Surviving an out-of-hospital hypothermic cardiac arrest in the United Kingdom.

Introduction: Hypothermia is an uncommon cause of cardiac arrest in the United Kingdom, and more commonly occurs in countries experiencing avalanches and significant winter climates; however, this case demonstrates that the presentation can occur in the United Kingdom. This case adds to a body of evidence that prolonged resuscitation can be successful in patients suffering a cardiac arrest secondary to hypothermia, leading to a good neurological outcome.

Case presentation: The patient suffered a witnessed out-of-hospital cardiac arrest following rescue from a free-flowing river, and underwent prolonged resuscitation. The patient presented in persistent ventricular fibrillation, unresponsive to defibrillation attempts. An oesophageal probe recorded the patient's temperature as 24°C. Rescuers were guided by the Resuscitation Council UK advanced life support algorithm to withhold drug therapy and limit defibrillation attempts to three, until the patient had been rewarmed to above 30°C. Appropriate triage of the patient to an extracorporeal life support (ECLS) capable centre allowed specialised treatment to be initiated, and culminated in successful resuscitation once normothermia was restored. After a short stay in intensive care, the patient was discharged for rehabilitation due to a hypoxic spinal cord injury before discharge home.

Conclusion: This case highlights that hypothermia is a reversible cause of cardiac arrest, which needs to be recognised and acted upon appropriately to provide the best possible chance for a positive outcome. Low-reading thermometers capable of identifying the temperature thresholds stated in the Resuscitation Council UK guidelines are required, to allow clinicians to adapt their practice according to the presenting situation. Tympanic thermometers are often limited to their lowest recordable temperature, and invasive monitoring such as oesophageal or rectal probes are not common in UK ambulance service practice. With the necessary equipment, patients can be triaged to an ECLS-capable centre, allowing them to receive the specialist rewarming that they require.