Influence of acute beetroot juice supplementation on cold-induced vasodilation and fingertip rewarming.

PURPOSE: Vasoactive ingredients in beetroot (BR) such as nitrate are known to induce vasodilation in temperate conditions. This study investigated the effect of BR ingestion on cold induced vasodilation (CIVD) and rewarming of finger skin temperature (Tfing) during and after hand immersion in cold water. METHODS: Twenty healthy males (mean ± SD; age 22.2 ± 0.7 years, height 172.6 ± 6.0 cm, body mass 61.3 ± 11.7 kg) repeated a hand cold water immersion test twice with prior BR or water beverage ingestion (randomised order). They rested for 2 h in thermoneutral conditions (27 °C, 40% relative humidity) after consuming the beverage, then immersed their non-dominant hand in 8 °C water for 30 min. They then rewarmed their hand in the ambient air for 20 min. Skin temperature at seven body sites, Tfing, finger skin blood flow (SkBFfing), and blood pressure were measured. RESULTS: During hand immersion parameters of CIVD (Tfing and SkBFfing) were not different between BR and water conditions although skin temperature gradient from proximal to distal body sites was significantly smaller with BR (P < 0.05). During rewarming, SkBFfing and cutaneous vascular conductance were significantly higher with BR than with water (P < 0.05). The rewarming speed in Tfing and SkBFfing was significantly faster with BR at 15- (BR 1.24 ± 0.22 vs water 1.11 ± 0.26 °C/min) and 20-min rewarming (P < 0.05). Additionally, individuals with slower rewarming speed with water demonstrated accelerated rewarming with BR supplementation. CONCLUSION: BR accelerated rewarming in Tfing and SkBFfing after local cold stimulus, whereas, CIVD response during hand cold immersion was not affected by BR ingestion.

Clinical utilization of a sous vide device in the acute rewarming of frostbitten extremities.

The current standard of care for acute frostbite rewarming is the use of a circulating warm water bath at a temperature of 37 °C to 39 °C. There is no standardized method to achieve this. Manual management of a warm water bath can be inefficient and time consuming. This case describes the clinical use of a sous vide cooking device to create and maintain a circulating warm water bath to rewarm acute frostbite. A 34 year-old male presented to the emergency department with acute frostbite. Each of the patient's feet were placed in a water bath with a sous vide device attached to the side of the basin and set to 38 °C. Temperatures were recorded every 2 m from 2 thermometers. Once target temperature was achieved, the extremities were rewarmed for 30 m. The water baths required an average of 25 m to reach target temperature and maintained the target temperature within ±1 °C for the duration of the rewarming. The extremities were clinically thawed in one session and there were no adverse events. The patient was seen by plastic and vascular surgery and admitted to the hospital for conservative management. He was discharged on hospital day 3 and did not require any amputations. A sous vide device can be used clinically to heat and maintain a water bath and successfully rewarm frostbitten extremities in one 30 m cycle. No adverse events were reported and providers rated this as a convenient method of water bath management.

Effect of prewarming on body temperature in short-term bladder or prostatic transurethral resection under general anesthesia: A randomized, double-blind, controlled trial.

Perioperative hypothermia causes postoperative complications. Prewarming reduces body temperature decrease in long-term surgeries. We aimed to assess the effect of different time-periods of prewarming on perioperative temperature in short-term transurethral resection under general anesthesia. Randomized, double-blind, controlled trial in patients scheduled for bladder or prostatic transurethral resection under general anesthesia. Eligible patients were randomly assigned to receive no-prewarming or prewarming during 15, 30, or 45 min using a forced-air blanket in the pre-anesthesia period. Tympanic temperature was used prior to induction of anesthesia and esophageal temperature intraoperatively. Primary outcome was the difference in core temperature among groups from the induction of general anesthesia until the end of surgery. Repeated measures multivariate analysis of covariance modeled the temperature response at each observation time according to prewarming. We examined modeled contrasts between temperature variables in subjects according to prophylaxis. We enrolled 297 patients and randomly assigned 76 patients to control group, 74 patients to 15-min group, 73 patients to 30-min group, and 74 patients to the 45-min group. Temperature in the control group before induction was 36.5 ± 0.5 °C. After prewarming, core temperature was significantly higher in 15- and 30-min groups (36.8 ± 0.5 °C, p = 0.004; 36.7 ± 0.5 °C, p = 0.041, respectively). Body temperature at the end of surgery was significantly lower in the control group (35.8 ± 0.6 °C) than in the three prewarmed groups (36.3 ± 0.6 °C in 15-min, 36.3 ± 0.5 °C in 30-min, and 36.3 ± 0.6 °C in 45-min group) (p < 0.001). Prewarming prior to short-term transurethral resection under general anesthesia reduced the body temperature drop during the perioperative period. These time-periods of prewarming also reduced the rate of postoperative complications.Study Registration Registered at ClinicalTrials.gov (Identifier: NCT03630887).

Use of the new preservation solution Custodiol-MP for ex vivo reconditioning of kidney grafts.

Organ shortage and the increasing use of extended criteria donor grafts for transplantation drives efforts for more efficient organ preservation strategies from simple cold storage toward dynamic organ reconditioning. The choice of a suitable preservation solution is of high relevance in different organ preservation or reconditioning situations. Custodiol-MP is a new machine perfusion solution giving the opportunity to add colloids according to organ requirements. The present study aimed to compare new Custodiol-MP with clinically established Belzer MPS solution. Porcine kidneys were ischemically predamaged and cold stored for 20 hours. Ex vivo machine reconditioning was performed either with Custodiol-MP (n = 6) or with Belzer MPS solution (n = 6) for 90 minutes with controlled oxygenated rewarming up to 20°C. Kidney function was evaluated using an established ex vivo reperfusion model. In this experimental setting, differences between both types of perfusion solutions could not be observed. Machine perfusion with Custodiol-MP resulted in higher creatinine clearance (7.4 ± 8.6 mL/min vs. 2.8 ± 2.5 mL/min) and less TNC perfusate levels (0.22 ± 0.25 ng/mL vs. 0.09 ± 0.08 ng/mL), although differences did not reach significance. For short-term kidney perfusion Custodiol-MP is safe and applicable. Particularly, the unique feature of flexible colloid supplementation makes the solution attractive in specific experimental and clinical settings.

Successful Defibrillation at a Core Temperature of 18.2 Degrees Celsius.

Both the temperature at which defibrillation can be effectively used and how often it should be repeated in severe accidental hypothermia have not been definitely established. Current recommendations are based mainly on expert opinion and suggest withholding defibrillation after 3 shocks when the core temperature is below 30°C (86°F). However, growing evidence supports the effectiveness of defibrillation in patients with a core temperature below 30°C (86°F). We present a case of successful defibrillation of a 54-y-old, severely hypothermic patient with a core temperature of 18.2°C (64.8°F). The shock was delivered automatically by an implanted cardioverter-defibrillator shortly after the implementation of extracorporeal rewarming. The patient survived and was discharged from the hospital neurologically intact. It might be reasonable to consider defibrillation attempts in severely hypothermic patients despite current guidelines to the contrary. Increasing coronary perfusion using extracorporeal circulation may result in a better response to defibrillation.

Epinephrine at 25°C Core Body Temperature and During Rewarming: Case Report of Successful Infant Resuscitation After Cold Water Submersion.

Epinephrine plays a controversial role in accidental hypothermia (<30°C). We report its use in the advanced life support of a 13-month-old white girl with pulseless electrical activity and 25°C core body temperature after 32 minutes of submersion in a fast-running Swiss mountain stream at 8°C. Two doses of epinephrine (10 µg/kg) were given in the field, followed by 12 doses (10 µg/kg) and an infusion of 0.1 µg/kg per minute during rewarming. Spontaneous circulation returned at 29.5°C after 2.5 hours of cardiopulmonary resuscitation. Neurologic long-term outcome was excellent. We conclude that in the presence of nonshockable rhythm the benefits of epinephrine may outweigh the risks of side effects when used in pediatric advanced life support for accidental hypothermia.

Early treatment of frostbite with hyperbaric oxygen and pentoxifylline: a case report.

While several published cases have reported tissue preservation with hyperbaric oxygen (HBO2) after frostbite, its routine use is not endorsed by expert consensus. We report a case of possible frostbite injury to the toes of both feet and the plantar surface of the left foot in a 17-year-old male patient. The exposure history included two episodes of rewarming followed by refreezing in the field during a hike through knee-deep snow without adequate clothing. The patient also sustained full-thickness ice abrasions to both anterior shins. The patient was evaluated within 60 minutes after self-rewarming. He was treated with 400 mg oral pentoxifylline three times a day and HBO2 at 2.4 atmospheres absolute for 90 minutes twice a day for a total of 13 treatments. Therapy was initiated approximately two hours from the estimated time of rewarming. Both feet recovered full sensation, and the patient had no tissue loss on his feet and and no functional impairment. The patient was followed for 12 months from injury. This case report highlights the difficulty health care providers face to accurately diagnose frostbite within the first 24 hours of injury, prior to development of more definitive signs and symptoms. Early treatment during this critical period may preserve tissue and function.

The effects of a forced-air warming system plus electric blanket for elderly patients undergoing transurethral resection of the prostate: A randomized controlled trial.

BACKGROUND: Perioperative inadvertent hypothermia in elderly urology patients undergoing transurethral resection of the prostate (TURP) is a well-known serious complication, as it increases the risk of myocardial ischemia, blood loss, and surgical wound infection. We conducted this prospective randomized controlled trial to evaluate the combined effect of a forced-air warming system and electric blanket in elderly TURP patients. METHODS: Between January 2015 and October 2017, we recruited 443 elderly male patients undergoing elective TURP with subarachnoid blockade (SAB). These were randomly divided into 3 groups: group E (intraoperative warming using electric blankets set to 38°C; n = 128); group F (intraoperative warming using a forced-air warmer set to 38°C; n = 155) and group FE (intraoperative warming using a forced-air warmer plus electric blankets, both set to 38°C; n = 160). The primary outcome was shivering and their grades. Hemodynamic changes, esophageal temperature, recovery time, incidences of adverse effects, and patient and surgeon satisfaction were also recorded. RESULTS: Baseline characteristics showed no significant differences when compared across the 3 groups (P >.05). Compared with groups E and F, both HR and mean arterial pressure (MAP) in group FE were significantly decreased from T6 to T10 (P <.05). Compared with groups E and F, esophageal temperature in group FE increased significantly from T5 to T10 (P <.05). Compared with group E, esophageal temperature in group F was significantly increased from T5 to T10 (P <.05). Compared with groups F and FE, post-anesthesia care unit (PACU) recovery time was longer in group E, while compared with group F, PACU recovery time was shorter in group FE (P <.05). Compared to patients in groups E and F, those in group FE had a significantly lower incidence of arrhythmia and shivering (P <.05). The number of patients with shivering grades 0 to 3 was higher in group E than in other groups, while the number of patients with shivering grade 2 was significantly higher in group F than in group FE (P <.05). Patient and surgeon satisfaction scores were higher in group FE than in groups E and F (P <.05). CONCLUSIONS: Use of a forced-air warming system combined with an electric blanket was an effective method with which to retain warmth among elderly TURP patients.

Effects of dietary nitrate supplementation on the response to extremity cooling and endothelial function in individuals with cold sensitivity. A double blind, placebo controlled, crossover, randomised control trial.

Individuals with cold sensitivity have low peripheral skin blood flow and skin temperature possibly due to reduced nitric oxide (NO•) bioavailability. Beetroot has a high concentration of inorganic nitrate and may increase NO-mediated vasodilation. Using a placebo-controlled, double blind, randomised, crossover design, this study tested the hypotheses that acute beetroot supplementation would increase the rate of cutaneous rewarming following a local cold challenge and augment endothelium-dependent vasodilation in cold sensitive individuals. Thirteen cold sensitive participants completed foot and hand cooling (separately, in 15 °C water for 2 min) with spontaneous rewarming in 30 °C air whilst skin temperature and cutaneous vascular conductance (CVC) were measured (Baseline). On two further separate visits, participants consumed 140 ml of either concentrated beetroot juice (nitrate supplementation) or nitrate-depleted beetroot juice (Placebo) 90 min before resting seated blood pressure was measured. Endothelial function was assessed by measuring CVC at the forearm, finger and foot during iontophoresis of 1% w/v acetylcholine followed by foot and hand cooling as for Baseline. Plasma nitrite concentrations significantly increased in nitrate supplementation compared to Placebo and Baseline (502 ± 246 nmol L-1; 73 ± 45 nmol L-1; 74 ± 49 nmol L-1 respectively; n = 11; P < 0.001). Resting blood pressure and the response to foot and hand cooling did not differ between conditions (all P > 0.05). Nitrate supplementation did not alter endothelial function in the forearm, finger or foot (all P > 0.05) compared to Placebo. Despite a physiologically meaningful rise in plasma nitrite concentrations, acute nitrate supplementation does not alter extremity rewarming, endothelial function or blood pressure in individuals with cold sensitivity.

[Thoracic lavage and open cardiac massage as treatment of hypothermic cardiac arrest--case report]. / Avoin sydänhieronta ja rintaontelon huuhtelu hypotermisen sydänpysähdyksen hoitona.

Cardiopulmonary bypass is the treatment of choice for a severely hypothermic patient with cardiac arrest. However, the treatment is not always available. We describe a successful three-and-a-half hour resuscitation of a hypothermic cardiac arrest patient with manual chest compressions followed by open cardiac massage and rewarming with thoracic lavage.

Negative effect of combined cysteine and glutathione in soy lecithin-based extender on post-thawed ram spermatozoa.

This study was conducted to evaluate the effect of combined cysteine and glutathione in soy lecithin-based semen extender on post-thawed ram sperm quality. A total of 28 ejaculates were collected twice a week (from four rams) during breeding season. In each replicate, semen samples (n = 4, one ejaculate for each ram) were pooled and divided into three equal parts, and each part was diluted with one of following extender: (1) soy lecithin-based extender containing no cysteine and no glutathione (C0-G0), (2) soy lecithin-based extender containing cysteine (5 mM) and glutathione (5 mM) (C5-G5), and (3) soy lecithin-based extender containing cysteine (10 mM) and glutathione (10 mM) (C10-G10). After freeze-thawing process, motility and velocity parameters, plasma membrane integrity and functionality, mitochondrial activity, and apoptosis features of spermatozoa were evaluated. The obtained results showed that total and progressive motility, plasma membrane integrity and functionality, and live post-thawed spermatozoa was lower in C10-G10 extender compared to C0-G0 and C5-G5 extenders (P < 0.05). Also, the percentage of dead spermatozoa was higher in C10-G10 extender compared to C0-G0 extender (P < 0.05). Apoptotic spermatozoa was lower in C10-G10 extender compared to C0-G0 and C5-G5 extenders (P < 0.05). All velocity parameters, exception of BCF, did not different between extenders (P > 0.05). In conclusion, it seems that high concentration of combined cysteine and glutathione in soy lecithin-based semen extender has a detrimental effect of post-thawed ram sperm quality.

Therapeutic peritoneal lavage with warm saline solution as an option for a critical hypothermic trauma patient.

INTRODUCTION: In this paper, we present the case of a 63-year-old woman, who was found in her flat lying unconscious on the floor for an unknown time. At the time of admission, her core temperature was 24 °C and ventricular fibrillation was detected on the electrocardiogram (ECG). Because of the unstable conditions, the persistent nonperfusing cardiac rhythm and the dramatically inhibited coagulation cascade, a peritoneal lavage connected to a rapid infuser was performed for rewarming, instead of using a transportable heart-lung machine and a haemodialysis device. After a prolonged cardiopulmonary resuscitation (CPR), the patient could be transferred to the intensive care unit (ICU) in a stable condition. After 40 days in the ICU, recovery was fast, and another month of treatment later, she could be discharged back home without any discomfort. CONCLUSION: This report illustrates the successful use of the peritoneal lavage for rewarming a severely hypothermic patient without any extracorporeal rewarming device. Furthermore, it can be used in nearly every hospital if the necessary equipment is affordable. It is demonstrated that this technique is able to provide good outcomes for all victims of accidental hypothermia.

[Air conditioning units and warm air blankets in the operating room]. / Krankenhaushygiene - Raumlufttechnische Anlagen und Warmluftdecken in Operationssälen.

Nowadays almost all operating rooms are equipped with air conditioning (AC units). Their main purpose is climatization, like ventilation, moisturizing, cooling and also the warming of the room in large buildings. In operating rooms they have an additional function in the prevention of infections, especially the avoidance of postoperative wound infections. This is achieved by special filtration systems and by the creation of specific air currents. Since hypothermia is known to be an unambiguous factor for the development of postoperative wound infections, patients are often actively warmed intraoperatively using warm air blankets (forced-air warming units). In such cases it is frequently discussed whether such warm air blankets affect the performance of AC units by changing the air currents or whether, in contrast, have exactly the opposite effect. However, it has been demonstrated in numerous studies that warm air blankets do not have any relevant effect on the functioning of AC units. Also there are no indications that their use increases the rate of postoperative wound infections. By preventing the patient from experiencing hypothermia, the rate of postoperative wound infections can even be decreased thereby.

[Resuscitation of vital activity in intensively cooled animals by physiological methods without rewarming].

White rat males (Wistar) were cooled in the water (9-10 °C) to the stop breathing (at rectal temperature 14.7 ± 0.5°, brain 16.0 ± 0.3 °C). After the removal of water animals were injected 0.5% solution disodium salt ethylenediaminetetraacetic acid (Na2EDTA) intravenously, which reduced the concentration of Ca2+ in the blood. Breathing rats were resumed after 4-8 min after administration Na2EDTA. Then one group of rats was cooled to the temperature of the body 12.2 ± 0.7 (brain 14.9 ± 0.3 °C). At such a low temperatures the breath of rats was long-term (2-3 hours) supported at the level of 12 ± 3 cycle/min. The second group of rats was not additionally cooled after the resumption of breathing. The same dose of Na2EDTA caused the rise of the respiratory rate to a higher level--29 ± 4 cycles/min at a temperature in the rectum and the brain 15-16°. Apparently, the process of accumulation of Ca2+ in the cytoplasm of the respiratory center's cells was slowed after the Na2EDTA injection to hypothermal rats in the bloodstream. It is assumed that the Na2EDTA injection under the hypothermia conditions was activated the cell's protection mechanisms from cold damage. The obtained results and the literature data allowed to conclude that nonhibernators are able to maintain basic life functions under significant reduction in the body temperature.

[Treating frostbite injuries]. / Behandeling van bevriezingsletsels.

Frostbite injuries rarely occur in healthy Dutch persons. However, as the number of people engaging in winter and outdoor activities and travelling to high altitudes increases, the risk of frostbite also increases. Frostbite is a cold-induced injury which results from two processes: freezing and microvascular occlusion. Adequate first aid, which focuses on the prevention of refreezing and mechanical injury, and rapid rewarming together with the administration of ibuprofen, are of the greatest importance for limiting eventual tissue damage. Iloprost infusion and possibly (r)tPA are indicated if a patient presents within 24 hours after the tissue has thawed and the injury is such that severe morbidity can be expected. If the patient presents after this time period, hyperbaric oxygen therapy may be considered; however, the evidence available on this type of treatment is limited.

The effects of active warming on patient temperature and pain after total knee arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) is a procedure with associated risks of inadvertent perioperative hypothermia and significant postoperative pain. Hypothermia may affect patients' experience of postoperative pain, although the link is not well understood. OBJECTIVE: The aim of this prospective, randomized controlled trial was to determine the efficacy of a patient-controlled active warming gown in optimizing patients' perioperative body temperature and in diminishing postoperative pain after TKA. METHODS: Thirty patients who would be undergoing TKA received either a standard hospital gown and prewarmed standard cotton blanket (n = 15) or a patient-controlled, forced-air warming gown (n = 15). RESULTS: Although pain scores were not significantly different in the two groups (P = 0.08), patients who received warming gowns had higher temperatures (P < 0.001) in the postanesthesia care unit, used less opioid (P = 0.05) after surgery, and reported more satisfaction (P = 0.004) with their thermal comfort than did patients who received standard blankets. These findings indicate that patient-controlled, forced-air warming gowns can enhance perioperative body temperature and improve patient satisfaction. Patients who use warming gowns may also need less opioid to manage their postoperative pain. CONCLUSIONS: Nurses should ensure that effective patient warming methods are employed in all patients, particularly in patients with compromised thermoregulatory systems (such as older adults), and in surgeries considered to be exceptionally painful (such as TKA).

Hipotermia accidental / Accidental hypothermia

La hipotermia es un proceso poco frecuente e infradiagnosticado que cada año produce víctimas mortales. Su tratamiento requiere termómetros que midan la temperatura central. En el hospital se usa la sonda esofágica; sobre el terreno y en la hipotermia moderada es suficiente la medición epitimpánica. El tratamiento inicial consiste en soporte vital y recalentamiento. Los movimientos bruscos pueden desencadenar arritmias que no responden a fármacos ni a desfibrilación hasta que se alcanzan los 30°C. El recalentamiento externo pasivo es el método de elección en la hipotermia leve y es un método suplementario en la hipotermia moderada y grave. El recalentamiento externo activo está indicado en la hipotermia moderada o leve refractaria al recalentamiento externo pasivo y como método suplementario en la hipotermia grave. El recalentamiento interno activo está indicado en la hipotermia grave o moderada refractaria al recalentamiento externo activo y en pacientes hemodinámicamente inestables. Los pacientes con hipotermia grave, parada cardiorrespiratoria y potasio inferior a 12mmol/l pueden requerir by-pass cardiopulmonar (AU)

Accidental hypothermia is an infrequent and under-diagnosed pathology, which causes fatalities every year. Its management requires thermometers to measure core temperature. An esophageal probe may be used in a hospital situation, although in moderate hypothermia victims epitympanic measurement is sufficient. Initial management involves advance life support and body rewarming. Vigorous movements can trigger arrhythmia which does not use to respond to medication or defibrillation until the body reaches 30°C. External, passive rewarming is the method of choice for mild hypothermia and a supplementary method for moderate or severe hypothermia. Active external rewarming is indicated for moderate or severe hypothermia or mild hypothermia that has not responded to passive rewarming. Active internal rewarming is indicated for hemodynamically stable patients suffering moderate or severe hypothermia. Patients with severe hypothermia, cardiac arrest or with a potassium level below 12 mmol/l may require cardiopulmonary bypass treatment (AU)