Association of Preoperative Neutrophil–lymphocyte Ratios with the Emergence Delirium in Pediatric Patients after Tonsillectomy and Adenoidectomy: an Observational Prospective Study

Purpose The study aimed to investigate potential risk factors for emergence delirium (ED) in pediatric patients after tonsillectomy and adenoidectomy (T&A). Methods This prospective, single-center observational study enrolled children aged 3–7 years who underwent T&A under general anesthesia. ED was assessed according to DSM-IV or V criteria. Receiver operating characteristic curve analysis was performed to evaluate the predicative and cut-off values of risk factors, including age, preoperative anxiety level, postoperative pain and neutrophil–lymphocyte ratio (NLR) for ED. Univariate and multivariate logistic regression analyses were performed to investigate risk factors for ED. Results 94 pediatric patients who underwent T&A were enrolled and 19 developed ED (an incidence of 25.3%). Receiver operating characteristic analysis indicated that preoperative NLR was a significant predictor of ED with a cut-off value of 0.8719 and an area under the curve (AUC) of 0.671 (95% confidence interval (CI) 0.546–0.796, P = 0.022). Preoperative NLR (< 0.8719) and postoperative pain were independent risk factors associated with ED (odds ratio: 0.168, 95% CI 0.033–0.858, P = 0.032; odds ratio: 7.298, 95% CI 1.563–34.083, P = 0.011) according to multivariate logistic regression analysis. Conclusions Preoperative NLR level and postoperative pain were independent risk factors for ED in pediatric patients undergoing T&A.