Passive Rewarming Research Articles

Which rewarming therapy in hypothermia? A review of the randomised trials

AbstractIntroductionHypothermia may be encountered at some time in most parts of Australasia. There is a need to evaluate the merits of the various practical rewarming therapies available.MethodAn electronic and manual search of databases to identify randomised trials published between 1966 and 1996 inclusive which evaluated rewarming therapies in hypothermia.ResultsThere is a paucity of randomised trials on this subject and many of the rewarming therapies recommended in authoritative texts and reviews have never been evaluated in randomised clinical trials. In published trials core afterdrop is typically <0.5 C and is least with active core rewarming. Passive rewarming alone may be expected to raise core temperature by 0.75 C/hr and the addition of inhalation and/or forced air rewarming can be expected to at least double this.ConclusionsThe choice of rewarming therapy may be largely one of practicality and availability. Future rewarming research should focus on clinical outcomes in patients with moderate to severe hypothermia.

Accidental hypothermia: A potential life-threatening hazard of automobile platform lifts

The wheelchair/scooter of a patient with a relapsing-remitting form of multiple sclerosis was immobilized after inadvertent slippage of the rear wheels of his scooter off an automobile platform lift during travel. While waiting 45 min for the rescue squad, he developed mild hypothermia that responded to passive external rewarming techniques. This potentially life-threatening injury could have been prevented by using a platform lift equipped with full inboard and outboard roll-stop barriers on the platform.

Selective brain cooling in infant piglets after cardiac arrest and resuscitation: Crit Care Med 1996; 24/6: 1009–1017

Objectives To test the hypothesis that selective brain cooling could be performed in an infant model of cardiac arrest and resuscitation without changing core temperature and to study its acute effects on regional organ blood flow, cerebral metabolism, and systemic hemodynamics. Design Prospective, randomized, controlled study. Setting Research laboratory at a university medical center. Subjects Fourteen healthy infant piglets, weighing 3.5 to 6.0 kg. Interventions Piglets were anesthetized and mechanically ventilated, and had vascular catheters placed. Parietal cortex (superficial brain), caudate nucleus (deep brain), esophageal, and rectal temperatures were monitored. All animals underwent 6 mins of cardiac arrest induced by ventricular fibrillation, 6 mins of external cardiopulmonary resuscitation (CPR), defibrillation, and 2 hrs of reperfusion. Normal core temperature (rectal) was regulated in all animals. In seven control animals (group 1), brain temperature was not manipulated. In seven experimental animals (group 2), selective brain cooling was begun during CPR, using a cooling cap filled with minus 30 degrees C solution. Selective brain cooling was continued for 45 mins of reperfusion, after which passive rewarming was allowed. Regional blood flow (microspheres) and arterial and sagittal sinus blood gases were measured prearrest, during CPR, and at 10 mins, 45 mins, and 2 hrs of reperfusion. Measurements and Main Results Rectal temperature did not change over time in either group. In group 1, brain temperature remained constant except for a decrease of 0.6 degrees C at 10 mins of reperfusion. In group 2, superficial and deep brain temperatures were lowered to 32.8 plus minus 0.7 (SEM) degree C and 34.9 plus minus 0.4 degrees C, respectively, by 15 mins of reperfusion. Superficial and deep brain temperatures were further lowered to 27.8 plus minus 0.8 degrees C and 31.1 plus minus 0.3 degrees C, respectively, at 45 mins of reperfusion. Both temperatures returned to baseline by 120 mins. Cerebral blood flow was not different between groups at any time point, although there was a trend for higher flow in group 2 at 10 mins of reperfusion (314% of baseline) compared with group 1 (230% of baseline). Cerebral oxygen uptake was lower in group 2 than in group 1 (69% vs. 44% of baseline, p equals .02) at 45 mins of reperfusion. During CPR, aortic diastolic pressure was lower in group 2 than in group 1 (27 plus minus 1 vs. 23 plus minus 1 mm Hg, p equals .007). Myocardial blood flow during CPR was also lower in group 2 (80 plus minus 7 vs. 43 plus minus 7 mL/min/100 g, p equals .002). Kidney and intestinal blood flows were reduced during CPR in both groups; however, group 2 animals also had lower intestinal flow vs. group 1 at 45 and 120 mins of reperfusion. Conclusions Selective brain cooling by surface cooling can be achieved rapidly in an infant animal model of cardiac arrest and resuscitation without changing core temperature. Brain temperatures known to improve neurologic outcome can be achieved by this technique with minimal adverse effects. Because of its ease of application, selective brain cooling may prove to be an effective, inexpensive method of cerebral resuscitation during pediatric CPR.

The effects of forced-air warming on postbypass central and skin temperatures and shivering activity

Study Objective: To test the hypothesis that forced-air skin-surface warming used prophylactically after hypothermic cardiopulmonary bypass (CPB) would: (1) decrease the incidence and severity of postbypass shivering, (2) rapidly increase skin-surface temperatures when compared with standard warmed cotton blankets, and (3) not contribute to excessive central temperature elevation. Design: Prospective, randomized, nonblinded comparison of two rewarming techniques. Setting: Multidisciplinary intensive care unit at a tertiary care, private teaching hospital. Patients: Following hypothermic CPB, 47 patients underwent postoperative rewarming by using either conduction (warmed cotton blankets) or convection (forced-air cover) techniques. Measurements and Main Results: Central and skin temperatures were measured at 30-minute intervals for 5.5 hours postoperatively. Four lead electromyographic recordings were used to objectively document shivering activity. Antihypertensives, opioids, sedatives, and muscle relaxants were administered per patient need and recorded. The forced-air cover markedly decreased the overall incidence, duration, and magnitude of significant shivering compared with the warmed cotton blankets. Forced-air therapy produced clinically significant increases in skin surface temperatures, but avoided excessive central temperature elevation when compared with passive rewarming with cotton blankets. Conclusion: Convection warming, when compared with conductive warming with cotton blankets, limited the incidence, magnitude, and duration of shivering following hypothermic cardiac surgery. This suggests an important role of cutaneous thermal input in the mediation of the shivering response. The central tissue compartment is buffered from the effects of skin-surface warming and, thus, forced-air therapy will not lead to excessive central temperature elevation in this patient population when compared with cotton blanket rewarming.

Selective brain cooling in infant piglets after cardiac arrest and resuscitation.

To test the hypothesis that selective brain cooling could be performed in an infant model of cardiac arrest and resuscitation without changing core temperature and to study its acute effects on regional organ blood flow, cerebral metabolism, and systemic hemodynamics. Prospective, randomized, controlled study. Research laboratory at a university medical center. Fourteen healthy infant piglets, weighing 3.5 to 6.0 kg. piglets were anesthetized and mechanically ventilated, and had vascular catheters placed. Parietal cortex (superficial brain), caudate nucleus (deep brain), esophageal, and rectal temperatures were monitored. All animals underwent 6 mins of cardiac arrest induced by ventricular fibrillation, 6 mins of external cardiopulmonary resuscitation (CPR), defibrillation, and 2 hrs of reperfusion. Normal core temperature (rectal) was regulated in all animals. In seven control animals (group 1), brain temperature was not manipulated. In seven experimental animals (group 2), selective brain cooling was begin during CPR, using a cooling cap filled with -30 degrees C solution. Selective brain cooling was continued for 45 mins of reperfusion after which passive rewarming was allowed. Regional blood flow (microspheres) and arterial and sagittal sinus blood gases were measured prearrest, during CPR, and at 10 mins, 45 mins, and 2 hrs of reperfusion. Rectal temperature did not change over time in either group. In group 1, brain temperature remained constant except for a decrease of 0.6 degrees C at 10 mins of reperfusion. In group 2, superficial and deep brain temperatures were lowered to 32.8 +/- 0.7 (SEM) degrees C and 34.9 +/- 0.4 degrees C, respectively, by 15 mins of reperfusion. Superficial and deep brain temperatures were further lowered to 27.8 +/- 0.8 degrees C and 31.1 +/- 0.3 degrees C, respectively, at 45 mins of reperfusion. Both temperatures returned to baseline by 120 mins. Cerebral blood flow was not different between groups at any time point, although there was a trend for higher flow in group 2 at 10 mins of reperfusion (314% of baseline) compared with group 1 (230% of baseline). Cerebral oxygen uptake was lower in group 2 than in group 1 (69% vs. 44% of baseline, p=.02) at 45 mins of reperfusion. During CPR, aortic diastolic pressure was lower in group 2 than in group 1 (27 +/- 1 vs. 23 +/- 1 mm Hg, p = .007). Myocardial blood flow during CPR was also lower in group 2 (80 +/- 7 vs. 43 +/- 7 mL/min/100 g, p=.002). Kidney and intestinal blood flows were reduced during CPR in both groups; however, group 2 animals also had lower intestinal flow vs. group 1 at 45 and 120 mins of reperfusion. Selective brain cooling by surface cooling can be achieved rapidly in an infant animal model of cardiac arrest and resuscitation without changing core temperature. Brain temperatures known to improve neurologic outcome can be achieved by this technique with minimal adverse effects. Because of its ease of application, selective brain cooling may prove to be an effective, inexpensive method of cerebral resuscitation during pediatric CPR.

External rewarming and age in mildly hypothermic patients after cardiac surgery

To compare the effects of two external rewarming methods on body core temperature and the rate of rewarming between two age groups (less than 65 years, 65 years or more) of adult, mildly hypothermic patients who have undergone cardiac surgery, during the immediate postoperative period. Stratified, randomized clinical trial. Five-bed cardiac surgical intensive care unit in a large teaching-research institution. Thirty-two white patients who had undergone cardiac surgery and who had mildly hypothermic body core temperatures (33 degrees to 35 degrees C) immediately after the surgery. Body core temperature was measured with a pulmonary artery catheter thermistor at the time of external rewarming method application and at 60, 90, and 150 minutes afterward. Rate of rewarming was measured as body core temperature change in degrees Celsius per hour (at 36.6 degrees C, minus body core temperature when external rewarming method was applied, divided by total rewarming time). Temperatures were recorded six times at intervals of 15 minutes; then every 30 minutes until a value of 36.6 degrees C was obtained, at which time the blanket was removed; then hourly for 8 hours. Either a fluid-filled circulating blanket (active-conductive external rewarming) or a reflective blanket (passive-reflective external rewarming) was applied immediately after core temperature was measured on admission to the cardiac surgical intensive care unit after surgery. External rewarming methods affected body core temperature differently at different times, and there were significant differences in body core temperature across the time periods (p < 0.05). Both active and passive external rewarming methods showed a sigmoidal rewarming pattern without a downward temperature drift. The fluid-filled circulating blanket produced a quicker and steeper body core temperature change in the early rewarming phase; the reflective blanket resulted in a more gradual temperature rise. Age did not significantly affect body core temperature, nor did age or external rewarming method significantly influence the rate of rewarming, although total rewarming time was longer for those of more advanced age. Seven subjects with passive rewarming method experienced body core temperature overshoot during the 8-hour period after blanket removal. In this study, conduction and reflection of radiant heat were equally effective in producing an acceptable rate of rewarming but contributed to different internal patterns in core rewarming. The average total rewarming time with the active external rewarming method was 1 hour shorter than with the passive external rewarming method.

Akute intermittierende hypothalamische Hypothermie bei Herpes-Simplex-Enzephalitis

Acute-onset hypothalamic hypothermia is a rare and usually prefinal symptom of severe damage of midline structures of the brain and accompanied by other vegetative and endocrine dysfunctions. We describe a 67-year-old female who developed an acute intermittent hypothalamic hypothermia in the course of a herpes simplex encephalitis involving the left temporal lobe and periventricular structures. After the clinical status and CSF cell count began to improve, the patient showed the vegetative and behavioural signs of active heat dissipation. Within 9 hours the rectal temperature fell from 37.5 to 32.7 °C. The clinical picture and the rapidity of cooling point to intermittent downregulation of the central hypothalamic thermostat. The patient showed rapid response to passive rewarming and intravenous application of catecholamines. Thermoregulation remained normal thereafter and there were no signs of endocrine disorders. The reported case demonstrates that acute hypothalamic hypothermia can occur in the course of Herpes simplex encephalitis. It can be an intermittent, isolated sign of hypothalamic involvement and full restitution of hypothalamic function is possible.

Comparative effectiveness of hypothermia rewarming techniques: radio frequency energy vs. warm water

The purpose of this study was to compare the rewarming effectiveness of a radio frequency coil (13.56 MHz) at a specific absorption rate (SAR) of 2.5 W/kg (RF) with warm water immersion (40 °C) (WW) and an insulated mummytype insulating sack (IS) under simulated field conditions. Four male subjects, ages 24–35, were immersed in 10 °C water for up to 90 min or until their rectal temperatures (T re) decreased to 35 °C. Each subject had 3 trials in which they were immersed. After each immersion, rewarming was accomplished with either RF, WW, or IS, so that each subject was rewarmed once with each method. Comparisons of the 3 rewarming methods were based on the rate of increase of T re during rewarming ( T re t ), T re 60 min after the start of rewarming (T re60), the time-interval measured from extraction from the water to the end of afterdrop (t ad), and the magnitude of any observed T re afterdrop (T ad). WW had significantly greater T re t and T re60 than either RF or IS ( P < 0.03) and a smaller t ad than IS ( P < 0.05). IS had significantly greater T ad than either WW or RF ( P < 0.05). No significant differences in T re t , T re60, or t ad were observed between IS and RF. The results of this study indicate that for mildly hypothermic individuals, active rewarming with RF at a SAR of 2.5 W/kg is less effective than WW and roughly equivalent to passive rewarming with IS.

Cold Injuries

There are two categories of cold injury. The first is hypothermia, which is a systemic injury to cold, and the second is frostbite, which is a local injury. Throughout history, entire armies, from George Washington to the Germans on the Russian Front in World War II, have fallen prey to prolonged cold exposure. Cold injury is common and can occur in all seasons if ambient temperature is lower than the core body temperature. In the 1985 Boston Marathon, even though it was 76 degrees and sunny, there were 75 runners treated for hypothermia. In general, humans adapt poorly to cold exposure. Children are at particular risk because of their relatively greater surface area/body mass ratio, causing them to cool even more rapidly than adults. Because of this, the human's best defense against cold injury is to limit his/her exposure to cold and to dress appropriately. If cold injury has occurred and is mild, often simple passive rewarming such as dry blankets and a warm room are sufficient treatment.

Noncardiogenic Pulmonary Edema Associated with Accidental Hypothermia

The pulmonary system may be significantly affected by hypothermia. The association between NCPE and hypothermia is controversial. A 59-year-old man with mild hypothermia presented with NCPE after passive external rewarming following accidental immersion in water. The patient's course was uneventful after 48 h, allowing immediate withdrawal of assisted ventilation and supplemental oxygen.

Closed thoracic cavity lavage in the treatment of severe hypothermia in human beings

Life-threatening hypothermia can be treated by active and passive rewarming techniques, the treatment of choice being partial cardiopulmonary bypass. The use of closed thoracic cavity lavage has been evaluated in animals, but no formal presentations in human beings have been reported. We report two cases in which rapid rewarming in severe hypothermia was accomplished when cardiopulmonary bypass was not available.

Influence of skeletal muscle glycogen on passive rewarming after hypothermia.

To examine the influence of muscle glycogen on the thermal responses to passive rewarming subsequent to mild hypothermia, eight subjects completed two cold-water immersions (18 degrees C), followed by 75 min of passive rewarming (24 degrees C air, resting in blanket). The experiments followed several days of different exercise-diet regimens eliciting either low (LMG; 141.0 +/- 10.5 mmol.kg.dry wt-1) or normal (NMG; 526.2 +/- 44.2 mmol.kg.dry wt-1) prewarming muscle glycogen levels. Cold-water immersion was performed for 180 min or to a rectal temperature (Tre) of 35.5 degrees C. In four subjects (group A, body fat = 20 +/- 1%), postimmersion Tre was similar to preimmersion Tre for both trials (36.73 +/- 0.18 vs. 37.26 +/- 0.18 degrees C, respectively). Passive rewarming in group A resulted in an increase in Tre of only 0.13 +/- 0.08 degrees C. Conversely, initial rewarming Tre for the other four subjects (group B, body fat = 12 +/- 1%) averaged 35.50 +/- 0.05 degrees C for both trials. Rewarming increased Tre similarly in group B during both LMG (0.76 +/- 0.25 degrees C) and NMG (0.89 +/- 0.13 degrees C). Afterdrop responses, evident only in those individuals whose body core cooled during immersion (group B), were not different between LMG and NMG. These data support the contention that Tre responses during passive rewarming are related to body insulation. Furthermore these results indicate that low muscle glycogen levels do not impair rewarming time nor alter after-drop responses during passive rewarming after mild-to-moderate hypothermia.

Multicenter hypothermia survey

A multicenter survey evaluated the clinical presentation, treatment, and outcome of accidental hypothermia. Data were collected from 13 emergency departments, with 401 of the 428 cases presenting during a two-year study period. Core temperatures ranged from 35 C to 15.6 C (mean, 30.57 C +/- 3.53) with 272 cases (63.6%) less than or equal to 32.2 C. There were no significant differences by age in presenting temperature, rewarming strategies, or mortality. The first hour rewarming rate was significantly (P less than .05) faster in the population less than or equal to 59 years (1.08 +/- 1.39 C/hr) than in those greater than or equal to 60 years (0.75 +/- 1.16 C/hr). Male core temperatures averaged 30.27 +/- 3.44 C versus female temperatures of 31.1 +/- 3.61 C. There were no clinically significant differences in male (N = 296) versus female (N = 132) profiles. High ethanol levels (315 to 800 mg%) did not affect outcome. Nine of 27 (33%) patients who received CPR initiated in the field survived, versus six of 14 (43%) with CPR begun in the ED. The profile of the CPR versus non-CPR population differed significantly (P less than .05) in location (outdoors), initial temperature (24.8 +/- 3.77 C vs 30.94 +/- 3.12 C), third-hour rewarming rate (2.28 +/- 1.53 C vs 1.17 +/- 1.18 C/hr), and numerous laboratory parameters. Tracheal intubation was performed without incident in 117 cases, of which 97 were less than or equal to 32.2 C. There were 73 fatalities (17.1%). Of these, 84.9% (N = 62) were less than or equal to 32.2 C. Predisposing conditions in this group included "serious" illness (30), systemic infection (28), trauma (15), immersion (ten), frostbite (seven), and overdose (two). The initial pulse, hemoglobin, and first-hour rewarming rate was lower in the deceased population, while the potassium, urea nitrogen, creatinine, and phosphorus were elevated. Excluding treatment combinations, outcome with exclusive use of a single rewarming strategy was passive external rewarming, 14 deaths below 32.2 C, 13 above; active external rewarming, six deaths below 32.2 C, two above; active core rewarming, 38 deaths below 32.2 C, none above. Refinements of the American Heart Association's CPR standards in hypothermia and a Hypothermia Survival Index are proposed.

Accidental hypothermia. Review of the literature.

The pathophysiology and treatment of accidental hypothermia are discussed. Special attention is paid to the pathophysiologic problems of rewarming. For severely hypothermic patients we would recommend peritoneal dialysis as the method of choice for rewarming in a hospital situation. In a "field situation" passive or slow active rewarming is recommended.

A plastic head cover to reduce surgical heat loss

Objective: To compare the effects of two external rewarming methods on body core temperature and the rate of rewarming between two age groups (less than 65 years, 65 years or more) of adult, midly hypothermic patients who have undergone cardiac surgery, during the immediate postoperative period.Design: Stratified, randomized clinical trial.Setting: Five-bed cardiac surgical intensive care unit in a large teaching-research institution.Subjects: Thirty-two white patients who had undergone cardiac surgery and who had midly hypothermic body core temperatures (33° to 35°C) immediately after the surgery.Outcome Measures: Body core temperature was measured with a pulmonary artery catheter thermistor at the time of external rewarming method application and at 60, 90, and 150 minutes afterward. Rate of rewarming was measured as body core temperature change in degrees Celsius per hour (at 36.6°C, minus body core temperature when external rewarming method was applied, divided by total rewarming time). Temperatures were recorded six times at intervals of 15 minutes; then every 30 minutes until a value of 36.6°C was obtained, at which time the blanket was removed; then hourly for 8 hours.Intervention: Either a fluid-filled circulating blanket (active-conductive external rewarming) or a reflective blanket (passive-reflective external rewarming) was applied immediately after core temperature was measured on admission to the cardiac surgical intensive care unit after surgery.Results: External rewarming methods affected body core temperature differently at different times, and there were significant differences in body core temperature across the time periods (p<0.05). Both active and passive external rewarming methods showed a sigmoidal rewarming pattern without a downward temperature drift. The fluid-filled circulating blanket produced a quicker and steeper body core temperature change in the early rewarming phase; the reflective blanket resulted in a more gradual temperature rise. Age did not significantly affect body core temperature, nor did age or external rewarming method significantly influence the rate of rewarming, although total rewarming time was longer for those of more advanced age. Seven subjects with passive rewarming method experienced body core temperature overshoot during the 8-hour period after blanket removal.Conclusions: In this study, conduction and reflection of radiant heat were equally effective in producing an acceptable rate of rewarming but contributed to different internal patterns in core rewarming. The average total rewarming time with the active external rewarming method was 1 hour shorter than with the passive external rewarming method.

Accidental hypothermia: A survivor of 12 episodes

Accidental hypothermia is defined as an environmentally induced reduction of the core body temperature to 35 °C or below, where there is no primary endocrine or preoptic anterior hypothalmic dysfunction. We report a survivor of 12 episodes of accidental hypothermia. A comparison of his rewarming rates with passive external versus active core rewarming by inhalation of heated humidified oxygen via nasotracheal tube is provided. Multiple predisposing factors contributed to the repeated episodes of hypothermia. Anatomic causes of repeated nonaccidental hypothermia were excluded.

Thermoregulatory Failure Secondary to Acute Illness

We report on six patients in whom hypothermia secondary to acute illnesses, including pneumonia, congestive heart failure, renal failure, drug overdose, and hypoglycemia, developed. Complications that occurred were metabolic acidosis in six patients, altered sensorium in five, bradyarrhythmia in three, and hyperamylasemia in two. All patients failed to demonstrate a shivering response and represent cases of acute thermoregulatory failure. Five of the six patients survived. In the course of treatment, the choice of active or passive rewarming should be based on whether or not normal thermoregulatory mechanisms are intact.

Hypothermia

Letters and Corrections1 April 1979HypothermiaGLENN HAMILTON, M.D., PETER ROSEN, M.D.GLENN HAMILTON, M.D.Search for more papers by this author, PETER ROSEN, M.D.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-90-4-721 SectionsAboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail ExcerptTo the editor: The article "Hypothermia: Pathophysiology, Clinical Settings, and Management" by Dr. Reuler in the October issue (1) is an excellent update on pathophysiology, but recent advances in management have been neglected. We specifically refer to the article by O'Keeffe (2) describing management experience with 62 cases of hypothermia at Denver General Hospital. The modality of therapy found to be most useful was passive rewarming with warm blankets. Fifty-six patients (90%) with stable blood pressure were treated only by frequent changing of warm blankets. Twenty-eight in this group had temperatures less than 32 °C. Only two patients died, one...

Accidental hypothermia. Associated diagnoses and prognosis in a common problem.

Sixteen patients with accidental hypothermia were admitted to the medical service of a general hospital in a one-year period. Analysis of the clinical status of the patients and the associated disease states showed that the underlying disease was more important in determining survival than the method of rewarming. Seven of eight patients with marked underlying organ system disease died, while all eight patients without severe organic disease survived even though the degree of hypothermia and time required for rewarming were similar in the two series. Slow passive rewarming is adequate therapy for most hypothermic patients, and major therapeutic efforts should be directed at underlying disease processes rather than the physiologic response to hypothermia.

Clinical study of 39 cases of accidental hypothermia in adults

SummaryThe authors review 39 cases of adult patients with accidental hypothermia. The frequency of this affection is presumably higher than generally thought, especially in normal but aged patients and in different pathological conditions which interfere with the mechanisms of thermoregulation. Eventhough the diagnosis of hypothermia is a simple one, it is probably often missed because the symptoms of the causal disease are frequently masking it, but also because the characteristic signs of hypothermia appear only when the temperature is really low (under 33°C).Clinical manifestations of hypothermia are quite various and are largely depending on the causal disease. Shivering, muscular hypertonia, skin modifications, hemodynamic disturbances, bradycardia and bradypnea are usually observed. The authors underline the possible absence of severe alterations of conscience, even when the central temperature reaches 26°C. Biological tests are generally slightly perturbed.The prognosis is closely related to the prognosis of the causal disease. The major complications are hypotension, cardiac arrhythmias, infectious bronchopulmonary complications. Intensive therapy (active or passive rewarming, maintenance of a good circulatory state, artificial ventilation if necessary) and a constant watching of these patients in an intensive care unit are a necessity. In these conditions, and providing that the causal affection is reversible, the prognosis of hypothermia is good, even if the central temperature is deeply lowered.