Rhythm Nation April 2015 – Answer!

by eabram • April 20, 2015 • Comments Off

Excellent interpretation by Dr. Tepler!

Exactly right, bradycardia and Osborn waves were concerning for a cold patient – in this case had moderate hypothermia. The Osborn wave (aka J wave) is seen in a variety of conditions. It can be a normal variant, but with the combination of bradycardia other causes (especially hypothermia) should be sought. Osborn waves can also be seen in hypercalcemia, intracranial hemorrhage, and certain tachydysrrhythmias.

Hypothermia is below 95 degrees Fahrenheit or 35 degrees Celsius. Osborn waves tend to be correlated with the severity of hypothermia. They are, however, considered neither prognostic nor pathognomonic for myocardial damage.

Hypothermia patients require rapid rewarming, and are prone to dysrhythmias. Atrial arrhythmias can include atrial fibrillation with slow ventricular response and sinus bradycardia. These are generally considered more benign than the ventricular arrhythmias and rarely necessitate cardiac transthoracic pacing. A cold patient who goes into ventricular fibrillation warrants CPR with one attempt at ventricular defibrillation below 30 degrees Celsius. If ventricular fibrillation continues, continue compressions and active rewarming. Further attempts can be made for every 1-2 degrees Celsius that the patient rewarms. Most cardioactive drugs are less active in the cold patient, which leaves active rewarming the main priority.

References:

Danzl D.F. Danzl, Daniel F.(2015). Hypothermia and Frostbite. In Kasper D, Fauci A, Hauser S, Longo D, Jameson J, Loscalzo J. Kasper D, Fauci A, Hauser S, Longo D, Jameson J, Loscalzo J Eds. Dennis Kasper, et al. (Eds), Harrison’s Principles of Internal Medicine, 19e. Retrieved April 20, 2015 from http://accessmedicine.mhmedical.com.newproxy.downstate.edu/content.aspx?bookid=1130&Sectionid=79757945.

Bessen H.A., Ngo B Bessen, Howard A., and Bryan Ngo.(2011). Chapter 203. Hypothermia. In Tintinalli JE, Stapczynski J, Ma O, Cline DM, Cydulka RK, Meckler GD, T. Tintinalli J.E., Stapczynski J, Ma O, Cline D.M., Cydulka R.K., Meckler G.D., T Eds. Judith E. Tintinalli, et al. (Eds), Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 7e. Retrieved April 20, 2015 from http://accessmedicine.mhmedical.com.newproxy.downstate.edu/content.aspx?bookid=348&Sectionid=40381685.

Supervised by Dr. Jennifer Martindale.

The views expressed on this blog are the author's own and do not reflect the views of their employer. Please read our full disclaimer here. Any references to clinical cases refer to patients treated at a virtual hospital, Janus General Hospital.