LAUSR

Whilst lecturing on severe accidental hypothermia (core temperature< 28 °C) to paramedics and prehospital and hospital doctors, we have observed that many are unfamiliar with the special requirements of hypothermic cardiac arrest and would manage this incorrectly by extrapolating the management of normothermic cardiac arrest to the hypothermic situation. The implications of this are significant. For example, it is likely that cardiopulmonary resuscitation (CPR) would be instituted prematurely based on a misinterpretation of clinical signs such as slow respiratory rate and profound bradycardia that are typical in severe hypothermia but do not indicate that cardiac arrest has occurred. Indeed, there are many case reports demonstrating that patients can be successfully rewarmed without CPR despite these ‘abnormal’ features, whereas premature CPR will cause a cardiac arrest that will only terminate when the patient has been rewarmed – something that is much more difficult in the arrested patient. We have compiled a table that compares the two arrest situations to highlight the differences and draw attention to the different management requirements. In our view, the situation is analogous to diabetes (mellitus and insipidus) in which the common feature is polyuria but the underlying cause, management and prognosis are very different (Table 1).