Emerging role of vasopressin.

Ionotropic agents are frequently used in vasodilatory shock like conditions of septic or nonseptic origin. Conventional catecholamines such as norepinephrine are used at a very high dose with possibility of adverse effects in many patients. One often encounters refractoriness to these drugs. Infusion of vasopressin (VP) which is detectable at inappropriately low level in advanced phase of septic shock might allow withdrawal of catecholamines, as it maintains adequate mean arterial pressure (MAP), improves urine output and leaves perfusion of vital organs unhindered. Vasopressin has been found to be superior to epinephrine in animal models and some human trials, especially in patients with resistant ventricular fibrillation (VF) while doing cardiopulmonary resuscitation (CPR). Analogues of VP have also been used for diuresis in patients of hepatorenal syndrome.