WIP 37 - Intranasal Baclofen as a Treatment for Paroxysmal Sympathetic Hyperactivity in Patients Admitted to a Pediatric ICU Following New Onset Acquired Brain Injury: A Retrospective Case Control Study

Publication Number: WIP 37.7563

Jacquelyn Benner, Rady Children's Hospital San Diego, SAN DIEGO, CA, United States; Andrew Skalsky, Rady Children's Hospital San Diego, San Diego, CA, United States; Helen Harvey, Rady Children’s Hospital/ UC San Diego, San Diego, CA, United States; Nicole Coufal, University of California, San Diego School of Medicine, San Diego, CA, United States; Jennifer Foley, Rady Children's Hospital San Diego, San Diego, CA, United States; Zaineb Boulil, Rady Children's Hospital San Diego, San Diego, CA, United States; Alyssa Wieand, Rady Children's Hospital San Diego, San Diego, CA, United States

Background: Paroxysmal sympathetic hyperactivity (PSH) occurs after brain injury and is associated with overactive sympathetic tone manifested by tachycardia, hypertension, tachypnea, hyperthermia, hypertonia and diaphoresis. PSH affects roughly 13% of children with severe brain injury, representing a treatable contributor to secondary injury. Baclofen has shown promise as a treatment option via enteral or intrathecal (IT) routes, however both have challenges, including poor blood brain barrier (BBB) penetration enterally and surgical/infectious complications with IT delivery. Intranasal (IN) baclofen bypasses the BBB for nonsurgical delivery leading to lower dosing and potential for reduced side effects such as lethargy, bradycardia, and hypotension.

Objective: We aim to determine the efficacy of IN baclofen as a treatment for PSH in pediatric patients following acute brain injury. The primary endpoint is reduction in a modified clinical feature scale (CFS) score adapted from Corroza et al.

Design/Methods: This is an IRB exempt retrospective case control study on patients aged 0-21 years admitted to a PICU from Jan 1, 2000 to Apr 4, 2024 with new onset acquired brain injury clinically diagnosed with PSH comparing those treated with IN baclofen to those who were not. Of those treated with IN baclofen 22 patients met inclusion criteria. Demographics, GCS, admission diagnosis, PICU days, ventilator days, sedation, antibiotics, cultures, vital signs and tone data were collected. CFS score was modified to include only vital sign parameters (heart rate, respiratory rate, systolic blood pressure, temperature) given inconsistent charting of tone and diaphoresis. Dose/time of IN baclofen was obtained as well as shift level indicators for other PSH medications over 5 days. A multilevel model was used to estimate the effect of IN baclofen on CFS score with a 95% confidence interval. Number of ventilator days and PICU days were compared between the case and control groups using a t-test or Wilcoxon rank-sum test for continuous data and a chi-square or Fischer’s exact test for ordinal data.