Rewarming In Accidental Hypothermia Research Articles

When Research Serves Good Purposes

When Research Serves Good Purposes

Endovascular rewarming in the emergency department for moderate to severe accidental hypothermia

BackgroundEndovascular temperature control catheters can be utilized for emergent rewarming in accidental hypothermia. The purpose of this study was to compare patients with moderate to severe hypothermia rewarmed with an endovascular temperature control catheter versus usual care at our institution. MethodsWe conducted a retrospective, observational cohort study of patients with moderate to severe accidental hypothermia (core body temperature less than 32°C) in the Emergency Department of an urban, tertiary care medical center. We identified the rewarming techniques utilized for each patient, including those who had an endovascular temperature control catheter placed (Quattro© or Icy© catheter, CoolGuard© 3000 regulation system, Zoll Medical). Rewarming rates and outcomes were compared for patients with and without the endovascular temperature control catheter. We systematically screened for procedural complications. ResultsThere were 106 patients identified with an initial core temperature less than or equal to 32°C; 52 (49%) patients rewarmed with an endovascular temperature control catheter. Other methods of rewarming included external forced-air rewarming (85, 80%), bladder lavage (17, 16%), gastric lavage (10, 9%), closed pleural lavage (6, 6%), and peritoneal lavage (3, 3%). Rate of rewarming did not differ between the groups with and without catheter-based rewarming (1.3°C/h versus 1.0°C/h, difference 0.3°C, 95% confidence interval [CI] of the difference 0–0.6°C) and neither did survival (70% versus 71%, difference 1%, 95% CI -17 to 20%). We did not identify any significant vascular injuries resulting from endovascular catheter use. ConclusionThe endovascular temperature control system was not associated with an increased rate of rewarming in this cohort with moderate to severe hypothermia; however, this technique appears to be safe and feasible.

Schwerunterkühlte

Cardiac arrest not responding to any treatment is the most dangerous difficulty of severe accidental hypothermia at sea. The cooling down of brain tissue correlates with a remarkable increase of cerebral oxygen deficiency tolerance. Within the SARRRAH project (Search and Rescue, Resuscitation and Rewarming in Accidental Hypothermia) procedures and equipment for sea rescue purposes have been developed to enable seamen to perform a sufficient mechanical long-term resuscitation, even under rough conditions and limited manpower. A specially modified combitube is being used as a safe artificial airway device. The use of active compression-decompression cardiopulmonary resuscitation (ACD-CPR) in combination with an inspiratory impedance threshold device and an oxygen demand valve causes a sufficient blood circulation to keep the inner organ tissues vital. Ships’ crew members and maritime rescue staff need a simple additional advanced First Aid training to be enabled to start life-saving procedures by themselves, without professional help.

Reduction and elimination of systemic heparinization during cardiopulmonary bypass

After extensive experimental evaluation, heparin-coated perfusion equipment was clinically evaluated with low or no systemic heparinization in three different groups of patients (n = 47). In group 1, resection of descending thoracic aortic aneurysms (n = 24) was performed with heparin-coated equipment used for left heart bypass (n = 12) or partial cardiopulmonary bypass (n = 12) for proximal unloading and distal protection (heparin 5000 IU, autotransfusion). All devices remained functional throughout the procedures and no systemic emboli were detected. The sole death (1 of 24, 4%) occurred in a patient with ruptured thoracoabdominal aortic aneurysm requiring operation in extremis. Paraparesis with spontaneous recovery occurred in one patient (1 of 24, 4%). In group 2, coronary artery revascularization randomized for low (activated clotting time greater than 180 seconds) versus full (activated clotting time greater than 480 seconds) systemic heparinization was prospectively analyzed in 22 patients. All patients recovered without sequelae, and no myocardial infarction was diagnosed. Low dose of heparin (8041 +/- 1270 IU versus 52,500 +/- 17,100 IU; p less than 0.0005) resulted in reduced protamine requirements (7875 +/- 1918 IU versus 31,400 +/- 14,000 IU; p less than 0.0005), reduced blood loss (831 +/- 373 ml versus 2345 +/- 1815 ml; p less than 0.01), reduced transfusion requirements of homologous blood products (281 +/- 415 ml versus 2731 +/- 2258 ml; p less than 0.001), and less patients transfused (5 of 12 versus 10 of 10; p less than 0.05). Lower D-dimer levels in the group perfused with low systemic heparinization (0.50 +/- 0.43 mg/L versus 1.08 +/- 0.59 mg/L; p less than 0.05) were attributed to the absence of cardiotomy suction in this group. In group 3, rewarming in accidental hypothermia by cardiopulmonary bypass was successfully performed without systemic heparinization in a patient with hypothermic cardiac arrest (23.3 degrees C) and intracranial trauma. We conclude that systemic heparinization for clinical cardiopulmonary bypass can be reduced and eliminated in selected patients if perfusion equipment with improved biocompatibility is used. Bypass-induced morbidity can be reduced.

REWARMING FOR ACCIDENTAL HYPOTHERMIA

REWARMING FOR ACCIDENTAL HYPOTHERMIA

Metabolic Aspects of Spontaneous Rewarming in Accidental Hypothermia and Hypothermic Myxoedema

The metabolic background to spontaneous rewarming has been studied in 70 euthyroid patients with accidental hypothermia and in 18 patients with hypothermic myxoedema by correlating their rates of rewarming with their initial serum protein bound iodine (PBI), blood glucose, plasma free fatty acid (FFA), plasma 11-hydroxycorticosteroid (11-OHCS), and arterial PO2 levels. In the hypothyroid group, the rates of spontaneous rewarming correlated significantly with only the PBI levels (P < 0.05). In the euthyroid group, there may be an inverse correlation between the rate of spontaneous rewarming and age (P < 0.10). The roles played in the rewarming process by the other parameters measured are discussed, particularly in relation to individual clinical situations.

Rapid active external rewarming in accidental hypothermia

Rapid active external rewarming in accidental hypothermia