Circulatory shock is broadly defined as circulatory failure resulting in the body's inability to maintain organ perfusion and to meet oxygen demands. It usually presents with low blood pressure. Up to every third patient with circulatory shock may be admitted to the intensive care unit because of circulatory failure, and mortality in the intensive care unit ranges from 16% to 60%. For treatment, fluid replacement is followed by vasopressor agents, if necessary. A vasopressor agent is an agent that causes a rise in blood pressure. Vasopressor therapy is an important part of haemodynamic support in patients with shock (where haemodynamics is defined as the flow of blood in the circulatory system). A number of different vasopressors are available.
This systematic review included 23 randomized controlled trials. Overall 3212 patients, with 1629 deaths, were analysed. Six different vasopressors alone or in combination with dobutamine or dopexamine were studied in 11 different comparisons. The strength of evidence differed greatly between several comparisons and the most data are available for norepinephrine. Dopamine seems to increase the risk for heart arrhythmias. In summary, there is not sufficient evidence to prove that any of the vasopressors, in the assessed doses, were superior to others. The choice of a specific vasopressor may therefore be individualized and left to the discretion of the treating physicians.