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Postoperative delirium — Clinical Guidelines

Overview

Postoperative delirium (POD) is a common and serious complication following major surgeries, particularly in emergency gastrointestinal surgeries and elderly patients, characterized by acute changes in cognition, attention, and consciousness 1 2 29.

Diagnosis

Key Diagnostic Criteria: Acute onset, fluctuating course, inattention, disorganized thinking, and altered level of consciousness 29.

Recommended Tests: Confusion Assessment Method (CAM) or Intensive Care Delirium Screening Checklist (ICDSC) 4.

Grading: No standardized grading system universally accepted; clinical assessment tools are crucial 4.

Management

First-Line Treatments:

- Non-pharmacological: Early mobilization, minimizing sedation, maintaining light sleep 4 11 17. - Pharmacological: Limited evidence; avoid unnecessary medications, particularly anticholinergics 3 12.

Adjunctive Treatments:

- Anesthetic Depth Control: BIS monitoring to avoid deep anesthesia 10 11 22. - Yokukansan (TJ-54): Potential efficacy in reducing delirium, though further evidence needed 6. - Dexmedetomidine: Reduced incidence of postoperative agitation compared to propofol 26.

Special Populations

Elderly: Higher risk due to polypharmacy and age-related changes; focus on minimizing anticholinergic burden and optimizing anesthetic depth 3 8 29.

Comorbidities: Frailty and preoperative cognitive impairment increase risk; comprehensive geriatric assessment recommended 14 28.

Key Recommendations

Preoperative Identification and Risk Assessment: Identify high-risk patients preoperatively, including those with frailty, cognitive impairment, and polypharmacy (Evidence: Strong 4 8 14).

Minimize Sedation and Opioid Use: Limit intraoperative and postoperative sedation and opioid use to reduce delirium risk (Evidence: Moderate 13 22).

Implement Multimodal Non-Pharmacological Interventions: Early mobilization, family involvement, and minimizing environmental stressors (Evidence: Moderate 4 17).

Monitor Anesthetic Depth: Use BIS monitoring to guide anesthetic depth and avoid deep sedation (Evidence: Moderate 10 11 22).

Consider Non-Traditional Pharmacological Approaches: Evaluate use of agents like dexmedetomidine and Yokukansan for delirium prevention (Evidence: Weak 6 26).

References

1 Lyu W, Wang Z, Yang C, Wang X, Feng H, Jiao Y et al.. Delirium after emergency surgery in patients with gastrointestinal obstruction or perforation: a retrospective cohort study for 5 years. Journal of gastrointestinal surgery : official journal of the Society for Surgery of the Alimentary Tract 2025. link 2 Finne KF, Thorup T, Skovsen APG, Tolstrup MB. Outcomes of a delirium prevention program after major abdominal emergency surgery: An interventional study. World journal of surgery 2025. link 3 Moellmann HL, Boulghoudan S, Kuhlmann J, Rahm L, Frohnhofen H. Polypharmacy and anticholinergic burden as risk factors for postoperative delirium in surgical medicine. Zeitschrift fur Gerontologie und Geriatrie 2025. link 4 Aldecoa C, Bettelli G, Bilotta F, Sanders RD, Aceto P, Audisio R et al.. Update of the European Society of Anaesthesiology and Intensive Care Medicine evidence-based and consensus-based guideline on postoperative delirium in adult patients. European journal of anaesthesiology 2024. link 5 Rosenberg K. Factors Associated with Post-Op Delirium Identified. The American journal of nursing 2024. link 6 Kotake K, Matsunuma S, Takahashi T, Kitamura N, Kawakami Y. Yokukansan (TJ-54) in patients undergoing surgery: A systematic review and meta-analysis. Geriatric nursing (New York, N.Y.) 2023. link 7 Hao D, Fritz BA, Saddawi-Konefka D, Palanca BJA. Pro-Con Debate: Electroencephalography-Guided Anesthesia for Reducing Postoperative Delirium. Anesthesia and analgesia 2023. link 8 Rosenberg K. Risk Factors for Postoperative Delirium Identified. The American journal of nursing 2022. link 9 Pérez-Otal B, Aragón-Benedí C, Pascual-Bellosta A, Ortega-Lucea S, Martínez-Ubieto J, Ramírez-Rodríguez JM. Neuromonitoring depth of anesthesia and its association with postoperative delirium. Scientific reports 2022. link 10 Chew WZ, Teoh WY, Sivanesan N, Loh PS, Shariffuddin II, Ti LK et al.. Bispectral Index (BIS) Monitoring and Postoperative Delirium in Elderly Patients Undergoing Surgery: A Systematic Review and Meta-Analysis With Trial Sequential Analysis. Journal of cardiothoracic and vascular anesthesia 2022. link 11 Whitlock EL, Gross ER, King CR, Avidan MS. Anaesthetic depth and delirium: a challenging balancing act. British journal of anaesthesia 2021. link 12 Heinrich M, Nottbrock A, Borchers F, Mörgeli R, Kruppa J, Winterer G et al.. Preoperative medication use and development of postoperative delirium and cognitive dysfunction. Clinical and translational science 2021. link 13 Miyoshi H, Nakamura R, Noda Y, Yokomi H, Kamiya S, Morio A et al.. Intravenous patient-controlled analgesia does not increase the risk of postoperative delirium compared to patient-controlled epidural analgesia: a propensity score-matched retrospective cohort study. Annals of palliative medicine 2021. link 14 Tawab Saljuqi A, Hanna K, Asmar S, Tang A, Zeeshan M, Gries L et al.. Prospective Evaluation of Delirium in Geriatric Patients Undergoing Emergency General Surgery. Journal of the American College of Surgeons 2020. link 15 Gaetano R, De Filippis R, Caroleo M, Segura-Garcia C, De Fazio P. Postoperative heroin-withdrawal delirium treated with clonazepam after urgent cardiac surgery: a case report. Rivista di psichiatria 2020. link 16 Delp S, Mei W, Spies CD, Neuner B, Aldecoa C, Bettelli G et al.. Clinical practice in the management of postoperative delirium by Chinese anesthesiologists: a cross-sectional survey designed by the European Society of Anaesthesiology. The Journal of international medical research 2020. link 17 Bombardieri AM, Wildes TS, Stevens T, Wolfson M, Steinhorn R, Ben Abdallah A et al.. Practical Training of Anesthesia Clinicians in Electroencephalogram-Based Determination of Hypnotic Depth of General Anesthesia. Anesthesia and analgesia 2020. link 18 Bilotta F, Weiss B, Neuner B, Kramer S, Aldecoa C, Bettelli G et al.. Routine management of postoperative delirium outside the ICU: Results of an international survey among anaesthesiologists. Acta anaesthesiologica Scandinavica 2020. link 19 Jin L, Yao R, Heng L, Pang B, Sun FG, Shen Y et al.. Ultrasound-guided continuous thoracic paravertebral block alleviates postoperative delirium in elderly patients undergoing esophagectomy: A randomized controlled trial. Medicine 2020. link 20 Hughes CG, Boncyk CS, Culley DJ, Fleisher LA, Leung JM, McDonagh DL et al.. American Society for Enhanced Recovery and Perioperative Quality Initiative Joint Consensus Statement on Postoperative Delirium Prevention. Anesthesia and analgesia 2020. link 21 Cheng Q, Li L, Yang M, Sun L, Li R, Huang R et al.. Moderate hypercapnia may not contribute to postoperative delirium in patients undergoing bronchoscopic intervention. Medicine 2019. link 22 Sieber F, Neufeld KJ, Gottschalk A, Bigelow GE, Oh ES, Rosenberg PB et al.. Depth of sedation as an interventional target to reduce postoperative delirium: mortality and functional outcomes of the Strategy to Reduce the Incidence of Postoperative Delirium in Elderly Patients randomised clinical trial. British journal of anaesthesia 2019. link 23 Cao SJ, Chen D, Yang L, Zhu T. Effects of an abnormal mini-mental state examination score on postoperative outcomes in geriatric surgical patients: a meta-analysis. BMC anesthesiology 2019. link 24 Mickle AM, Maybrier HR, Winter AC, McKinnon SL, Torres BA, Lin N et al.. Achieving Milestones as a Prerequisite for Proceeding With a Clinical Trial. Anesthesia and analgesia 2018. link 25 Aldecoa C, Bettelli G, Bilotta F, Sanders RD, Audisio R, Borozdina A et al.. European Society of Anaesthesiology evidence-based and consensus-based guideline on postoperative delirium. European journal of anaesthesiology 2017. link 26 Shin HJ, Koo BW, Bang SU, Kim JH, Hwang JW, DO SH et al.. Intraoperative dexmedetomidine sedation reduces the postoperative agitated behavior in elderly patients undergoing orthopedic surgery compared to the propofol sedation. Minerva anestesiologica 2017. link 27 Li T, Wieland LS, Oh E, Neufeld KJ, Wang NY, Dickersin K et al.. Design considerations of a randomized controlled trial of sedation level during hip fracture repair surgery: a strategy to reduce the incidence of postoperative delirium in elderly patients. Clinical trials (London, England) 2017. link 28 Jeong YM, Lee E, Kim KI, Chung JE, In Park H, Lee BK et al.. Association of pre-operative medication use with post-operative delirium in surgical oncology patients receiving comprehensive geriatric assessment. BMC geriatrics 2016. link 29 Schenning KJ, Deiner SG. Postoperative Delirium in the Geriatric Patient. Anesthesiology clinics 2015. link 30 Whitlock EL, Vannucci A, Avidan MS. Postoperative delirium. Minerva anestesiologica 2011. link 31 Sieber FE, Zakriya KJ, Gottschalk A, Blute MR, Lee HB, Rosenberg PB et al.. Sedation depth during spinal anesthesia and the development of postoperative delirium in elderly patients undergoing hip fracture repair. Mayo Clinic proceedings 2010. link

Postoperative delirium