Τίτλος:
Hypothalamic-pituitary-adrenal axis dysfunction in critically ill
patients with traumatic brain injury: Incidence, pathophysiology, and
relationship to vasopressor dependence and peripheral interleukin-6
levels
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Objective: To investigate hypothalamic-pituitary-adrenal axis function
in patients requiring mechanical ventilation for traumatic brain injury
and to assess the relation of hypothalamic-pituitary-adrenal axis
abnormalities with vasopressor dependence and peripheral cytokine
levels.
Design: Prospective study.
Setting: General intensive care unit in a university teaching hospital.
Patients: Forty patients (33 men and 7 women) with moderate to severe
traumatic brain injury (mean age, 37 +/- 16 yrs) were studied the day
after termination of mechanical ventilation (7-60 days after trauma).
Interventions: First, a morning blood sample was obtained to measure
baseline cortisol, corticotropin, interleukin-6, and tumor necrosis
factor alpha. Subsequently, 1 mug of synthetic corticotropin was
injected intravenously, and 30 mins later, a second blood sample was
drawn to determine stimulated plasma cortisol. Based on data derived
from healthy volunteers, patients having stimulated cortisol levels <18
mug/dL were defined as nonresponders to the low-dose stimulation test.
Thirty-one patients underwent also a human corticotropin releasing
hormone test.
Measurements and Main Results: In traumatic brain injury patients, mean
baseline and low-dose stimulation test-stimulated cortisol levels were
17.2 +/- 5.4 mug/dL and 24.0 +/- 6.6 mug/dL, respectively. The median
increment in cortisol was 5.9 mug/dL Basal corticotropin levels ranged
from 3.9 to 118.5 pg/mL Six of the 40 patients (15%) failed the
low-dose stimulation test The human corticotropin releasing hormone test
(performed in 26 responders and five nonresponders) revealed diminished
cortisol release only in the low-dose stimulation test nonresponder
patients. Corticotropin responses to corticotropin releasing hormone
were consistent with both primary (three patients) and/or secondary (two
patients) adrenal dysfunction. In retrospect, nonresponders to the
low-dose stimulation test more frequently required vasopressors (6/6
[100%] vs. 16/34 [47%]; p = .02) and for a longer time interval
(median, 0 vs. 293 hrs; p = .006) compared with responders. Furthermore,
nonresponders had higher interleukin-6 levels compared with responders
(56.03 vs. 28.04 pg/mL; p = .01), whereas tumor necrosis factor alpha
concentrations were similar in the two groups (2.42 vs. 1.55 pg/mL; p =
.53).
Conclusions: Adrenal cortisol secretion after dynamic stimulation is
deficient in a subset of critically ill patients with moderate to severe
head injury. This disorder is associated with prior vasopressor
dependency and higher interleukin-6 levels.
Συγγραφείς:
Dimopoulou, L
Tsagarakis, S
Kouyialis, AT
Roussou, P and
Assithianakis, G
Christoforaki, M
Ilias, I
Sakas, DE and
Thalassinos, N
Roussos, C
Περιοδικό:
Pediatric Critical Care Medicine
Εκδότης:
Lippincott, Williams & Wilkins
Λέξεις-κλειδιά:
traumatic brain injury; low-dose corticotropin stimulation test; human
corticotropin releasing hormone test; primary adrenal dysfunction;
interleukin-6
DOI:
10.1097/01.CCM.0000108885.37811.CA
