Comparison of prewarming plus intraoperative warming with intraoperative warming alone in patients undergoing minimally invasive thoracic or abdominal surgery: A systematic review and meta-analysis.

OBJECTIVE: Prewarming has been recommended to reduce intraoperative hypothermia. However, the evidence is unclear. This review examined if prewarming can prevent intraoperative hypothermia in patients undergoing thoracoscopic and laparoscopic surgeries. METHODS: PubMed, CENTRAL, Web of Science, and Embase databases were searched for randomized controlled trials (RCTs) up to 15th January 2024. The primary outcome of interest was the difference in intraoperative core temperature. The secondary outcomes were intraoperative hypothermia (<36°) and postoperative shivering. RESULTS: Seven RCTs were eligible. Meta-analysis showed that intraoperative core temperature was significantly higher at the start or within 30mins of the start of the surgery (MD: 0.32 95% CI: 0.15, 0.50 I2 = 94% p = 0.0003), 60 mins after the start of the surgery (MD: 0.37 95% CI: 0.24, 0.50 I2 = 81% p<0.00001), 120 mins after the start of the surgery (MD: 0.34 95% CI: 0.12, 0.56 I2 = 88% p = 0.003), and at the end of the surgery (MD: 0.35 95% CI: 0.25, 0.45 I2 = 61% p<0.00001). The incidence of shivering was also significantly lower in the prewarming group (OR: 0.18 95% CI: 0.08, 0.43 I2 = 0%). Prewarming was also associated with a significant reduction in the risk of hypothermia (OR: 0.20 95% CI: 0.10, 0.41 I2 = 0% p<0.0001). The certainty of the evidence assessed by GRADE was "moderate" for intraoperative core temperatures at all time points and "low" for minimal intraoperative core temperature, shivering, and hypothermia. CONCLUSION: Moderate to low-quality evidence shows that prewarming combined with intraoperative warming, as compared to intraoperative warming alone, can improve intraoperative temperature control and reduce the risk of hypothermia and shivering in patients undergoing thoracoscopic and laparoscopic procedures.

Estimation of the difference between peritoneal microenvironment and core body temperature during laparoscopic surgery - a prospective observational study.

Maintaining patients' temperature during surgery is beneficial since hypothermia has been linked with perioperative complications. Laparoscopic surgery involves the insufflation of carbon dioxide (CO2) into the peritoneal cavity and has become the standard in many surgical indications since it is associated with better and faster recovery. However, the use of cold and dry CO2 insufflation can lead to perioperative hypothermia. We aimed to assess the difference between intraperitoneal and core temperatures during laparoscopic surgery and evaluate the influence of duration and CO2 insufflation volume by fitting a mixed generalized additive model. In this prospective observational single-center cohort trial, we included patients aged over 17 with American Society of Anesthesiology risk scores I to III undergoing laparoscopic surgery. Anesthesia, ventilation, and analgesia followed standard protocols, while patients received active warming using blankets and warmed fluids. Temperature data, CO2 ventilation parameters, and intraabdominal pressure were collected. We recruited 51 patients. The core temperature was maintained above 36 °C and progressively raised toward 37 °C as pneumoperitoneum time passed. In contrast, the intraperitoneal temperature decreased, thus creating a widening difference from 0.4 [25th-75th percentile: 0.2-0.8] °C at the beginning to 2.3 [2.1-2.3] °C after 240 min. Pneumoperitoneum duration and CO2 insufflation volume significantly increased this temperature difference (P < 0.001 for both parameters). Core vs. intraperitoneal temperature difference increased linearly by 0.01 T °C per minute of pneumoperitoneum time up to 120 min and then 0.05 T °C per minute. Each insufflated liter per unit of time, i.e. every 10 min, increased the temperature difference by approximately 0.009 T °C. Our findings highlight the impact of pneumoperitoneum duration and CO2 insufflation volume on the difference between core and intraperitoneal temperatures. Implementing adequate external warming during laparoscopic surgery effectively maintains core temperature despite the use of dry and unwarmed CO2 gases, but peritoneal hypothermia remains a concern, suggesting the importance of further research into regional effects.Trial registration: Clinicaltrials.gov: NCT04294758.

Risk Factors for Perioperative Hypothermia in Pregnant Women undergoing Cesarean Section: A Systematic Review and Meta-Analysis.

AIM: Hypothermia is one of the common complications of cesarean section, which has a serious impact on intraoperative surgical safety and postoperative recovery of pregnant women. Mitigation of the risk factors of hypothermia in pregnant women undergoing cesarean section may reduce the probability of its occurrence and improve the perioperative comfort of pregnant women. Therefore, this study systematically evaluates the influencing factors of hypothermia in patients undergoing cesarean section, aiming to provide references for the prevention of hypothermia in pregnant women undergoing cesarean section. METHODS: A systematic search was conducted across various databases, including PubMed, Cochrane Library, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang, and Chinese Biomedical Literature databases to gather observational studies on the factors affecting hypothermia in pregnant women undergoing cesarean section. The search deadline was January 30, 2024. Two researchers independently screened literature, extracted data, evaluated quality, and crosschecked the outcomes. Meta analysis was conducted using RevMan 5.3 and Stata17.0. RESULTS: Twelve studies were included in this review, all of which were case-control studies conducted from 2014 to 2022, encompassing a total of 5561 pregnant women. The quality of the studies included was average or above. The meta-analysis results showed that body mass index (mean difference (MD) = -1.47; 95% confidence interval (CI) [-2.84, -0.11]; p = 0.03), operating room temperature (odds ratio (OR) = 2.08; 95% CI [1.56, 2.76]; p < 0.00001), anesthesia method (OR = 1.84; 95% CI [1.40, 2.42]; p < 0.0001), fluid loss (MD = 160.09; 95% CI [77.31, 242.87]; p = 0.0002), flushing volume (MD = 66.43; 95% CI [8.46, 124.40]; p = 0.02), and hypothyroidism (OR = 2.29; 95% CI [1.61, 3.27]; p < 0.00001) were risk factors for perioperative hypothermia in pregnant women undergoing cesarean section (p < 0.05). CONCLUSIONS: The occurrence of hypothermia in pregnant women during the perioperative period is influenced by factors such as low body mass index, spinal anesthesia, low operating room temperature, intraoperative fluid loss, large flushing volume, and hypothyroidism.

Association Between Persistent Hypothermia After Cardiopulmonary Bypass in Neonates and Odds of Serious Complications.

IMPORTANCE: Persistent hypothermia after cardiopulmonary bypass (CPB) in neonates with congenital heart defects (CHD) has been historically considered benign despite lack of evidence on its prognostic significance. OBJECTIVES: Examine associations between the magnitude and pattern of unintentional postoperative hypothermia and odds of complications in neonates with CHD undergoing CPB. DESIGN: Retrospective cohort study. SETTING: Single northeastern U.S., urban pediatric quaternary care center with an established cardiac surgery program. PARTICIPANTS: Population-based sample of neonates greater than or equal to 34 weeks gestation undergoing their first CPB between 2015 and 2019. INTERVENTIONS: None. MAIN OUTCOMES AND MEASUREMENTS: Hourly temperature measurements for the first 48 postoperative hours were extracted from inpatient medical records, and clinical characteristics and outcomes were accessed through the local patient registry. Group-based trajectory modeling (GBTM) identified latent temporal temperature trajectories. Associations of trajectories with outcomes were assessed using multivariable binary logistic regression. Outcomes (postoperative complications) were manually adjudicated by experts or were predefined by the patient registry. RESULTS: Four hundred fifty neonates met inclusion criteria. Their mean (sd) gestational age was 38 weeks (1.3), mean (sd) birth weight was 3.19 kilograms (0.55), median (interquartile range) surgical age was 4.7 days (3.3-7.0), 284 of 450 (63%) were male, and 272 of 450 (60%) were White. GBTM identified three distinct curvilinear temperature trajectories: persistent hypothermia (n = 38, 9%), resolving hypothermia (n = 233, 52%), and normothermia (n = 179, 40%). Compared with the normothermic group, those with persistent hypothermia had significantly higher odds of cardiac arrest, actionable arrhythmia, delayed first successful extubation, prolonged cardiac ICU length of stay, very poor weight gain, and 30-day hospital mortality. The persistent hypothermia group was characterized by greater odds of having a lower gestational age, more prevalent neurologic abnormalities, more unplanned reoperations, and a low surgical mortality risk assessment. CONCLUSIONS: Persistent postoperative hypothermia in neonates after CPB is independently associated with having greater odds of complications. Recovery patterns from postoperative hypothermia may be a clinically useful marker to identify patient instability in neonates. Additional research is needed for causal modeling and prospective validation before clinical adoption.

Improvement of temperature surveillance of neonates in low-resource settings by a simple low-cost device: a descriptive study.

INTRODUCTION: Neonatal hypothermia in low-resource settings is prevalent and closely associated with high morbidity and mortality. We examined if an easy-to-read temperature detector device improves health outcomes. METHODS: In a descriptive study, 1009 admissions to a neonatal ward in a tertiary care hospital in Lilongwe, Malawi, were analysed and divided into a baseline and a trial group. The data of 531 newborns with standard care (SC) before the trial were compared with 478 newborns during the implementation of the device (device care=DC). Staff and caregivers were trained on using the device and how to react in case of hypothermia. Data were collected from patient files, device documentation sheets, interviews and focus group discussions. Hypothermia was defined as a body temperature <36.5°C. RESULTS: During the trial, body temperatures throughout the hospital stay were significantly more often obtained (p<0.0001). The median temperature measurements per newborn per day were 1.3 times with SC and 1.6 times with DC, and mild hypothermia was more frequently detected. Moderate hypothermia was avoided in the lightest weight group possibly contributing to significantly shorter hospital stays of surviving newborns (p=0.007). Many caregivers had difficulties using and interpreting the device correctly, and 47% of the reported colours did not match the registered temperatures. Contrary to the above, a questionnaire and focus group discussions with caregivers and health workers showed a high acceptance and the overall opinion that the device was beneficial. CONCLUSION: With more frequent temperature checks, infants with lower birth weight possibly benefited from implementing an easy-to-read continuous temperature indicator, but hypothermia rates remained high. Our data and experiences reveal structural, communicational and consistency/interpretation deficits. Although specifically designed for low-resource settings, the implementation of the device needs a well-working and structured environment, especially regarding staff and caregiver communication.

Biomarker patterns and mechanistic insights into hypothermia from a postmortem metabolomics investigation.

Postmortem metabolomics holds promise for identifying crucial biological markers relevant to death investigations and clinical scenarios. We aimed to assess its applicability in diagnosing hypothermia, a condition lacking definitive biomarkers. Our retrospective analysis involved 1095 postmortem femoral blood samples, including 150 hypothermia cases, 278 matched controls, and 667 randomly selected test cases, analyzed using UHPLC-QTOF mass spectrometry. The model demonstrated robustness with an R2 and Q2 value of 0.73 and 0.68, achieving 94% classification accuracy, 92% sensitivity, and 96% specificity. Discriminative metabolite patterns, including acylcarnitines, stress hormones, and NAD metabolites, along with identified pathways, suggest that metabolomics analysis can be helpful to diagnose fatal hypothermia. Exposure to cold seems to trigger a stress response in the body, increasing cortisol production to maintain core temperature, possibly explaining the observed upregulation of cortisol levels and alterations in metabolic markers related to renal function. In addition, thermogenesis seems to increase metabolism in brown adipose tissue, contributing to changes in nicotinamide metabolism and elevated levels of ketone bodies and acylcarnitines, these findings highlight the effectiveness of UHPLC-QTOF mass spectrometry, multivariate analysis, and pathway identification of postmortem samples in identifying metabolite markers with forensic and clinical significance. The discovered patterns may offer valuable clinical insights and diagnostic markers, emphasizing the broader potential of postmortem metabolomics in understanding critical states or diseases.

A deep learning-based real-time hypothermia and hyperthermia monitoring system with a simple body sensor.

A real-time hypothermia and hyperthermia monitoring system with a simple body sensor based on a Convolutional Neural Network (CNN) is presented. The sensor is produced with 3D-printed thermochromic material. Due to the color change feature of thermochromic materials with temperature, 3D-printed thermochromic Polylactic Acid (PLA) material was used to monitor temperature changes visually. In this paper, we have used the transfer learning technique and fine-tuned the AlexNet CNN. Thirty images for each temperature class between 28-44°C and 510 image data were used in the algorithm. We used 80% and 20% of the data for training and validation. We achieved 96.1% accuracy of validation with a fine-tuned AlexNet CNN. The material's characteristics suggest that it could be employed in delicate temperature sensing and monitoring applications, particularly for hypothermia and hyperthermia.

Severe Hypothermia Induces Ferroptosis in Cerebral Cortical Nerve Cells.

Abnormal shifts in global climate, leading to extreme weather, significantly threaten the safety of individuals involved in outdoor activities. Hypothermia-induced coma or death frequently occurs in clinical and forensic settings. Despite this, the precise mechanism of central nervous system injury due to hypothermia remains unclear, hindering the development of targeted clinical treatments and specific forensic diagnostic indicators. The GEO database was searched to identify datasets related to hypothermia. Post-bioinformatics analyses, DEGs, and ferroptosis-related DEGs (FerrDEGs) were intersected. GSEA was then conducted to elucidate the functions of the Ferr-related genes. Animal experiments conducted in this study demonstrated that hypothermia, compared to the control treatment, can induce significant alterations in iron death-related genes such as PPARG, SCD, ADIPOQ, SAT1, EGR1, and HMOX1 in cerebral cortex nerve cells. These changes lead to iron ion accumulation, lipid peroxidation, and marked expression of iron death-related proteins. The application of the iron death inhibitor Ferrostatin-1 (Fer-1) effectively modulates the expression of these genes, reduces lipid peroxidation, and improves the expression of iron death-related proteins. Severe hypothermia disrupts the metabolism of cerebral cortex nerve cells, causing significant alterations in ferroptosis-related genes. These genetic changes promote ferroptosis through multiple pathways.

Hypothermia and the Global War on Terror: 18 Years of Minimal Progress.

INTRODUCTION: The association between hypothermia, coagulopathy, and acidosis in trauma is well described. Hypothermia mitigation starts in the prehospital setting; however, it is often a secondary focus after other life-saving interventions. The deployed environment further compounds the problem due to prolonged evacuation times in rotary wing aircraft, resource limitations, and competing priorities. This analysis evaluates hypothermia in combat casualties and the relationship to resuscitation strategy with blood products. METHODS: Using the data from the Department of Defense Joint Trauma Registry from 2003 to 2021, a retrospective analysis was conducted on adult trauma patients. Inclusion criteria was arrival at the first military treatment facility (MTF) hypothermic (<95ºF). Study variables included: mortality, year, demographics, battle vs non-battle injury, mechanism, theater of operation, vitals, and labs. Subgroup analysis was performed on severely injured (15 < ISS < 75) hypothermic trauma patients resuscitated with whole blood (WB) vs only component therapy. RESULTS: Of the 69,364 patients included, 908 (1.3%) arrived hypothermic; the vast majority of whom (N = 847, 93.3%) arrived mildly hypothermic (90-94.9°F). Overall mortality rate was 14.8%. Rates of hypothermia varied by year from 0.7% in 2003 to 3.9% in 2014 (P <0.005). On subgroup analysis, mortality rates were similar between patients resuscitated with WB vs only component therapy; though base deficit values were higher in the WB cohort (-10 vs -6, P < 0.001). CONCLUSION: Despite nearly 20 years of combat operations, hypothermia continues to be a challenge in military trauma and is associated with a high mortality rate. Mortality was similar between hypothermic trauma patients resuscitated with WB vs component therapy, despite greater physiologic derangements on arrival in patients who received WB. As the military has the potential to conduct missions in environments where the risk of hypothermia is high, further research into hypothermia mitigation techniques and resuscitation strategies in the deployed setting is warranted.

Intermittent hemodialysis as a rewarming strategy for severe hypothermia in patients without renal failure: a case report.

This case report highlights the effective use of intermittent hemodialysis (IHD) in warming a 71-year-old female patient with severe hypothermia who presented with a rectal temperature of 25 °C and signs of hemodynamic instability. The patient, found unconscious after prolonged exposure to cold exacerbated by alcohol consumption, initially showed some improvement in core temperature through active external rewarming methods. However, soon, her temperature plateaued at 27 °C. Patient was deemed unsuitable for extracorporeal membrane oxygenation (ECMO) or cardiopulmonary bypass (CPB) due to her age, and urgent IHD was initiated. This approach resulted in a stable increase in core temperature at approximately 2.0 °C/hr, along with normalization of lactic acidosis, creatinine phosphokinase, and correction of electrolyte imbalances, culminating in her full recovery and discharge after seven days in the hospital.After reviewing this case alongside similar ones from before, this case report highlights the efficacy and safety of IHD as an efficient, readily available, and less invasive method for rewarming moderate to severe hypothermic patients who are hemodynamically unstable patients but do not have cardiac arrest or renal dysfunction. IHD is especially useful when less invasive cooling devices (Artic Sun/ CoolGard) are not available or more invasive extracorporeal life support options (ECMO/ CPB) are either not indicated or unavailable. IHD can also help improve concurrent electrolyte imbalances and/or toxin buildup. The report further emphasizes the necessity of monitoring for potential complications, such as post-dialysis hypophosphatemia and rebound hyperkalemia, following successful rewarming.

An Implementation Science Study of a Heat-Producing Wrap to Complement KMC in Rwanda.

Background: Neonatal hypothermia is a major cause of preventable morbidity and mortality, especially among the world's poorest newborns. A heat-producing wrap is necessary when kangaroo mother care (KMC) is insufficient or unavailable, yet there is little published research on such wraps. The Dream Warmer is a wrap designed to complement KMC and has been extensively studied in formal research settings but not in real-world conditions. Objectives: We used implementation science methodology to understand the safety, effectiveness, and functionality of the Dream Warmer (hereafter, "Warmer"); its effect on clinical workflows; its interaction with other aspects of care such as KMC; and the Warmer's reception by healthcare providers (HCPs) and parents. Methods: We conducted a prospective, interventional, one-arm, open-label, mixed-methods study in 6 district hospitals and 84 associated health centers in rural Rwanda. Our intervention was the provision of the Warmer and an educational curriculum on thermoregulation. We compared pre and post intervention data using medical records, audits, and surveys. Findings: The Warmer raised no safety concerns. It was used correctly in the vast majority of cases. The mean admission temperature rose from slightly hypothermic (36.41 °C) pre, to euthermic (36.53 °C) post intervention (p = 0.002). Patients achieved a temperature ≥36.5 °C in 86% of uses. In 1% of audits, patients were hyperthermic (37.6-37.9 °C). Both HCPs and parents reported a generally positive experience with the Warmer. HCPs were challenged to prepare it in advance of need. Conclusions: The Warmer functions similarly well in research and real-world conditions. Ongoing education directed toward both HCPs and parents is critical to ensuring the provision of a continuous heat chain. Engaging families in thermoregulation could ease the burden of overtaxed HCPs and improve the skill set of parents. Hypothermia is a preventable condition that must be addressed to optimize neonatal survival and outcome.

Impact of postpartum maternal fever or hypothermia on newborn and early infant illness and death in Southwestern Uganda.

BACKGROUND: Deaths occurring during the neonatal period contribute close to half of under-five mortality rate (U5MR); over 80% of these deaths occur in low- and middle-income countries (LMICs). Poor maternal antepartum and perinatal health predisposes newborns to low birth weight (LBW), birth asphyxia, and infections which increase the newborn's risk of death. METHODS: The objective of the study was to assess the association between abnormal postpartum maternal temperature and early infant outcomes, specifically illness requiring hospitalisation or leading to death between birth and six weeks' age. We prospectively studied a cohort of neonates born at Mbarara Regional Referral Hospital in Uganda to mothers with abnormal postpartum temperature and followed them longitudinally through early infancy. We performed a logistic regression of the relationship between maternal abnormal temperature and six-week infant hospitalization, adjusting for gestational age and 10-minute APGAR score at birth. RESULTS: Of the 648 postpartum participants from the parent study who agreed to enrol their neonates in the sub-study, 100 (15%) mothers had abnormal temperature. The mean maternal age was 24.6 (SD 5.3) years, and the mean parity was 2.3 (SD 1.5). There were more preterm babies born to mothers with abnormal maternal temperature (10%) compared to 1.1% to mothers with normal temperature (p=˂0.001). While the majority of newborns (92%) had a 10-minute APGAR score > 7, 14% of newborns whose mothers had abnormal temperatures had APGAR score ˂7 compared to 7% of those born to mothers with normal postpartum temperatures (P = 0.02). Six-week outcome data was available for 545 women and their infants. In the logistic regression model adjusted for gestational age at birth and 10-minute APGAR score, maternal abnormal temperature was not significantly associated with the composite adverse infant health outcome (being unwell or dead) between birth and six weeks' age (aOR = 0.35, 95% CI 0.07-1.79, P = 0.21). The 10-minute APGAR score was significantly associated with adverse six-week outcome (P < 0.01). CONCLUSIONS: While our results do not demonstrate an association between abnormal maternal temperature and newborn and early infant outcomes, good routine neonate care should be emphasized, and the infants should be observed for any abnormal findings that may warrant further assessment. TARGET JOURNAL: BMC Pregnancy and Childbirth ( https://bmcpregnancychildbirth.biomedcentral.com/ ).

Preventing Hypothermia in Newborns With Congenital Anomalies in the Delivery Room.

BACKGROUND: Thermoregulation interventions in the delivery room have historically focused on preterm infants and studies often exclude term infants or those infants with known congenital anomalies. PURPOSE: The purpose of this quality improvement project was to reduce the rate of admission hypothermia in neonates of all gestational ages born with congenital anomalies and admitted to the intensive care unit (ICU). METHODS: Utilizing the Institute for Healthcare Improvement model for improvement, implementation of plan, do study, act cycles focused on standardizing temperatures of the delivery room and resuscitation bed, recommendations for temperature monitoring, trialing polyethylene lined hats, and implementing a delivery room thermoregulation checklist. RESULTS: Overall, the mean rate of neonates admitted to the ICU hypothermic (<36.5°C) decreased from 27% to 9% over an 8-month period. IMPLICATIONS FOR PRACTICE AND RESEARCH: The interventions significantly reduced the number of neonates admitted to the ICU with hypothermia. Implementation of thermoregulation bundles should apply to all neonates with congenital anomalies to decrease risks associated with hypothermia.

Management and Clinical Outcomes of Neonatal Hypothermia in the Newborn Nursery.

OBJECTIVES: Neonatal hypothermia has been shown to be commonly detected among late preterm and term infants. In preterm and very low birth weight infants, hypothermia is associated with increased morbidity and mortality. Little is known about the clinical interventions and outcomes in hypothermic late preterm and term infants. This study fills this gap in the evidence. METHODS: Single-center retrospective cohort study using electronic health record data on infants ≥35 weeks' gestation admitted to a newborn nursery from 2015 to 2021. Hypothermia was categorized by severity: none, mild (single episode, 36.0-36.4°C), and moderate or recurrent (<36.0°C and/or 2+ episodes lasting at least 2 hours). Bivariable and multivariable logistic regression examined associations between hypothermia and interventions or outcomes. Stratified analyses by effect modifiers were conducted when appropriate. RESULTS: Among 24 009 infants, 1111 had moderate or recurrent hypothermia. These hypothermic infants had higher odds of NICU transfer (adjusted odds ratio [aOR] 2.10, 95% confidence interval [CI] 1.68-2.60), sepsis evaluation (aOR 2.23, 95% CI 1.73-2.84), and antibiotic use (aOR 1.73, 95% CI 1.15-2.50) than infants without hypothermia. No infants with hypothermia had culture-positive sepsis, and receipt of antibiotics ≥72 hours (surrogate for culture-negative sepsis and/or higher severity of illness) was not more common in hypothermic infants. Hypothermic infants also had higher odds of blood glucose measurement and hypoglycemia, slightly higher percent weight loss, and longer lengths of stay. CONCLUSIONS: Late preterm and term infants with hypothermia in the nursery have potentially unnecessary increased resource utilization. Evidence-based and value-driven approaches to hypothermia in this population are needed.

Prevention of NICU Admission Hypothermia in Moderate- and Late-Preterm Infants.

BACKGROUND: Neonatal hypothermia is a common and preventable cause of neonatal morbidity and mortality. Although hypothermia prevention has been extensively studied in infants <32 weeks' gestation, the authors of few studies have targeted moderate- and late-preterm infants (MLPIs) in the delivery room. METHODS: This quality improvement initiative was conducted from June 2019 to June 2023 at the Massachusetts General Hospital NICU and Labor and Delivery Unit. All inborn MLPIs 32 + 0/7 to 36 + 6/7 weeks' gestation admitted to the NICU were included. We expanded thermoregulatory measures typically used in protocols for infants <32 weeks' gestation, including increasing delivery room ambient temperature to 74°F and thermal mattress use. The primary outcome was hypothermia (<36.5°C) after NICU admission. The balancing measure was hyperthermia (≥38 °C). RESULTS: During the study period, there were 566 inborn MLPIs with a mean gestational age of 34 + 3/7 weeks and a mean birth weight of 2269 g. Special cause variation in neonatal hypothermia incidence was observed with a decrease from a mean baseline of 27% to 7.8% postintervention. Special cause variation was observed in hyperthermia incidence, with an increase from 1.4% to 6.2% postintervention largely initially associated with noncompliance with the protocol for thermal mattress removal. CONCLUSIONS: The expansion of several thermoregulation techniques commonly used in infants <32 weeks' gestation, particularly thermal mattress use, was associated with a decreased incidence of NICU admission hypothermia in MLPIs, with an increase in mild hyperthermia predominantly associated with concomitant polyethylene wrap use.

An unusual cause of neonatal hypothermia and shock in the emergency department: Diamond Blackfan Anemia.

Diamond Blackfan Anemia (DBA) is a rare disease characterized by anemia secondary to impaired red blood cell production from bone marrow failure. We present a case of infantile hypothermia and shock caused by this clinical pathology. A seven-week-old infant was brought to the emergency department by the father with the chief complaint of abnormal breathing and low activity level throughout the day. Medical history was unremarkable for both the patient and the family. On examination, the infant was breathing 30 breaths per minutes, had a heart rate of 116, and a core temperature of 33 degrees Celsius. The infant was ashen in color, limp, with grunted breathing and minimal movement. Numerous abnormal laboratory readings were reported, with the most significant being a hemoglobin of 1.7 and a hematocrit of 7.4. Emergent blood transfusion was initiated, and the patient was eventually air-lifted to a pediatric hospital two hours away. This case highlights the imperative of a thorough history and examination and consideration of a broad differential for neonatal hypothermia and shock, especially in the setting of no obvious bleeding.

A critically prolonged avalanche burial with recorded cardiac electrical activity and complete recovery - a case report.

The probability of survival in avalanche accidents is time-dependent. Critically buried victims who undergo a long burial duration (over 60 min) face a possible mortality rate of over 80%. Understanding the physiological response during critical avalanche burial is crucial for improving rescue strategies and outcomes. We present the case of a 55-year-old male skier buried under an avalanche for 4 h and 51 min in the Italian Alps. Continuous heart rate monitoring revealed distinct phases of cardiac activity during burial. Despite severe hypothermia, the victim survived without extracorporeal rewarming. This case highlights the importance of continuous monitoring and appropriate on-site management in avalanche accidents. Factors such as the presence of an air pocket may positively influence survival. This case underscores the importance of comprehensive resuscitative measures and guidelines for managing avalanche victims with prolonged burial durations.

Human CYP2D6 varies across the estrous cycle in brains of transgenic mice altering drug response.

Cytochrome P450 (CYP) 2Ds are drug metabolizing enzymes found in brain and liver which metabolize numerous centrally acting drugs. Inhibition and induction of CYP2D-mediated metabolism in rodent brain alters brain drug and metabolite concentrations and resulting drug response. In female rats, brain CYP2D metabolism varies across the estrous cycle and with exogenous estrogen, changing brain drug concentrations and response. In this study harmine-induced hypothermia was lower in humanized CYP2D6 transgenic female mice during estrus compared to diestrus. Pretreatment into the cerebral ventricles with propranolol, a selective irreversible inhibitor of human CYP2D6 in brain, increased hypothermia in estrus but not in diestrus. In vivo enzyme activity was higher in brains of transgenic mice in estrus compared to diestrus and was lower after pretreatment with inhibitor in estrus, but not in diestrus. Hepatic activity and plasma harmine concentrations were unaffected by either estrous phase or inhibition of brain CYP2D6. In wild-type female mice, harmine-induced hypothermia was unaffected by either estrous phase or inhibitor pretreatment. Male mice were used as positive controls, where pretreatment with inhibitor increased harmine-induced hypothermia in transgenic but not wild-type, mice. This study provides evidence for female hormone cycle-based regulation of drug metabolism by human CYP2D6 in brain and resulting drug response. This suggests that brain CYP2D6 metabolism may vary, for example, during the menstrual cycle, pregnancy, or menopause, or while taking oral contraceptives or hormone therapy. This variation could contribute to individual differences in response to centrally acting CYP2D6-substrate drugs by altering local brain drug and/or metabolite concentrations.