Observation of the effect of hypothermia therapy combined with optimized nursing on brain protection after cardiopulmonary resuscitation: A retrospective case-control study.

This study aimed to investigate the impact of optimized emergency nursing in conjunction with mild hypothermia nursing on neurological prognosis, hemodynamics, and complications in patients with cardiac arrest. A retrospective analysis was conducted on the medical records of 124 patients who received successful cardiopulmonary resuscitation (CPR) at Fujian Provincial Hospital South Branch. The patients were divided into control and observation groups, each consisting of 62 cases. The brain function of both groups was assessed using the Glasgow Coma Scale and the National Institutes of Health Stroke Scale. Additionally, serum neuron-specific enolase level was measured in both groups. The vital signs and hemodynamics of both groups were analyzed, and the complications and satisfaction experienced by the 2 groups were compared. The experimental group exhibited significantly improved neurological function than the control group (P < .05). Furthermore, the heart rate in the experimental group was significantly lower than the control group (P < .05). However, no significant differences were observed in blood oxygen saturation, mean arterial pressure, central venous pressure, and systolic blood pressure between the 2 groups (P > 0.05). Moreover, the implementation of optimized nursing practices significantly reduced complications and improved the quality of life and satisfaction of post-CPR patients (P < .05). The integration of optimized emergency nursing practices in conjunction with CPR improves neurological outcomes in patients with cardiac arrest.

Incidence and Risk Factors for Postoperative Visual Loss after Cardiac Surgical Procedures: A Systematic Review.

ABSTRACT: Postoperative visual loss (POVL) is an infrequent yet consequential complication that can follow cardiac surgical interventions. This systematic review aims to provide a comprehensive analysis of the incidence of POVL after cardiac surgery and to delineate the associated risk factors. A comprehensive search was conducted in major medical databases for relevant studies published up to September 2022. Eligible studies reporting on the incidence of POVL and identifying risk factors in patients undergoing cardiac surgery were included. Data extraction was performed independently by two reviewers. The pooled incidence rates and the identified risk factors were synthesized qualitatively. POVL after cardiac surgery has an overall incidence of 0.015%, that is, 15 cases per 100,000 cardiac surgical procedures. Risk factors for POVL include patient characteristics (advanced age, diabetes, hypertension, and preexisting ocular conditions), procedural factors (prolonged surgery duration, cardiopulmonary bypass time, and aortic cross-clamping), anesthetic considerations (hypotension, blood pressure fluctuations, and specific techniques), and postoperative complications (stroke, hypotension, and systemic hypoperfusion). Ischemic optic neuropathy (ION) is an uncommon complication, associated with factors like prolonged cardiopulmonary bypass, low hematocrit levels, excessive body weight gain, specific medications, hypothermia, anemia, raised intraocular pressure, and micro-embolization. Diabetic patients with severe postoperative anemia are at increased risk for anterior ischemic optic neuropathy (AION). Posterior ischemic optic neuropathy (PION) can occur with factors like hypertension, postoperative edema, prolonged mechanical ventilation, micro-embolization, inflammation, hemodilution, and hypothermia.While the overall incidence of POVL postcardiac surgery remains modest, its potential impact is substantial, necessitating meticulous consideration of modifiable risk factors. Notably, prolonged surgical duration, intraoperative hypotension, anemia, and reduced hematocrit levels remain salient contributors. Vigilance is indispensable to promptly detect this infrequent yet visually debilitating phenomenon in the context of postcardiac surgical care.

Increasing Knockin Efficiency in Mouse Zygotes by Transient Hypothermia.

Integration of a point mutation to correct or edit a gene requires the repair of the CRISPR-Cas9-induced double-strand break by homology-directed repair (HDR). This repair pathway is more active in late S and G2 phases of the cell cycle, whereas the competing pathway of nonhomologous end-joining (NHEJ) operates throughout the cell cycle. Accordingly, modulation of the cell cycle by chemical perturbation or simply by the timing of gene editing to shift the editing toward the S/G2 phase has been shown to increase HDR rates. Using a traffic light reporter in mouse embryonic stem cells and a fluorescence conversion reporter in human-induced pluripotent stem cells, we confirm that a transient cold shock leads to an increase in the rate of HDR, with a corresponding decrease in the rate of NHEJ repair. We then investigated whether a similar cold shock could lead to an increase in the rate of HDR in the mouse embryo. By analyzing the efficiency of gene editing using single nucleotide polymorphism changes and loxP insertion at three different genetic loci, we found that a transient reduction in temperature after zygote electroporation of CRISPR-Cas9 ribonucleoprotein with a single-stranded oligodeoxynucleotide repair template did indeed increase knockin efficiency, without affecting embryonic development. The efficiency of gene editing with and without the cold shock was first assessed by genotyping blastocysts. As a proof of concept, we then confirmed that the modified embryo culture conditions were compatible with live births by targeting the coat color gene tyrosinase and observing the repair of the albino mutation. Taken together, our data suggest that a transient cold shock could offer a simple and robust way to improve knockin outcomes in both stem cells and zygotes.

Impact of intraoperative hypothermia on the recovery period of anesthesia in elderly patients undergoing abdominal surgery.

BACKGROUND: This study aimed to investigate the impact of intraoperative hypothermia on the recovery period of anesthesia in elderly patients undergoing abdominal surgery. METHODS: A prospective observational study was conducted based on inclusion and exclusion criteria. A total of 384 elderly patients undergoing abdominal surgery under general anesthesia were enrolled in a grade A tertiary hospital in Chengdu, Sichuan Province from October 2021 and October 2022. After anesthesia induction, inflatable warming blankets were routinely used for active heat preservation, and nasopharyngeal temperature was monitored to observe the occurrence of intraoperative hypothermia. Patients were divided into hypothermia group and nonhypothermia group according to whether hypothermia occurred during the operation. Anesthesia recovery time and the incidence of adverse events or unwanted events during anesthesia recovery between the two groups were compared. RESULTS: The numbers (percentage) of 384 patients who underwent abdominal surgery developed intraoperative hypothermia occurred in 240 (62.5%) patients, all of whom had mild hypothermia. There were statistically significant differences between mild hypothermia after active warming and nonhypothermia in the occurrence of shivering (χ2 = 5.197, P = 0.023) and anesthesia recovery time (Z = -2.269, P = 0.02) in elderly patients undergoing abdominal surgery during anesthesia recovery, and there were no statistically significant differences in hypoxemia, nausea or vomiting, hypertension, hypokalemia, hypocalcemia, analgesic drug use,postoperative wound infection or postoperative hospitalization days. CONCLUSIONS: The incidence of intraoperative mild hypothermia after active warming was high in elderly patients who underwent abdominal surgery. Mild hypothermia increased the incidence of shivering and prolonged anesthesia recovery time in elderly patients undergoing abdominal surgery.

An untargeted metabolomics approach to study changes of the medium during human cornea culture.

INTRODUCTION: Two main approaches (organ culture and hypothermia) for the preservation and storage of human donor corneas are globally adopted for corneal preservation before the transplant. Hypothermia is a hypothermic storage which slows down cellular metabolism while organ culture, a corneal culture performed at 28-37 °C, maintains an active corneal metabolism. Researchers, till now, have just studied the impact of organ culture on human cornea after manipulating and disrupting tissues. OBJECTIVES: The aim of the current work was to optimize an analytical procedure which can be useful for discovering biomarkers capable of predicting tissue health status. For the first time, this research proposed a preliminary metabolomics study on medium for organ culture without manipulating and disrupting the valuable human tissues which could be still used for transplantation. METHODS: In particular, the present research proposed a method for investigating changes in the medium, over a storage period of 20 days, in presence and absence of a human donor cornea. An untargeted metabolomics approach using UHPLC-QTOF was developed to deeply investigate the differences on metabolites and metabolic pathways and the influence of the presence of the cornea inside the medium. RESULTS: Differences in the expression of some compounds emerged from this preliminary metabolomics approach, in particular in medium maintained for 10 and 20 days in presence but also in the absence of cornea. A total of 173 metabolites have been annotated and 36 pathways were enriched by pathway analysis. CONCLUSION: The results revealed a valuable untargeted metabolomics approach which can be applied in organ culture metabolomics.

Changes in temperature in preheated crystalloids at ambient temperatures relevant to a prehospital setting: an experimental simulation study with the application of prehospital treatment of trauma patients suffering from accidental hypothermia.

BACKGROUND: Accidental hypothermia is common in all trauma patients and contributes to the lethal diamond, increasing both morbidity and mortality. In hypotensive shock, fluid resuscitation is recommended using fluids with a temperature of 37-42°, as fluid temperature can decrease the patient's body temperature. In Sweden, virtually all prehospital services use preheated fluids. The aim of the present study was to investigate how the temperature of preheated infusion fluids is affected by the ambient temperatures and flow rates relevant for prehospital emergency care. METHODS: In this experimental simulation study, temperature changes in crystalloids preheated to 39 °C were evaluated. The fluid temperature changes were measured both in the infusion bag and at the patient end of the infusion system. Measurements were conducted in conditions relevant to prehospital emergency care, with ambient temperatures varying between - 4 and 28 °C and flow rates of 1000 ml/h and 6000 ml/h, through an uninsulated infusion set at a length of 175 cm. RESULTS: The flow rate and ambient temperature affected the temperature in the infusion fluid both in the infusion bag and at the patient end of the system. A lower ambient temperature and lower flow rate were both associated with a greater temperature loss in the infusion fluid. CONCLUSION: This study shows that both a high infusion rate and a high ambient temperature are needed if an infusion fluid preheated to 39 °C is to remain above 37 °C when it reaches the patient using a 175-cm-long uninsulated infusion set. It is apparent that the lower the ambient temperature, the higher the flow rate needs to be to limit temperature loss of the fluid.

Hypothermia effects on neuronal plasticity post spinal cord injury.

BACKGROUND: SCI is a time-sensitive debilitating neurological condition without treatment options. Although the central nervous system is not programmed for effective endogenous repairs or regeneration, neuroplasticity partially compensates for the dysfunction consequences of SCI. OBJECTIVE AND HYPOTHESIS: The purpose of our study is to investigate whether early induction of hypothermia impacts neuronal tissue compensatory mechanisms. Our hypothesis is that although neuroplasticity happens within the neuropathways, both above (forelimbs) and below (hindlimbs) the site of spinal cord injury (SCI), hypothermia further influences the upper limbs' SSEP signals, even when the SCI is mid-thoracic. STUDY DESIGN: A total of 30 male and female adult rats are randomly assigned to four groups (n = 7): sham group, control group undergoing only laminectomy, injury group with normothermia (37°C), and injury group with hypothermia (32°C +/-0.5°C). METHODS: The NYU-Impactor is used to induce mid-thoracic (T8) moderate (12.5 mm) midline contusive injury in rats. Somatosensory evoked potential (SSEP) is an objective and non-invasive procedure to assess the functionality of selective neuropathways. SSEP monitoring of baseline, and on days 4 and 7 post-SCI are performed. RESULTS: Statistical analysis shows that there are significant differences between the SSEP signal amplitudes recorded when stimulating either forelimb in the group of rats with normothermia compared to the rats treated with 2h of hypothermia on day 4 (left forelimb, p = 0.0417 and right forelimb, p = 0.0012) and on day 7 (left forelimb, p = 0.0332 and right forelimb, p = 0.0133) post-SCI. CONCLUSION: Our results show that the forelimbs SSEP signals from the two groups of injuries with and without hypothermia have statistically significant differences on days 4 and 7. This indicates the neuroprotective effect of early hypothermia and its influences on stimulating further the neuroplasticity within the upper limbs neural network post-SCI. Timely detection of neuroplasticity and identifying the endogenous and exogenous factors have clinical applications in planning a more effective rehabilitation and functional electrical stimulation (FES) interventions in SCI patients.

Implementation of a quality improvement initiative for standardising essential newborn care in a teaching public hospital in rural central India.

OBJECTIVE: Our aim was to refine the essential newborn care practices by employing the multidisciplinary peer team-led quality improvement (QI) projects. DESIGN: In 2017, concerning the same, the department focused on early initiation of breast feeding, prevention of hypothermia within an hour of life and rational usage of antibiotics among babies admitted to neonatal intensive care unit (NICU). Baseline data reported the rate of initiation of breast feeding, hypothermia and antibiotic exposure rate as 35%, 78% and 75%, respectively. Root causes were analysed and a series of Plan-Do-Study-Act cycles were conducted to test the changes. The process of change was studied through run charts (whereas control charts were used for study purpose). RESULT: After the implementation of the QI projects, the rate of initiation of breast feeding was found to be improved from 35% to 90%, the incidence of hypothermia got reduced from 78% to 10% and the antibiotic exposure rate declined from 75% to 20%. Along with the improvement in indicators related to essential newborn care, down the stream we found a decrease in the percentage of culture-positive sepsis rate in the NICU. CONCLUSION: Peer team-led QI initiatives in a resource-limited setting proved beneficial in improving essential newborn care practices.

The Protective Effect and Mechanism of Mild Hypothermia on Lung Injury after Cardiopulmonary Resuscitation in Pigs.

To explore the protective effect and mechanism of mild hypothermia on lung tissue damage after cardiopulmonary resuscitation in pigs. In this experiment, we electrically stimulated 16 pigs (30 ± 2 kg) for 10 min to cause ventricular fibrillation. The successfully resuscitated animals were randomly divided into two groups, a mild hypothermia group and a control group. We took arterial blood 0.5, 1, 3, and 6 h after ROSC recovery in the two groups of animals for blood gas analysis. We observed the structural changes of lung tissue under an electron microscope and calculate the wet weight/dry weight (W/D) ratio. We quantitatively analyzed the expression differences of representative inflammatory factors [interleukin-6 (IL-6) and tumor necrosis factor-alpha TNF-α)] through the ELISA test. We detected the expression levels of Bax, Bcl-2, and Caspase-3 proteins in lung tissues by Western blot. After 3 h and 6 h of spontaneous circulation was restored, compared with the control group, PaO2/FiO2 decreased significantly (P < 0.05). In addition, the pathological changes, lung W/D and lung MDA of the mild hypothermia group were better than those of the control group. The levels of IL-6 and TNF-α in the lung tissue of the mild hypothermia group were significantly lower than those of the control group (P < 0.05). The content of Caspase-3 and Bax in the mild hypothermia group was significantly lower than that of the control group. Our experiments have shown that mild hypothermia can reduce lung tissue damage after cardiopulmonary resuscitation.

Effect of RARC-ERAS nursing program on clinical outcomes in patients undergoing RARC surgery: a retrospective, propensity matching study.

Currently, there is no specific perioperative nursing standard for RARC based on the ERAS concept. This retrospective study investigates to analyze the effect of RARC-ERAS nursing program on VTE and other clinical outcomes in patients undergoing RARC surgery. This retrospective study included 216 patients undergoing RARC surgery From January 1, 2022 to December 30, 2023, and propensity score adjustment analysis was applied. The study compares a control group receiving traditional nursing and an observation group receiving RARC-ERAS nursing program. Perioperative variables and other postoperative complications were retrieved from the hospital medical records. After propensity score matching, there were no significant differences in the demographic and clinical characteristics between the two groups (p > 0.05). The ERAS group exhibited aa significantly higher rate of postoperative unobstructed venous blood flow in the lower extremities by color Doppler ultrasound as compared to the control group (94.6% VS 80.4%, p = 0.042). Before anesthesia induction, lower preoperative anxiety and surgical information needs scores were observed in the ERAS group than in the control group (p < 0.05). Compared to the control group, the ERAS group demonstrated a shorter surgical duration, a lower incidence of perioperative hypothermia, less time needed for getting out of bed, anal exhaust, and for defecation after returning to the ward (p < 0.05). RARC-ERAS nursing program significantly increased the rate of postoperative unobstructed venous blood flow in the lower extremities by color doppler ultrasound, lower preoperative anxiety and intraoperative hypothermia in patients undergoing RARC. This nursing approach presents a valuable strategy for enhancing patient outcomes and merits further exploration in clinical practice.Trial registration:ChiCTR2400081118; http://www.chictr.org.cn , Principal investigator: Mang-mang He, Date of registration: Feb 22, 2024.

Código encefalopatía hipóxico-isquémica: revisión sistematizada para entornos con recursos limitados / Hypoxic-ischaemic encephalopathy code: a systematic review for resource-limited settings

Se estima que el 96% de los recién nacidos (RN) con encefalopatía hipóxico-isquémica (EHI) nacen en entornos con recursos limitados (ERL) sin capacidad para ofrecer el estándar asistencial vigente desde hace cerca de 15 años en los países con altos recursos y que incluye hipotermia terapéutica, neuromonitorización continua electroencefalográfica y resonancia magnética, además de un control intensivo de las constantes vitales y del equilibrio homeostático. Esta situación no parece estar cambiando; sin embargo y aún con estas limitaciones, el conocimiento actualmente disponible permite mejorar la asistencia de los pacientes con EHI atendidos en ERL. El propósito de esta revisión sistematizada es ofrecer, bajo el término «código EHI», recomendaciones de prácticas asistenciales basadas en evidencia científica y factibles en ERL, que permitan optimizar la atención del RN con EHI y ayuden potencialmente a reducir los riesgos asociados a la comorbilidad y a mejorar los resultados neuroevolutivos. El contenido del código EHI se agrupó en nueve epígrafes: 1) prevención de la EHI, 2) reanimación, 3) primeras seis horas de vida, 4) identificación y graduación de la EHI, 5) manejo de las convulsiones, 6) otras intervenciones terapéuticas, 7) disfunción multiorgánica, 8) estudios complementarios, y 9) atención a la familia. (AU)

It is estimated that 96% of infants with hypoxic-ischaemic encephalopathy (HIE) are born in resource-limited settings with no capacity to provide the standard of care that has been established for nearly 15 years in high-resource countries, which includes therapeutic hypothermia, continuous electroencephalographic monitoring and magnetic resonance imaging in addition to close vital signs and haemodynamic monitoring. This situation does not seem to be changing; however, even with these limitations, currently available knowledge can help improve the care of HIE patients in resource-limited settings. The purpose of this systematic review was to provide, under the term «HIE Code», evidence-based recommendations for feasible care practices to optimise the care of infants with HIE and potentially help reduce the risks associated with comorbidity and improve neurodevelopmental outcomes. The content of the HIE code was grouped under 9 headings: 1) prevention of HIE, 2) resuscitation, 3) first 6hours post birth, 4) identification and grading of encephalopathy, 5) seizure management, 6) other therapeutic interventions, 7) multiple organ dysfunction, 8) diagnostic tests and 9) family care. (AU)

Factors Influencing the Occurrence of Intraoperative Hypothermia in Patients Undergoing General Anesthesia Intervention: A Study in a Tertiary Care Hospital.

BACKGROUND Intraoperative and postoperative hypothermia of patients can be caused by the use of anesthetic drugs and the complicated and time-consuming procedures of interventional surgery. This retrospective study included 184 patients to investigate the incidence and factors associated with hypothermia during intraoperative anesthesia in a single center in China between January and October 2023. MATERIAL AND METHODS A convenient sampling method was used to select 184 patients who underwent general anesthesia intervention in a tertiary hospital in Sichuan Province from January to October 2023 as the study population. The independent factors influencing the occurrence of intraoperative hypothermia were analyzed. A survey was conducted to collect 5 demographic factors, 4 preoperative-related factors, and 10 surgically related factors. According to the occurrence of intraoperative hypothermia, the independent influencing factors of unplanned hypothermia during perioperative period were further analyzed. RESULTS Among 184 patients, 64 (34.78%) experienced perioperative unplanned hypothermia, of which 5 (7.81%) cases occurred before the start of surgery, 7 (10.94%) occurred before the start of surgery after anesthesia, and 52 (81.25%) occurred during surgery. Logistic regression analysis showed that body temperature at the beginning of surgery (P<0.001), set operating room temperature (P<0.001), duration of anesthesia (P=0.006), and age (P=0.001) were independent influencing factors for unplanned hypothermia during perioperative period. CONCLUSIONS The incidence of intraoperative hypothermia is high in patients undergoing general anesthesia interventions. Age, duration of anesthesia, set operating room temperature, and body temperature at the beginning of the operation were independent influencing factors for the occurrence of unplanned hypothermia during the perioperative period.

Transient changes in the ST-T waveform mimicking myocardial infarction in a child with near-drowning: a case report.

Drowning is a common cause of childhood morbidity and mortality worldwide. Anoxia, hypothermia, and metabolic acidosis are mainly responsible for this morbidity. Drowning may lead to multiple organ damage, especially cardiac damage, in cases in which severe hypothermia and hypoxemia occur. We report a case of a 4-year-old girl who was admitted to our hospital's Emergency Department because of drowning. She had elevated troponin I concentrations and ST-segment elevation with T wave inversion. However, cardiovascular computed tomography showed no obvious abnormalities in the coronary arteries. We suggest that cardiac damage in this situation is caused by coronary artery spasms. To the best of our knowledge, this is the first case of cardiac damage with electrocardiographic changes after drowning in a preschool child.

The combination treatment of hypothermia and intranasal insulin ameliorates the structural and functional changes in a rat model of traumatic brain injury.

The present study aimed to investigate the combination effects of hypothermia (HT) and intranasal insulin (INS) on structural changes of the hippocampus and cognitive impairments in the traumatic brain injury (TBI) rat model. The rats were divided randomly into the following five groups (n = 10): Sham, TBI, TBI with HT treatment for 3 h (TBI + HT), TBI with INS (ten microliters of insulin) treatment daily for 7 days (TBI + INS), and TBI with combining HT and INS (TBI + HT + INS). At the end of the 7th day, the open field and the Morris water maze tests were done for evaluation of anxiety-like behavior and memory performance. Then, after sacrificing, the brain was removed for stereological study. TBI led to an increase in the total volume of hippocampal subfields CA1 and DG and a decrease in the total number of neurons and non-neuronal cells in both sub-regions, which was associated with anxiety-like behavior and memory impairment. Although, the combination of HT and INS prevented the increased hippocampal volume and cell loss and improved behavioral performances in the TBI group. Our study suggests that the combined treatment of HT and INS could prevent increased hippocampal volume and cell loss in CA1 and DG sub-regions and consequently improve anxiety-like behaviors and memory impairment following TBI.

Biofilm exopolysaccharides alter sensory-neuron-mediated sickness during lung infection.

Infections of the lung cause observable sickness thought to be secondary to inflammation. Signs of sickness are crucial to alert others via behavioral-immune responses to limit contact with contagious individuals. Gram-negative bacteria produce exopolysaccharide (EPS) that provides microbial protection; however, the impact of EPS on sickness remains uncertain. Using genome-engineered Pseudomonas aeruginosa (P. aeruginosa) strains, we compared EPS-producers versus non-producers and a virulent Escherichia coli (E. coli) lung infection model in male and female mice. EPS-negative P. aeruginosa and virulent E. coli infection caused severe sickness, behavioral alterations, inflammation, and hypothermia mediated by TLR4 detection of the exposed lipopolysaccharide (LPS) in lung TRPV1+ sensory neurons. However, inflammation did not account for sickness. Stimulation of lung nociceptors induced acute stress responses in the paraventricular hypothalamic nuclei by activating corticotropin-releasing hormone neurons responsible for sickness behavior and hypothermia. Thus, EPS-producing biofilm pathogens evade initiating a lung-brain sensory neuronal response that results in sickness.

Characterizing the impact of thermoregulation in patients after cardiac arrest: a retrospective cohort study.

PURPOSE: Core body temperature has been extensively investigated as a thereuptic target in care after cardiac arrest. Nevertheless, the integrity of thermoregulation in patients after cardiac arrest has not been well studied. We sought to evaluate whether low spontaneous body temperature after cardiac arrest is associated with increased death and a worse neurologic outcome, and whether patients with low spontaneous body temperature exhibit features suggestive of impaired thermoregulation. METHODS: We conducted a single-centre retrospective cohort study. We included all adult patients who underwent temperature control with hypothermia after cardiac arrest between 1 January 2014 and 30 June 2020. The primary exposure was low spontaneous core body temperature (< 35 °C) at initiation of hypothermia therapy. The primary outcome was in-hospital death and the secondary outcome was poor neurologic outcomes at discharge. RESULTS: Five hundred and ninety-seven adult patients, comprising both in- and out-of-hospital cardiac arrests, were included. Patients with low spontaneous body temperature also had slightly lower average temperature, and more frequent transient but controlled breakthrough fever episodes in the first 24 hr. In the multivariable logistic regression analysis, low spontaneous body temperature was associated with higher odds of in-hospital death (odds ratio, 2.9; 95% confidence interval, 1.9 to 4.2; P < 0.001). CONCLUSION: In this single-centre retrospective cohort study, low spontaneous core body temperature was associated with poor outcomes in patients after cardiac arrest. Patients with low spontaneous body temperature also exhibited features suggestive of impaired thermoregulation. Further research is needed to determine whether body temperature upon presentation reflects the robustness of the patient's underlying physiology and severity of brain insult after a cardiac arrest.

RéSUMé: OBJECTIF: La température corporelle centrale a fait l'objet d'études approfondies en tant que cible thérapeutique dans les soins après un arrêt cardiaque. Néanmoins, l'intégrité de la thermorégulation après un arrêt cardiaque n'a pas été bien étudiée. Nous avons cherché à évaluer si une température corporelle spontanément basse après un arrêt cardiaque était associée à une augmentation de la mortalité et à une issue neurologique plus grave, et si les individus ayant une température corporelle spontanément basse présentaient des caractéristiques suggérant une altération de la thermorégulation. MéTHODE: Nous avons mené une étude de cohorte rétrospective monocentrique. Nous avons inclus tou·tes les patient·es adultes ayant bénéficié d'un contrôle de température lors d'une hypothermie après un arrêt cardiaque entre le 1er janvier 2014 et le 30 juin 2020. L'exposition principale était une température corporelle centrale spontanément basse (< 35 °C) au début du traitement de l'hypothermie. Le critère d'évaluation principal était le décès à l'hôpital, et le critère d'évaluation secondaire était de mauvaises issues neurologiques à la sortie de l'hôpital. RéSULTATS: Cinq cent quatre-vingt-dix-sept patient·es adultes, ayant subi des arrêts cardiaques à l'hôpital ou hors de l'hôpital, ont été inclus·es. Les patient·es ayant une température corporelle spontanément basse avaient également une température moyenne légèrement plus basse et des épisodes de fièvre paroxystique transitoires mais contrôlés plus fréquents au cours des premières 24 heures. Dans l'analyse de régression logistique multivariée, une température corporelle spontanément basse était associée à une probabilité plus élevée de décès à l'hôpital (rapport de cotes, 2,9; intervalle de confiance à 95 %, 1,9 à 4,2; P < 0,001). CONCLUSION: Dans cette étude de cohorte rétrospective monocentrique, une température corporelle centrale spontanément basse a été associée à de mauvais devenirs après un arrêt cardiaque. Les patient·es présentant une température corporelle spontanément basse présentaient également des caractéristiques suggérant une altération de la thermorégulation. D'autres recherches sont nécessaires pour déterminer si la température corporelle lors de la présentation reflète la robustesse de la physiologie sous-jacente des patient·es et la gravité de la lésion cérébrale après un arrêt cardiaque.

Hypothermic Cardiac Arrest: A Case Report of an Unexpected Survivor Using Air Medical Transportation in Nepal.

This is a case of a 34-year-old man surviving hypothermic cardiac arrest with excellent neurologic recovery in Nepal. After 3 days without communication at an altitude of approximately 6,000 m, the patient was located in a crevasse and retrieved by a helicopter-supported search and rescue team. At first contact, he was reported to be breathing and shivering with appropriate pupillary response. The patient was then flown to a local teaching hospital where he was assessed on arrival and found to be in cardiac arrest with absence of spontaneous breathing and a central pulse and bilaterally fixed and dilated pupils. An electrocardiogram demonstrated asystole, and his core temperature was unrecordably low on the available device. After resuscitation and return of spontaneous circulation, the patient received a secondary helicopter transfer to a major hospital in the capital, Kathmandu, where his recovery continued. The report discusses the physiological basis of the relatively favorable outcomes observed in hypothermic cardiac arrest and highlights the operations and capability of helicopter emergency medical services in a country on the United Nations list of least developed nations.

Delayed Rewarming Thrombocytopenia: A Suggested Preventable and Treatable Cause of Rewarming Deaths.

The lack of a consensus of accepted prognostic factors in hypothermia suggests an additional factor has been overlooked. Delayed rewarming thrombocytopenia (DRT) is a novel candidate for such a role. At body temperature, platelets undergoing a first stage of aggregation are capable of progression to a second irreversible stage of aggregation. However, we have shown that the second stage of aggregation does not occur below 32°C and that this causes the first stage to become augmented (first-stage platelet hyperaggregation). In aggregometer studies performed below 32°C, the use of quantities of ADP that cause a marked first-stage hyperaggregation can cause an augmented second-stage activation of the platelets during rewarming (second-stage platelet hyperaggregation). In vivo, after 24 hours of hypothermia, platelets on rewarming seem to undergo second-stage hyperaggregation, from ADP released from erythrocytes, leading to life-threatening thrombocytopenia. This hyperaggregation is avoidable if heparin is given before the hypothermia or if aspirin, alcohol or platelet transfusion is given during the hypothermia before reaching 32°C on rewarming. Many of the open questions existing in this field are explained by DRT. Prevention and treatment of DRT could be of significant value in preventing rewarming deaths and some cases of rescue collapse. Performing platelet counts during rewarming will demonstrate potentially fatal thrombocytopenia and enable treatment with platelet infusions aspirin or alcohol.