Delirium Risk After Surgery, and What to Do About It

An unusual kind of meta-analysis gives us some answers we can use

What’s the Claim?

A meta-analysis that used individual patient data (very unusual!) from 21 studies of patients undergoing noncardiac surgery identified a number of factors associated with an increased risk of postoperative delirium. Those most useful to surgeons performing hip or knee arthroplasty were:

  • American Society of Anesthesiologists (ASA) status 4 (odds ratio [OR], 2.4 [95% CI 1.4 to 4.1])
  • Older age (OR for 65 to 85 years, 2.7 [2.2 to 3.3]; OR for > 85 years, 6.2 [4.7 to 8.4])
  • Low body mass index (OR for body mass index < 18.5, 2.3 [1.6 to 3.1])
  • A history of delirium (OR, 3.9 [2.7 to 5.7]) or preoperative cognitive impairment (OR, 4.0 [2.9 to 5.4])

How’s It Stack Up?