Emergence delirium after intracranial neurosurgery- a prospective cohort study

The primary objective of this study was to estimate the incidence of emergence delirium (ED) including hypo- and hyperactive ED, after intracranial neurosurgery. Secondary objective was to identify perioperative risk factors of ED in these patients.

This prospective observational study was conducted at an academic neurosciences hospital. All consecutive adult patients (age ≥ 18 years) with a preoperative Glasgow Coma Scale score of 15 undergoing elective intracranial surgery under general anesthesia during the six-month period from October 2020 to March 2021 were included in this study. Perioperative patient data were collected till one hour after surgery. ED was defined as per Riker's sedation agitation score (SAS) as hyperactive ED when SAS was >4 and hypo active ED when SAS was <4 on a 1 to 7 scale.

Data of 320 patients were analyzed in this study. The overall incidence of ED was 22 % (71/320), with incidence of hyperactive ED of 4.3 % (n = 14) and hypoactive ED of 18 % (n = 57). The risk factors for ED were preoperative delirium (odds ratio [OR], 95 % confidence interval [CI] and p value of 4.41, 1.3-15.19, and 0.002), education level (OR = 2.21, [0.98-4.94], p = 0.05), minimum alveolar concentration of inhalational anesthetic (OR = 1.47, [1.17-1.88], p = 0.002), postoperative nausea and vomiting (OR = 4.56, [2.04-10.32], p = 0.001), and body weight (OR = 1.69, [1.1-2.68], p = 0.02). Hyperactive ED was predicted by preoperative delirium (OR = 5.28, [1.12-21.21], p = 0.024) and low education level (OR = 4.35, [1.2-17.04], p = 0.027).

Atleast one in five patients undergoing brain surgery under anesthesia develop ED. Addressing modifiable risk factors might reduce ED.