Postoperative Delirium: Best Practices Alone May Not Be Enough in Patients With Cognitive Impairment

Would you expect one in three patients with cognitive impairment to develop delirium after surgery, even when best-practice anesthesia protocols are followed? A new observational cohort study highlights a persistent challenge facing perioperative teams: routine adherence to established guidelines may not provide enough protection against delirium for cognitively vulnerable patients.

Study Overview: Examining the Limits of “Best Practices”

This analysis pooled data from 1,255 adults with preoperative cognitive impairment undergoing surgery at a large academic hospital. All stayed at least one postoperative night and underwent formal delirium assessment. Researchers tracked anesthesia-related best practices—covering medication avoidance, glucose and temperature control, hemodynamic management, and anesthetic monitoring—using electronic health record (EHR) data.

Key Findings: Delirium Remains Common Despite High Adherence

One-third (33.9%) of patients developed postoperative delirium, underscoring the ongoing vulnerability of this population.

Adherence to individual best practices such as maintaining blood glucose below 200 mg/dL, using a temperature probe, and keeping body temperature above 36°C was associated with lower delirium odds when analyzed separately.

However, when all best practices were considered together, no single intervention independently reduced delirium risk, except for postoperative glucose monitoring—which paradoxically was linked with higher delirium rates, likely reflecting that higher-risk patients received more intensive monitoring.

The high delirium rate persisted despite most patients having best-practice elements in place, such as avoidance of deliriogenic medications and tight physiologic control.

Clinical Implications: Beyond Guidelines—Toward Personalization

While foundational, current perioperative recommendations may not be enough for cognitively impaired patients. The findings suggest it’s time for anesthesia and surgical teams to rethink a “one-size-fits-all” approach and move toward personalized, multidisciplinary strategies. This could include early identification of high-risk patients through EHR tools, tailored bundles that address cognitive and functional needs, and involving geriatricians, caregivers, and patients themselves in shared decision-making.

Why This Matters for Practice

Delirium is not just a transient inconvenience—it leads to longer hospitalizations, functional decline, and higher healthcare costs.

Routine best practices are essential, but clinicians should recognize their limitations in certain populations and advocate for research and integration of tailored, multimodal prevention strategies.

Leveraging EHR-based identification and embedding scalable interventions into perioperative workflows may help bridge the current gap in delirium prevention.

Conclusion

For patients with cognitive impairment, following established perioperative best practices alone may not be enough to prevent postoperative delirium. Clinicians should look beyond guidelines, embracing technology and multidisciplinary care to better protect this high-risk group.

Key points

One in three surgical patients with cognitive impairment developed postoperative delirium despite best-practice adherence.

Individual best practices (like glucose and temperature control) lowered delirium odds in isolation, but not when combined.

Postoperative glucose monitoring was linked to higher delirium risk, likely due to indication bias.

Routine protocols are foundational but insufficient for cognitively vulnerable populations.

Personalized, multidisciplinary interventions and EHR-based tools may improve delirium prevention.

Citation:

Scharp D, Meyers K, Nadkarni G, et al. Perioperative Best Practices and Delirium in Patients With Cognitive Impairment. JAMA Network Open. 2026;9(3):e261515. doi:10.1001/jamanetworkopen.2026.1515