Mortality and blood pressure in emergency patients with traumatic brain injury: a retrospective cohort study/Mortalidad asociada a la presion arterial de ingreso a urgencias en pacientes con trauma encefalo-craneano: un estudio de cohorte retrospectiva/Mortalidade associada a pressao arterial de entrada a urgencias em doentes com trauma encefalocraneano: um estudo de coorte retrospectiva

Introduction: Blood pressure is of special relevance in patients with traumatic brain injury (TBI) at admission to emergency services, since it is the basis of cerebral perfusion pressure. The purpose of this research was to estimate the association between blood pressure values measured on admission and hospital mortality in patients with TBI. Methods: Retrospective cohort study in patients older than 18 years admitted with TBI to Hospital Pablo Tobon Uribe, in Medellin (Colombia) between January 2012 and January 2014. A multivariate logistic regression model was performed to estimate the independent effect of blood pressure values on mortality. Results: 582 patients with a median age of 36 years (IQR = 25-59) 77.1% of them males (n = 449) were evaluated. Mortality according to categories of systolic blood pressure at admission (150 mmHg) was as follows: 34.6% (18/52), 13.3% (56/421) and 29.4% (32/109), respectively. Univariate analysis showed that blood pressure less than 100 or greater than 150 mm Hg were associated with hospital mortality, but that association lost magnitude and statistical significance (OR = 1.81; 95% CI = 0.94-3.48 and OR = 1.91; 95% CI = 0.86-4.54, respectively) after adjustment by Glasgow coma scale, oxygen saturation and cerebral edema. Conclusions: We did not demonstrate a statistically significant association between blood pressure values at admission to the emergency service and mortality in patients with TBI. KEY WORDS Blood pressure; Comorbidities; Emergency; Intracranial pressure; Mortality; Traumatic brain injury Introduccion: en pacientes con trauma encefalo-craneano (TEC) la presion arterial en el momento de la admision por urgencias tiene una relevancia especial por ser la base de la presion de perfusion cerebral. El proposito de esta investigacion fue estimar la asociacion entre los valores de presion arterial al ingreso a urgencias y la mortalidad hospitalaria en dichos pacientes. Metodos: cohorte retrospectiva en pacientes mayores de 18 anos con diagnostico de TEC admitidos al Hospital Pablo Tobon Uribe entre enero de 2012 y enero de 2014. Se hizo una regresion logistica multivariable para estimar el efecto independiente de los valores de presion arterial en la mortalidad. Resultados: en 582 pacientes la mediana de edad fue 36 anos (rango intercuartilico = 25-59) y el 77,1% (n = 449) eran hombres. La mortalidad segun los valores de presion arterial sistolica al ingreso en las categorias de