Elevated plasma antidiuretic hormone levels in status asthmaticus.

Elevated plasma antidiuretic hormone (ADH) levels were noted in seven patients with status asthmaticus during the acute illness. These values returned to normal with resolution of the disease. The mechanism of this release is not completely understood but is consistent with the hypothesis that bronchospasm leads to decreased pulmonary blood flow, decreased volume return to the left atrium, and stimulation of the atrial volume receptors regulating ADH release. Planning for fluid therapy in patients with status asthmaticus should take into account a high probability of increased plasma ADH concentration during the acute illness. Water intoxication as well as hypoxia and hypercarbia should be considered as a possible cause of an altered state of consciousness associated with status asthmaticus.