Association of preoperative neutrophil-to-lymphocyte ratio with the risk of emergence delirium in children undergoing dental treatment under general anesthesia

Background: Emergence delirium (ED) is a common postoperative complication in pediatric patients, characterized by confusion, agitation, and restlessness. Recent studies suggest that systemic inflammation, particularly the neutrophil-to-lymphocyte ratio (NLR), may play a role in its development. This study aimed to assess the relationship between preoperative peripheral blood parameters, especially NLR, and the incidence of ED in pediatric patients undergoing dental treatment under general anesthesia. Methods: This retrospective, single-center study included 102 pediatric patients (aged 1–7 years) classified as ASA I or II, who underwent dental procedures under general anesthesia at Ankara Medipol University Dental Hospital between January 2023 and July 2024. Preoperative blood tests, including NLR, were collected. ED was evaluated using the Pediatric Anesthesia Emergence Delirium (PAED) Scale. Statistical analyses included Chi-square, Mann-Whitney U tests, multivariate logistic regression, and receiver operating characteristic (ROC) curve analysis. Results: ED occurred in 18 of 102 patients (17.6%). Univariate analysis showed a significantly higher mean NLR in patients with ED (2.0 ± 1.55) compared to those without ED (0.87 ± 0.30)(p < 0.001). However, multivariate logistic regression did not identify NLR or other variables as independent predictors of ED. ROC curve analysis yielded an NLR cut-off of 1.005, with sensitivity 23.1% and specificity 76.3% (Area under the curve (ACU) = 0.234, p < 0.05). Other inflammatory markers, including monocyte-to-lymphocyte ratio (MLR) and platelet-to-lymphocyte ratio (PLR), also showed significant associations with ED in univariate analyses. Conclusions: Although significant associations between preoperative inflammatory markers and ED were observed in univariate analyses, these markers did not remain independent predictors in multivariate analysis. Nonetheless, the identified correlations highlight the potential role of preoperative inflammatory markers in identifying pediatric patients at increased risk of ED, underscoring the need for further research to establish their clinical utility.

Delirium; Blood tests; General anesthesia; Pediatric dentistry; Pediatric anesthesia

[1] Knapp R, Marshman Z, Rodd H. Treatment of dental caries under general anesthetic in children. BDJ Team. 2017; 4: 116.

[2] Bajwa SA, Costi D, Cyna AM. A comparison of emergence delirium scales following general anesthesia in children. Pediatric Anesthesia. 2010; 20: 704–711.

[3] Jooma Z, Perrie H, Scribante J, Kleyenstuber T. Emergence delirium in children undergoing dental surgery under general anesthesia. Pediatric Anesthesia. 2020; 30: 1020–1026.

[4] Dechnik A, Traube C. Delirium in hospitalised children. The Lancet Child & Adolescent Health. 2020; 4: 312–321.

[5] Mason KP. Paediatric emergence delirium: a comprehensive review and interpretation of the literature. British Journal of Anaesthesia. 2017; 118: 335–343.

[6] Sikich N, Lerman J. Development and psychometric evaluation of the pediatric anesthesia emergence delirium scale. The Journal of the American Society of Anesthesiologists. 2004; 100: 1138–1145.

[7] Feng B, Guo Y, Tang S, Zhang T, Gao Y, Ni X. Association of preoperative neutrophil-lymphocyte ratios with the emergence delirium in pediatric patients after tonsillectomy and adenoidectomy: an observational prospective study. Journal of Anesthesia. 2024; 38: 206–214.

[8] Su X, Wang J, Lu X. The association between Monocyte‐to‐Lymphocyte ratio and postoperative delirium in ICU patients in cardiac surgery. Journal of Clinical Laboratory Analysis. 2022; 36: e24553.

[9] Pieters BJ, Penn E, Nicklaus P, Bruegger D, Mehta B, Weatherly R. Emergence delirium and postoperative pain in children undergoing adenotonsillectomy: a comparison of propofol vs sevoflurane anesthesia. Pediatric Anesthesia. 2010; 20: 944–950.

[10] Dogruel F, Gonen ZB, Gunay-Canpolat D, Zararsiz G, Alkan A. The Neutrophil-to-Lymphocyte ratio as a marker of recovery status in patients with severe dental infection. Medicina Oral Patologia Oral y Cirugia Bucal. 2017; 22: e440.

[11] Bahrani-Mougeot FK, Thornhill M, Sasser H, Marriott I, Brennan MT, Papagerakis S, et al. Systemic host immuno-inflammatory response to dental extractions and periodontitis. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology. 2008; 106: 534–541.

[12] Beringer RM, Segar P, Pearson A, Greamspet M, Kilpatrick N. Observational study of perioperative behavior changes in children having teeth extracted under general anesthesia. Pediatric Anesthesia. 2014; 24: 499–504.

[13] Keles S, Kocaturk O. The effect of oral dexmedetomidine premedication on preoperative cooperation and emergence delirium in children undergoing dental procedures. BioMed Research International. 2017; 2017: 6742183.

[14] Dong W, Zhang W, Er J, Liu J, Han J. Comparison of laryngeal mask airway and endotracheal tube in general anesthesia in children. Experimental and Therapeutic Medicine. 2023; 26: 554.

[15] Oyama T, Kinoshita H, Takekawa D, Saito J, Hirota K. Higher neutrophil-to-lymphocyte ratio, mean platelet volume, and platelet distribution width are associated with postoperative delirium in patients undergoing esophagectomy: a retrospective observational study. Journal of Anesthesia. 2022; 36: 58–67.

[16] Jiang X, Shen Y, Fang Q, Zhang W, Cheng X. Platelet-to-lymphocyte ratio as a predictive index for delirium in critically ill patients: a retrospective observational study. Medicine. 2020; 99: e22884.

[17] Egberts A, Mattace-Raso FUS. Increased neutrophil-lymphocyte ratio in delirium: a pilot study. Clinical Interventions in Aging. 2017; 12: 1115–1121.

[18] Monk TG, Price CC. Postoperative cognitive disorders. Current Opinion in Critical Care. 2011; 17: 376–381.

[19] Southam-Gerow MA, Flannery-Schroeder EC, Kendall PC. A psychometric evaluation of the parent report form of the state-trait anxiety inventory for children—trait version. Journal of Anxiety Disorders. 2003; 17: 427–446.

[20] Voepel-Lewis T, Zanotti J, Dammeyer JA, Merkel S. Reliability and validity of the face, legs, activity, cry, consolability behavioral tool in assessing acute pain in critically ill patients. American Journal of Critical Care. 2010; 19: 55–61.

[21] Gamble JJ. Emergence delirium in pediatric anesthesia: the urgent need for evidence-based guidelines. Canadian Journal of Anesthesia. 2015; 72: 373–377.

[22] Aoyama K, Furuta M, Ameye L, Petre MA, Englesakis M, Rana M, et al. Risk factors for pediatric emergence delirium: a systematic review. Canadian Journal of Anesthesia. 2025; 72: 384–396.