Toxic Shock Drug Might Aid Trauma Victims

Norepinephrine added to fluids protects against blood loss, study finds.

By Carolyn Colwell
HealthDay Reporter
Thursday, September 27, 2007; 12:00 AM

Copyright © 2007 ScoutNews, LLC. All rights reserved.

THURSDAY, Sept. 27 (HealthDay News) -- The drug norepinephrine may come to the rescue of trauma victims suffering from heavy blood loss and shock, a French study in rats suggests.

"This is the first scientific study showing the benefits of using norepinephrine in hemorrhagic shock," said study author Dr. Marie-Pierre Poloujadoff, an emergency physician at one of the University of Paris' hospitals.

Uncontrolled bleeding is a "huge problem" for human victims of gunshot wounds, automobile accidents and other traumatic injuries, Poloujadoff said. A steep drop in blood volume can quickly lead to hemorrhagic shock.

Once the victim is in surgery, the surgeon will be able to control the shock. However, "the problem is what to do between the accident and surgery," Poloujadoff said. Long delays can be fatal, she said.

In cases involving major blood loss, physicians try and supply the body with fluids so that the heart will keep pumping and blood pressure won't drop too low, she added. But if there is too much fluid, that can actually speed bleeding, decrease coagulation or dilute the blood so it doesn't adequately carry oxygen to the brain.

To control the balance between getting fluids but not too much, emergency physicians may use "vasoconstrictors" -- drugs that narrow blood vessels. The vasoconstrictor norepinephrine is often used in emergency rooms because it's effective against toxic shock.

The unavailability in France of vassopressin, a vasoconstrictor used in the United States, led to the idea of testing norepinephrine, Poloujadoff said.

The animal study involved four groups of 10 rats. Each group received a different dose of norepinephrine, which was used in rats showing normal blood pressure or low blood pressure. The animals were experimented on while under anesthesia.

The researchers sought to replicate emergency room situations resembling those of human patients who might be cared for after copious bleeding linked to head injury.

At specific doses, norepinephrine combined with standard resuscitation fluids significantly boosted the rats' odds of survival, the French team found.