(1650) Pseudoephedrine or Midodrine for the Treatment of Neurogenic Shock

Introduction: Neurogenic shock, a consequence of cervical and high thoracic spinal cord injuries, often results in a loss of sympathetic tone with preserved parasympathetic function. This state of autonomic instability can present clinically as hypotension, bradycardia or a combination of both. Initial treatment includes fluids and intravenous (IV) vasopressor therapy, with a target mean arterial pressure (MAP) greater than 85 mmHg for the first 72 hours after insult. After this period, maintaining a MAP goal greater than 65 mmHg can be challenging due to hypotension and bradycardia related to the injury. Patients are often started on oral agents, midodrine or pseudoephedrine, to maintain a MAP goal greater than 65 mmHg.

Methods: A retrospective, single center chart review of patients with ICD-10 codes for cervical spinal cord injury and shock, defined as inability to maintain a MAP ≥ 65 mmHg without IV vasopressor support 72 hours after admission, from September 2013 to September 2023. Patients were divided into two groups, those who received pseudoephedrine or those who received midodrine. Patients included in the study were greater than 18 years of age and admitted to the Trauma ICU.

Results: A total of 35 patients were included in the primary analysis. Most patients in both treatment groups were male, with 68% in the midodrine group and 86% in the pseudoephedrine group. Although not statistically significant, patients treated with pseudoephedrine were on IV vasopressors for an average of 29 hours, compared to 46 hours for those treated with midodrine (p=0.39). The average ICU length of stay was 13 days for patients treated with pseudoephedrine and 16 days for those treated with midodrine (p=0.28). The average hospital length of stay was 40 days for the pseudoephedrine group compared to 28 days for the midodrine group (p=0.77). At discharge, 64.3% in the midodrine group and 85.7% in the pseudoephedrine group were prescribed an oral agent at discharge (p < 0.001).

Conclusions: Patients with cervical spinal cord injuries may require oral agents, such as midodrine or pseudoephedrine, to maintain a MAP ≥ 65 mmHg. Further evaluation of institutional practices may provide additional insight into the selection of either pseudoephedrine or midodrine.