Neth Heart J
H. Lameijer 0
M. Kwant 0
M. Doff-Holman 0
0 Department of Emergency Medicine, University Medical Centre Groningen, University of Groningen , Groningen , The Netherlands
The electrocardiogram of the question shows prolonged
QRS and QTc segments. These symptoms can be seen
in several types of intoxication, including poisoning by
sodium-channel blockers such as tricyclic antidepressants
and cocaine, but not in opioid intoxications. Therefore,
a combined intoxication could be assumed. However, the
most prominent abnormality in this electrocardiogram is
the presence of J waves, best observed in the precordial
leads. The J waves are known as Osborn waves, and are
observed in hypothermia, hypercalcaemia, or Brugada
]. Osborn waves are thought to be caused by
differences in action potential characteristics between the
epicardial and endocardial layers of the heart .
Our patient’s core temperature was 31.8 degrees
Celsius, which classifies as moderate hypothermia. Most
serious complications, such as hypotension or ventricular
fibrillation, occur below 28 degrees Celsius [
whenever electrocardiogram changes are observed, patients are
at risk of life-threatening cardiac rhythm disturbances
irrespective of the severity of hypothermia [
caution is needed. Furthermore, patients should be rewarmed.
Rewarming can be obtained by passive rewarming, such as
hot blankets/air blankets, or active rewarming, such as warm
intravenous fluids therapy, warm bladder or gastric rinses,
or even warm extracorporeal membrane oxygenation.
Our patient was treated with warm intravenous fluids and
hot air blankets. He was transmitted to the intensive care
unit for further observation. A toxicology screening showed
an opioid intoxication with methadone, no other
intoxication was observed. After rewarming, his electrocardiogram
normalised, as observed in Figs. 1 and 2.
Conflict of interest H. Lameijer, M. Kwant and M. Doff-Holman
declare that they have no competing interests.
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Electrocardiogram made during rewarming while the patient is still sedated and intubated. Minor J-point abnormalities are still present
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3. Danzl DF , Pozos RS . Accidental hypothermia . N Engl J Med . 1994 ; 331 : 1756 - 60 .