Tuesday, February 26, 2008

Cocaine and Beta Blockers: A Debate Renewed?

Last month’s Annals of Emergency Medicine contains a controversial retrospective cohort study. The study, out of Jacobi Medical Center, argues that beta blockers used after cocaine use for all comers to medicine ICUs, telemetry and cardiac care units reduce the risk of myocardial infarction.
This flies in the face of decades of practice. Many clinicians avoid using beta blockers in these patients because there is a theoretical risk of reducing myocardial perfusion due to unopposed alpha activation and coronary vasospasm. One accompanying editorial calls both of these premises myths. Freeman and Feldman argue that MIs caused by cocaine have more to do with thrombi than with vasospasm. Also, they argue against the supposed “unopposed alpha effect” by saying that beta blockade has proven to be helpful in other patients with endogenous catecholamine release (patients with CHF or subarachnoid hemorrhage, perioperative patients, and trauma patients).

Another accompanying editorial by NYU’s Robert Hoffman calls for attention to the history of this controversy. He says, “when the lack of benefit is weighed against any real or perceived risk, the preponderance of evidence continues to speak against the use of beta-adrenergic antagonists in this setting.” He goes on to call the possibility of prospective studies on this issue “dangerous” because, for an unpredictable subset of cocaine users, the interaction with beta-blockade has proven to be fatal. With all that said, my question as a student is this: is anyone’s current practice going to be altered by any of the evidence presented? I doubt that this is the case but I’d appreciate any responses.

Nick Gavin is a third year medical student at NYU School of Medicine who is interested in emergency medicine and the sociology of health care.

1 comment:

Anonymous said...

my question is at what point after cva 2/2 cocaine would beta blocker be considered safe? assuming the patient is compliant with not using cocaine... probably not but benefit of doubt.