Introduction: Adrenomedullin is a recently discovered vasoactive peptide. Infusion of adrenomedullin increases regional cerebral blood flow and reduces infarct volume after vascular occlusion in rats1. In humans, increased cerebral adrenomedullin has been identified in patients following cardiopulmonary bypass and subarachnoid hemorrhage2,3. Following traumatic brain injury (TBI) in children, cerebral hypoperfusion is frequently observed and is associated with poor outcome4. We hypothesized that adrenomedullin levels would be increased in cerebrospinal fluid (CSF) of children following severe TBI. Methods: Total adrenomedullin concentrations were measured using a radioimmunometric assay, by investigators blinded to patient identification. Ventricular CSF samples (n=36) were collected from 10 children during the first 10 d after severe TBI (GCS <8). Control CSF was obtained from 5 children undergoing lumbar puncture, who had normal CSF parameters and no evidence of CNS infection. Patients underwent standard neurointensive care, including CSF drainage. Data were analyzed using a univariate regression model. Results: Adrenomedullin concentration was markedly increased in CSF of children following TBI vs control (mean level 10.65 vs 1.51 fmol/ml, p=0.006). All 36 case samples had an adrenomedullin concentration above the median value for the controls (1.52 fmol/ml). Conclusion: We conclude that the vasoactive peptide, adrenomedullin, is increased in the CSF of children following TBI. We speculate that adrenomedullin participates in the endogenous response to cerebral hypoperfusion after TBI.
ASJC Scopus subject areas
- Critical Care and Intensive Care Medicine