[Vasopressin and its analogues in the therapy of shock]

Hemodynamic support during the circulatory failure with vasodilation, most frequently during the septic shock, is based on volume recovery and administration of inotropic drugs. If such therapy is not sufficient, vasoconstriction drugs are subsequently or parallel added to maintain the perfusion pressure. As a standard therapy, norepinephrine or other catecholamines with alpha-adrenergic effect are used in rising doses. Some patients do not respond to such therapy with desired hemodynamic changes--they develop catecholamine resistant shock. Because of serious side effects of high doses of catecholamines, alternative vasopressors are necessary. Vasopressin, antidiuretic hormone, has in physiological conditions only minimal effect of the vascular tone. During hypovolemia its concentration rises and it may significantly contribute to the maintenance of arterial pressure by vasoconstriction. Contrary to it, during septic shock the levels of vasopressine are very low and vasodilation clinically dominates. At the same time, the septic shock is accompanied by an increased sensitivity to vasopressin administration. In a critical shock a serious deficit of endogenous vasopressin is expected. At present several pilot studies with vasopressine administration in septic shock exist in literature describing beneficial effect of vasopressin on hemodynamic parameters. Such comparatively low doses have no side effects on perfusion and function of body organs. Terlipressin, which is available in Czech Republic, is a synthetic analogue of vasopressin with extended effect. Its intermittent administration is used for the treatment of portal hypertension complications. Terlipressin in animal model of septic shock has similarly beneficial effects as vasopressin. High doses of Terlipressin have, similarly to vasopressin, adverse effects on pulmonary circulation and other systems. Till present, only casuistic experience has been published with low doses of Terlipressin in the treatment of septic shock resistant to catecholamines, which has shown similar effects to vasopressin. In shock states with the deficit of endogenous vasopressin, which are resistant to high doses of catecholamines, administration of vasopressin analogues represents a new perspective therapy. The treatment should be studied from the point of morbidity and mortality. A careful approach has to be used in septic patients with pre-existing obliterative vassal disease.