Secondary adrenal insufficiency in the acute phase of pediatric traumatic brain injury

Abstract

A high incidence of secondary adrenal insufficiency (AI) has been reported several months after a traumatic brain injury (TBI) in pediatric patients. Data from studies in adults suggest that AI may occur during the acute phase of TBI, with potential negative effects in the management of these vulnerable patients. The aim of this study was to describe the prevalence and the characteristics of AI in the acute phase of pediatric TBI. Adrenal function was systematically evaluated in patients admitted to the pediatric intensive care unit following a TBI. Serial measurements of cortisol (9 samples) and adrenocorticotropic hormone (ACTH) were drawn from the second morning to the third morning post admission. Secondary AI was defined as all cortisols < 200 nmol/l (6 μg/dl) with ACTH < 12 pmol/l. Twenty-eight patients (2-15 years old) were evaluated. Secondary AI occurred in ten (36%) patients. AI was more frequent in patients with intracranial hypertension (p < 0.05). Patients with AI required longer mechanical ventilation (p < 0.05), and a non-significant trend for a higher Pediatric Logistic Organ Dysfunction score (p = 0.09) and greater norepinephrine dose (p = 0.11) was observed. Secondary AI is frequent during the acute phase of pediatric TBI, particularly when intracranial hypertension is present. Systematic assessment of pituitary function after TBI appears to be essential. A randomized clinical trial is warranted to evaluate the benefits of hormonal replacement therapy in TBI patients with AI.