BACKGROUND Perioperative hypothermia(PH)negatively affects the physical and mental health of patients to varying degrees.Currently,there is no effective multidisciplinary team(MDT)intervention for gynecological patien...BACKGROUND Perioperative hypothermia(PH)negatively affects the physical and mental health of patients to varying degrees.Currently,there is no effective multidisciplinary team(MDT)intervention for gynecological patients with PH.AIM To apply the best evidence on the prevention and management of PH in gynecological patients,improve the quality of perioperative evidence-based care based on treatment by an MDT for gynecological patients and analyze the effect of MDT-and evidence-based practice(EBP)projects on the psychological status and cognitive function of gynecological patients with PH.METHODS Under the guidance of knowledge translation and combined with the opinions of involved stakeholders and clinical experts,the best evidence for PH prevention and management in gynecological patients was selected and adjusted to suit the practice setting.Based on the evidence,the practice plan was developed,and the MDT intervention was carried out in the preoperative ward,the preoperative preparation room,the intraoperative operating room,the postanesthesia care unit,and the 24-hour postoperative gynecological ward through the EBP program.The incidence of hypothermia,the nurses’awareness,the implementation rate of examination indicators,and the thermal comfort level,psychological status and cognitive function of patients were compared before and after the implementation of the program.RESULTS The incidence of PH in gynecological patients decreased from 43.33%to 13.33%after the implementation of the scheme.The implementation rate of examination indicators 6-10,12,14,16-18,21,and 22 reached 100%,and that of other indicators was above 90%,except for examination indicators 5 and 13,which was 66.67%;the indices were significantly improved compared with the baseline(before evidence application)(P<0.05).The score of nurses'awareness of PH prevention and management in gynecological patients increased from 60.96±9.70 to 88.08±8.96,and the difference was statistically significant(P<0.001).The total score of the perioperative thermal comfort level of patients undergoing gynecological surgery was 27.97±2.04,which was significantly increased compared with the score of 21.27±1.57 observed by researchers at baseline(P<0.001).The perioperative Hamilton Depression Scale and Hamilton Anxiety Scale scores of patients undergoing gynecological surgery decreased from 15.03±3.16 and 13.93±2.64 to 4.30±1.15 and 3.53±0.78,respectively,with statistically significant differences(P<0.001).The perioperative Montreal Cognitive Assessment Scale score of the gynecological surgery patients increased from 23.17±1.68 to 26.93±1.11,also with statistical significance(P<0.001).CONCLUSION MDT-based EBP for PH prevention and management in gynecological patients during the perioperative period can standardize nursing operations,improve nurses'awareness and behavioral compliance with gynecological hypothermia management,and reduce the occurrence of PH in gynecological patients while playing a positive role in reducing patients’negative emotions and enhancing their cognitive function.展开更多
Background: Moderate to severe hypoxic-ischemic encephalopathy (HIE) in neonates is often treated with hypothermia. However, some neonates may experience epileptic seizures during therapeutic hypothermia (TH). Data on...Background: Moderate to severe hypoxic-ischemic encephalopathy (HIE) in neonates is often treated with hypothermia. However, some neonates may experience epileptic seizures during therapeutic hypothermia (TH). Data on the electrophysiologic and evolutionary aspects of these seizures are scarce in African countries. Objectives: To determine the types of epileptic seizures caused by HIE in neonates in Brazzaville;to describe the evolution of background EEG activities during TH and rewarming;to report the evolution of epileptic seizures. Methods: This was a cross-sectional, descriptive study conducted from January 2020 to July 2022. It took place in Brazzaville in the Neonatology Department of the Blanche Gomez Mother and Child Hospital. It focused on term neonates suffering from moderate or severe HIE. They were treated with hypothermia combined with phenobarbital for 72 hours. Results: Among 36 neonates meeting inclusion criteria, there were 18 boys and 18 girls. Thirty-one (86.1%) neonates had grade 2 and 5 (13.9%) grade 3 HIE. In our neonates, HIE had induced isolated electrographic seizures (n = 11;30.6%), electroclinical seizures (n = 25;69.4%), and 6 types of background EEG activity. During TH and rewarming, there were 52.8% of patients with improved background EEG activity, 41.7% of patients with unchanged background EEG activity, and 5.5% of patients with worsened background EEG activity. At the end of rewarming, only 9 (25%) patients still had seizures. Conclusion: Isolated electrographic and electroclinical seizures are the only pathological entities found in our studied population. In neonates with moderate HIE, the applied therapeutic strategy positively influences the evolution of both seizures and background EEG activity. On the other hand, in neonates with severe HIE, the same therapeutic strategy is ineffective. .展开更多
Perinatal hypoxic-ischemic encephalopathy is a leading cause of neonatal death and disability.Therapeutic hypothermia significantly reduces death and major disability associated with hypoxic-ischemic encephalopathy;ho...Perinatal hypoxic-ischemic encephalopathy is a leading cause of neonatal death and disability.Therapeutic hypothermia significantly reduces death and major disability associated with hypoxic-ischemic encephalopathy;however,many infants still experience lifelong disabilities to movement,sensation and cognition.Clinical guidelines,based on strong clinical and preclinical evidence,recommend therapeutic hypothermia should be started within 6 hours of birth and continued for a period of 72 hours,with a target brain temperature of 33.5 ±0.5℃ for infants with moderate to severe hypoxic-ischemic encephalopathy.The clinical guidelines also recommend that infants be re warmed at a rate of 0.5℃ per hour,but this is not based on strong evidence.There are no randomized controlled trials investigating the optimal rate of rewarming after therapeutic hypothermia for infants with hypoxic-ischemic encephalopathy.Preclinical studies of rewarming are conflicting and results were confounded by treatment with sub-optimal durations of hypothermia.In this review,we evaluate the evidence for the optimal start time,duration and depth of hypothermia,and whether the rate of rewarming after treatment affects brain injury and neurological outcomes.展开更多
Selective brain hypothermia is considered an effective treatment for neuronal injury after stroke,and avoids the complications of general hypothermia.However,the mechanisms by which selective brain hypothermia affects...Selective brain hypothermia is considered an effective treatment for neuronal injury after stroke,and avoids the complications of general hypothermia.However,the mechanisms by which selective brain hypothermia affects mitochondrial fission remain unknown.In this study,we investigated the effect of selective brain hypothermia on the expression of fission 1 (Fis1) protein,a key factor in the mitochondrial fission system,during focal cerebral ischemia/reperfusion injury.Sprague-Dawley rats were divided into four groups.In the sham group,the carotid arteries were exposed only.In the other three groups,middle cerebral artery occlusion was performed using the intraluminal filament technique.After 2 hours of occlusion,the filament was slowly removed to allow blood reperfusion in the ischemia/reperfusion group.Saline,at 4℃ and 37℃,were perfused through the carotid artery in the hypothermia and normothermia groups,respectively,followed by restoration of blood flow.Neurological function was assessed with the Zea Longa 5-point scoring method.Cerebral infarct volume was assessed by 2,3,5-triphenyltetrazolium chloride staining,and apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining.Fis1 and cytosolic cytochrome c levels were assessed by western blot assay.Fis1 mRNA expression was assessed by quantitative reverse transcription-polymerase chain reaction.Mitochondrial ultrastructure was evaluated by transmission electron microscopy.Compared with the sham group,apoptosis,Fis1 protein and mRNA expression and cytosolic cytochrome c levels in the cortical ischemic penumbra and cerebral infarct volume were increased after reperfusion in the other three groups.These changes caused by cerebral ischemia/reperfusion were inhibited in the hypothermia group compared with the normothermia group.These findings show that selective brain hypothermia inhibits Fis1 expression and reduces apoptosis,thereby ameliorating focal cerebral ischemia/reperfusion injury in rats.Experiments were authorized by the Ethics Committee of Qingdao Municipal Hospital of China (approval No.2019008).展开更多
Objective:To find out whether warm bladder irrigation fluid can decrease the occurrence of perioperative hypothermia,blood loss and shiver in patients treated with benign prostatic hyperplasia(BPH).Method:A comprehens...Objective:To find out whether warm bladder irrigation fluid can decrease the occurrence of perioperative hypothermia,blood loss and shiver in patients treated with benign prostatic hyperplasia(BPH).Method:A comprehensive literature review and meta-analysis that included randomized controlled trials(RCTs)related to temperature of irrigation fluid in the perioperative treatment for BPH was taken by researchers.The relevant literature were searched in Chinese database,such as Retrieval Chinese Journal Full-text Database,VIP Journal Database,Wanfang database,as well as in English search engine and database,including Embase,Cochrane and Medline till January 2018.The study quality was assessed by recommended standards from Cochrane Handbook(version 5.1.0).Results:A total of 28 RCTs and 3858 patients were included.The results showed that the incidences of shiver(risk ratio[RR]Z 0.32,95%confidence interval[CI]:0.28e0.36,p<0.001,I^2 Z 0%)and hypothermia(RR Z 0.36,95%CI:0.21e0.59,p<0.001,I^2 Z 67%)in the group of warm irrigation fluid were lower than the group having room-temperature fluid.Room-temperature irrigation fluid group caused a greater drop in body temperature compared to warm irrigation fluid group(p<0.001,I^2 Z 96%).We performed a narrative descriptive statistics only because of substantial heterogeneity.Conclusions:Warm bladder irrigation fluid can decrease the drop of body temperature and the incidence of hypothermia and shiver during and after the operation for BPH.Warm irrigation fluid should be considered as a standard practice in BPH surgeries.展开更多
AIM: To assess the safety of therapeutic hypothermia(TH) concerning arrhythmias we analyzed serial electrocardiograms(ECG) during TH.METHODS: All patients recovered from a cardiac arrest with Glasgow < 9 at admissi...AIM: To assess the safety of therapeutic hypothermia(TH) concerning arrhythmias we analyzed serial electrocardiograms(ECG) during TH.METHODS: All patients recovered from a cardiac arrest with Glasgow < 9 at admission were treated with induced mild TH to 32-34℃. TH was obtained with cool fluid infusion or a specific intravascular device. Twelvelead ECG before,during,and after TH,as well as ECG telemetry data was recorded in all patients. From a total of 54 patients admitted with cardiac arrest during the study period,47 patients had the 3 ECG and telemetry data available. ECG analysis was blinded and performed with manual caliper by two independent cardiologists from blinded copies of original ECG,recorded at 25 mm/s and 10 mm/m V. Coronary care unit staff analyzed ECG telemetry for rhythm disturbances. Variables measured in ECG were rhythm,RR,PR,QT and corrected QT(QTc by Bazett formula,measured in lead v2) intervals,QRS duration,presence of Osborn's J wave and U wave,as well as ST segment displacement and T wave amplitude in leads Ⅱ,v2 and v5.RESULTS: Heart rate went down an average of 19 bpm during hypothermia and increased again 16 bpm with rewarming(P < 0.0005,both). There was a nonsignificant prolongation of the PR interval during TH and a significant decrease with rewarming(P = 0.041). QRS duration significantly prolonged(P = 0.041) with TH and shortened back(P < 0.005) with rewarming. QTc interval presented a mean prolongation of 58 ms(P < 0.005) during TH and a significant shortening with rewarming of 22.2 ms(P = 0.017). Osborn or J wave was found in 21.3% of the patients. New arrhythmias occurred in 38.3% of the patients. Most frequent arrhythmia was non-sustained ventricular tachycardia(19.1%),followed by severe bradycardia or paced rhythm(10.6%),accelerated nodal rhythm(8.5%) and atrial fibrillation(6.4%). No life threatening arrhythmias(sustained ventricular tachycardia,polymorphic ventricular tachycardia or ventricular fibrillation) occurred during TH. CONCLUSION: A 38.3% of patients had cardiac arrhythmias during TH but without life-threatening arrhythmias. A concern may rise when inducing TH to patients with long QT syndrome.展开更多
Background: The successful treatment of military combat casualties with penetrating injuries is significantly dependent on the time needed to get the patient to an adequate treatment facility. Profound hypothermia ind...Background: The successful treatment of military combat casualties with penetrating injuries is significantly dependent on the time needed to get the patient to an adequate treatment facility. Profound hypothermia induced suspended animation for delayed resuscitation(SADR) is a novel approach for inducing cardiac arrest and buying additional time for such injuries. However, the time used to safely administer circulatory arrest(CA) is controversial. The goal of this study was to evaluate the safety of hypothermia-induced SADR over 90 and 120 min time intervals.Methods: Sixteen male BAMA minipigs were randomized into two groups: CA90 group(90 min, n =8) and CA120 group(120 min, n =8). Cannulation of the right common carotid arteries and internal jugular veins was performed to establish cardiopulmonary bypass for each animal. Through the perfusion of cold organ preservation solution(OPS), cardioplegia and profound hypothermia(15℃) were induced. After CA, cardiopumonary bypass(CPB) was restarted, and the animals were gradually re-warmed and resuscitated. The animals were assisted with ventilators until spontaneous breathing was achieved. The index of hemodynamic perioperative serum chemistry values [alanine transaminase(ALT), aspartate aminotransferase(AST), creatinine(CR), lactic dehydrogenase(LDH) and troponin T(TnT)] and survival were observed from pre-operation to 7 days post-operation.Results: Fifteen animals were enrolled in the experiment, while 1 animal in CA120 group died from surgical error. All 8 animals in CA90 group recovered, with only 1 animal displaying mild disability. However, in CA120 group, only 2 animals survived with severe disability, and the other 5 animals died after 2 days post-operation. In CA90 group, the perioperative serum chemistry values increased at 1 day post-operation(ALT 84.43±18.65 U/L; AST 88.99±23.19 U/L; Cr 87.90±24.49μmol/L; LDH 1894.13±322.26 U/L; TnT 0.849±0.135 ng/ml) but decreased to normal or almost normal levels at 7 days post-operation(ALT 52.48±9.04 U/L; AST 75.23±21.46 U/L; Cr 82.69±18.41μmol/L; LDH 944.67±834.32 U/L; TnT 0.336±0.076 ng/ml).Conclusion: Profound hypothermia-induced SADR is an effective method for inducing cardiac arrest. Our results indicate that inducing CA for 90 min(at 15℃) is safer than doing so for 120 min. Our results indicate that 120 min of CA at 15℃ is dangerous and can result in high mortality and severe neurological complications. Further experimentation is needed to determine whether 120 min of CA at temperatures lower than 15℃ can lead to safe recovery.展开更多
BACKGROUND: Cardiac arrest(CA) is a common and serious event in emergency medicine. Despite recent improvements in resuscitation techniques, the survival rate of patients with CA is unchanged. The present study was un...BACKGROUND: Cardiac arrest(CA) is a common and serious event in emergency medicine. Despite recent improvements in resuscitation techniques, the survival rate of patients with CA is unchanged. The present study was undertaken to observe the effect of mild hypothermia(MH) on the reactive oxygen species(ROS) and the effect of neurological function and related mechanisms.METHODS: Sixty-five healthy male Sprague Dawley(SD) adult rats were randomly(random number) divided into 2 groups: blank control group(n=5) and CPR group(n=60). CA was induced by asphyxia. The surviving rats were randomly(random number) divided into two groups: normothermia CPR group(NT) and hypothermia CPR group(HT). Normothermia of 37 °C was maintained in the NT group after return of spontaneous circulation(ROSC), hypothermal intervention of 32 °C was carried out in the HT group for 4 hours immediately after ROSC. Both the NT and HT groups were then randomly divided into 2 subgroups 12 hours and 24 hours after ROSC(NT-12, NT-24, HT-12, HT-24 subgroups). During observation, the neurological defi cit scores(NDSs) was recorded, then the bilateral hippocampi were obtained from rats' head, and monoplast suspension of fresh hippocampus tissue was made immediately to determine the level of intracellular ROS by flow cytometry. Transmission electron microscope was used to observe the ultramicro changes of cellular nucleus and mitochondria. Reverse transcription-polymerase chain reaction(RT-PCR) was used to determine the expression of caspase-3 m RNA, and western-blotting(WB) was used to determine the level of LC3 in frozen hippocampus tissue. Measured data were analyzed with paired sample t test and One-Way ANOVA.RESULTS: Of 60 rats with CA, 44(73%) were successfully resuscitated and 33(55%) survived until the end of the experiment. The NDSs of rats in the NT and HT groups were more signifi cantly reduced than those in the BC group(F=8.107, P<0.05), whereas the NDSs of rats in the HT-12 and HT-24 subgroups were significantly increased in comparison with those NDSs of rats in the NT-12 and NT-24 subgroups, respectively(t=9.692, P<0.001; t=14.374, P<0.001). The ROS in hippocampus nerve cells in the NT and HT groups signifi cantly increased compared to the BC group(F=16.824, P<0.05), whereas the ROS in the HT-12 and HT-24 subgroups significantly reduced compared with that ROS in the NT-12 and NT-24 subgroups, respectively(t=9.836, P<0.001; t=7.499, P<0.001). The expression of caspase-3 m RNA in hippocampus nerve cells in the NT and HT groups were signifi cantly increased compared to the BC group(F=24.527, P<0.05), whereas the expression of caspase-3 m RNA in rats of the HT-12 and HT-24 subgroups was signifi cantly reduced compared to the NT-12 and NT-24 subgroups, respectively(t=6.935, P<0.001; t=4.317, P<0.001). The expression of LC3B-II/I in hippocampus nerve cells of rats in the NT and HT groups signifi cantlyincreased compared to the BC group(F=6.584, P<0.05), whereas the expression of LC3B-II/I in rats of the HT-12 and HT-24 subgroups significantly reduced compared to the NT-12 and NT-24 subgroups, respectively(t=10.836, P<0.001; t=2.653, P=0.02). Ultrastructure damage of nucleus and mitochondria in the NT group was more evident than in the BC group, and eumorphism of nucleus and mitochondria were maintained in rats of the HT group compared with the NT group.CONCLUSION: Mild hypothermia lessened the injury of nerve cells and improved the neurological function of rats that survived from cardiac arrest by reducing the ROS production of nerve cells and inhibiting the expression of caspase-3 m RNA and LC3, leading to cellular apoptosis and massive autophagy in rats that survived from cardiac arrest after CPR.展开更多
Background: Existing studies have found that some inflammatory factors cause brain cell damage through the TLR4/NF-κB pathway, and that mild hypothermia has a protective effect on nerve cells. It is not clear whether...Background: Existing studies have found that some inflammatory factors cause brain cell damage through the TLR4/NF-κB pathway, and that mild hypothermia has a protective effect on nerve cells. It is not clear whether the mild hypothermic brain protection is achieved through the TLR4/NF-κB pathway in microglia. Objective: To investigate the impacts of mild hypothermia on lipopolysaccharide (LPS)-mediated TLR4/NF-κB signaling pathway in microglia. Method: The cultured microglia cells in vitro were divided into the NS group and the LPS group at 33?C and 37?C, respectively;quantitative RT-PCR was performed to detect the expressions of TLR4 and NF-κB mRNA in the microglia, Western blot was used to detect the expressions of TLR4 and NF-κB protein in the microglia, and ELISA was performed to detect the levels of tumor necrosis factor α (TNF-α) and interleukin-10 (IL-10) in the culture medium. Results: Under the LPS stimulation, the mRNA and protein expressions of TLR4 and NF-κB at different time points had significant changes between the normothermia group and the mild hypothermia group, in which the expressions in the former group were firstly increased and then decreased, while those in the latter showed a continuous increasing trend (P < 0.01);and the expressions of TNF-α in all the groups presented the trend of first-increasing then-decreasing, while IL-10 exhibited one slow linear increasing trend (P Conclusions: Mild hypothermia could inhibit the mRNA and protein expressions of LPS-mediated TLR4/NF-κB signaling pathway in the microglia, and inhibit the production and release of downstream inflammatory cytokines (TNF-α and IL-10).展开更多
BACKGROUND:Induction of hypothermia(a 4℃decrease from baseline)improves outcomes in adult cardiac arrest and neonatal hypoxic ischemic encephalopathy,and may benefit other conditions as well.Methods used to implement...BACKGROUND:Induction of hypothermia(a 4℃decrease from baseline)improves outcomes in adult cardiac arrest and neonatal hypoxic ischemic encephalopathy,and may benefit other conditions as well.Methods used to implement or prevent hypothermia typically require skin contact with blankets or pads or intravascular access with catheter devices.The study was to evaluate the potential to induce mild therapeutic hypothermia via an esophageal route in a porcine model.METHODS:Single-animal proof-of-concept study of a prototype esophageal device in a 70 kg Yorkshire swine.We measured the rate of temperature change after placement of a prototype device to induce hypothermia via the esophagus,and compared this rate to known temperature changes that occur under similar laboratory conditions without a hypothermic device.RESULTS:Swine temperature decreased from a starting temperature of 37.8℃to 33.8℃(achieving the goal of a 4℃decrease)in 175 minutes,resulting in a cooling rate of 1.37℃/h.Histopathology of the esophagus showed normal tissue without evidence of injury.CONCLUSION:A prototype of an esophageal cooling device induced hypothermia effectively in a large single-swine model.展开更多
BACKGROUND:Hypothermia is associated with poor outcome in trauma patients;however,hemorrhagic shock(HS)model with anesthetized swine was different from that of clinical reality.To identify the effects of environmental...BACKGROUND:Hypothermia is associated with poor outcome in trauma patients;however,hemorrhagic shock(HS)model with anesthetized swine was different from that of clinical reality.To identify the effects of environmental hypothermia on HS,we investigated hemodynamics and oxygen dynamics in an unanesthetized swine model of HS under simulating hypothermia environment.METHODS:Totally 16 Bama pigs were randomly divided into ambient temperature group(group A)and low temperature group(group B),8 pigs in each group.Venous blood(30 mL/kg)was continuously withdrawn for more than 15 minutes in conscious swine to establish a hemorrhagic shock model.Pulmonary arterial temperature(Tp),heart rate(HR),mean arterial pressure(MAP),pulmonary arterial pressure(PAP),pulmonary arterial wedge pressure(PAWP),central venous pressure(CVP),cardiac output(CO),hemoglobin(Hb),saturation of mixed venous blood(SvO_2)and blood gas analysis were recorded at the baseline and different hemorrhagic shock time(HST).The whole body oxygen delivery indices,DO_2l and VO_2l,and the O_2 extraction ratio(O_2ER)were calculated.RESULTS:Core body temperature in group A decreased slightly after the hemorrhagic shock model was established,and environmental hypothermia decreased in core body temperature.The mortality rate was significantly higher in group B(50%)than in group A(0%).DO_2l and VO_2l decreased significantly after hemorrhage.No difference was found in hemodynamics,DO_2l and VO_2l between group A and group B,but the difference in pH,lactic acid and O_2ER was significant between the two groups.CONCLUSION:Environmental hypothermia aggravated the disorder of oxygen metabolism after hemorrhagic shock,which was associated with poor prognosis.展开更多
BACKGROUND:Good neurological outcome after cardiac arrest(CA) is hard to achieve for clinicians.Experimental and clinical evidence suggests that therapeutic mild hypothermia is beneficial.This study aimed to assess th...BACKGROUND:Good neurological outcome after cardiac arrest(CA) is hard to achieve for clinicians.Experimental and clinical evidence suggests that therapeutic mild hypothermia is beneficial.This study aimed to assess the effectiveness and safety of therapeutic mild hypothermia in patients successfully resuscitated from CA using a meta-analysis.METHODS:We searched the MEDLINE(1966 to April 2012),OVID(1980 to April 2012),EMBASE(1980 to April 2012),Chinese bio-medical literature & retrieval system(CBM)(1978 to April 2012),Chinese medical current contents(CMCC)(1995 to April 2012),and Chinese medical academic conference(CMAC)(1994 to April 2012).Studies were included if 1) the study design was a randomized controlled trial(RCT);2) the study population included patients successfully resuscitated from CA,and received either standard post-resuscitation care with normothermia or mild hypothermia;3) the study provided data on good neurologic outcome and survival to hospital discharge.Relative risk(RR) and 95%confidence interval(CI) were used to pool the effect.RESULTS:The study included four RCTs with a total of 417 patients successfully resuscitated from CA.Compared to standard post-resuscitation care with normothermia,patients in the hypothermia group were more likely to have good neurologic outcome(RR=1.43,95%CI 1.14-1.80,P=0.002) and were more likely to survive to hospital discharge(RR=1.32,95%CI 1.08-1.63,P=0.008).There was no significant difference in adverse events between the normothermia and hypothermia groups(P>0.05),nor heterogeneity and publication bias.CONCLUSION:Therapeutic mild hypothermia improves neurologic outcome and survival in patients successfully resuscitated from CA.展开更多
Aim: The relationship between preoperative anxiety level and intraoperative hypothermia (<36℃) was investigated. Background: Core temperature often decreases during surgery, with an initial rapid decrease followed...Aim: The relationship between preoperative anxiety level and intraoperative hypothermia (<36℃) was investigated. Background: Core temperature often decreases during surgery, with an initial rapid decrease followed by a slower decrease for about 2 hours. Preoperative anxiety may influence perioperative physiological responses. The relationship between preoperative anxiety level and perioperative decrease in core temperature has not been studied closely. Design: A prospective observational study. Methods: This study enrolled 120 adult patients who underwent elective major abdominal surgery under combined epidural and general anesthesia. Tympanic membrane temperature was used to measure core temperature preoperatively and during the operation. The relationship between anxiety level according to the State-Trait Anxiety Inventory (STAI) and core temperature was examined using descriptive and multivariate risk analysis. Results: High anxiety level was found in 61 patients (51%), of which 26 (43%) developed hypothermia during the first hour and 40 (66%) developed hypothermia during the first 2 hours of anesthesia. After adjustment for covariates, patients with a high anxiety level were found to have a 2.17-fold higher risk of hypothermia during the first hour and a 1.77-fold higher risk of hypothermia during the first 2 hours than patients with a low/moderate anxiety level. Conclusions: The risk of hypothermia in the early phase of general anesthesia can be predicted by measurement of the preoperative anxiety level using the STAI. Relevance to Clinical Practice: Patients with a high anxiety level had a significantly higher risk of intraoperative hypothermia. Preoperative preventive nursing care programs should include anxiety management and thermal care.展开更多
We have used a nonlinear one-dimensional heat transfer model based on temperature-dependent blood perfusion to predict temperature distribution in dermis and subcutaneous tissues subjected to point heating sources. By...We have used a nonlinear one-dimensional heat transfer model based on temperature-dependent blood perfusion to predict temperature distribution in dermis and subcutaneous tissues subjected to point heating sources. By using Jacobi elliptic functions, we have first found the analytic solution corresponding to the steady-state temperature distribution in the tissue. With the obtained analytic steady-state temperature, the effects of the thermal conductivity, the blood perfusion, the metabolic heat generation, and the coefficient of heat transfer on the temperature distribution in living tissues are numerically analyzed. Our results show that the derived analytic steady-state temperature is useful to easily and accurately study the thermal behavior of the biological system, and can be extended to such applications as parameter measurement, temperature field reconstruction and clinical treatment.展开更多
Therapeutic hypothermia is today used in several clinical settings, among them the gut related diseases that are influenced by ischemia/reperfusion injury. This perspective paved the way to the study of hibernation ph...Therapeutic hypothermia is today used in several clinical settings, among them the gut related diseases that are influenced by ischemia/reperfusion injury. This perspective paved the way to the study of hibernation physiology, in natural hibernators, highlighting an unexpected importance of the gut microbial ecosystem in hibernation and torpor. In natural hibernators, intestinal microbes adaptively reorganize their structural configuration during torpor, and maintain a mutualistic configuration regardless of long periods of fasting and cold temperatures. This allows the gut microbiome to provide the host with metabolites, which are essential to keep the host immunological and metabolic homeostasis during hibernation. The emerging role of the gut microbiota in the hibernation process suggests the importance of maintaining a mutualistic gut microbiota configuration in the application of therapeutic hypothermia as well as in the development of new strategy such as the use of synthetic torpor in humans. The possible utilization of tailored probiotics to mold the gut ecosystem during therapeutic hypothermia can also be taken into consideration as new therapeutic strategy.展开更多
BACKGROUND:The study aimed to explore the effects of hypothermia state induced by4 ℃ normal saline(NS) on liver biochemistry,enzymology and morphology after restoration of spontaneous circulation(ROSC) by cardiopulmo...BACKGROUND:The study aimed to explore the effects of hypothermia state induced by4 ℃ normal saline(NS) on liver biochemistry,enzymology and morphology after restoration of spontaneous circulation(ROSC) by cardiopulmonary resuscitation(CPR) in swine.METHODS:After 4 minutes of ventricular fibrillation(VF),standard CPR was carried out.Then the survivors were divided into two groups:low temperature group and normal temperature group.The low temperature(LT) group(n-5) received continuously 4 °C NS at the speed of 1.33 mL/kg per minute for 22 minutes,then at the speed lowering to 10 mL/kg per hour.The normal temperature(NT) group(n-5) received NS with normal room temperature at the same speed of the LT group.Hemodynamic status and oxygen metabolism were monitored and the levels of serum alanine aminotransferase(ALT),aspartate aminotransferase(AST) and lactate dehydrogenase(LDH) were measured in blood samples obtained at baseline and at 10 minutes,2 hours and 4 hours after ROSC.At 24 hours after ROSC,the animals were killed and the liver was removed to determine the Na^+-K^+-ATPase and Ca^(2+)-ATPase enzyme activities and histological changes under a light or electron microscope.RESULTS:Core temperature was decreased in the LT group(P<0.05),while HR,MAP and CPP were not significantly decreased(P>0.05) compared with the NT group(P>0.05).The oxygen extraction ratio was lower in the LT group than in the NT group(P<0.05).The serum levels of ALT,AST and LDH increased in both groups but not significantly in the LT group.The enzyme activity of liver ATP was much higher in the LT group(Na^+-K^+-ATP enzyme:8.64±3.32 U vs.3.28±0.71 U;Ca^(2+)-ATP enzyme:10.92±2.12 U vs.2.75±0.78 U,P<0.05).The LT group showed less cellular edema,inflammation and few damaged mitochondria as compared with the NT group.CONCLUSION:These data suggested that infusing 4 °C NS continuously after ROSC could quickly lower the core body temperature,while maintaining a stable hemodynamic state and balancing oxygen metabolism,which protect the liver in terms of biochemistry,enzymology and histology after CPR.展开更多
AIM:To investigate the effect of hypothermia on the function of the liver remnant(LR)after extended hepatectomy.METHODS:We performed a 75% partial hepatectomy(PH)in male C57BL/6J mice.Body temperature was measured wit...AIM:To investigate the effect of hypothermia on the function of the liver remnant(LR)after extended hepatectomy.METHODS:We performed a 75% partial hepatectomy(PH)in male C57BL/6J mice.Body temperature was measured with a rectal probe.The study mice were prospectively grouped as hypothermic(HT)or normothermic(NT)if their body temperature was < 34 ℃ vs≥ 34 ℃,respectively.Blood and liver samples were obtained at 24 and 48 h after 75% PH.Various factors during and after 75% PH were compared at each time point and the most important factor for a good outcome after 75% PH was determined.RESULTS:At 24 and 48 h after 75% PH,LR weight was decreased in HT mice compared with that in NT mice and the assay results in the HT mice were consistent with liver failure.NT mice had normal liver regeneration.Each intra-and post-operative factor which showed statistical significance in univariate analysis was evaluated by multivariate analysis.The most important factor for a good outcome after 75% PH was body temperature at both 24 and 48 h after surgery.CONCLUSION:Hypothermia after an extensive hepatectomy predicts impending liver failure and may be a useful clinical marker for early detection of liver failure after extended hepatectomy.展开更多
Background: The potential benefits of implantable cardioverter-defibrillator (ICD) therapy in patients with sudden cardiac death (SCD) treated with therapeutic hypothermia (TH) have not been well studied. Methods: Inc...Background: The potential benefits of implantable cardioverter-defibrillator (ICD) therapy in patients with sudden cardiac death (SCD) treated with therapeutic hypothermia (TH) have not been well studied. Methods: Incidence of recurrent non-sustained ventricular arrhythmia, ICD therapy, and death were ascertained in 64 consecutive survivors of SCD due to ventricular fibrillation or tachycardia, who were treated with TH. Follow-up was 31.5 +/- 3.3 months in 41 ICD recipients and 36.3 +/- 3.9 months in 23 patients who did not receive an ICD due to the presence of a reversible cause of cardiac arrest, an acute myocardial infarction in 87%. Results: Combined incidence of ventricular arrhythmia, ICD therapy, or death in patients who underwent ICD placement (21.9%) were similar to overall mortality in the patients who did not receive an ICD (21.7%, p = 0.752). ICD placement was associated with a significant mortality benefit;95.1% survival in ICD recipients vs. 78.3% in the no-ICD group (p = 0.038). Electrocardiographic findings of ST segment elevation on admission were associated with increased event rate in ICD recipients (p = 0.039) and increased mortality in SCD patients who did not receive an ICD (p Conclusions: SCD survivors treated with TH are at increased risk for recurrent arrhythmic events and derive significant mortality benefit from ICD implantation. Increased mortality in revascularized SCD patients with acute coronary syndrome, thought to have a reversible cause of cardiac arrest, calls for prospective trials investigating utility of ICD in this vulnerable patient population.展开更多
Objective Recent studies in neonatal animals have shown that even slightly decreasing in brain or core temperature could ameliorate the damage resulting from hypoxic-ischemia insults. But the influence of hypother- mi...Objective Recent studies in neonatal animals have shown that even slightly decreasing in brain or core temperature could ameliorate the damage resulting from hypoxic-ischemia insults. But the influence of hypother- mia which had been used after the end of hypoxia-ischemia of the model hypoxia-ischemia brain damage(HIBD)was unknown. This research wanted to investigate whether hypothermia of defferent begin time after HIBD still could pro- tect the brain in neonatal rats. Methods Pericranial temperatures were adjusted to 31℃ in neonatal rats immediate- ly or 2h after the end of hypoxia-ischemia(HI),the number of apoptosis cells in HIBD rats’ brain had been counted, rat pups’ storing food ability had been observed. Results Apoptosis increased obviously when rat pups were 8 days old, whlie hypothermia reduced apoptosis,and postponed apoptosis expression in group that 31 ℃ hypothermia was used immediately or 1h after the end of HI,and hypothermia improved the rat pups’ storing food ability. This effect was more obviously in the group that hypothermia was used immediately after the HI than in the group that hypother- mia was used 1h after the HI. But the protective effect was not clear in the group that hypothermia was used 2h after the HI. Conclusion Hypothermia which was used within 1h after the end of HI could protect the HIBD neonatal rat pups brain, this effect was more obviously in the hypothermia be used early after the end of HI group than in the hy- pothermia be used late after the end of HI group.展开更多
Used for over 3600 years, hypothermia, or targeted temperature management(TTM), remains an ill defined medical therapy. Currently, the strongest evidence for TTM in adults are for out-of-hospital ventricular tachycard...Used for over 3600 years, hypothermia, or targeted temperature management(TTM), remains an ill defined medical therapy. Currently, the strongest evidence for TTM in adults are for out-of-hospital ventricular tachycardia/ventricular fibrillation cardiac arrest, intracerebral pressure control, and normothermia in the neurocritical care population. Even in these disease processes, a number of questions exist. Data on disease specific therapeutic markers, therapeutic depth and duration, and prognostication are limited. Despite ample experimental data, clinical evidence for stroke, refractory status epilepticus, hepatic encephalopathy, and intensive care unit is only at the safety and proof-of-concept stage. This review explores the deleterious nature of fever, the theoretical role of TTM in the critically ill, and summarizes the clinical evidence for TTM in adults.展开更多
基金The study was approved by the Institutional review board of The Affiliated Hospital of Southwest Medical University,No.KY2023184.
文摘BACKGROUND Perioperative hypothermia(PH)negatively affects the physical and mental health of patients to varying degrees.Currently,there is no effective multidisciplinary team(MDT)intervention for gynecological patients with PH.AIM To apply the best evidence on the prevention and management of PH in gynecological patients,improve the quality of perioperative evidence-based care based on treatment by an MDT for gynecological patients and analyze the effect of MDT-and evidence-based practice(EBP)projects on the psychological status and cognitive function of gynecological patients with PH.METHODS Under the guidance of knowledge translation and combined with the opinions of involved stakeholders and clinical experts,the best evidence for PH prevention and management in gynecological patients was selected and adjusted to suit the practice setting.Based on the evidence,the practice plan was developed,and the MDT intervention was carried out in the preoperative ward,the preoperative preparation room,the intraoperative operating room,the postanesthesia care unit,and the 24-hour postoperative gynecological ward through the EBP program.The incidence of hypothermia,the nurses’awareness,the implementation rate of examination indicators,and the thermal comfort level,psychological status and cognitive function of patients were compared before and after the implementation of the program.RESULTS The incidence of PH in gynecological patients decreased from 43.33%to 13.33%after the implementation of the scheme.The implementation rate of examination indicators 6-10,12,14,16-18,21,and 22 reached 100%,and that of other indicators was above 90%,except for examination indicators 5 and 13,which was 66.67%;the indices were significantly improved compared with the baseline(before evidence application)(P<0.05).The score of nurses'awareness of PH prevention and management in gynecological patients increased from 60.96±9.70 to 88.08±8.96,and the difference was statistically significant(P<0.001).The total score of the perioperative thermal comfort level of patients undergoing gynecological surgery was 27.97±2.04,which was significantly increased compared with the score of 21.27±1.57 observed by researchers at baseline(P<0.001).The perioperative Hamilton Depression Scale and Hamilton Anxiety Scale scores of patients undergoing gynecological surgery decreased from 15.03±3.16 and 13.93±2.64 to 4.30±1.15 and 3.53±0.78,respectively,with statistically significant differences(P<0.001).The perioperative Montreal Cognitive Assessment Scale score of the gynecological surgery patients increased from 23.17±1.68 to 26.93±1.11,also with statistical significance(P<0.001).CONCLUSION MDT-based EBP for PH prevention and management in gynecological patients during the perioperative period can standardize nursing operations,improve nurses'awareness and behavioral compliance with gynecological hypothermia management,and reduce the occurrence of PH in gynecological patients while playing a positive role in reducing patients’negative emotions and enhancing their cognitive function.
文摘Background: Moderate to severe hypoxic-ischemic encephalopathy (HIE) in neonates is often treated with hypothermia. However, some neonates may experience epileptic seizures during therapeutic hypothermia (TH). Data on the electrophysiologic and evolutionary aspects of these seizures are scarce in African countries. Objectives: To determine the types of epileptic seizures caused by HIE in neonates in Brazzaville;to describe the evolution of background EEG activities during TH and rewarming;to report the evolution of epileptic seizures. Methods: This was a cross-sectional, descriptive study conducted from January 2020 to July 2022. It took place in Brazzaville in the Neonatology Department of the Blanche Gomez Mother and Child Hospital. It focused on term neonates suffering from moderate or severe HIE. They were treated with hypothermia combined with phenobarbital for 72 hours. Results: Among 36 neonates meeting inclusion criteria, there were 18 boys and 18 girls. Thirty-one (86.1%) neonates had grade 2 and 5 (13.9%) grade 3 HIE. In our neonates, HIE had induced isolated electrographic seizures (n = 11;30.6%), electroclinical seizures (n = 25;69.4%), and 6 types of background EEG activity. During TH and rewarming, there were 52.8% of patients with improved background EEG activity, 41.7% of patients with unchanged background EEG activity, and 5.5% of patients with worsened background EEG activity. At the end of rewarming, only 9 (25%) patients still had seizures. Conclusion: Isolated electrographic and electroclinical seizures are the only pathological entities found in our studied population. In neonates with moderate HIE, the applied therapeutic strategy positively influences the evolution of both seizures and background EEG activity. On the other hand, in neonates with severe HIE, the same therapeutic strategy is ineffective. .
基金supported by The Health Research Council of New Zealand(grant No.16/003,17/601)the Marsden Fund(grant No.17-UOA232)a Sir Charles Hercus Fellowship from the Health Research Council of New Zealand(grant No.16/003)
文摘Perinatal hypoxic-ischemic encephalopathy is a leading cause of neonatal death and disability.Therapeutic hypothermia significantly reduces death and major disability associated with hypoxic-ischemic encephalopathy;however,many infants still experience lifelong disabilities to movement,sensation and cognition.Clinical guidelines,based on strong clinical and preclinical evidence,recommend therapeutic hypothermia should be started within 6 hours of birth and continued for a period of 72 hours,with a target brain temperature of 33.5 ±0.5℃ for infants with moderate to severe hypoxic-ischemic encephalopathy.The clinical guidelines also recommend that infants be re warmed at a rate of 0.5℃ per hour,but this is not based on strong evidence.There are no randomized controlled trials investigating the optimal rate of rewarming after therapeutic hypothermia for infants with hypoxic-ischemic encephalopathy.Preclinical studies of rewarming are conflicting and results were confounded by treatment with sub-optimal durations of hypothermia.In this review,we evaluate the evidence for the optimal start time,duration and depth of hypothermia,and whether the rate of rewarming after treatment affects brain injury and neurological outcomes.
基金supported by the Natural Science Foundation of Shandong Province of China,No.ZR2015HM023(to MSW)the Science and Technology Plan Project of Qingdao City of China,No.19-6-1-50-nsh(to MSW)
文摘Selective brain hypothermia is considered an effective treatment for neuronal injury after stroke,and avoids the complications of general hypothermia.However,the mechanisms by which selective brain hypothermia affects mitochondrial fission remain unknown.In this study,we investigated the effect of selective brain hypothermia on the expression of fission 1 (Fis1) protein,a key factor in the mitochondrial fission system,during focal cerebral ischemia/reperfusion injury.Sprague-Dawley rats were divided into four groups.In the sham group,the carotid arteries were exposed only.In the other three groups,middle cerebral artery occlusion was performed using the intraluminal filament technique.After 2 hours of occlusion,the filament was slowly removed to allow blood reperfusion in the ischemia/reperfusion group.Saline,at 4℃ and 37℃,were perfused through the carotid artery in the hypothermia and normothermia groups,respectively,followed by restoration of blood flow.Neurological function was assessed with the Zea Longa 5-point scoring method.Cerebral infarct volume was assessed by 2,3,5-triphenyltetrazolium chloride staining,and apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining.Fis1 and cytosolic cytochrome c levels were assessed by western blot assay.Fis1 mRNA expression was assessed by quantitative reverse transcription-polymerase chain reaction.Mitochondrial ultrastructure was evaluated by transmission electron microscopy.Compared with the sham group,apoptosis,Fis1 protein and mRNA expression and cytosolic cytochrome c levels in the cortical ischemic penumbra and cerebral infarct volume were increased after reperfusion in the other three groups.These changes caused by cerebral ischemia/reperfusion were inhibited in the hypothermia group compared with the normothermia group.These findings show that selective brain hypothermia inhibits Fis1 expression and reduces apoptosis,thereby ameliorating focal cerebral ischemia/reperfusion injury in rats.Experiments were authorized by the Ethics Committee of Qingdao Municipal Hospital of China (approval No.2019008).
文摘Objective:To find out whether warm bladder irrigation fluid can decrease the occurrence of perioperative hypothermia,blood loss and shiver in patients treated with benign prostatic hyperplasia(BPH).Method:A comprehensive literature review and meta-analysis that included randomized controlled trials(RCTs)related to temperature of irrigation fluid in the perioperative treatment for BPH was taken by researchers.The relevant literature were searched in Chinese database,such as Retrieval Chinese Journal Full-text Database,VIP Journal Database,Wanfang database,as well as in English search engine and database,including Embase,Cochrane and Medline till January 2018.The study quality was assessed by recommended standards from Cochrane Handbook(version 5.1.0).Results:A total of 28 RCTs and 3858 patients were included.The results showed that the incidences of shiver(risk ratio[RR]Z 0.32,95%confidence interval[CI]:0.28e0.36,p<0.001,I^2 Z 0%)and hypothermia(RR Z 0.36,95%CI:0.21e0.59,p<0.001,I^2 Z 67%)in the group of warm irrigation fluid were lower than the group having room-temperature fluid.Room-temperature irrigation fluid group caused a greater drop in body temperature compared to warm irrigation fluid group(p<0.001,I^2 Z 96%).We performed a narrative descriptive statistics only because of substantial heterogeneity.Conclusions:Warm bladder irrigation fluid can decrease the drop of body temperature and the incidence of hypothermia and shiver during and after the operation for BPH.Warm irrigation fluid should be considered as a standard practice in BPH surgeries.
文摘AIM: To assess the safety of therapeutic hypothermia(TH) concerning arrhythmias we analyzed serial electrocardiograms(ECG) during TH.METHODS: All patients recovered from a cardiac arrest with Glasgow < 9 at admission were treated with induced mild TH to 32-34℃. TH was obtained with cool fluid infusion or a specific intravascular device. Twelvelead ECG before,during,and after TH,as well as ECG telemetry data was recorded in all patients. From a total of 54 patients admitted with cardiac arrest during the study period,47 patients had the 3 ECG and telemetry data available. ECG analysis was blinded and performed with manual caliper by two independent cardiologists from blinded copies of original ECG,recorded at 25 mm/s and 10 mm/m V. Coronary care unit staff analyzed ECG telemetry for rhythm disturbances. Variables measured in ECG were rhythm,RR,PR,QT and corrected QT(QTc by Bazett formula,measured in lead v2) intervals,QRS duration,presence of Osborn's J wave and U wave,as well as ST segment displacement and T wave amplitude in leads Ⅱ,v2 and v5.RESULTS: Heart rate went down an average of 19 bpm during hypothermia and increased again 16 bpm with rewarming(P < 0.0005,both). There was a nonsignificant prolongation of the PR interval during TH and a significant decrease with rewarming(P = 0.041). QRS duration significantly prolonged(P = 0.041) with TH and shortened back(P < 0.005) with rewarming. QTc interval presented a mean prolongation of 58 ms(P < 0.005) during TH and a significant shortening with rewarming of 22.2 ms(P = 0.017). Osborn or J wave was found in 21.3% of the patients. New arrhythmias occurred in 38.3% of the patients. Most frequent arrhythmia was non-sustained ventricular tachycardia(19.1%),followed by severe bradycardia or paced rhythm(10.6%),accelerated nodal rhythm(8.5%) and atrial fibrillation(6.4%). No life threatening arrhythmias(sustained ventricular tachycardia,polymorphic ventricular tachycardia or ventricular fibrillation) occurred during TH. CONCLUSION: A 38.3% of patients had cardiac arrhythmias during TH but without life-threatening arrhythmias. A concern may rise when inducing TH to patients with long QT syndrome.
基金supported by the Major Project for Equipment Development of PLA in 2013(ASY135001)the National High Technology Research and Development Program of China(2015AA020312)
文摘Background: The successful treatment of military combat casualties with penetrating injuries is significantly dependent on the time needed to get the patient to an adequate treatment facility. Profound hypothermia induced suspended animation for delayed resuscitation(SADR) is a novel approach for inducing cardiac arrest and buying additional time for such injuries. However, the time used to safely administer circulatory arrest(CA) is controversial. The goal of this study was to evaluate the safety of hypothermia-induced SADR over 90 and 120 min time intervals.Methods: Sixteen male BAMA minipigs were randomized into two groups: CA90 group(90 min, n =8) and CA120 group(120 min, n =8). Cannulation of the right common carotid arteries and internal jugular veins was performed to establish cardiopulmonary bypass for each animal. Through the perfusion of cold organ preservation solution(OPS), cardioplegia and profound hypothermia(15℃) were induced. After CA, cardiopumonary bypass(CPB) was restarted, and the animals were gradually re-warmed and resuscitated. The animals were assisted with ventilators until spontaneous breathing was achieved. The index of hemodynamic perioperative serum chemistry values [alanine transaminase(ALT), aspartate aminotransferase(AST), creatinine(CR), lactic dehydrogenase(LDH) and troponin T(TnT)] and survival were observed from pre-operation to 7 days post-operation.Results: Fifteen animals were enrolled in the experiment, while 1 animal in CA120 group died from surgical error. All 8 animals in CA90 group recovered, with only 1 animal displaying mild disability. However, in CA120 group, only 2 animals survived with severe disability, and the other 5 animals died after 2 days post-operation. In CA90 group, the perioperative serum chemistry values increased at 1 day post-operation(ALT 84.43±18.65 U/L; AST 88.99±23.19 U/L; Cr 87.90±24.49μmol/L; LDH 1894.13±322.26 U/L; TnT 0.849±0.135 ng/ml) but decreased to normal or almost normal levels at 7 days post-operation(ALT 52.48±9.04 U/L; AST 75.23±21.46 U/L; Cr 82.69±18.41μmol/L; LDH 944.67±834.32 U/L; TnT 0.336±0.076 ng/ml).Conclusion: Profound hypothermia-induced SADR is an effective method for inducing cardiac arrest. Our results indicate that inducing CA for 90 min(at 15℃) is safer than doing so for 120 min. Our results indicate that 120 min of CA at 15℃ is dangerous and can result in high mortality and severe neurological complications. Further experimentation is needed to determine whether 120 min of CA at temperatures lower than 15℃ can lead to safe recovery.
基金supported by a grant from a science andtechnology project"Health of Science and Education"of Suzhouin 2013(KJXW2013026)
文摘BACKGROUND: Cardiac arrest(CA) is a common and serious event in emergency medicine. Despite recent improvements in resuscitation techniques, the survival rate of patients with CA is unchanged. The present study was undertaken to observe the effect of mild hypothermia(MH) on the reactive oxygen species(ROS) and the effect of neurological function and related mechanisms.METHODS: Sixty-five healthy male Sprague Dawley(SD) adult rats were randomly(random number) divided into 2 groups: blank control group(n=5) and CPR group(n=60). CA was induced by asphyxia. The surviving rats were randomly(random number) divided into two groups: normothermia CPR group(NT) and hypothermia CPR group(HT). Normothermia of 37 °C was maintained in the NT group after return of spontaneous circulation(ROSC), hypothermal intervention of 32 °C was carried out in the HT group for 4 hours immediately after ROSC. Both the NT and HT groups were then randomly divided into 2 subgroups 12 hours and 24 hours after ROSC(NT-12, NT-24, HT-12, HT-24 subgroups). During observation, the neurological defi cit scores(NDSs) was recorded, then the bilateral hippocampi were obtained from rats' head, and monoplast suspension of fresh hippocampus tissue was made immediately to determine the level of intracellular ROS by flow cytometry. Transmission electron microscope was used to observe the ultramicro changes of cellular nucleus and mitochondria. Reverse transcription-polymerase chain reaction(RT-PCR) was used to determine the expression of caspase-3 m RNA, and western-blotting(WB) was used to determine the level of LC3 in frozen hippocampus tissue. Measured data were analyzed with paired sample t test and One-Way ANOVA.RESULTS: Of 60 rats with CA, 44(73%) were successfully resuscitated and 33(55%) survived until the end of the experiment. The NDSs of rats in the NT and HT groups were more signifi cantly reduced than those in the BC group(F=8.107, P<0.05), whereas the NDSs of rats in the HT-12 and HT-24 subgroups were significantly increased in comparison with those NDSs of rats in the NT-12 and NT-24 subgroups, respectively(t=9.692, P<0.001; t=14.374, P<0.001). The ROS in hippocampus nerve cells in the NT and HT groups signifi cantly increased compared to the BC group(F=16.824, P<0.05), whereas the ROS in the HT-12 and HT-24 subgroups significantly reduced compared with that ROS in the NT-12 and NT-24 subgroups, respectively(t=9.836, P<0.001; t=7.499, P<0.001). The expression of caspase-3 m RNA in hippocampus nerve cells in the NT and HT groups were signifi cantly increased compared to the BC group(F=24.527, P<0.05), whereas the expression of caspase-3 m RNA in rats of the HT-12 and HT-24 subgroups was signifi cantly reduced compared to the NT-12 and NT-24 subgroups, respectively(t=6.935, P<0.001; t=4.317, P<0.001). The expression of LC3B-II/I in hippocampus nerve cells of rats in the NT and HT groups signifi cantlyincreased compared to the BC group(F=6.584, P<0.05), whereas the expression of LC3B-II/I in rats of the HT-12 and HT-24 subgroups significantly reduced compared to the NT-12 and NT-24 subgroups, respectively(t=10.836, P<0.001; t=2.653, P=0.02). Ultrastructure damage of nucleus and mitochondria in the NT group was more evident than in the BC group, and eumorphism of nucleus and mitochondria were maintained in rats of the HT group compared with the NT group.CONCLUSION: Mild hypothermia lessened the injury of nerve cells and improved the neurological function of rats that survived from cardiac arrest by reducing the ROS production of nerve cells and inhibiting the expression of caspase-3 m RNA and LC3, leading to cellular apoptosis and massive autophagy in rats that survived from cardiac arrest after CPR.
文摘Background: Existing studies have found that some inflammatory factors cause brain cell damage through the TLR4/NF-κB pathway, and that mild hypothermia has a protective effect on nerve cells. It is not clear whether the mild hypothermic brain protection is achieved through the TLR4/NF-κB pathway in microglia. Objective: To investigate the impacts of mild hypothermia on lipopolysaccharide (LPS)-mediated TLR4/NF-κB signaling pathway in microglia. Method: The cultured microglia cells in vitro were divided into the NS group and the LPS group at 33?C and 37?C, respectively;quantitative RT-PCR was performed to detect the expressions of TLR4 and NF-κB mRNA in the microglia, Western blot was used to detect the expressions of TLR4 and NF-κB protein in the microglia, and ELISA was performed to detect the levels of tumor necrosis factor α (TNF-α) and interleukin-10 (IL-10) in the culture medium. Results: Under the LPS stimulation, the mRNA and protein expressions of TLR4 and NF-κB at different time points had significant changes between the normothermia group and the mild hypothermia group, in which the expressions in the former group were firstly increased and then decreased, while those in the latter showed a continuous increasing trend (P < 0.01);and the expressions of TNF-α in all the groups presented the trend of first-increasing then-decreasing, while IL-10 exhibited one slow linear increasing trend (P Conclusions: Mild hypothermia could inhibit the mRNA and protein expressions of LPS-mediated TLR4/NF-κB signaling pathway in the microglia, and inhibit the production and release of downstream inflammatory cytokines (TNF-α and IL-10).
文摘BACKGROUND:Induction of hypothermia(a 4℃decrease from baseline)improves outcomes in adult cardiac arrest and neonatal hypoxic ischemic encephalopathy,and may benefit other conditions as well.Methods used to implement or prevent hypothermia typically require skin contact with blankets or pads or intravascular access with catheter devices.The study was to evaluate the potential to induce mild therapeutic hypothermia via an esophageal route in a porcine model.METHODS:Single-animal proof-of-concept study of a prototype esophageal device in a 70 kg Yorkshire swine.We measured the rate of temperature change after placement of a prototype device to induce hypothermia via the esophagus,and compared this rate to known temperature changes that occur under similar laboratory conditions without a hypothermic device.RESULTS:Swine temperature decreased from a starting temperature of 37.8℃to 33.8℃(achieving the goal of a 4℃decrease)in 175 minutes,resulting in a cooling rate of 1.37℃/h.Histopathology of the esophagus showed normal tissue without evidence of injury.CONCLUSION:A prototype of an esophageal cooling device induced hypothermia effectively in a large single-swine model.
基金supported by a grant from 11th Five-Year Plan Medical Science Scientific Research Fund of the Chinese People's Liberation Army(08G002)
文摘BACKGROUND:Hypothermia is associated with poor outcome in trauma patients;however,hemorrhagic shock(HS)model with anesthetized swine was different from that of clinical reality.To identify the effects of environmental hypothermia on HS,we investigated hemodynamics and oxygen dynamics in an unanesthetized swine model of HS under simulating hypothermia environment.METHODS:Totally 16 Bama pigs were randomly divided into ambient temperature group(group A)and low temperature group(group B),8 pigs in each group.Venous blood(30 mL/kg)was continuously withdrawn for more than 15 minutes in conscious swine to establish a hemorrhagic shock model.Pulmonary arterial temperature(Tp),heart rate(HR),mean arterial pressure(MAP),pulmonary arterial pressure(PAP),pulmonary arterial wedge pressure(PAWP),central venous pressure(CVP),cardiac output(CO),hemoglobin(Hb),saturation of mixed venous blood(SvO_2)and blood gas analysis were recorded at the baseline and different hemorrhagic shock time(HST).The whole body oxygen delivery indices,DO_2l and VO_2l,and the O_2 extraction ratio(O_2ER)were calculated.RESULTS:Core body temperature in group A decreased slightly after the hemorrhagic shock model was established,and environmental hypothermia decreased in core body temperature.The mortality rate was significantly higher in group B(50%)than in group A(0%).DO_2l and VO_2l decreased significantly after hemorrhage.No difference was found in hemodynamics,DO_2l and VO_2l between group A and group B,but the difference in pH,lactic acid and O_2ER was significant between the two groups.CONCLUSION:Environmental hypothermia aggravated the disorder of oxygen metabolism after hemorrhagic shock,which was associated with poor prognosis.
文摘BACKGROUND:Good neurological outcome after cardiac arrest(CA) is hard to achieve for clinicians.Experimental and clinical evidence suggests that therapeutic mild hypothermia is beneficial.This study aimed to assess the effectiveness and safety of therapeutic mild hypothermia in patients successfully resuscitated from CA using a meta-analysis.METHODS:We searched the MEDLINE(1966 to April 2012),OVID(1980 to April 2012),EMBASE(1980 to April 2012),Chinese bio-medical literature & retrieval system(CBM)(1978 to April 2012),Chinese medical current contents(CMCC)(1995 to April 2012),and Chinese medical academic conference(CMAC)(1994 to April 2012).Studies were included if 1) the study design was a randomized controlled trial(RCT);2) the study population included patients successfully resuscitated from CA,and received either standard post-resuscitation care with normothermia or mild hypothermia;3) the study provided data on good neurologic outcome and survival to hospital discharge.Relative risk(RR) and 95%confidence interval(CI) were used to pool the effect.RESULTS:The study included four RCTs with a total of 417 patients successfully resuscitated from CA.Compared to standard post-resuscitation care with normothermia,patients in the hypothermia group were more likely to have good neurologic outcome(RR=1.43,95%CI 1.14-1.80,P=0.002) and were more likely to survive to hospital discharge(RR=1.32,95%CI 1.08-1.63,P=0.008).There was no significant difference in adverse events between the normothermia and hypothermia groups(P>0.05),nor heterogeneity and publication bias.CONCLUSION:Therapeutic mild hypothermia improves neurologic outcome and survival in patients successfully resuscitated from CA.
文摘Aim: The relationship between preoperative anxiety level and intraoperative hypothermia (<36℃) was investigated. Background: Core temperature often decreases during surgery, with an initial rapid decrease followed by a slower decrease for about 2 hours. Preoperative anxiety may influence perioperative physiological responses. The relationship between preoperative anxiety level and perioperative decrease in core temperature has not been studied closely. Design: A prospective observational study. Methods: This study enrolled 120 adult patients who underwent elective major abdominal surgery under combined epidural and general anesthesia. Tympanic membrane temperature was used to measure core temperature preoperatively and during the operation. The relationship between anxiety level according to the State-Trait Anxiety Inventory (STAI) and core temperature was examined using descriptive and multivariate risk analysis. Results: High anxiety level was found in 61 patients (51%), of which 26 (43%) developed hypothermia during the first hour and 40 (66%) developed hypothermia during the first 2 hours of anesthesia. After adjustment for covariates, patients with a high anxiety level were found to have a 2.17-fold higher risk of hypothermia during the first hour and a 1.77-fold higher risk of hypothermia during the first 2 hours than patients with a low/moderate anxiety level. Conclusions: The risk of hypothermia in the early phase of general anesthesia can be predicted by measurement of the preoperative anxiety level using the STAI. Relevance to Clinical Practice: Patients with a high anxiety level had a significantly higher risk of intraoperative hypothermia. Preoperative preventive nursing care programs should include anxiety management and thermal care.
文摘We have used a nonlinear one-dimensional heat transfer model based on temperature-dependent blood perfusion to predict temperature distribution in dermis and subcutaneous tissues subjected to point heating sources. By using Jacobi elliptic functions, we have first found the analytic solution corresponding to the steady-state temperature distribution in the tissue. With the obtained analytic steady-state temperature, the effects of the thermal conductivity, the blood perfusion, the metabolic heat generation, and the coefficient of heat transfer on the temperature distribution in living tissues are numerically analyzed. Our results show that the derived analytic steady-state temperature is useful to easily and accurately study the thermal behavior of the biological system, and can be extended to such applications as parameter measurement, temperature field reconstruction and clinical treatment.
文摘Therapeutic hypothermia is today used in several clinical settings, among them the gut related diseases that are influenced by ischemia/reperfusion injury. This perspective paved the way to the study of hibernation physiology, in natural hibernators, highlighting an unexpected importance of the gut microbial ecosystem in hibernation and torpor. In natural hibernators, intestinal microbes adaptively reorganize their structural configuration during torpor, and maintain a mutualistic configuration regardless of long periods of fasting and cold temperatures. This allows the gut microbiome to provide the host with metabolites, which are essential to keep the host immunological and metabolic homeostasis during hibernation. The emerging role of the gut microbiota in the hibernation process suggests the importance of maintaining a mutualistic gut microbiota configuration in the application of therapeutic hypothermia as well as in the development of new strategy such as the use of synthetic torpor in humans. The possible utilization of tailored probiotics to mold the gut ecosystem during therapeutic hypothermia can also be taken into consideration as new therapeutic strategy.
文摘BACKGROUND:The study aimed to explore the effects of hypothermia state induced by4 ℃ normal saline(NS) on liver biochemistry,enzymology and morphology after restoration of spontaneous circulation(ROSC) by cardiopulmonary resuscitation(CPR) in swine.METHODS:After 4 minutes of ventricular fibrillation(VF),standard CPR was carried out.Then the survivors were divided into two groups:low temperature group and normal temperature group.The low temperature(LT) group(n-5) received continuously 4 °C NS at the speed of 1.33 mL/kg per minute for 22 minutes,then at the speed lowering to 10 mL/kg per hour.The normal temperature(NT) group(n-5) received NS with normal room temperature at the same speed of the LT group.Hemodynamic status and oxygen metabolism were monitored and the levels of serum alanine aminotransferase(ALT),aspartate aminotransferase(AST) and lactate dehydrogenase(LDH) were measured in blood samples obtained at baseline and at 10 minutes,2 hours and 4 hours after ROSC.At 24 hours after ROSC,the animals were killed and the liver was removed to determine the Na^+-K^+-ATPase and Ca^(2+)-ATPase enzyme activities and histological changes under a light or electron microscope.RESULTS:Core temperature was decreased in the LT group(P<0.05),while HR,MAP and CPP were not significantly decreased(P>0.05) compared with the NT group(P>0.05).The oxygen extraction ratio was lower in the LT group than in the NT group(P<0.05).The serum levels of ALT,AST and LDH increased in both groups but not significantly in the LT group.The enzyme activity of liver ATP was much higher in the LT group(Na^+-K^+-ATP enzyme:8.64±3.32 U vs.3.28±0.71 U;Ca^(2+)-ATP enzyme:10.92±2.12 U vs.2.75±0.78 U,P<0.05).The LT group showed less cellular edema,inflammation and few damaged mitochondria as compared with the NT group.CONCLUSION:These data suggested that infusing 4 °C NS continuously after ROSC could quickly lower the core body temperature,while maintaining a stable hemodynamic state and balancing oxygen metabolism,which protect the liver in terms of biochemistry,enzymology and histology after CPR.
基金Supported by NIH DK064361,NIH R01NS051646 and the Deason Foundation,to Nguyen JHthe Uehara Memorial Foundation,No. 200940051,to Hori T
文摘AIM:To investigate the effect of hypothermia on the function of the liver remnant(LR)after extended hepatectomy.METHODS:We performed a 75% partial hepatectomy(PH)in male C57BL/6J mice.Body temperature was measured with a rectal probe.The study mice were prospectively grouped as hypothermic(HT)or normothermic(NT)if their body temperature was < 34 ℃ vs≥ 34 ℃,respectively.Blood and liver samples were obtained at 24 and 48 h after 75% PH.Various factors during and after 75% PH were compared at each time point and the most important factor for a good outcome after 75% PH was determined.RESULTS:At 24 and 48 h after 75% PH,LR weight was decreased in HT mice compared with that in NT mice and the assay results in the HT mice were consistent with liver failure.NT mice had normal liver regeneration.Each intra-and post-operative factor which showed statistical significance in univariate analysis was evaluated by multivariate analysis.The most important factor for a good outcome after 75% PH was body temperature at both 24 and 48 h after surgery.CONCLUSION:Hypothermia after an extensive hepatectomy predicts impending liver failure and may be a useful clinical marker for early detection of liver failure after extended hepatectomy.
文摘Background: The potential benefits of implantable cardioverter-defibrillator (ICD) therapy in patients with sudden cardiac death (SCD) treated with therapeutic hypothermia (TH) have not been well studied. Methods: Incidence of recurrent non-sustained ventricular arrhythmia, ICD therapy, and death were ascertained in 64 consecutive survivors of SCD due to ventricular fibrillation or tachycardia, who were treated with TH. Follow-up was 31.5 +/- 3.3 months in 41 ICD recipients and 36.3 +/- 3.9 months in 23 patients who did not receive an ICD due to the presence of a reversible cause of cardiac arrest, an acute myocardial infarction in 87%. Results: Combined incidence of ventricular arrhythmia, ICD therapy, or death in patients who underwent ICD placement (21.9%) were similar to overall mortality in the patients who did not receive an ICD (21.7%, p = 0.752). ICD placement was associated with a significant mortality benefit;95.1% survival in ICD recipients vs. 78.3% in the no-ICD group (p = 0.038). Electrocardiographic findings of ST segment elevation on admission were associated with increased event rate in ICD recipients (p = 0.039) and increased mortality in SCD patients who did not receive an ICD (p Conclusions: SCD survivors treated with TH are at increased risk for recurrent arrhythmic events and derive significant mortality benefit from ICD implantation. Increased mortality in revascularized SCD patients with acute coronary syndrome, thought to have a reversible cause of cardiac arrest, calls for prospective trials investigating utility of ICD in this vulnerable patient population.
文摘Objective Recent studies in neonatal animals have shown that even slightly decreasing in brain or core temperature could ameliorate the damage resulting from hypoxic-ischemia insults. But the influence of hypother- mia which had been used after the end of hypoxia-ischemia of the model hypoxia-ischemia brain damage(HIBD)was unknown. This research wanted to investigate whether hypothermia of defferent begin time after HIBD still could pro- tect the brain in neonatal rats. Methods Pericranial temperatures were adjusted to 31℃ in neonatal rats immediate- ly or 2h after the end of hypoxia-ischemia(HI),the number of apoptosis cells in HIBD rats’ brain had been counted, rat pups’ storing food ability had been observed. Results Apoptosis increased obviously when rat pups were 8 days old, whlie hypothermia reduced apoptosis,and postponed apoptosis expression in group that 31 ℃ hypothermia was used immediately or 1h after the end of HI,and hypothermia improved the rat pups’ storing food ability. This effect was more obviously in the group that hypothermia was used immediately after the HI than in the group that hypother- mia was used 1h after the HI. But the protective effect was not clear in the group that hypothermia was used 2h after the HI. Conclusion Hypothermia which was used within 1h after the end of HI could protect the HIBD neonatal rat pups brain, this effect was more obviously in the hypothermia be used early after the end of HI group than in the hy- pothermia be used late after the end of HI group.
文摘Used for over 3600 years, hypothermia, or targeted temperature management(TTM), remains an ill defined medical therapy. Currently, the strongest evidence for TTM in adults are for out-of-hospital ventricular tachycardia/ventricular fibrillation cardiac arrest, intracerebral pressure control, and normothermia in the neurocritical care population. Even in these disease processes, a number of questions exist. Data on disease specific therapeutic markers, therapeutic depth and duration, and prognostication are limited. Despite ample experimental data, clinical evidence for stroke, refractory status epilepticus, hepatic encephalopathy, and intensive care unit is only at the safety and proof-of-concept stage. This review explores the deleterious nature of fever, the theoretical role of TTM in the critically ill, and summarizes the clinical evidence for TTM in adults.
