Background: Cervical spinal cord injury (CSCI) is often complicated by autonomic instability and life-threatening bradycardia. β-adrenergic receptors offer a potential target for modulating cardiac vagal activity and heart rate. Enteral albuterol may mitigate symptomatic bradycardia in CSCI patients. The purpose of this study was to examine the effect of enteral albuterol on the frequency of symptomatic bradycardia and the need for rescue therapy in CSCI patients.
Methods: The charts of CSCI patients admitted to a Level I trauma center from February 2008 through March 2012 were reviewed for demographics, episodes of symptomatic bradycardia (defined as heart rate < 60 beats per minute and systolic blood pressure < 90 mm Hg), use of enteral albuterol, hospital days requiring chronotropic use, and total atropine administered. In the albuterol group, patients received scheduled enteral albuterol after experiencing symptomatic bradycardia, with chronotropic agents used as needed for rescue treatment. In the no-albuterol group, only chronotropic agents were used as needed for rescue treatment. The albuterol and no-albuterol groups were compared using independent-samples Kruskal-Wallis test for total number of bradycardic episodes, hospital days requiring chronotropic use, and total atropine administered.
Results: Eighteen patients with CSCI-induced bradycardia were identified. Eight patients received treatment with enteral albuterol, and 10 patients did not. The median age did not differ significantly between the two groups. However, the median Injury Severity Score (ISS) was higher in the albuterol group (median ISS, 36.5; interquartile range, 35-66.5 vs. median ISS 26; interquartile range, 27-37.25 in no-albuterol group). Patients receiving albuterol experienced 1.8 symptomatic bradycardic episodes versus 4.3 episodes in those patients not receiving albuterol (p = 0.08). Hospital days on chronotropic agents were significantly less in the albuterol group (1.8 vs. 8.6, p = 0.01). One patient, in the no-albuterol group, required pacemaker placement.
Conclusion: Enteral albuterol may reduce the frequency of symptomatic bradycardia in patients with CSCI, resulting in less rescue therapy using chronotropic agents.
Level of evidence: Therapeutic study, level IV.