The Incidence and Risk Factors for Hypotension During Emergent Decompressive Craniotomy in Children with Traumatic Brain Injury Patrick Miller, MD* Christopher D. Mack, MS Marla Sammer, MD‡ Irene Rozet, MD* Lorri A. Lee, MD* Saipin Muangman, MD* Marjorie Wang, MD, MPH§ Will Hollingworth, PhD‡ Arthur M. Lam, MD, FRCPC*§ Monica S. Vavilala, MD*†§ We conducted a retrospective cohort study in children 13 yr with traumatic brain injury (TBI) at a Level 1 pediatric trauma center to describe risk factors for intraoperative hypotension (IH) during emergent decompressive craniotomy. Between 1994 and 2004, 108 children underwent emergent decompressive craniot- omy for TBI. Overall, 56 (52%) patients had IH. Independent risk factors for IH were each 10 mL estimated blood loss/kg (ARR 1.15 95% CI 1.08 –1.22), each mm of computed tomography (CT) midline shift (ARR 1.04 95%CI 1.01–1.07), each 10 mL of CT lesion volume (ARR 1.03 95%CI 1.01–1.05), and emergency department (ED) hypotension (5/5 patients with ED hypotension had IH). CT midline shift 4 mm predicted IH (ARR 1.67 95% CI 1.06 –2.63), independent of blood loss. IH occurred frequently during emergent decompressive craniotomy in children with TBI. ED hypotension, blood loss, CT lesion volume, and CT midline shift predicted IH. Anesthesiologists can expect children with preoperative CT midline shift 4 mm to have IH during this procedure. (Anesth Analg 2006;103:869 –75) Hypotension after initial traumatic brain injury (TBI) may lead to secondary brain injury and worsen outcome (1–7). Patients with TBI, who undergo decompressive craniotomy, may be at particular risk of intraoperative hypotension (IH) due to blood loss, inadequate intravas- cular volume resuscitation, changes in sympathetic tone and/or general anesthesia. However, the incidence and risk factors for IH during this procedure in children with TBI are not well described. There is only one study describing arterial blood pressure changes during decompressive craniotomy in children. In 1982, Uchida et al. (8) reported hypo- tension in children who underwent emergent evacua- tion of intracranial mass lesions between 1964 and 1976. Of the 36 children, aged 2 mo to 9 yr, 41% had hypotension during emergent evacuation of subdural hematoma (SDH), subdural hygroma, or subdural effusion. Five patients had at least one episode of unmeasurable arterial blood pressure, and one child developed cardiac arrest. Of the risk factors considered, hypotension was associated with young age—infancy, in particular—and hematoma size larger than 8% of intravascular volume on head computed tomographs (CT). However, there were very few (5/36) children older than 5 yr of age, and non-SDH intracranial mass lesions were not considered. Additionally, hypoten- sion attributable to blood loss was not considered, and intravascular volume calculation was based on theo- retical age-related normative values rather than an estimate of intravascular volume at the time of sur- gery. Since publication of their study in Critical Care Medicine more than 20 yr ago, there has been no further characterization of the impact of decompressive cra- niotomy on arterial blood pressure in children. To provide more information on IH in children with traumatic intracranial mass lesions requiring neuro- surgical intervention, we aimed to describe the inci- dence and the risk factors for IH during emergent pediatric decompressive craniotomy. METHODS After IRB approval, a list of children 13 yr who underwent emergent decompressive craniotomy over From the Departments of *Anesthesiology, †Pediatrics, ‡Radiol- ogy, and §Neurological Surgery, University of Washington, Seattle, Washington; and Harborview Injury Prevention and Research Center, Seattle, Washington. Accepted for publication June 5, 2006. Supported by NIH/NICHD Grant K23044632 and Harborview Injury prevention and Research Center, Seattle, WA. Address correspondence and reprint requests to Monica S. Vavilala, MD, Department of Anesthesiology, Harborview Medical Center, 325 Ninth Avenue, Box 359724, Seattle, WA 98104. Address e-mail to vavilala@u.washington.edu. Copyright © 2006 International Anesthesia Research Society DOI: 10.1213/01.ane.0000237327.12205.dc Vol. 103, No. 4, October 2006 869