Vasopressors for hypotensive shock
Abstract
Background
Initial goal directed resuscitation for shock usually includes the administration of intravenous fluids, followed by initiating vasopressors. Despite obvious immediate effects of vasopressors on haemodynamics their effect on patient relevant outcomes remains controversial. This review was originally published in 2004 and was updated in 2011.
Objectives
Our primary objective was to assess whether particular vasopressors reduce overall mortality, morbidity, and health‐related quality of life.
Search methods
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 2), MEDLINE, EMBASE, PASCAL BioMed, CINAHL, BIOSIS, and PsycINFO (from inception to March 2010). The original search was performed in November 2003. We also asked experts in the field and searched meta‐registries for ongoing trials.
Selection criteria
Randomized controlled trials comparing various vasopressor regimens for hypotensive shock.
Data collection and analysis
Two authors abstracted data independently. Disagreement between the authors was discussed and resolved with a third author. We used a random‐effects model for combining quantitative data.
Main results
We identified 23 randomized controlled trials involving 3212 patients, with 1629 mortality outcomes. Six different vasopressors, alone or in combination, were studied in 11 different comparisons.
All 23 studies reported mortality outcomes; length of stay was reported in nine studies. Other morbidity outcomes were reported in a variable and heterogeneous way. No data were available on quality of life or anxiety and depression outcomes. We classified 10 studies as being at low risk of bias for the primary outcome mortality; only four studies fulfilled all trial quality items.
In summary, there was no difference in mortality in any of the comparisons between different vasopressors or combinations. More arrhythmias were observed in patients treated with dopamine compared to norepinephrine. Norepinephrine versus dopamine, as the largest comparison in 1400 patients from six trials, yielded almost equivalence (RR 0.95, 95% confidence interval 0.87 to 1.03). Vasopressors used as add‐on therapy in comparison to placebo were not effective either. These findings were consistent among the few large studies as well as in studies with different levels of within‐study bias risk.
Authors' conclusions
There is some evidence of no difference in mortality between norepinephrine and dopamine. Dopamine appeared to increase the risk for arrhythmia. There is not sufficient evidence of any difference between any of the six vasopressors examined. Probably the choice of vasopressors in patients with shock does not influence the outcome, rather than any vasoactive effect per se. There is not sufficient evidence that any one of the investigated vasopressors is clearly superior over others.
PICOs
Plain language summary
Vasopressors for shock
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.
