In an effort to prove the capability of two vasopressor agents in treating shock, doctors conducted a study comparing the ability of dopamine and norepinephrine in restoring stable blood pressure.
Often used to treat shock, vasopressors are agents (most often hormones) that raise the blood pressure of given blood vessels. In this case, the arteriole veins are the most in need during a time of bodily shock because of their deflated ability to pass along oxygenated blood to capillaries that thus oxygenate the body’s tissue and organ systems.
Historically, dopamine is equated to elevated or overused dopamine receptors- most commonly attributed to drug use and addiction. In this case, dopamine triggers a necessary neurological response in the brain, to increase blood pressure in the arteriole veins. Similarly, norepinephrine (often known as noradrenaline) is very helpful in the treatment of shock. Its responses are most often referenced to the fight or flight response, in which noradrenaline spikes blood pressure to expedite reactions in the body to either fight, or fly.
Although the study noted both hormones’ ability to expedite the transfer of oxygenated blood into the capillaries, by alleviating the depressed arteriole veins, their final results were nearly even. “There was no significant between-group difference in the rate of death at 28 days,” the study reported. Yet, “there were more arrhythmic events among the patients treated with dopamine than among those treated with norepinephrine.”
Overall, scientists concluded norepinephrine as the hormone with the least amount of adverse effects. Despite their equal abilities in alleviating low blood pressure and decreased oxygenated organs, events following the use of dopamine negated the progress made to cure the initial low blood pressure.
Sources:
The study was published on March 4, 2010 in the New England Journal of Medicine.
http://content.nejm.org/cgi/content/short/362/9/779