Anesthetic Practice Trends and Perceptions Toward Postoperative Delirium: A Mixed-Methods Analysis

Abstract

Background: Delirium is the most common postoperative complication in older adults, though anesthesiologist awareness of delirium prevention guidelines-and associated practice trends-remains unknown.

Methods: This was a convergent mixed-methods study, which simultaneously analyzed quantitative and qualitative data to determine delirium guideline awareness among anesthesiologists and practice patterns based on guideline recommendations. Quantitative data were abstracted from the Multicenter Perioperative Outcomes Group database for noncardiac surgery patients (2009-2020) aged 65 years and older. Linear trends were reported for select guideline-based delirium prevention recommendations via regression modeling. Anesthesiologists (n = 40) from a major academic center without a structured delirium reduction program on hospital wards were then surveyed regarding knowledge and practices with respect to postoperative delirium. For qualitative data, 3 focus groups were held to further discuss guideline awareness and identify challenges with delirium prevention.

Results: Quantitative results demonstrated a significant decline in the proportion of cases with midazolam between 2009 and 2020, with the largest decrease observed with urologic surgeries (-3.9%/y; 95% confidence interval [CI], -4.2 to -3.6; P < .001). Use of regional anesthesia increased over this period, particularly with gynecologic surgeries (+2.3%/y; 95% CI, 1.2-3.4; P = .001). Anesthesiologist survey results revealed variable guideline awareness, as 21 of 39 (54%) respondents reported being aware of guidelines for anesthetic management of older adults. Importantly, unawareness of delirium management guidelines was the most frequently cited challenge (17 of 37, 46%) when caring for older adults. Finally, focus group participants were largely unaware of postoperative delirium guidelines. However, participants conveyed key barriers to delirium identification and prevention, including the unclear pathophysiology, nonmodifiable risk factors, and system-based hospital challenges. Participants also expressed a desire for decision-support systems, integrated within the perioperative workflow, that provide evidence-based recommendations for reducing delirium risk.

Conclusions: Perioperative practice trends are indicative of an improving environment for postoperative delirium. However, delirium guideline awareness remains variable among anesthesiologists, and key barriers continue to exist for identifying and preventing postoperative delirium.

Figure 1.

Study flow diagram presented. After initial screening and case removal, surgical subspecialty cases were identified via Current Procedural Terminology codes (see Supplementary Appendix (SDC 3) for specific codes). Abbreviations: MPOG = Multicenter Perioperative Outcomes Group; CPT, Current Procedural Terminology; GI = gastrointestinal.

Figure 2.

Trends presented for select perioperative practices of relevance to delirium, outlined in delirium prevention guidelines (see texts for details). The trends reflect the proportion of cases, on an annual basis, receiving a given perioperative intervention (e.g., midazolam administration, peripheral nerve block, etc.) that may impact delirium risk. Data are presented for (A) gastrointestinal/abdominal surgery, (B) gynecologic, (C) urologic, and (D) orthopedic surgery over the time period sampled. For a given year (e.g., 2009), the sampling period began in December of that year through November of the following year. The proportion of cases with perioperative midazolam consistently decreased across all surgical subtypes over the time period studied, and regional anesthetic techniques increased over time. Increased EEG use would be consistent with certain guidelines and recommendations (see text for details). Abbreviation: GI, gastrointestinal; EEG = electroencephalography.