 7, implement strict fall and dizziness precautions when ketamine derivatives are administered, and avoid assuming early alertness guarantees absence of delayed delirium.
Limitations & cautions
- Trial sequential analysis confirmed current evidence remains inconclusive due to inadequate total information size; dizziness was increased (RR 1.45); high heterogeneity in surgical populations and anesthesia protocols.
- AI-summarized from the linked source. Review the original article before applying to practice.
Citations
Exact source links
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Anesthesia and analgesia (PubMed)
Anesthesia and analgesia (PubMed). Effects of Ketamine and Esketamine on Postoperative Delirium After General Anesthesia: A Meta-Analysis and Meta-Regression Analysis.
https://pubmed.ncbi.nlm.nih.gov/42887017/
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