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Osborn wave......


The Osborn wave1 (J wave)  usually appears in hypothermia, disappears after normalization of the body temperature, and is usually evident in the inferolateral leads.

Although Osborn waves are a marker of hypothermia, they also occur in nonhypothermic conditions. Brainstem death is a precursor of the J wave, and this is explained by impaired thermoregulatory ability resulting from hypothalamic dysfunction and subsequent hypoth

  Classic findings in hypothermia include J waves, sinus bradycardia, prolongation of the PR interval, widening of the QRS complex, and prolongation of the QT interval.

The lower the core body temperature, the higher the amplitude of the J wave.

As hypothermia becomes more profound, the J wave becomes evident in all leads, not only the inferolateral leads.

1.    Osborn , Experimental hypothermia; respiratory and blood pH changes in relation to cardiac function. Am J Physiol 1953; 175:389–398. 

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