Severe hypothermia with cardiac arrest: complete neurologic recovery in a 4-year-old child

Optimizing patient selection for ECMO after pediatric hypothermic cardiac arrest

BACKGROUND

In 2004, our level 1 regional pediatric trauma center created a protocol to activate ECMO for children with suspected hypothermic cardiac arrest based on inclusion criteria: serum potassium ≤9, submersion <90 min, and core body temperature <30 °C. In 2017, Pasquier et al. developed a model to help predict the survival of adults after hypothermic cardiac arrest (HOPE score) that has not been validated in children. We sought to apply this score to our pediatric patient population to determine if it can optimize our patient selection.

METHODS

This was a retrospective review of all patients cannulated onto VA ECMO for hypothermic cardiac arrest between 2004 and 2022. We used abstracted data points to calculate the HOPE score for our patient population, both with and without presumed asphyxia.

RESULTS

Over 19 years, 18 patients were cannulated for suspected hypothermic arrest, with three survivors (17 %). The HOPE score survival prediction ranged from 1 to 86 % with presumed asphyxia and 6-98 % without presumed asphyxia. Survivor HOPE scores ranged from 9 to 86 % with presumed asphyxia and 42-98 % without presumed asphyxia. Non-survivors' scores ranged 1-29 % with asphyxia and 6-57 % without asphyxia. A cutoff of >5 % predicted survival with asphyxia for ECMO could have decreased our cannulations by half without missing survivors.

CONCLUSION

ECMO can be a lifesaving measure for specific children after hypothermic arrest. However, identifying the patients that will benefit from this resource-intensive intervention remains difficult. HOPE score utilization may decrease the rate of futile cannulation in children, but multi-centered research is needed in the pediatric population.

On-Site Medical Management of Avalanche Victims-A Narrative Review

Avalanche accidents are common in mountain regions and approximately 100 fatalities are counted in Europe each year. The average mortality rate is about 25% and survival chances are mainly determined by the degree and duration of avalanche burial, the patency of the airway, the presence of an air pocket, snow characteristics, and the severity of traumatic injuries. The most common cause of death in completely buried avalanche victims is asphyxia followed by trauma. Hypothermia accounts for a minority of deaths; however, hypothermic cardiac arrest has a favorable prognosis and prolonged resuscitation and extracorporeal rewarming are indicated. In this article, we give an overview on the pathophysiology and on-site management of avalanche victims.

Wilderness Medical Society Clinical Practice Guidelines for the Out-of-Hospital Evaluation and Treatment of Accidental Hypothermia: 2019 Update

To provide guidance to clinicians, the Wilderness Medical Society convened an expert panel to develop evidence-based guidelines for the out-of-hospital evaluation and treatment of victims of accidental hypothermia. The guidelines present the main diagnostic and therapeutic modalities and provide recommendations for the management of hypothermic patients. The panel graded the recommendations based on the quality of supporting evidence and a balance between benefits and risks/burdens according to the criteria published by the American College of Chest Physicians. The guidelines also provide suggested general approaches to the evaluation and treatment of accidental hypothermia that incorporate specific recommendations. This is the 2019 update of the Wilderness Medical Society Practice Guidelines for the Out-of-Hospital Evaluation and Treatment of Accidental Hypothermia: 2014 Update.

Accidental hypothermia-an update : The content of this review is endorsed by the International Commission for Mountain Emergency Medicine (ICAR MEDCOM)

BACKGROUND

This paper provides an up-to-date review of the management and outcome of accidental hypothermia patients with and without cardiac arrest.

METHODS

The authors reviewed the relevant literature in their specialist field. Summaries were merged, discussed and approved to produce this narrative review.

RESULTS

The hospital use of minimally-invasive rewarming for non-arrested, otherwise healthy, patients with primary hypothermia and stable vital signs has the potential to substantially decrease morbidity and mortality for these patients. Extracorporeal life support (ECLS) has revolutionised the management of hypothermic cardiac arrest, with survival rates approaching 100 % in some cases. Hypothermic patients with risk factors for imminent cardiac arrest (temperature <28 °C, ventricular arrhythmia, systolic blood pressure <90 mmHg), and those who have already arrested, should be transferred directly to an ECLS-centre. Cardiac arrest patients should receive continuous cardiopulmonary resuscitation (CPR) during transfer. If prolonged transport is required or terrain is difficult, mechanical CPR can be helpful. Delayed or intermittent CPR may be appropriate in hypothermic arrest when continuous CPR is impossible. Modern post-resuscitation care should be implemented following hypothermic arrest. Structured protocols should be in place to optimise pre-hospital triage, transport and treatment as well as in-hospital management, including detailed criteria and protocols for the use of ECLS and post-resuscitation care.

CONCLUSIONS

Based on new evidence, additional clinical experience and clearer management guidelines and documentation, the treatment of accidental hypothermia has been refined. ECLS has substantially improved survival and is the treatment of choice in the patient with unstable circulation or cardiac arrest.

An evaluation of the Swiss staging model for hypothermia using case reports from the literature

BACKGROUND

Core body temperature is used to stage and guide the management of hypothermic patients, however obtaining accurate measurements of core temperature is challenging, especially in the pre-hospital context. The Swiss staging model for hypothermia uses clinical indicators to stage hypothermia. The proposed temperature range for clinical stage 1 is <35-32 °C (95-90 °F), for stage 2, <32-28 °C (<90-82 °F) for stage 3, <28-24 °C (<82-75 °F), and for stage 4 below 24 °C (75 °F). However, the evidence relating these temperature ranges to the clinical stages needs to be strengthened.

METHODS

Medline was used to retrieve data on as many cases of accidental hypothermia (core body temperature <35 °C (95 °F)) as possible. Cases of therapeutic or neonatal hypothermia and those with confounders or insufficient data were excluded. To evaluate the Swiss staging model for hypothermia, we estimated the percentage of those patients who were correctly classified and compared the theoretical with the observed ranges of temperatures for each clinical stage. The number of rescue collapses was also recorded.

RESULTS

We analysed 183 cases; the median temperature for the sample was 25.2 °C (IQR 22-28). 95 of the 183 patients (51.9%; 95% CI = 44.7%-59.2%) were correctly classified, while the temperature was overestimated in 36 patients (19.7%; 95% CI = 13.9%-25.4%). We observed important overlaps among the four stage groups with respect to core temperature, the lowest observed temperature being 28.1 °C for Stage 1, 22 °C for Stage 2, 19.3 °C for Stage 3, and 13.7 °C for stage 4.

CONCLUSION

Predicting core body temperature using clinical indicators is a difficult task. Despite the inherent limitations of our study, it increases the strength of the evidence linking the clinical hypothermia stage to core temperature. Decreasing the thresholds of temperatures distinguishing the different stages would allow a reduction in the number of cases where body temperature is overestimated, avoiding some potentially negative consequences for the management of hypothermic patients.

Wilderness Medical Society practice guidelines for the out-of-hospital evaluation and treatment of accidental hypothermia: 2014 update

To provide guidance to clinicians, the Wilderness Medical Society (WMS) convened an expert panel to develop evidence-based guidelines for the out-of-hospital evaluation and treatment of victims of accidental hypothermia. The guidelines present the main diagnostic and therapeutic modalities and provide recommendations for the management of hypothermic patients. The panel graded the recommendations based on the quality of supporting evidence and the balance between benefits and risks/burdens according the criteria published by the American College of Chest Physicians. The guidelines also provide suggested general approaches to the evaluation and treatment of accidental hypothermia that incorporate specific recommendations. This is an updated version of the original Wilderness Medical Society Practice Guidelines for the Out-of-Hospital Evaluation and Treatment of Accidental Hypothermia published in Wilderness & Environmental Medicine 2014;25(4):425-445.

Wilderness Medical Society practice guidelines for the out-of-hospital evaluation and treatment of accidental hypothermia

To provide guidance to clinicians, the Wilderness Medical Society (WMS) convened an expert panel to develop evidence-based guidelines for the out-of-hospital evaluation and treatment of victims of accidental hypothermia. The guidelines present the main diagnostic and therapeutic modalities and provide recommendations for the management of hypothermic patients. The panel graded the recommendations based on the quality of supporting evidence and the balance between benefits and risks/burdens according the criteria published by the American College of Chest Physicians. The guidelines also provide suggested general approaches to the evaluation and treatment of accidental hypothermia that incorporate specific recommendations.

An established extracorporeal membrane oxygenation protocol promotes survival in extreme hypothermia

BACKGROUND

Historical reports indicate that active rewarming with extracorporeal membrane oxygenation (ECMO) can salvage a patient after hypothermic cardiac arrest. We created a protocol that includes ECMO for extreme hypothermia to guide rewarming of the hypothermic patient.

METHODS

A retrospective review of the ECMO rewarming protocol (2004-2006) was conducted.

RESULTS

The active rewarming protocol is a flowchart that is available on our hospital intranet and can be accessed in the trauma bay. A severely hypothermic patient triggers the activation of a TRAUMA ONE-OP ECMO response. During the 2-year period, there were 5 activations of the system and 4 children were placed on ECMO. Two of the 4 were dramatically salvaged and eventually discharged neurologically intact. All 5 children were found pulseless at the scene before transport. The average time from the injury occurrence to arrival was 94 minutes (range, 41-181 minutes). Mean cardiopulmonary resuscitation time was 78.2 minutes (range, 37-152 minutes). The mean core temperature on arrival was 25.4 degrees C (range, 20.4 degrees C-28.6 degrees C). The average time from arrival to ECMO cannulation was 25.5 minutes (range, 16-37 minutes).

CONCLUSION

A preemptive strategy for the severely hypothermic patient provides an organized approach and prompt response. Expeditious rewarming can make the difference in an opportunity for survival.

[Severe accidental hypothermia with cardiac arrest and extracorporeal rewarming. A case report of a 2-year-old child]

In patients with severe hypothermia and cardiac arrest, active rewarming is recommended by extracorporeal circulation with cardiopulmonary bypass. The current guidelines for resuscitation of the European Resuscitation Council now include the recommendation regarding patients with hypothermia remaining comatose after initial resuscitation to accomplish an active rewarming only up to a temperature of 32-34 degrees C and to maintain a mild hypothermia for 12-24 h. We report the case of a 2-year-old boy who suffered from severe hypothermia after falling into ice-cold water. On discovery cardiac arrest with asystole was present and the first measured temperature was 23.8 degrees C. Resuscitation led to restoration of spontaneous circulation. The patient was rewarmed by extracorporeal circulation with cardiopulmonary bypass to 33 degrees C then mild hypothermia was maintained for a further 12 h. On the third day after the accident the patient was extubated and after a further 9 days was discharged without any sequelae.