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.

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.

[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.

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.

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)

[Accidental hypothermia]. / Hipotermia accidental.

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.

Processed aconite root prevents cold-stress-induced hypothermia and immuno-suppression in mice.

Processed aconite root (PA) is a crude drug used in traditional Chinese or Japanese medicine to generate heat in interior body and dispel cold. We evaluated the effects of PA on hypothermia and reduction in the activity of natural killer (NK) cells in mice exposed to chronic cold stress. Male mice were reared at 4 degrees C, and powdered PA was administered for 10 d as a food additive. Core body temperature of mice significantly decreased by approximately 1 degrees C after rearing in a cold environment, and PA administration significantly restored the reduction in core body temperature in a dose-dependent manner. After 10 d, splenic NK-cell activity of cold-stressed mice was significantly reduced, and the reduction was dose-dependently recovered by PA administration. An aconitine-type alkaloid fraction prepared from PA was ineffective when administered to cold-stressed mice, and the thermogenic effect on hypothermic mice was present in the fraction containing low-molecular-weight compounds without alkaloids. In cold-stressed mice, the weight of brown adipose tissue (BAT) and uncoupling protein (UCP)-1 level in BAT increased, whereas the weight of white adipose tissue decreased. The increase in UCP-1 level in BAT of cold-stressed mice was further augmented by PA treatment. These results indicate that PA exhibited a thermogenic effect on hypothermia induced by cold stress in mice by additional upregulation of UCP-1 level in BAT, which was already enhanced by hypothermia, and that the active ingredients present in PA are non-alkaloidal low-molecular-weight compounds.

Practical implementation of therapeutic hypothermia after cardiac arrest.

INTRODUCTION: Survival after out-of-hospital cardiac arrest (OHCA) remains unacceptably low. Therapeutic hypothermia (TH) is the most efficacious treatment option available for comatose survivors of cardiac arrest. However, clearly delineated instructions for how to induce, maintain, and conclude TH have not been published in a codified format. OBJECTIVE: We assembled 11 clinicians from the University of Pennsylvania Schools of Medicine and Nursing for a day-long moderated discussion to review our institution's TH protocol and reach consensus on a step-by-step management plan of the comatose survivor of OHCA. We attempted to systematically work our way through the existing University of Pennsylvania TH protocol. The goal was to address critical decisions at each stage of care of the post-arrest patient, including whom to cool, how to cool, how long to cool, how to rewarm, neuroprognostication, and other fundamental aspects of patient management. We made every effort to include relevant scientific evidence with appropriate citations. However, given the paucity of data in certain areas, we have relied heavily on expert opinion. SUMMARY: We present a step-by-step management plan for incorporation of TH in the care of the comatose survivor of OHCA, which can be adapted to a variety of clinical settings with diverse resources. This article is intended to supplement current care provided by health care providers and should be adopted in concert with current standards of post-arrest and intensive care unit care.

New circulating-water devices warm more quickly than forced-air in volunteers.

BACKGROUND: Newer circulating-water systems supply more heat than forced-air, mainly because the heat capacity of water is much greater than for that of dry warm air and, in part, because they provide posterior as well as anterior heating. Several heating systems are available, but three major ones have yet to be compared directly. We therefore compared two circulating-water systems with a forced-air system during simulation of upper abdominal or chest surgery in volunteers. METHODS: Seven healthy volunteers participated on three separate study days. Each day, they were anesthetized and cooled to a core temperature near 34 degrees C, which was maintained for 45-60 min. They were then rewarmed with one of three warming systems until distal esophageal core temperature reached 36 degrees C or anesthesia had lasted 8 h. The warming systems were 1) energy transfer pads (two split torso pads and two universal pads; Kimberly Clark, Roswell, GA); 2) circulating-water garment (Allon MTRE 3365 for cardiac surgery, Akiva, Israel); and 3) lower body forced-air warming (Bair Hugger #525, #750 blower, Eden Prairie, MN). Data are presented as mean +/- sd; P < 0.05 was statistically significant. RESULTS: The rate of increase of core temperature from 34 degrees C to 36 degrees C was 1.2 degrees C +/- 0.2 degrees C/h with the Kimberly Clark system, 0.9 degrees C +/- 0.2 degrees C/h with the Allon system, and 0.6 degrees C +/- 0.1 degrees C/h with the Bair Hugger (P = 0.002). CONCLUSIONS: The warming rate with the Kimberly Clark system was 25% faster than with the Allon system and twice as fast as with the Bair Hugger. Both circulating-water systems thus warmed hypothermic volunteers in significantly less time than the forced-air system.

[Comparative evaluation of different methods for normalizing heat state of persons exposed to cold water]. / Sravnitel'naia otsenka razlichnykh sposobov normalizatsii teplovogo sostoianiia cheloveka posle okhlazheniia ego v vodnoi srede.

Decrease of deep body temperature in humans due to exposure to cold water continues after the exposure ends and carries major danger for human health and life. The article covers data characterizing human heat state parameters after rejection of cold (10 +/- 1 degree C) water environment. This rejection was proved to take place in more severely decreased "core" and "capsule" temperature vs that in air environment. Studies of heat state in 38 volunteers practicing winter swimming demonstrated comparative evaluation of various heating methods among which the most effective are immersion into warm (38 degrees C) water with simultaneous hydromassage and being in sauna at air temperature of 65 +/- 5 degrees C.

Effectiveness of a circulating-water warming garment in rewarming after pediatric cardiac surgery using hypothermic cardiopulmonary bypass.

OBJECTIVE: To evaluate the effectiveness and safety of the ALLON 2001 microprocessor-based thermoregulation system in pediatric patients undergoing cardiac surgery requiring hypothermic cardiopulmonary bypass compared with the routine thermal care. DESIGN: Prospective randomized clinical study. SETTING: Single tertiary academic medical center. PARTICIPANTS: Infants (0-1 year) who underwent congenital heart surgery requiring hypothermic cardiopulmonary bypass (n = 18). Patients with open wounds and/or patients treated with an investigational drug or device within 30 days of surgery were excluded. INTERVENTIONS: Randomized use of thermoregulation system (warming garment, n = 9) or routine thermal care (control, n = 9) after separating from cardiopulmonary bypass until the arrival to the pediatric intensive care unit (PICU). MEASUREMENTS AND MAIN RESULTS: There were no statistically significant differences in the demographic data, cardiopulmonary bypass time, operating room time, incidence of deep hypothermic circulatory arrest, and cooling temperature between the groups. The nasopharyngeal temperature was significantly higher in the warming garment group after separation from cardiopulmonary bypass. Nasopharyngeal temperature at 20 minutes was 36.5 degrees C versus 35.01 degrees C (p = 0.0047), at 40 minutes was 36.98 degrees C versus 35.30 degrees C (p = 0.034), and at admission to the PICU was 36.09 degrees C versus 35.31 degrees C (p = not significant). There was no difference in the core-to-peripheral temperature gradient (nasopharyngeal-to-skin temperature) between the 2 study groups at any time point. No adverse events related to the use of the warming garment thermoregulation system were observed. CONCLUSION: The investigated thermoregulation system was effective in preventing the after-drop of temperature that occurs after cardiopulmonary bypass in small infants compared with routine warming methods.

Effects of a circulating-water garment and forced-air warming on body heat content and core temperature.

BACKGROUND: Forced-air warming is sometimes unable to maintain perioperative normothermia. Therefore, the authors compared heat transfer, regional heat distribution, and core rewarming of forced-air warming with a novel circulating-water garment. METHODS: Nine volunteers were each evaluated on two randomly ordered study days. They were anesthetized and cooled to a core temperature near 34 degrees C. The volunteers were subsequently warmed for 2.5 h with either a circulating-water garment or a forced-air cover. Overall, heat balance was determined from the difference between cutaneous heat loss (thermal flux transducers) and metabolic heat production (oxygen consumption). Average arm and leg (peripheral) tissue temperatures were determined from 18 intramuscular needle thermocouples, 15 skin thermal flux transducers, and "deep" hand and foot thermometers. RESULTS: Heat production (approximately 60 kcal/h) and loss (approximately 45 kcal/h) were similar with each treatment before warming. The increases in heat transfer across anterior portions of the skin surface were similar with each warming system (approximately 65 kcal/h). Forced-air warming had no effect on posterior heat transfer, whereas circulating-water transferred 21+/-9 kcal/h through the posterior skin surface after a half hour of warming. Over 2.5 h, circulating water thus increased body heat content 56% more than forced air. Core temperatures thus increased faster than with circulating water than forced air, especially during the first hour, with the result that core temperature was 1.1 degrees +/- 0.7 degrees C greater after 2.5 h (P < 0.001). Peripheral tissue heat content increased twice as much as core heat content with each device, but the core-to-peripheral tissue temperature gradient remained positive throughout the study. CONCLUSIONS: The circulating-water system transferred more heat than forced air, with the difference resulting largely from posterior heating. Circulating water rewarmed patients 0.4 degrees C/h faster than forced air. A substantial peripheral-to-core tissue temperature gradient with each device indicated that peripheral tissues insulated the core, thus slowing heat transfer.

Cryopreservation of garlic shoot tips by vitrification: effects of dehydration, rewarming, unloading and regrowth conditions.

This paper investigates the effect of dehydration, rewarming, unloading and regrowth conditions and of bulb post-harvest storage duration on survival and regeneration of cryopreserved garlic shoot tips. PVS3 was the most effective of the seven vitrification solutions compared. Treating shoot tips with PVS3 for 150-180 min ensured 92 % regeneration after freezing. An air-drying treatment, performed either before or after the PVS3 treatment, was detrimental to regeneration of cryopreserved shoot tips. Rapid rewarming in a water-bath at 37 degree C gave higher regeneration than the slower rewarming procedures employed. Regeneration was similar using either sucrose or sorbitol unloading solutions. The growth regulator content of the recovery medium did not influence percentage regeneration. However, the fresh weight of explants cultured on medium containing 0.3 mg/L zeatin and 0.3 mg/L gibberellic acid was significantly higher than on other media. Post-harvest storage duration of bulbs dramatically influenced survival and regeneration of non-cryopreserved and cryopreserved shoot tips, which were nil for samples cryopreserved immediately after harvest and highest after 3 and 6 months of storage. The optimized cryopreservation protocol was applied to ten different garlic varieties, with regeneration percentages ranging between 72 and 95 %.

Numerical study on three-region thawing problem during cryosurgical re-warming.

Knowledge of the temperature transients of biological bodies during cryosurgical re-warming is critical for the survival of healthy tissues. To better understand the mechanisms thus involved, a one-dimensional numerical algorithm based on finite difference method was applied to simultaneously solve the thawing processes occurring in three regions with one thawing, another blood-perfused and the third frozen one sandwiched between them. Two typical surface heatings with heating plate or convective warm water and a spatial heating using microwave were particularly adopted to investigate the advancement of the two phase-change interfaces and the transient temperature field over the tissue. Differences among these results were compared and their implementation for the cryosurgical re-warming were discussed. Parametric studies were performed to explore influences of the blood perfusion, the microwave heating power, the surface heat convection coefficient, and the surface heating temperature to the thermal history of the biological bodies. Taking account of several typical blood re-flow patterns most probably occurred in the originally frozen and then thawed tissues after the two phase change interfaces meet together, four heat transfer equations were proposed to characterize the re-warming behavior of the biological body. Effect of the non-ideal solution property of the living tissues to the transient temperature field during cryo-surgical re-warming was also tested through introducing a simple however intuitive way.