Dopamine versus norepinephrine: is one better?

Dopamine and norepinephrine are widely used as first line agents to correct hypotension in patients with acute circulatory failure. There has been considerable debate in recent years as to whether one is better than the other. Both drugs can increase blood pressure in shock states, although norepinephrine is more powerful. Dopamine can increase cardiac output more than norepinephrine, and in addition to the increase in global blood flow, has the potential advantage of increasing renal and hepatosplanchnic blood flow. However, dopamine has potentially detrimental effects on the release of pituitary hormones and especially prolactin, although the clinical relevance of these effects is unclear. Observational studies have provided conflicting results regarding the effects of these two drugs on outcomes, and results from a recently completed randomized controlled trial are eagerly waited.