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Postop Delirium and POCD
TEXTIntraop II · 9 min read
Avoid benzos, meperidine, anticholinergics. Bring glasses + hearing aids. Bring family. Multimodal pain. These changes work.
After this lesson you can
2 min read8 sections- Screen for delirium with CAM-ICU.
- Identify modifiable risk factors.
- Prevent delirium intraoperatively.
- Treat acute delirium safely.
Delirium vs POCD
- acute (hours-days)
- fluctuating
- inattention dominant
- often hyperactive (agitation) or hypoactive (lethargy) — both forms exist
Same risk profile (age, baseline cognition).
Postoperative neurocognitive disorder (PND) is umbrella term in newer DSM classification.
Risk factors
Baseline cognitive impairment + dementia.
Sensory impairment (vision, hearing).
Polypharmacy.
ETOH/sedative dependence.
Severity of surgery (cardiac, hip, trauma).
Postop complications.
Sleep disruption.
Intraoperative burst suppression on EEG.
Recovery in unfamiliar environment.
Restraints.
Foley catheter.
Pain + opioids.
Drug triggers — avoid
Meperidine (normeperidine accumulates, neurotoxic — banned in elderly).
Tertiary anticholinergics (atropine, scopolamine, diphenhydramine, oxybutynin).
Tramadol (CNS effects + serotonin).
- midazolam minimal/none
- fentanyl or morphine over meperidine
- glycopyrrolate over atropine
- multimodal opioid-sparing
Non-pharmacologic prevention bundle
Family presence at bedside.
Sleep-wake cycle preservation (no overnight blood draws if avoidable, lights off at night, minimal alarms).
Early mobilization (day 1).
Adequate hydration + nutrition.
Reorientation cues (date board, family photos).
Avoid restraints + Foley if possible.
Treat pain + constipation + urinary retention.
Anesthetic technique
Avoid prolonged burst suppression (BIS <20) in elderly — target 40-60.
Multimodal opioid-sparing analgesia.
Regional anesthesia when feasible (no clear advantage over GA for delirium per REGAIN trial but reduces opioid).
Normothermia.
Avoid offending drugs as above.
Anesthesia handoff includes delirium-risk flagging.
Treatment if delirium occurs
Stop offending drugs.
Pharmacologic only if severe agitation + safety concern: low-dose haloperidol 0.5-1 mg IM/IV (avoid in QT prolongation, Parkinson disease).
Olanzapine 5-10 mg orodispersible if oral access.
AVOID benzodiazepines (worsen delirium except in alcohol/benzo withdrawal).
AVOID anticholinergics.
Dexmedetomidine 0.2-0.7 mcg/kg/hr in ICU setting is the modern alternative — calming without delirium-precipitating effect.
POCD — postoperative cognitive dysfunction
Distinguished from delirium: POCD is a SUBTLE PERSISTENT cognitive change (memory, executive function, processing speed) detected by neuropsychological testing at 1, 3, 6 months post-op — NOT acute confusion.
Incidence in elderly major surgery: ~25% at 1 week, ~10-15% at 3 months.
- neuroinflammation cascade from surgical insult
- anesthetic-mediated effects on tau/amyloid
- perioperative hypotension/hypoxia
- unmasking of preclinical Alzheimer's
ISPOCD trials showed POCD rates similar between regional and GA, suggesting the surgical stress itself (not the anesthetic technique) is the dominant driver.
Counsel patients + families pre-op in major elective surgery so they aren't blindsided by post-op cognitive changes.
EEG-guided depth + intra-op hypotension
ENGAGES trial + others: EEG-guided anesthesia (BIS or processed EEG) reduced burst suppression in elderly cases but DID NOT significantly reduce delirium incidence in larger trials.
- monitor depth where available
- target BIS 40-60 (avoid prolonged <20 which represents burst suppression)
- but don't expect dramatic delirium reduction from this alone
INTRA-OP HYPOTENSION matters more — MAP drops >20% from baseline for sustained periods correlate with postop delirium, AKI, myocardial injury.
Maintain MAP within 10-20% of awake baseline (especially in chronic HTN where autoregulation is right-shifted).
⚠ Common pitfalls
- Treating agitation with benzodiazepines — worsens delirium; haloperidol or dexmedetomidine preferred.
- Missing hypoactive delirium — quiet, withdrawn, but cognitively impaired.
- Routine benzo pre-medication in elderly — reduces compliance but worsens postop delirium.
- Burst-suppression in elderly — associated with worse postop delirium.
💎 Clinical pearls
- CAM-ICU: acute change + fluctuating course + inattention + altered LOC or disorganized thinking.
- Risk factors: age >65, baseline cognitive impairment, sensory deprivation, sleep disruption, dehydration.
- Intraop strategies: avoid burst suppression, minimize sedatives, multimodal opioid-sparing.
- Dexmedetomidine for sedation when needed in delirium — non-benzodiazepine, reversible.
Recap
- CAM-ICU: acute change + fluctuating course + inattention + altered LOC or disorganized thinking.
- Risk factors: age >65, baseline cognitive impairment, sensory deprivation, sleep disruption, dehydration.
- Intraop strategies: avoid burst suppression, minimize sedatives, multimodal opioid-sparing.
- Dexmedetomidine for sedation when needed in delirium — non-benzodiazepine, reversible.
Mark each section done to complete the module.