Emergence delirium (AKA “perioperative neurocognitive disorder”) is common. We’ve all seen, treated, and/or attempted to prevent it. Common perioperative risk factors include patient age, gender, preoperative anxiety, type of surgery, anesthetic technique, and postoperative pain.1 Although we often tell ourselves (and the PACU nurses and parents if they are present) that it’s self-limited and the child will neither remember nor suffer ill effects from it, what if that’s not the case? Today’s PAAD discusses the association of emergence delirium with behavioral changes after hospital discharge and is the maiden reviewer voyage for Dr. Audra Webber. Audra joined the PAAD’s executive council at the October SPA/ASA meeting and is an Associate Professor of Anesthesiology and Perioperative Medicine at the University of Rochester Medical Center and the Program Director of the pediatric anesthesiology fellowship.
Oh, and one more thing as you enjoy your morning coffee reading this; I’ve edited out the abbreviation ED throughout the PAAD and spelled out emergence delirium instead. For some of us “ED” (and the little blue pill that often goes with it) means something completely different! Myron Yaster MD
Original Article
Kim J, Byun SH, Kim JW, Kim JY, Kim YJ, Choi N, Lee BS, Yu S, Kim E. Behavioral changes after hospital discharge in preschool children experiencing emergence delirium after general anesthesia: A prospective observational study. Paediatr Anaesth. 2021 Oct;31(10):1056-1064. PMID: 34309126.
Almost 70 years ago, Dr. James Eckenhoff at the University of Pennsylvania recognized that many children experienced postoperative behavioral changes after an anesthetic.2 Since that original publication, many studies have found a link between children with heightened preoperative anxiety and negative postoperative postprocedural behavioral changes.3,4 Dr. Zeev Kain and his colleagues at Yale in a landmark series of studies demonstrated that children with increased preoperative anxiety were more likely to experience both emergence delirium and new onset maladaptive behavioral changes post-operatively.4-7 They also demonstrated that preoperative anxiolysis with midazolam significantly decreased the number of children experiencing negative behavioral changes in the first postoperative week and was better than parental presence for facilitating a smooth mask induction of anesthesia. 8
Todays’ original article by Kim et al., once again looks at the association between emergence delirium and behavioral changes 1 week after elective surgery. Of the 100 ASA physical status 1-2 children, 2 to 7 years of age enrolled in the study, 58 experienced emergence delirium as determined by the PAED and Watcha scales. The authors found that children with emergence delirium experienced more severe behavioral changes 1 week after surgery than those without. They also found, like Kain et al. found previously9 , that “high preoperative anxiety level and emergence delirium scores were associated with posthospital behavioral changes”.
Why did emergence delirium occur so frequently in this study? The authors surmise that this was because the majority of the patients enrolled in the study underwent otorhinolaryngologic and ophthalmologic surgeries under sevoflurane anesthesia, surgeries and an anesthetic technique that are well known to have a high incidence of emergence delirium.1 Additionally, there are several limitations in this study. First, no medications like dexmedetomidine were given to patients to specifically treat or prevent delirium. Second, longer term effects (greater than 1 week) were not studied and remain unknown. Third, premedication was not standardized and choice of drug, dosage and route were left to the anesthesiologists’ discretion - although there was no difference between the emergence delirium and non-emergence delirium groups in the use of premedication. In addition, the pain scores in the Emergence Delirium group were significantly higher than in the non-Emergence Delirium group.
A final issue raised by the authors is the lack of assessment for hypoactive delirium, a relatively new subset of emergence delirium that is thought to be frequently overlooked.
Hypoactive delirium is present “when an awake child is unaware of his or her surroundings, is unable to focus attention, and appears quiet and withdrawn. This condition has been well-described in the intensive care setting but has not been extensively studied in the immediate post-anesthetic period”.10 Therefore any association of hypoactive delirium with postoperative behavioral changes is unknown in this study (and most preceding studies of emergence delirium). Like the authors, I have never heard of this before and would not have recognized it. Have many of you?
I included the reference for those of you who may be interested.10 Finally, there were several methodological issues with this study, perhaps most importantly: the small number of patients studied, the low parental response rate for the postoperative CBCL (child behavior checklist) (74%), and the co-mingling of patients who were premedicated. This study supports the original findings of Kain et al. in the association of emergence delirium with postoperative behavioral changes, but it was not designed to establish causation. Does emergence delirium result in more severe postoperative behavioral changes or is it another correlate of anxious personality type? That question remains unanswered.
What is important about this study is the next steps its findings suggest - whether or not decreasing the incidence of emergence delirium will also decrease the incidence or severity of postoperative behavioral changes, making this an attractive target for future research. If that ends up to be the case, I can foresee a future in which prevention of emergence delirium is as ingrained into pediatric anesthesia practice as preoperative anxiolysis and PONV prophylaxis is today. Finally, this study is a timely reminder that our anesthetic choices impact our patients well beyond discharge, and that we need to address postoperative behavioral changes in our discussions with parents.
Audra M. Webber, MD
References
1. Urits I, Peck J, Giacomazzi S, Patel R, Wolf J, Mathew D, Schwartz R, Kassem H, Urman RD, Kaye AD, Viswanath O: Emergence Delirium in Perioperative Pediatric Care: A Review of Current Evidence and New Directions. Adv Ther 2020; 37: 1897-1909
2. Eckenhoff JE: Relationship of anesthesia to postoperative personality changes in children. AMA Am J Dis Child 1953; 86: 587-91
3. Pearce JI, Brousseau DC, Yan K, Hainsworth KR, Hoffmann RG, Drendel AL: Behavioral Changes in Children After Emergency Department Procedural Sedation. Acad Emerg Med 2018; 25: 267-274
4. Kain ZN, Mayes LC, Caldwell-Andrews AA, Karas DE, McClain BC: Preoperative anxiety, postoperative pain, and behavioral recovery in young children undergoing surgery. Pediatrics 2006; 118: 651-8
5. Min CB, Kain ZN, Stevenson RS, Jenkins B, Fortier MA: A randomized trial examining preoperative sedative medication and postoperative sleep in children. J Clin Anesth 2016; 30: 15-20
6. Kain ZN, Caldwell-Andrews AA, Maranets I, McClain B, Gaal D, Mayes LC, Feng R, Zhang H: Preoperative anxiety and emergence delirium and postoperative maladaptive behaviors. Anesth Analg 2004; 99: 1648-1654
7. Kain ZN, Mayes LC, Wang SM, Caramico LA, Hofstadter MB: Parental presence during induction of anesthesia versus sedative premedication: which intervention is more effective? Anesthesiology 1998; 89: 1147-56; discussion 9A-10A
8. Kain ZN, Mayes LC, Wang SM, Caramico LA, Hofstadter MB: Parental presence during induction of anesthesia versus sedative premedication: which intervention is more effective? Anesthesiology 1998; 89: 1147-56; discussion 9A-10
9. Kain ZN, Mayes LC, O'Connor TZ, Cicchetti DV: Preoperative anxiety in children. Predictors and outcomes. Arch.Pediatr.Adolesc.Med. 1996; 150: 1238-1245
10. Lee-Archer PF, von Ungern-Sternberg BS, Reade MC, Law KC, Long D: An observational study of hypoactive delirium in the post-anesthesia recovery unit of a pediatric hospital. Paediatr Anaesth 2021; 31: 429-435