Severe Accidental Hypothermia Research Articles

Prolonged critical avalanche burial for nearly 23 h with severe hypothermia and severe frostbite with good recovery: a case report

BackgroundAccidental hypothermia with severe frostbite is a rare combination of injuries with a high risk for long-term sequelae. There are widely accepted recommendations for the management of avalanche victims and for frostbite treatment, but no recommendation exists for the treatment of frostbite in severe hypothermic patients, specifically for the management of hypothermic avalanche victims presenting with frostbite.Case presentationWe present a case of a previously healthy, 53-year-old male skier who was critically buried by an avalanche at 2300 m of altitude at an ambient temperature of − 8 °C for nearly 23 h. The victim was found with the right hand out of the snow and an air connection to outside. He was somnolent with Glasgow Coma Scale 11 (Eye 4, Verbal 2, Motor 5) and spontaneously breathing, in a severely hypothermic state with an initial core temperature of 23.1 °C and signs of cold injuries in all four extremities. After rescue and active external forced air rewarming in the intensive care unit, the clinical signs of first-degree frostbite on both feet and the left hand vanished, while third- to fourth-degree frostbite injuries became apparent on all fingers of the right hand. After reaching a core body temperature of approximately 36 °C, aggressive frostbite treatment was started with peripheral arterial catheter-directed thrombolysis with alteplase, intravenous iloprost, ibuprofen, dexamethasone and regional sympathicolysis with a right-sided continuous axillary block. After ten months, the patient had no tissue loss but needed neuropathic pain treatment with pregabalin.ConclusionThe combination of severe accidental hypothermia and severe frostbite is rare and challenging, as drug metabolism is unpredictable in a hypothermic patient and no recommendations for combined treatment exist. There is general agreement to give hypothermia treatment the priority and to begin frostbite treatment as early as possible after full rewarming of the patient. More evidence is needed to identify the optimal dosage and time point to initiate treatment of frostbite in severely hypothermic patients. This should be taken into consideration by future treatment recommendations.

Predictors of cardiac arrest in severe accidental hypothermia

Study objectiveTo indicate predictors of witnessed hypothermic cardiac arrest. MethodsWe conducted a retrospective analysis of 182 patients with severe accidental hypothermia (i.e., with core body temperature of ≤28 °C) who presented with preserved spontaneous circulation at first contact with medical services. We divided the study population into two groups: patients who suffered hypothermic cardiac arrest (HCA) at any time between encounter with medical service and restoration of normothermia, and those who did not sustain HCA. The analyzed outcome was the occurrence of cardiac arrest prior to achieving normothermia. Hemodynamic and biochemical parameters were analyzed with regard to their association with the outcome. ResultsFifty-two (29%) patients suffered HCA. In a univariable analysis, four variables were significantly associated with the outcome, namely heart rate (p < 0.001), systolic blood pressure (p = 0.03), ventricular arrhythmia (p = 0.001), and arterial oxygen partial pressure (p = 0.002). In the multivariable logistic regression the best model predicting HCA included heart rate, PaO2, and Base Excess (AUROC = 0.78). In prehospital settings, when blood gas analysis is not available, other multivariable model including heart rate and occurrence of ventricular arrhythmia (AUROC = 0.74) can be used. In this study population, threshold values of heart rate of 43/min, temperature-corrected PaO2 of 72 mmHg, and uncorrected PaO2 of 109 mmHg, presented satisfactory sensitivity and specificity for HCA prediction. ConclusionsIn patients with severe accidental hypothermia, the occurrence of HCA is associated with a lower heart rate, hypoxemia, ventricular arrhythmia, lower BE, and lower blood pressure. These parameters can be helpful in the early selection of high-risk patients and their allocation to extracorporeal rewarming facilities.

Outcome of extracorporeal membrane oxygenation use in severe accidental hypothermia with cardiac arrest and circulatory instability: A multicentre, prospective, observational study in Japan (ICE-CRASH study)

AimTo elucidate the effectiveness of extracorporeal membrane oxygenation (ECMO) in accidental hypothermia (AH) patients with and without cardiac arrest (CA), including details of complications. MethodsThis study was a multicentre, prospective, observational study of AH in Japan. All adult (aged ≥18 years) AH patients with body temperature ≤32 °C who presented to the emergency department between December 2019 and March 2022 were included. Among the patients, those with CA or circulatory instability, defined as severe AH, were selected and divided into the ECMO and non-ECMO groups. We compared 28-day survival and favourable neurological outcomes at discharge between the ECMO and non-ECMO groups by adjusting for the patients’ background characteristics using multivariable logistic regression analysis. ResultsAmong the 499 patients in this study, 242 patients with severe AH were included in the analysis: 41 in the ECMO group and 201 in the non-ECMO group. Multivariable analysis showed that the ECMO group was significantly associated with better 28-day survival and favourable neurological outcomes at discharge in patients with CA compared to the non-ECMO group (odds ratio [OR] 0.17, 95% confidence interval [CI]: 0.05–0.58, and OR 0.22, 95%CI: 0.06–0.81). However, in patients without CA, ECMO not only did not improve 28-day survival and neurological outcomes, but also decreased the number of event-free days (ICU-, ventilator-, and catecholamine administration-free days) and increased the frequency of bleeding complications. ConclusionsECMO improved survival and neurological outcomes in AH patients with CA, but not in AH patients without CA.

Спосіб інтенсивної терапії загального переохолодження

Актуальність. Загальне переохолодження є однією з найбільш складних проблем сучасної інтенсивної терапії критичних станів. Метою роботи були вивчення ефективності розробленого способу інтенсивної терапії загального переохолодження, оцінка його впливу на швидкість корекції патофізіологічних зрушень і рівень летальності пацієнтів у критичному або термінальному стані. Матеріали та методи. Обстежено 50 пацієнтів (середній вік — 43,00 ± 3,62 року), стан яких був оцінений відповідно до класифікації стадій загального переохолодження Швейцарського товариства гірської медицини. Пацієнти були розподілені на 2 групи: I група (n = 25) — з активним зігріванням системою конвекційного обігріву Warm Air 135 (CSZ, США) та інфузією 37 °С кристалоїдних розчинів у таких дозах: при легкому ступені — 20–30 мл/кг; помірного та тяжкого ступеня — 50–70 мл/кг, із включенням колоїдних розчинів. II група (n = 25) — із пасивним зігріванням і стандартним комплексом інтенсивної терапії, що включав інфузію кристалоїдних і колоїдних розчинів кімнатної температури в дозі 20–30 мл/кг. Вивчалися езофагальна і тімпанітна температури, показники гемодинаміки (артеріальний тиск, частота серцевих скорочень, середній артеріальний тиск), ступінь неврологічного дефіциту за шкалою коми Глазго, швидкість зігрівання. Результати. Вихідна температура ядра тіла у I групі становила 29,03 ± 2,76 °С, у II групі — 31,50 ± 1,97 °С. Мінімальне та максимальне значення температури ядра тіла в I групі становили 24,3 і 33,6 °С; у II — 27,2 і 34,5 °С відповідно. Початковий рівень середнього артеріального тиску становив у I групі 49,86 ± 20,71 мм рт.ст., у II — 70,45 ± 11,72 мм рт.ст.; через 48 годин — 76,65 ± 12,27 мм рт.ст. та 60,82 ± 36,39 мм рт.ст. відповідно. Швидкість досягнення нормотермії (36,0 °С) у I і II групах становила 6,48 ± 3,47 години та 9,20 ± 6,52 години відповідно. Рівень летальності в I групі — 12 %, у II — 48 %, указані відмінності були вірогідними. Висновки. Використання вказаного вище способу інтенсивної терапії загального переохолодження дозволяє знизити летальність на 25 %.

CASE SERIES OF SEVERE ACCIDENTAL HYPOTHERMIC CARDIAC ARREST TREATED SUCCESSFULLY WITH CARDIOPULMONARY BYPASS IN A UNIVERSITY HOSPITAL IN UNITED KINGDOM

Introduction Accidental hypothermia is unintentional decrease in body temperature below 35°C. Severe hypothermia is when temperature drops below 28°C and have a high mortality rate. Methods Case 1 A 48 year old man suspected CVA fall into freezing canal. He was clinging on the side of canal. He developed cardiac arrest when retrieved by crew. Three unsuccessful shocks administered. His temperature was 21° C in ED. A midline sternotomy performed and CPB achieved. He was slowly rewarmed and acidosis corrected. When temperature was 27.5° C,internal DC Cardioversion delivered, reverted him to sinus rhythm. He was successfully weaned of CPB. Total CPB time was 4 hours and 38 min. The patient was extubated next day. He had mild dysarthria and expressive dysphasia. He was discharged to stoke unit on day 3 and improved after stroke rehabilitation. Case 2 A 53 year old female, with previous history of mental illness, found unresponsive adjacent to reservoir, with weighted bag and ankles tied with chains and padlocks. She had cardiac arrest and temperature recorded as 14.1°C. She was airlifted to ED. Initial ABG pH 7.23, Lactate 2.5 and K of 4.0. No shockable rhythm achieved. She was profoundly coagulopathic with INR>10, APTT ratio>5 and Fibrinogen level A femoro-femoral bypass was done. She was slowly rewarmed, coagulopathy and acidosis corrected. She was severely vasoplegic and developed pulmonary oedema. At temperature of 28°C, developed sinus rhythm. She was successfully weaned off CPB after six hours with high doses of vasopressors. She developed TRALI and was ventilated for 12 days. She was confused, withdrawn and non-engaging with staff, with no focal neurological signs and a normal EEG. She received mental health support and rehabilitation and was discharged to a mental health unit on day 30. Results Severe accidental hypothermia is associated with high mortality rate ranging from 30-80% [1]. The neurological outcomes of the survivors are usually good, when the reason for cardiac arrest is not asphyxia. There are retrospective observational studies suggesting prognostic indicators which may predict survival on admission to hospital. Hyperkalemia, pH 400, increased ammonia levels and raised PaCO2 are bad prognostic indicators. A study by Eich et al showed that early initiation of basic life support, hypokalemia, female gender and slow rewarming to be indicators of superior outcomes. CPB is recommended for hypothermic patients in arrest and for patients with core temperatures lower than 25°C. CPB and ECMO has encouraging survival rate of unto 63%. CPB ensures controlled gradual increase in core body temperature and adequate tissue oxygenation. Discussion This case series demonstrates successful recovery with good neurological outcome from severe accidental hypothermic cardiac arrest with CPB in our institution over one year period. For severe hypothermia, CPB is extremely useful treatment device. The prognostic indicators are unclear and more evidence is required.

Hypothermic Cardiac Arrest – Retrospective cohort study from the International Hypothermia Registry

AimThe International Hypothermia Registry (IHR) was created to increase knowledge of accidental hypothermia, particularly to develop evidence-based guidelines and find reliable outcome predictors. The present study compares hypothermic patients with and without cardiac arrest included in the IHR. MethodsDemographic, pre-hospital and in-hospital data, method of rewarming and outcome data were collected anonymously in the IHR between 2010 and 2020. ResultsTwo hundred and one non-consecutive cases were included. The major causeof hypothermia was mountain accidents, predominantly in young men. Hypothermic Cardiac Arrest (HCA) occurred in 73 of 201 patients. Core temperature was significantly lower in the patients in cardiac arrest (25.0 vs. 30.0 °C, p < 0.001). One hundred and fifteen patients were rewarmed externally (93% with ROSC), 53 by extra-corporeal life support (ECLS) (40% with ROSC) and 21 with invasive internal techniques (71% with ROSC). The overall survival rate was 95% for patients with preserved circulation and 36% for those in cardiac arrest. Witnessed cardiac arrest and ROSC before rewarming were positive outcome predictors, asphyxia, coagulopathy, high potassium and lactate negative outcome predictors. ConclusionsThis first analysis of 201 IHR patients with moderate to severe accidental hypothermia shows an excellent 95% survival rate for patients with preserved circulation and 36% for HCA patients. Witnessed cardiac arrest, restoration of spontaneous circulation, low potassium and lactate and absence of asphyxia were positive survival predictors despite hypothermia in young, healthy adults after mountaineering accidents. However, accidental hypothermia is a heterogenous entity that should be considered in both treatment strategies and prognostication.

The efficiency of continuous renal replacement therapy for rewarming of patients in accidental hypothermia--An experimental study.

Severe accidental hypothermia carries high mortality and morbidity and is often treated with invasive extracorporeal methods. Continuous veno-venous hemodiafiltration (CVVHDF) is widely available in intensive care units. We sought to provide theoretical basis for CVVHDF use in rewarming of hypothermic patients. CVVHDF system was used in the laboratory setting. Heat balance and transferred heat units were evaluated for the system without using blood. We used 5L of crystalloid solution at the temperature of approximately 25°C, placed in a thermally insulated tank (representing the "central compartment" of a hypothermic patient). Time of warming the central compartment from 24.9 to 30.0°C was assessed with different flow combinations: "blood" (central compartment fluid) 50 or 100 or 150mL/min, dialysate solution 100 or 1500mL/h, and substitution fluid 0 or 500mL/h. The total circulation time was 1535minutes. There were no differences between heat gain values on the filter depending on blood flow (P=.53) or dialysate flow (P=.2). The mean heating time for "blood" flow rates 50, 100, and 150mL/min was 113.7minutes (95% CI, 104.9-122.6minutes), 83.3minutes (95% CI, 76.2-90.3minutes), and 74.7minutes (95% CI, 62.6-86.9minutes), respectively (P<.01). The respective median rewarming rate for different "blood" flows was 3.6°C/h (IQR, 3.0-4.2°C/h), 4.8 (IQR, 4.2-5.4°C/h), and 5.4 (IQR, 4.8-6.0°C/h), respectively (P<.01). The dialysate flow did not affect the warming rate. Based on our experimental model, CVVHDF may be used for extracorporeal rewarming, with the rewarming rates increasing achieved with higher blood flow rates.

Bradycardia in a newborn with accidental severe hypothermia: treat or don\u2019t touch?\xa0A case report

BackgroundHypothermia significantly affects mortality and morbidity of newborns. Literature about severe accidental hypothermia in neonates is limited. We report a case of a neonate suffering from severe accidental hypothermia. An understanding of the physiology of neonatal thermoregulation and hypothermia is important to decide on treatment.Case presentationA low-birth-weight newborn was found with severe accidental hypothermia (rectal temperature 25.7 °C) due to prolonged exposure to low ambient temperature. The newborn presented bradycardic, bradypnoeic, lethargic, pale and cold. Bradycardia, bradypnea and impaired consciousness were interpreted in the context of the measured body temperature. Therefore, no reanimation or intubation was initiated. The newborn was closely monitored and successfully treated only with active and passive rewarming.ConclusionClinical parameters such as heart frequency, blood pressure, respiration and consciousness must be interpreted in light of the measured body temperature. Medical treatment should be adapted to the clinical presentation. External rewarming can be a safe and effective measure in neonatal patients.

Impact of rescue collapse on mortality rate in severe accidental hypothermia: A matched-pair analysis

AimTo assess the impact of the occurrence of cardiac arrest associated with initial management on the outcome of severely hypothermic patients who were rewarmed with Extracorporeal Life Support (ECLS). MethodsWe collected the individual data of patients in a state of severe accidental hypothermia who were found with spontaneous circulation and rewarmed with ECLS, from cardiac surgery departments. Patients were divided into two groups: those with a subsequent cardiac arrest (RC group); and those with the retained circulation (HT3 group), and compared by using a matched-pair analysis. The mortality rates and the neurological status in survivors were compared as the main outcomes. The difference in the risk of death between the HT3 and RC groups was calculated. ResultsA total of 124 patients were included into the study: 45 in the HT3 group and 79 in the RC group. The matched cohorts consisted of 45 HT3 patients and 45 RC patients. The mortality rate in both groups was 24% and 49% (p = 0.02) respectively; the relative risk of death was 2.0 (p = 0.02). ICU length of stay was significantly longer in the RC group (p < 0.001). Factors associated with survival in the HT3 group included patient age, rewarming rate, and blood BE; while in the RC group, patient age and lactate concentration. ConclusionsThe occurrence of rescue collapse is linked to a doubling of the risk of death in severely hypothermic patients. Procedures which are known as potential triggers of rescue collapse should be performed with special attention, including in conscious patients.

Maintaining intravenous volume mitigates hypothermia-induced myocardial dysfunction and accumulation of intracellular Ca2.

What is the central question of this study? Detailed guidelines for volume replacement to counteract hypothermia-induced intravascular fluid loss are lacking. Evidence suggests colloids might have beneficial effects compared to crystalloids. Are central haemodynamic function and level of hypothermia-induced calcium overload, as a marker of cardiac injury, restored by fluid substitution during rewarming, and are colloids favourable to crystalloids? What is the main finding and its importance? Infusion with crystalloid or dextran during rewarming abolished post-hypothermic cardiac dysfunction, and partially mitigated myocardial calcium overload. The effects of volume replacement to support haemodynamic function are comparable to those using potent cardio-active drugs. These findings underline the importance of applying intravascular volume replacement to maintain euvolaemia during rewarming. Previous research exploring pathophysiological mechanisms underlying circulatory collapse after rewarming victims of severe accidental hypothermia has documented post-hypothermic cardiac dysfunction and hypothermia-induced elevation of intracellular Ca2+ concentration ([Ca2+ ]i ) in myocardial cells. The aim of the present study was to examine if maintaining euvolaemia during rewarming mitigates cardiac dysfunction and/or normalizes elevated myocardial [Ca2+ ]i . A total of 21 male Wistar rats (300g) were surface cooled to 15°C, then maintained at 15°C for 4h, and subsequently rewarmed to 37°C. The rats were randomly assigned to one of three groups: (1) non-intervention control (n=7), (2) dextran treated (i.v. 12ml/kg dextran 70; n=7), or (3) crystalloid treated (24ml/kg 0.9% i.v. saline; n=7). Infusions occurred during the first 30min of rewarming. Arterial blood pressure, stroke volume (SV), cardiac output (CO), contractility (dP/dtmax ) and blood gas changes were measured. Post-hypothermic changes in [Ca2+ ]i were measured using the method of radiolabelled Ca2+ (45 Ca2+ ). Untreated controls displayed post-hypothermic cardiac dysfunction with significantly reduced CO, SV and dP/dtmax . In contrast, rats receiving crystalloid or dextran treatment showed a return to pre-hypothermic control levels of CO and SV after rewarming, with the dextran group displaying significantly better amelioration of post-hypothermic cardiac dysfunction than the crystalloid group. Compared to the post-hypothermic increase in myocardial [Ca2+ ]i in non-treated controls, [Ca2+ ]i values with crystalloid and dextran did not increase to the same extent after rewarming. Volume replacement with crystalloid or dextran during rewarming abolishes post-hypothermic cardiac dysfunction, and partially mitigates the hypothermia-induced elevation of [Ca2+ ]i .

The use of minimal invasive extracorporeal circulation for rewarming after accidental hypothermia and circulatory arrest.

Extracorporeal cardiopulmonary resuscitation has become a recommended treatment option for patients with severe hypothermia with cardiac arrest. Minimal invasive extracorporeal circulation (MiECC) may offer advantages over the current standard extracorporeal membrane oxygenation (ECMO). Retrospective cohort analysis of hospital database for patients with accidental hypothermia and extracorporeal rewarming with MiECC admitted between 2010 and 2019. Overall, six of 17 patients survived to hospital discharge. Eleven patients suffered accidental hypothermia in an alpine and six in an urban setting. Sixteen patients arrived at the hospital under ongoing cardiopulmonary resuscitation (CPR). CPR time was 90minutes (0-150). Four patients survived from an alpine setting and two from an urban setting with CPR duration of 90minutes (0-150) and 85minutes (25-100), respectively. Asphyctic patients tended to have lower survival (one of seven patients). Two patients of six with major trauma survived. MiECC for extracorporeal rewarming from severe accidental hypothermia is a feasible alternative to ECMO, with comparable survival rates.

Cardiac arrest caused by accidental severe hypothermia and myocardial infarction during general anesthesia

Therapeutic hypothermia is often used for traumatic brain injury because of its neuroprotective effect and decreased secondary brain injury. However, this procedure lacks clinical evidence supporting its efficacy, and adverse outcomes have been reported during general anesthesia. A 61-year-old man with a history of percutaneous coronary intervention (PCI) was admitted with traumatic brain injury. Immediately after admission, he underwent mild therapeutic hypothermia with a target temperature of 33.0°C for neuroprotection. During general anesthesia for emergency surgery because he developed a mass effect, hypothermic cardiac arrest occurred following an additional decrease in the core body temperature. Moreover, myocardial infarction caused by restenosis of the previous PCI lesion also contributed to the cardiac arrest. Although the patient recovered spontaneous circulation after an hour-long cardiopulmonary resuscitation with rewarming, he eventually died of subsequent repetitive cardiac arrests. When anesthetizing patients undergoing therapeutic hypothermia, caution is required to prevent adverse outcomes that can be caused by unintentional severe hypothermia and exacerbation of underlying heart disease.

Accidental hypothermia: characteristics, outcomes, and prognostic factors-A nationwide observational study in Japan (Hypothermia study 2018 and 2019).

AimThis study describes the clinical characteristics and outcomes as well as the prognostic factors of patients with accidental hypothermia (AH) using Japan’s nationwide registry data.MethodsThe Hypothermia study 2018 and 2019, which included patients aged 18 years or older with a body temperature of 35°C or less, was a multicenter registry conducted at 87 and 89 institutions throughout Japan, with data collected from December 2018 to February 2019 and December 2019 to February 2020, respectively.ResultsIn total, 1363 patients were enrolled in the registry, of which 1194 were analyzed in this study. The median (interquartile range) age was 79 (68–87) years, and the median (interquartile range) body temperature at the emergency department was 30.8°C (28.4–33.6°C). Forty‐three percent of patients with AH had a mild condition, 35.2% moderate, and 21.9% severe. AH occurred in an indoor setting in 73.4% and was caused by acute medical illness in 49.3% of patients. A total of 101 (8.5%) patients suffered from cardiopulmonary arrest on arrival at the hospital. The overall 30‐day mortality rate was 24.5%, the median (interquartile range) intensive care unit stay was 4 (2–7) days, and the median (interquartile range) hospital stay was 13 (4–27) days. In the multivariable logistic analysis, the prognostic factors were age (≥75 years old), male, activities of daily living (needing total assistance), cause of AH (trauma, alcohol), Glasgow Coma Scale score, and potassium level (>5.5 mEq/L).ConclusionThe mortality rate of AH was 24.5% in Japan. The prognostic factors developed in this study may be useful for the early prediction, prevention, and awareness of severe AH.

Extracorporeal life support rewarming rate is associated with survival with good neurological outcome in accidental hypothermia.

Favourable outcomes have been demonstrated after extracorporeal life support (ECLS) facilitated rewarming for severe accidental hypothermia. The clinical impact of varying rewarming rates however is unclear. We sought to quantify the change in the probability of good neurological outcome with ECLS rewarming rate and identify the optimal rewarming rate threshold. We performed a secondary analysis of the International ACcidental Hypothermia Extracorporeal Life Support Collaborators, an individual patient data data set (n = 658) for ECLS-assisted rewarming for accidental hypothermia. The independent variable of interest was rewarming rate. The primary outcome was survival with good neurological status. We applied an adjusted marginal effects model to quantify the probability of good neurological outcome over clinically observed rewarming rates. We examined strata defined by sex, initial potassium level and history of asphyxiation. Of 658 cases, the median age and initial core temperature were 36 years (22-55) and 24.5°C (22.1-26.2) respectively; 190 (29%) were female, and 547 (83%) had a non-perfusing initial cardiac rhythm. The mean rewarming rate was 7.0°C/h. The median ECLS duration was 5.8 h (range: 0.5-158 h). The overall survival was 46% (n = 303/658), and good neurological outcome was 40% (n = 265/658). The median intensive care unit and hospital length of stay was 5 days (range: 1-35 days) and 18 days (range: 1-106 days), respectively. Marginal effects analysis demonstrated a 1.9% decrease in the probability of survival with good neurological outcome for each 1°C/h increase in rewarming. Across the reported range of rewarming rates (0.05-30.8°C/h), the probability of good neurological outcome declined from 49.6% to 4.1% for an average patient. The relationship was similar within various subgroups. The optimal cut-off threshold for the rate of rewarming to distinguish between a good and poor neurological outcome was ≤5.0°C/h. Among cases with severe accidental hypothermia treated with ECLS, slower rewarming rates are associated with improved survival with good neurological outcomes. Slow rewarming, at rates ≤5.0°C/h, may improve clinical outcomes.

Severe Accidental Hypothermia Managed with Continuous Venovenous Hemofiltration

Severe Accidental Hypothermia Managed with Continuous Venovenous Hemofiltration

Successful resuscitation from prolonged hypothermic cardiac arrest without extracorporeal life support: a case report

BackgroundWe report a case of successful prolonged cardiopulmonary resuscitation (5 hours and 44 minutes) following severe accidental hypothermia with cardiac arrest treated without rewarming on extracorporeal life support.Case presentationA 52-year-old Italian mountaineer, was trapped in a crevasse and rescued approximately 7 hours later by a professional rescue team. After extrication, he suffered a witnessed cardiac arrest with ventricular fibrillation. Immediate defibrillation and cardiopulmonary resuscitation were started. His core temperature was 26.0 °C. Due to weather conditions, air transport to an extracorporeal life support center was not possible. Thus, he was rewarmed with conventional rewarming methods in a rural hospital. Auto-defibrillation occurred at a core temperature of 29.8 °C after 5 hours and 44 minutes of continued cardiopulmonary resuscitation. With a core temperature of 33.4 °C, he was finally admitted to a level 1 trauma center and extracorporeal life support was no longer required. Seven weeks following the accident, he was discharged home with complete neurological recovery.ConclusionsSuccessful rewarming from severe hypothermia without extracorporeal life support use as performed in this case suggests that patients with primary hypothermic cardiac arrest have a chance of a favorable neurological outcome even after several hours of cardiac arrest when cardiopulmonary resuscitation and conventional rewarming are performed continuously. This may be especially relevant in remote areas, where extracorporeal life support rewarming is not available.

Complete Neurological Recovery after Severe Accidental Hypothermia: Two Cases and a Novel Algorithm Proposal

Primary accidental hypothermia results from endogenous thermoregulatory mechanisms being overwhelmed by environmental stressors. Vulnerable populations include the elderly, mentally ill, homeless, and chemically dependent. When core temperatures fall below 35°C, the resulting metabolic derangements provoke cardiopulmonary compromise and dysrhythmia. Due to the human body’s innate protective mechanisms there are reports of patients making complete neurologic recovery after exposure to extreme temperatures and prolonged cardiopulmonary arrest. We describe two cases from our institution demonstrating appropriate treatment methods for the two most severe stages of hypothermia. A 57-year-old male with a core temperature of 27°C who was successfully resuscitated with warm bladder and thoracic lavage and a 34-year-old female with a core temperature of 22°C that fully recovered after 5 hours of external cardiopulmonary bypass. From our experience and a review of the literature, we have developed a modified version of the Swiss staging model and incorporated it into a novel treatment algorithm for in-hospital adult accidental hypothermia patients presenting to urban community hospitals. The two example cases described highlight how appropriate utilization of this novel algorithm can lead to positive outcomes in otherwise critical clinical scenarios.

Management of accidental hypothermia: an established extracorporeal membrane oxygenation centre experience.

Data on management of severe accidental hypothermia published from an established high-volume extracorporeal membrane oxygenation centre are scarce. A total of 28 patients with intravesical temperature lower than 28°C on admission were either treated with veno-arterial extracorporeal membrane oxygenation or rewarmed conservatively. A total of 10 patients rewarmed on veno-arterial extracorporeal membrane oxygenation (age: 37 ± 12.6 years) and 18 conservatively (age: 55.2 ± 11.2 years) were collected over a course of 5 years. The dominant cause was alcohol intoxication with exposure to cold (39%), 12 patients were resuscitated prior to admission. The admission temperature in the extracorporeal membrane oxygenation group (23.8 ± 2.6°C) was lower than in the non-extracorporeal membrane oxygenation group (26.0 ± 1.5°C, p = 0.01). The peripheral percutaneous veno-arterial extracorporeal membrane oxygenation was always cannulated in malignant arrhythmias causing refractory cardiac arrest. The typical extracorporeal membrane oxygenation blood flow was 3-4 L/minute and sweep gas flow 2 L/minute, the median extracorporeal membrane oxygenation duration was 48.3 (28.1-86.7) hours. The median rates of rewarming did not differ (0.41 (0.35-0.7)°C/hour in extracorporeal membrane oxygenation and 0.77 (0.54-0.98)°C/hour in non-extracorporeal membrane oxygenation, p = 0.46) as well as the admission arterial lactate, pH and potassium. Their development was not different between the groups except for higher pH between the third and ninth hour of rewarming in the extracorporeal membrane oxygenation group. The hospital mortality was 10% in the extracorporeal membrane oxygenation group and 11.1% in the non-extracorporeal membrane oxygenation group with the median last Glasgow Coma Scale 15 and Cerebral Performance Score 1. Veno-arterial extracorporeal membrane oxygenation for severe hypothermia shows promising outcome data collected in an extracorporeal membrane oxygenation/extracorporeal cardiopulmonary resuscitation centre located in a European urban area. Except for presence of refractory cardiac arrest, the established hypothermia-related prognostic indicators did not differ between patients in need for extracorporeal membrane oxygenation and those rewarmed without extracorporeal membrane oxygenation.

Shoshin Beriberi and Severe Accidental Hypothermia as Causes of Heart Failure in a 6-Year-Old Child: A Case Report and Brief Review of Literature

Severe accidental hypothermia has been demonstrated to affect ventricular systolic and diastolic functions, and rewarming might be responsible of cardiovascular collapse. Until now, there have been only a few reports on severe accidental hypothermia, none of which involved children. Herein, we describe here a rare case of heart failure in a 6-year-old boy admitted to the emergency unit owing to severe hypothermia and malnutrition. After he was warmed up (core temperature of 27.2°C at admission), he developed cardiac arrest, requiring vasoactive amines administration, and veno-arterial extracorporeal membrane oxygenation. Malnutrition and refeeding syndrome might have caused the thiamine deficiency, commonly known as beriberi, which contributed to heart failure as well. He showed remarkable improvement in heart failure symptoms after thiamine supplementation. High-dose supplementation per os (500 mg/day) after reconstitution of an adequate electrolyte balance enabled the patient to recover completely within 2 weeks, even if a mild diastolic cardiac dysfunction persisted longer. In conclusion, we describe an original pediatric case of heart failure due to overlap of severe accidental hypothermia with rewarming, malnutrition, and refeeding syndrome with thiamine deficiency, which are rare independent causes of cardiac dysfunction. The possibility of beriberi as a cause of heart failure and adequate thiamine supplementation should be considered in all high-risk patients, especially those with malnutrition. Refeeding syndrome requires careful management, including gradual electrolyte imbalance correction and administration of a thiamine loading dose to prevent or correct refeeding-induced thiamine deficiency.

Successful Defibrillation of Four Hypothermic Patients with Witnessed Cardiac Arrest

Because of the limited evidence available, recommendations for defibrillation of hypothermic patients vary among published guidelines. To report successful defibrillation of four severely hypothermic patients with witnessed cardiac arrest. During a four-year period from 2014 to 2017, four of five hypothermic patients admitted to our institution with a history of sudden, unexpected ventricular fibrillation (core temperature: 24°C-27°C) were successfully defibrillated. Restoration of spontaneous circulation (ROSC) was possible after a single defibrillator shock (two patients) or during prolonged advanced life support cardiopulmonary resuscitation (two patients). Our patients and additional cases identified in the literature indicate that successful defibrillation is predominantly found in hypothermic patients with a core temperature above 24°C. Our data demonstrate that successful defibrillation and ROSC are possible in selected patients with severe accidental hypothermia and are perhaps more common than widely believed. These findings are of particular importance for mountain and wilderness rescue missions when transfer of an arrested patient to the nearest hospital providing extracorporeal rewarming is not possible. An automatic external defibrillator should be part of the medical equipment on any search or mountain rescue mission, in which the victim may have sustained accidental hypothermia.