Intensive care unit physicians can increase the success of mechanical ventilation weaning and shorten the weaning period by identifying critically ill patients who have adrenal insufficiency and treating them with the hormone hydrocortisone (cortisol).
These study results appear in the first issue for February 2006 of the American Journal of Respiratory and Critical Care Medicine, published by the American Thoracic Society.
Horng-Chyuan Lin, M.D., of the Department of Thoracic Medicine II at Chang Gung Memorial Hospital in Taipei, Taiwan, and an associate studied 93 critically ill patients who were receiving mechanical ventilation. In an initial evaluation, 23 individuals exhibited normal adrenal function and 70 were diagnosed with adrenal insufficiency.
Because of the high percentage of adrenal insufficiency detected within the study cohort, the authors recommend that all mechanically ventilated patients undergo an adrenal function test before weaning.
The adrenal gland, which plays an important role in stress response, is situated atop the kidney and secrets various hormones essential to the function of many organ systems in the body. Cortisol (hydrocortisone) is an adrenal-cortex hormone used in the treatment of rheumatoid arthritis and other inflammatory conditions.
According to the authors, adrenal insufficiency is a common disorder in critically ill patients who have been mechanically ventilated. For these patients, the problem is usually associated with higher mortality and a poor clinical outcome.
To determine whether corticosteroid supplementation could improve ventilator weaning in those patients with renal insufficiency, the investigators divided the 70 patients into two groups by random computer selection. Thirty-five individuals were treated with hydrocortisone intravenously, while 35 controls received a saline solution.
The successful ventilator weaning percentage was significantly higher in the group that received the hydrocortisone, hitting 91.4 percent, as compared with the placebo group at 68.8 percent. The weaning percentage in those with an adequate adrenal reserve was 88.4 percent.
"Ventilator weaning is the transitional period between total ventilatory support and spontaneous breathing and is a crucial issue in ICUs," said Dr. Lin. "Rapid and successful ventilator weaning can shorten the length of stay, decrease morbidity and mortality, and reduce costs. Although the reasons are unclear, patients requiring reintubation after a failed extubation have a poor prognosis and higher hospital mortality."
In the 35-patient corticosteroid treatment group, 32 were successfully weaned. Among the 35 in the placebo group, 24 were successfully weaned. In the 20-patient adequate adrenal reserve group, 20 were successfully weaned, although three patients failed after having had their breathing tubes removed.
The researchers' results inspired them to develop a larger, multi-center trial of the hormone treatment, which is currently underway, to demonstrate their findings in a larger group.