Therapeutic hypothermia and temperature management最新文献

This study aimed to determine the effects of preoperative active and passive warming on postoperative hypothermia, vital signs, and perception of thermal comfort in patients scheduled to undergo elective open abdominal surgery. This was a randomized controlled study. The study sample comprised 90 patients (30 in the active warming group, 30 in the passive warming group, and 30 in the control group) who agreed to participate and met the research criteria. According to the comparison of patients' vital signs, a statistically significant difference was observed in terms of patients' preoperative body temperature values (χ² = 56.959; p = 0.000). A comparison of the patients' postoperative thermal comfort perception scores yielded a statistically significant difference (χ² = 39.693; p = 0.000). Postoperative comfort scores in the active warming group were significantly higher than those in the passive warming and control groups. In conclusion, warming methods are effective in preventing undesirable postoperative hypothermia. The time to reach normothermia after surgery was shorter, vital signs were at a desirable level, and thermal comfort perceptions were higher in patients who were prewarmed. ClinicalTrials.gov (Identifier: NCT04997694).

Women undergoing breast surgery seem to be under the risk for hypothermia (central body temperature <36°) due to the uncertainty caused by the preoperative preparation time and the variety of operations, leading to neglect of warming precautions. The study examines the perioperative hypothermia (PH) in breast surgery and the relationships between the depth of decrease in body temperature and individual or clinical variables. This prospective, cross-sectional, observational study includes 120 female patients 18-65 years of age who were given general anesthesia for breast surgery. The incidence of hypothermia was 68.1%. The given patients were discriminated as body temperature <36°, hypothermia was significantly related with lower weight, body mass index, American Society of Anesthesiology (ASA) score, baseline body temperatures, higher extubation, and recovery times. When patients' temperature decreases by >1 or 1.5°, lower age and longer durations of operation and anesthesia were also significant variables. The incidence of shivering is quite high at temperatures below 36°C or at 1 and 1.5°C reductions from baseline (72.7%, 84%, 94.1%, respectively). Body temperature changes of the patients had no effect on nausea-vomiting and pain scores. It turned out that the incidence of PH and shivering is high in women who underwent breast surgery. We think that the depth of decrease in body temperature should be taken into account when evaluating the predictors or clinical consequences of hypothermia, except for the 36°C limit for body temperature.

Malignant hyperthermia (MH) is a rare, life-threatening condition caused by alterations in skeletal muscle calcium channels inherited through an autosomal dominant pattern. The use of specific agents in anesthesia such as inhaled anesthetics and succinylcholine can precipitate a hyperthermic crisis. Patients experience a rapid increase in muscle rigidity, secondary to skeletal muscle calcium dysregulation, leading to acute rhabdomyolysis and possible hyperthermia. Providers must have a high index of suspicion of this disease process because early diagnosis is critical to mortality reduction. Management centers around removal of the offending agent, dantrolene, and supportive care including cooling if hyperthermic. Intravascular cooling devices have been used in thermodynamic regulation after cardiac arrest and have shown to be more effective than dermal cooling techniques; however, they have not been well described in other disease processes. The following case report is the first to describe a patient suffering from MH to undergo invasive intravenous cooling in order to counteract the effects of this life-threatening disease.

Asphyxiated newborns often require both therapeutic hypothermia (TH) and mechanical ventilation (MV) and the complex interrelationship between these two therapeutic interventions is very interesting, which could not only have several synergistic positive effects but also some risks. Perinatal asphyxia is the leading cause of neonatal hypoxic-ischemic encephalopathy (HIE) and TH is the only approved neuroprotective treatment to limit brain injury, improving the mortality rate and long-term neurological outcomes. HIE is often associated with severe respiratory failure, requiring MV, due to different lung diseases or an impairment of the respiratory drive. The respiratory support management of asphyxiated newborns is very difficult, considering (a) various pathophysiological contexts, (b) the strong impact of TH on gas metabolism and (c) on lung mechanics, and (d) complex TH-MV interactions. Therefore, it is necessary to evaluate the real indications of MV for cooled newborns, considering the risks of respiratory overassistance (hypocapnia/hyperoxia), as well as the adequate monitoring systems. To date, specific randomized studies about the optimal respiratory approach for cooled newborns are lacking, and strategies for MV support vary from center to center. Moreover, there are many open questions about the real effects of cooling on lung mechanics and on surfactant, most appropriate method of blood gas analysis, and clear indications for pharmacological sedation. The aim of this review is to propose a reasoned approach for respiratory management of cooled newborns, considering the pathophysiological context, multiple actions of TH, and consequences of TH-MV matched action and its related risks.

Although most commonly associated with infection, elevated temperature and fever also occur in a variety of critically ill populations. Prior studies have suggested that fever and elevated temperature may be detrimental to critically ill patients and can lead to poor outcomes, but the evidence surrounding the association of fever with outcomes is rapidly evolving. To broadly assess potential associations of elevated temperature and fever with outcomes in critically ill adult patients, we performed a systematic literature review focusing on traumatic brain injury, stroke (ischemic and hemorrhagic), cardiac arrest, sepsis, and general intensive care unit (ICU) patients. Searches were conducted in Embase^® and PubMed^® from 2016 to 2021, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, including dual-screening of abstracts, full texts, and extracted data. In total, 60 studies assessing traumatic brain injury and stroke (24), cardiac arrest (8), sepsis (22), and general ICU (6) patients were included. Mortality, functional, or neurological status and length of stay were the most frequently reported outcomes. Elevated temperature and fever were associated with poor clinical outcomes in patients with traumatic brain injury, stroke, and cardiac arrest but not in patients with sepsis. Although a causal relationship between elevated temperature and poor outcomes cannot be definitively established, the association observed in this systematic literature review supports the concept that management of elevated temperature may factor in avoidance of detrimental outcomes in multiple critically ill populations. The analysis also highlights gaps in our understanding of fever and elevated temperature in critically ill adult patients.

Glioblastoma (GBM) is the most commonly occurring of all malignant central nervous system (CNS) tumors in adults. Considering the low median survival of only ∼15 months and poor prognosis in GBM patients, despite surgical resection with adjuvant radiation and chemotherapy, it is vital to seek brand new and innovative treatment in combination with already existing methods. Hypothermia participates in many metabolic pathways, inflammatory responses, and apoptotic processes, while also promoting the integrity of neurons. Following the successful application of therapeutic hypothermia across a spectrum of disorders such as traumatic CNS injury, cardiac arrest, and epilepsy, several clinical trials have set to evaluate the potency of hypothermia in treating a variety of cancers, including breast and ovaries cancer. In regard to primary neoplasms and more specifically, GBM, hypothermia has recently shown promising results as an auxiliary treatment, reinforcing chemotherapy's efficacy. In this review, we discuss the recent advances in utilizing hypothermia as treatment for GBM and other cancers.

The study subject was a healthy, 47-year-old man, a low temperature Guinness World Record holder. He spent 50 days alone in Rovaniemi, Lapland, and functioned in the ambient temperature ranging from +2°C to -37°C. He did not use sources of heat, he did not eat warm meals or drink hot water, and did not dry his clothes. He slept in an igloo, on an ice cover of 20-30 cm. He spent 10 hours a day in a sleeping bag and for the remaining time he walked, skied, or rode a bicycle, and practiced swimming. The aim of the study was a laboratory assessment of renal capacity in a man exposed to long-term extremely low ambient temperatures. The study was approved by the Ethical Committee at the Regional Medical Chamber in Krakow, Poland (approval No.: 194/KBL/OIL/2019). Twice during the observation, urine and blood were collected and analyzed: before and after the prolonged exposure to extremely low ambient temperatures. Changes were seen in many blood and urine parameters, but in urine, they were more significant. In urine, decreased values of sodium (by 53.9%), potassium (by 22.6%), creatinine (by 65.5%), urea (by 61.3%), uric acid (by 58.4%), and protein (by 50%) were observed. Neutrophil gelatinase-associated lipocalin (NGAL) increased by 34%. Absence of calcium oxalate excretion was reported relative to the value before the exposure to cold. In blood, increased values of interleukin-6 (by 60%) and β-2-microglobulin (by 26.9%) were observed. Erythropoietin decreased by 22.4%. No changes were noted in estimated glomerular filtration rate. The study subject lost 10 kg in weight. On the basis of the results obtained during the observation, it can be determined that the probable cause of changes in the laboratory results of the subject was the diet used, and not a dysfunction of the excretory system. The body weight loss and activation of compensating mechanisms focused on saving vitally important diet components, caused by the insufficient diet, exclude the theory of a negative effect of exposure to extremely low temperatures on renal filtration function.

Hypothermia has multiple physiological effects, including decreasing metabolic rate and oxygen consumption (VO₂). There are few human data about the magnitude of change in VO₂ with decreases in core temperature. We aimed to quantify to magnitude of reduction in resting VO₂ as we reduced core temperature in lightly sedated healthy individuals. After informed consent and physical screening, we cooled participants by rapidly infusing 20 mL/kg of cold (4°C) saline intravenously and placing surface cooling pads on the torso. We attempted to suppress shivering using a 1 mcg/kg intravenous bolus of dexmedetomidine followed by titrated infusion at 1.0 to 1.5 μg/(kg·h). We measured resting metabolic rate VO₂ through indirect calorimetry at baseline (37°C) and at 36°C, 35°C, 34°C, and 33°C. Nine participants had mean age 30 (standard deviation 10) years and 7 (78%) were male. Baseline VO₂ was 3.36 mL/(kg·min) (interquartile range 2.98-3.76) mL/(kg·min). VO₂ was associated with core temperature and declined with each degree decrease in core temperature, unless shivering occurred. Over the entire range from 37°C to 33°C, median VO₂ declined 0.7 mL/(kg·min) (20.8%) in the absence of shivering. The largest average decrease in VO₂ per degree Celsius was by 0.46 mL/(kg·min) (13.7%) and occurred between 37°C and 36°C in the absence of shivering. After a participant developed shivering, core body temperature did not decrease further, and VO₂ increased. In lightly sedated humans, metabolic rate decreases around 5.2% for each 1°C decrease in core temperature from 37°C to 33°C. Because the largest decrease in metabolic rate occurs between 37°C and 36°C, subclinical shivering or other homeostatic reflexes may be present at lower temperatures.

Continuous renal replacement therapy (CRRT) is a commonly used therapeutic modality in the pediatric intensive care unit (PICU) for the treatment of severe acute kidney injury, as well as for addressing metabolic abnormalities, fluid-electrolyte imbalances, and acid-base disorders. According to reports, therapeutic hypothermia treatment has demonstrated the ability to decrease cellular metabolism, oxygen consumption, formation of free radicals, cell death, and inflammatory signals. The study encompassed all individuals who underwent CRRT at both Manisa City Hospital and Manisa Celal Bayar University Hospital throughout the period from February 2021 to November 2022. A total of 14 patients who received CRRT were subjected to a warming procedure utilizing an external blanket and an external heater attached to the CRRT venous return line, resulting in the attainment of a body temperature exceeding 36°C. Therapeutic hypothermia was implemented on 12 patients to maintain their body temperature within the range of 32-35°C. The study population exhibited a median age of 24.5 months, with males comprising 61.5% of the sample. A therapeutic hypothermia treatment was administered to a cohort of 12 patients. The patients who had therapeutic hypothermia exhibited a significantly reduced vasoactive-inotropic score (p = 0.038). Patients who did not receive therapeutic hypothermia exhibited a prolonged need for mechanical ventilation (p = 0.020). The duration of stay in the PICU for patients who underwent therapeutic hypothermia was shown to be considerably shorter compared to those who did not receive therapeutic hypothermia (p = 0.047). The potential efficacy of moderate therapeutic hypothermia appears promising, particularly in the context of patients who are receiving CRRT for severe sepsis and acute respiratory distress syndrome. This is attributed to the anti-inflammatory properties and hypometabolic effects associated with this intervention. To the best of our current understanding, this study represents the initial investigation showcasing the effectiveness of combining therapeutic hypothermia with CRRT in the pediatric population.

Therapeutic hypothermia (TH) mitigates damage in ischemic stroke models. However, safer and easier TH methods (e.g., pharmacological) are needed to circumvent physical cooling complications. This study evaluated systemic and pharmacologically induced TH using the adenosine A₁ receptor agonist, N₆-cyclohexyladenosine (CHA), with control groups in male Sprague-Dawley rats. CHA was administered intraperitoneally 10 minutes following a 2-hour intraluminal middle cerebral artery occlusion. We used a 1.5 mg/kg induction dose, followed by three 1.0 mg/kg doses every 6 hours for a total of 4 doses, causing 20-24 hours of hypothermia. Animals assigned to physical hypothermia and CHA-hypothermia had similar induction rates and nadir temperatures, but forced cooling lasted ∼6 hours longer compared with CHA-treated animals. The divergence is likely attributable to individual differences in CHA metabolism, which led to varied durations at nadir, whereas physical hypothermia was better regulated. Physical hypothermia significantly reduced infarction (primary endpoint) on day 7 (mean reduction of 36.8 mm³ or 39% reduction; p = 0.021 vs. normothermic animals; Cohen's d = 0.75), whereas CHA-induced hypothermia did not (p = 0.33). Similarly, physical cooling improved neurological function (physical hypothermia median = 0, physical normothermia median = 2; p = 0.008) and CHA-induced cooling did not (p > 0.99). Our findings demonstrate that forced cooling was neuroprotective compared with controls, but prolonged CHA-induced cooling was not neuroprotective.