Postoperative delirium

Abstract

Delirium can be defined as an 'acute brain dysfunction.' Compared to dementia, which is a disease that deteriorates the brain function chronically, delirium shows very similar symptoms but is mostly ameliorated when the causative factors are normalized. Due to the heterogeneity in etiologies and symptoms, people including health care workers often mistake delirium for dementia or other psychiatric disorders. Delirium has attracted global interest increasingly and a vast amount of research on its management has been conducted. Experts in the field have constantly suggested that systematic intervention should be implemented through a team-based multicomponent approach aimed to reduce the incidence and duration of delirium. Surgery involves many health care workers with different expertise who are not familiar with delirium. For a team-based approach on the management of delirium, it is vital that all medical personnel concerned have a common understanding of delirium and keep in constant communication. Postoperative delirium is a common complication and exerts an enormous burden on patients, their families, hospitals, and public resources. To alleviate this burden, this article aimed to review general features and the latest evidence-based knowledge of delirium with a focus on postoperative delirium.

Keywords: Cognitive decline; Current practice; Delirium; Postoperative complication; Prevention; Prognosis; Risk factor.

Fig. 1.

Topological data analysis of patient-patient networks for psychological risk factors in postoperative delirium. Filter metric was subdivided into 8 intervals with 80% overlap. Several nodes were disconnected from the main graph. An inset graph in the bottom right represents a lower resolution topology with 4 intervals and 60% overlap. Subgroup G₁ includes 7 delirious patients with low Mini-Mental State Examination (MMSE) scores and regional anesthesia and G₂ includes 4 delirious patients with medium MMSE scores, high neuroticism, and low conscientiousness scores. G₀ includes 6 patients with high MMSE, low neuroticism, and high conscientiousness scores. Adapted from Shin et al. [47] with permission.

Fig. 2.

Delirium recovery rate according to the time course. The graph shows the time course of delirium recovery among 88 patients whose delirium was resolved during hospitalization (72%). The proportion of patients with delirium decreased with increasing length of delirium duration. A total of 39 days were required for medical patients to recover, versus 16 days and 77 days for postoperative and postoperativedelayed patients who recovered during hospitalization, respectively. Adapted from Kim et al. [73] with permission.

Fig. 3.

Treatment response rate between young-old and old-old groups in the 4 antipsychotic groups. *P < 0.05 by Chi-square test or Fisher’s exact test. Treatment response was defined as a ≥ 50% reduction from the baseline score on the Korean version of the Delirium Rating ScaleRevised-98 (DRS-R98-K) [21]. DRS-R98-K is evaluates the presence and severity of delirium. This figure is adapted from Yoon et al. [81] with permission.