Hypernatremia and Coagulopathy May or May Not Be Useful Clinical Biomarkers in Dogs with Head Trauma: A Retrospective Study

This study was performed to evaluate clinical biomarkers as prognostic values in dogs with traumatic brain injury (TBI) based on findings in human patients. Sodium levels of 158 dogs with TBI and 169 patients with trauma without involvement of the head except head trauma (EHT) were examined. TBI patients with hypernatremia had a slightly higher risk of dying (22.03 %) than dogs with normal sodium levels (19.76%). However, there was no significant correlation between sodium levels and outcome in TBI patients (p=0.6357). Dogs with sodium levels >160mmol/L were non-survivors. In dogs with late-onset post-traumatic epilepsy (PTE) more often hyponatremia was measured, and in dogs with immediate PTE mild hypernatremia or normal sodium levels were measured after the trauma. Evaluation of coagulation parameters in a subpopulation of dogs showed a strong correlation between partial thromboplastin time/prothrombin time (PTT/PT) and the Modified Glasgow Coma Scale (MGCS) (p=0.0006; p=0.0306). In conclusion, unlike in human patients, sodium levels displayed no significant correlation with survival in dogs with TBI in the current study. However, in cases with severe TBI, dog owners often elect euthanasia before severe hypernatremia can be measured. Late PTE was observed in cases with initial hyponatremia. Because of a significant correlation between PTT/PT and MGCS, coagulopathy might be considered as a prognostic clinical biomarker in canine TBI patients.