亚低温对兔心肺复苏后凝血及脑微循环的影响

目的 探讨亚低温治疗对兔心肺复苏后凝血异常及脑微循环血流变化的干预作用.方法 本实验在中山大学卫生部辅助循环重点实验室进行.24只成年新西兰大白兔随机(随机数字法)分为常温(normothermic,NT)治疗组和亚低温治疗(therapeutic hypothermia,TH)组,每组12只,采用交流电致颤的方式建立心肺复苏(CPR)模型,自主循环恢复后(ROSC)NT组动物置于室温下观察12 h,TH组动物采用体表降温的方法诱导亚低温,达到目标温度后维持12 h.所有动物CPR前及ROSC后4,8,12 h分别测定PT,APTT,INR,D-D,血小板计数(BPC);测定抗凝血酶Ⅲ活性(AT-Ⅲ)和血浆蛋白C活性(PC);用PERIMED Multichannel Laser Doppler系统监测大脑皮层微循环血流.各组数据依据正态检验结果用单因素方差分析或秩和检验,多重比较用LSD-t检验,两样本均数的比较用成组t检验,相关性采用Pearson相关性分析,以P＜0.05为差异具有统计学意义.结果 NT组动物ROSC后PT,APTT,INR逐渐缩短的趋势,ROSC后12 h APTT明显短于基础值(P=0.025),而AT-Ⅲ和PC活性显著下降.和NT组相比,TH组PT,APTT,INR值显著增大,差异具有统计学意义;但AT-Ⅲ,PC活性、D-D浓度,两组差异无统计学意义.CPR前、ROSC后4,8和12 h NT组大脑皮层血流分别(401.60±11.76),(258.86±34.58),(317.59±23.36)和(371.98±5.79)mL/min,TH组为398.18±12.91.336.19±19.27,347.76±13.80和383.78±3.29 mL/min.ROSC后各时间点TH组大脑皮层血流量明显高于NT组(4 h:t=-6.025,df=16,P=0.000;8 h:t=-2.942,df=12,P=0.012;12 h:t=-3.959,df=8,P=0.004).Pearson相关分析显示ROSC后大脑皮层血流和APTT正相关(4 h:R=0.503,P=0.033;8 h:R=0.565,P=0.035;12 h:R=0.774,P=0.009),与其他凝血指标无关.结论 ROSC后亚低温治疗使凝血功能下降的同时伴随脑微循环血流的增加,CPR后亚低温治疗对ROSC后凝血失衡的影响可能是其发挥脑保护作用的机制之一.

Abstract：

Objective To study the effects of mild hypothermia (MH) on blood coagulation and cerebral microcirculation in rabbits after cardiopulmonary resuscitation (CPR). Method A total of 24 New Zealand rabbits were randomly (random number) divided equally into normothermic group (NT) and MH group. CPR model was established by ventricular fibrillation induced by using alternating current. The rabbits of NT group were observed for 12 h in room temperature after restoration of spontaneous circulation (ROSC). The mild hypothermia was induced in the rabbits of group MH by surface cooling after ROSC, and maintained for 12 h after the aimed low temperature reached. The PT (prothrombin time), APTT (activated partial thromboplastin time), INR (international normalized ratio of prothrombin), D-dimmer (DD) , blood platelet count (BPC) , anti-thrombin Ⅲ activity (AT-Ⅲ) and protein C activity (PC) were measured before CPR and 4 h, 8 h and 12 h after ROSC, and at the same time the cerebral microcirculation was measured by using PERIMED Multichannel Laser Doppler system. One-way ANOVA or Mann-Whitney rank was used to determine the statistical significance between two groups. LSD-t test was used for multiple comparisons,t test for comparisons of means between two independent samples, and Pearson correlation test for correlation analysis. Results The PT, APTT and INR showed a trend of gradually shortening during the course. The APTT in 12 h after ROSC was significantly shorter than that before CPR (23.32 ±5.19 vs. 29.53 ±5.10,P = 0.025), and the activity of AT- Ⅲ and PC were decreased significantly. Compared with the group NT,the PT, APTT and INR in group MH were increased significantly, while there were no differences in the activity of AT- Ⅲ, PC and D-D between two groups. The rates of cerebral microcirculation in group NT before CPR and 4 h, 8 h and 12 h after ROSC were 401.60 ± 11.76 mL/min, 258.86 ± 34. 58 mL/min,317.59 ± 23.36 mL/min and 371.98 ± 5.79 mL/min, respectively, and those in group MT were 398.18 ±12.91 mL/min, 336.19 ± 19.27 mL/min, 347.76 ± 13.80 mL/min and 383.78 ± 3.29 mL/min, respectively. There were significant differences between two groups at each interval after ROSC (4 h: t = - 6.025,df=16, P=0.000;8 h: t= -2.942, df=12, P=0.012;12 h: t= -3.959, df=8, P=0.004). The Pearson correlation test showed that the rate of cerebral microcirculation was positive correlated with APTT after ROSC (4 h:R =0.503,P=0.033;8 h:R=0. 565,P=0. 035;12 h:R=0. 774,P=0. 009), and was not correlated with the other blood coagulants. Conclusions The mild hypothermia led to the inhibition of blood coagulation and improved the cerebral microcirculation concomitantly, which may be one of the mechanism of cerebral protection.     

Therapeutic hypothermia after cardiopulmonary resuscitation

Full cerebral recovery after cardiopulmonary resuscitation is still a rare event. Unfortunately, up to now, no specific and outcome-improving therapy was available after such events. From several cases it is known that low body and brain temperature during a cardiocirculatory arrest improves the neurological outcome following these events. As it is not possible in acute events to induce hypothermia beforehand, whether cooling after the insult could also be protective was evaluated. After animal studies in the 1990s and first clinical pilot trials of mild therapeutic and induced hypothermia, two randomized trials of hypothermic therapy after successful resuscitation after cardiac arrest were conducted. These studies demonstrated that hypothermia after cardiac arrest could improve neurological outcome as well as overall mortality.     

Therapeutic hypothermia after cardiopulmonary resuscitation

Full cerebral recovery after cardiopulmonary resuscitation is still a rare event. Unfortunately, up to now, no specific and outcome-improving therapy was available after such events. From several cases it is known that low body and brain temperature during a cardiocirculatory arrest improves the neurological outcome following these events. As it is not possible in acute events to induce hypothermia beforehand, whether cooling after the insult could also be protective was evaluated. After animal studies in the 1990s and first clinical pilot trials of mild therapeutic and induced hypothermia, two randomized trials of hypothermic therapy after successful resuscitation after cardiac arrest were conducted. These studies demonstrated that hypothermia after cardiac arrest could improve neurological outcome as well as overall mortality.     

Effects of adenosine monophosphate on induction of therapeutic hypothermia and neuronal damage after cardiopulmonary resuscitation in rats

Background

Animal studies and pathophysiological considerations suggest that therapeutic hypothermia after cardiopulmonary resuscitation is the more effective the earlier it is induced. Therefore this study is sought to examine whether pharmacological facilitated hypothermia by administration of 5′-adenosine monophosphate (AMP) is neuroprotective in a rat model of cardiac arrest (CA) and resuscitation.

Methods

Sixty-one rats were subjected to CA. After 6 min of ventricular fibrillation advanced cardiac life support was started. After successful return of spontaneous circulation (ROSC, n = 40), animals were randomized either to placebo group (n = 14) or AMP group (800 mg/kg body weight, n = 14). Animals were kept at an ambient temperature of 18 °C for 12 h after ROSC and core body temperature was measured using a telemetry temperature probe. Neuronal damage was analyzed by counting Nissl-positive (i.e. viable) neurons and TUNEL-positive (i.e. apoptotic) cells in coronal brain sections 7 days after ROSC. Functional status evaluated on days 1, 3 and 7 after ROSC by a tape removal test.

Results

Time until core body temperature dropped to <34.0 °C was 31 min [28; 45] in AMP-treated animals and 125 min [90; 180] in the control group (p = 0.003). Survival until 7 days after ROSC was comparable in both groups. Also number of Nissl-positive cells (AMP: 1 [1; 7] vs. placebo: 2 [1; 3] per 100 pixel; p = 0.66) and TUNEL-positive cells (AMP: 56 [44; 72] vs. placebo: 53 [41; 67] per 100 pixel; p = 0.70) did not differ. Neither did AMP affect functional neurological outcome up to 7 days after ROSC. Mean arterial pressure 20 min after ROSC was 49 [45; 55] mmHg in the AMP group in comparison to 91 [83; 95] mmHg in the control group (p < 0.001).

Conclusion

Although application of AMP reduced the time to reach a core body temperature of <34 °C neither survival was improved nor neuronal damage attenuated. Reason for this is probably induction of marked hypotension as an adverse reaction to AMP treatment.     

兔心肺复苏后经腹腔诱导亚低温的研究

目的 探讨兔心肺复苏后经腹腔灌注低温液体能否诱导亚低温并评价其安全性.方法 实验一:15只成年新西兰兔依据灌注首剂4℃低温液体剂量的不同分为30,40,60,80和100 mL/ks5组,选择鼓膜温度卜降迅速、稳定的一组连接腹腔灌流装置(专利号Z1200820201265)维持亚低温12h,随后进行复温,并以该组的首剂剂量作为实验二的首剂量.观察血浆生化指标的变化和肝、小肠、肾组织的损伤情况.实验二:12只成年新西兰兔,用电致颤的方式建立心肺复苏(CPR)模型,自主循环恢复(ROSC)后向腹腔内灌入首剂4℃低温液体,达到目标温度后连接腹腔灌流装置维持业低温12h,观察生化指标的变化.腹腔灌液前后生化指标的比较用配对t检验,P<0.05为差异具有统计学意义.结果 实验一:兔腹腔内灌注80 mL/kg低温液体后鼓膜温度(30±2.00)min达到目标温度,通过腹腔灌流装置能稳定维持亚低温和缓慢复温,腹腔灌液后没有出现生化指标的紊乱和造成肝、肾、肠的组织学损伤.实验二:ROSC后兔腹腔内灌注80mL/kg 4℃低温液体后鼓膜温度(26.00±6.99)min达到目标温度,腹腔温度不足10min达到甘标温度,ROSC后腹腔内灌注4℃低温液体没有出现生化指标的紊乱.结论 兔心肺复苏后经腹腔灌注低温液体能安全、快速诱导亚低温.     

The effect of mild therapeutic hypothermia on renal function after cardiopulmonary resuscitation in men

Background: Mild therapeutic hypothermia (MTH) improves neurological outcome in patients after cardiac arrest. From animal and human studies it appears that hypothermia impairs renal function. The aim of this study was to examine the effects of MTH on renal function in humans. Methods: Patients were participants recruited in one of the centres of the hypothermia after cardiac arrest-multicenter trial. We measured serum creatinine and creatinine clearance (C_Cr) within 24 h of MTH, at 4 hourly intervals. Patients were followed for acute renal failure and need for renal supportive therapy for 28 days. Results: We included 60 patients (32 hypothermic, 28 normothermic). Median serum creatinine on admission was [{119 μmol/l (IQR 108–133)} {1.35 mg/dl (IQR 1.22–1.50)}] in hypothermic and [{114 μmol/l (IQR 99–131)} {1.29 mg/dl (IQR 1.12–1.48)}] in normothermic patients, and decreased to [{69 μmol/l (IQR 62–84)} {0.78 mg/dl (IQR 0.70–0.95)}] in the hypothermic group and to [{88 μmol/l (IQR 71–123)} {1.00 mg/dl (IQR 0.80–1.39)}] in the normothermic group within 24 h. C_Cr was decreased on admission. Within 24 h C_Cr improved to normal values in normothermic patients [1.53 ml/s (IQR 1.15–2.35) {92 ml/min (IQR 69–141)}] and remained low in hypothermic patients [0.88 ml/s (IQR 0.63–1.38) {53 ml/min (IQR 38–83)}] (P=0.0006). No difference was found between the groups in the development of acute renal failure or the need for renal supportive therapy. Conclusion: Twenty four hours of MTH was associated with a delayed improvement in renal function. This was not reflected in the serum creatinine values, which were low in the hypothermic group. This transient impaired renal function appeared to be completely reversible within 4 weeks.     

肝素钠和小剂量高渗盐水对心肺复苏后兔小肠微循环灌注障碍的影响

目的:研究心肺复苏期间肝素钠和小剂量高渗盐水治疗对自主循环恢复后兔小肠微循环灌注的影响.方法:23只家兔开胸交流电致心室颤动,心室颤动5 min后行胸内心肺复苏,心肺复苏过程中随机滴注生理盐水(NS组)2mL/(kg·10 min)或生理盐水2 mL/(kg·10 min)加普通肝素钠60u/kg(H组)或7.5%NaCL 2 mL/(kg·10 min)+普通肝素钠60 u/kg(HSH组),另有3只家免作为假手术组,只进行外科手术操作,不给予致颤和心肺复苏.自主循环恢复后30min注入10%异硫氰酸荧光素钠-白蛋白0.3 mL/kg标记全身血液,循环2 min后处死动物取回肠末段,观察微循环灌注情况.结果:NS组中8只动物,6只完成实验;H组和HSH组各6只,各有5只完成实验.各组动物的生理学参数差异无统计学意义(P>0.05).兔经历5 min心跳骤停和心肺复苏后,在自主循环恢复后仍有严重的微循环灌注障碍,NS组的小肠微循环灌注面积为(22.78±4.21)%;H组为(29.73±1.21)%,和NS组相比二者差异有统计学意义(P<0.01);HSH组为(68.36±7.43)%,和其他2组相比差异均有统计学意义(P<0.05);而3只假手术组的动物显示了均匀一致的微循环灌注.结论:心肺复苏期间给予肝素钠和小剂量高渗盐水治疗可以改善复苏后兔小肠微循环灌注障碍.     

硫化氢对兔心搏骤停复苏后神经功能的影响

目的 观察硫化氢(H2S)对兔心肺复苏后早期NSE、S100B以及海马神经元凋亡的影响.方法 25只日本大耳白兔随机(随机数字法)分为3组:假手术组(S组)、心搏骤停组(CA组)和H2S处理组(H2S组).兔吸入5％氟烷麻醉后,气管切开,右股静脉置管用于给药,右颈动脉穿刺置管用于血压监测和采血.CA组和H2S组夹闭家兔气管导管8 min制备心搏骤停模型,并分别在恢复自主循环后吸入30％ O2或体积分数为80 x 10-6 H2S.于夹闭气管导管前(基础值)及恢复自主循环后30 min、60 min采动脉血检测血浆中神经元特异性烯醇化酶(neuronspecific enolase,NSE)和S100B的质量浓度.恢复自主循环后60 min处死家兔,取脑后分离海马固定于4％多聚甲醛中,待做组织病理学检查.计量资料以均数±标准差((x)±s)表示,采用单因素方差分析,组间比较采用SNK-q检验,以P＜0.05为差异有统计学意义.结果 与S组同时点比较,CA组和H2S组NSE和S100B的质量浓度均明显增高(P＜0.05),海马CA1区存活神经元减少,活化型caspase-3阳性神经元增多(P＜0.05);与CA组比较,H2S组恢复自主循环后60 min时S100B质量浓度显著降低(P＜0.05),海马CA1区存活神经元增多,活化型caspase-3阳性神经元显著减少(P＜0.05).结论 H2S抑制海马CA1区神经元凋亡,增加存活神经元数目,降低血浆中S100B的水平,进而减轻心搏骤停复苏后神经功能的损伤.     

亚低温对心肺复苏后患者神经功能预后的影响

目的:探讨亚低温技术在心肺复苏后对患者神经功能预后的影响。方法:回顾性分析我院2001-03-2008-05急诊抢救室收治的30例心肺复苏患者的临床资料,根据是否采用亚低温技术,患者随机分为两组:常温组与亚低温组,每组各15例。对复苏后患者的平均脑部温度、血氧饱和度(SaO2)、血酸碱值(pH)、平均动脉压(MAP)、意识障碍评分(GCS)等指标进行分析,3个月后对两组病人神经功能预后进行评定。结果:常温组与亚低温组患者复苏时平均脑部温度分为(36.7±1.3)℃和(33.5±1.1)℃(P<0.05),血氧饱和度(SaO2)、血酸碱值(pH)、平均动脉压(MAP)、意识障碍评分(GCS)等基本相近(P>0.05);3个月后两组神经功能转归良好率分别为40%和73%(P<0.05),其中亚低温6h内实施者优于6h后实施者;神经功能缺损评分(nerve functional in-sufficent,NFI)分别18.7±4.3和14.9±3.7(P<0.05),修改后的Barthel指数(modified Barthel index,MBI)分别为69.5±3.6和74.4±4.5(P<0.05)。结论:亚低温技术在心肺复苏后患者的脑复苏中具有显著的神经功能保护作用,可改善心肺复苏后患者的神经功能状况,实施降温越早,对脑复苏越有利。     

乌司他丁对心肺复苏后兔脑损伤和心功能的影响

目的 观察乌司他丁( ulinastatin,UTI)能否抑制自主循环恢复(restoration of spontaneous circulation,ROSC)后新西兰兔血浆致炎因子TNF-α、IL-6水平的升高,改善心功能、保护海马CA1区神经元细胞.方法 建立新西兰兔心搏骤停模型,ROSC后随机(随机数字法)分为对照组和UTI治疗组.观察ROSC后血浆TNF-α和IL-6水平的变化,监测心肌收缩和舒张功能;观察海马CA1区神经元细胞损伤和各主要脏器炎症细胞浸润的情况.依据正态检验结果用t检验或秩和检验( Mann-Whitney rank),多重比较用POST HOC检验,炎症因子和心功能的相关分析采用Pearson相关分析.结果 UTI显著抑制ROSC后TNF-α和IL-6水平的升高,UTI组ROSC后各时间点TNF-α和IL-6水平均低于对照组.UTI组动物ROSC后4、8、12 h的左心室射血分数(EF)、二尖瓣E/A峰比值高于对照组,左心室缩短分数(FS)值在ROSC后4、8h高于对照组,差异具有统计学意义(P＜0.05).Pearson相关分析表明ROSC后TNF-α和IL-6水平与EF明显相关.CA1区有活力的神经元细胞数对照组为(13.22 ±0.97),UTI组为(16.89±1.45),差异具有统计学意义(P=0.003);对照组的凋亡神经元细胞数为(15.67±1.37),UTI组为(13.67±1.03),差异具有统计学意义(P =0.019).UTI可以减轻ROSC后肠道、肝脏和肾脏内炎症细胞的浸润.结论 UTI通过减轻ROSC后兔肠道、肝脏和肾脏内炎症细胞的浸润,使血浆致炎因子TNF-α和IL-6水平降低,从而改善心功能和保护海马CA1区神经元细胞.     

腹腔降温对心肺复苏后兔海马神经损伤的影响

目的 探讨心肺复苏(CPR)后腹腔降温法是否较其他降温法对新西兰兔海马CA1区神经元细胞损伤更具有保护作用.方法 48只新西兰成年大白兔,采用交流电致颤的方式建立CPR模型,依据降温方式的不同,随机(随机数字法)分为常温组(NT),腹腔内降温组(PC),体表降温组(SC)和头部局部降温组(LC)各12只.观察不同降温方法对自主循环恢复后( ROSC)鼓膜温度和血浆主要电解质的影响,ROSC后72 h取脑组织,计算海马CA1区有活力的神经元细胞数和凋亡神经元细胞数.各组数据依据正态检验结果用单因素方差分析( one-way ANOVA)或秩和检验(Mann-Whitney rank),多重比较用LSD-t检验,ROSC率的比较用用行×列连表x2检验,以P＜0.05为差异具有统计学意义.结果 ROSC后PC法能快速诱导亚低温,PC组达到目标温度的时间为(26±7)min,而SC组和LC组达到目标温度的时间分别为(60 ±9)min,(69±12) min;维持亚低温阶段,除NT组外,其余各组鼓膜温度均稳定的维持在33～35 ℃之间.ROSC后各组动物在各观察时间点上组间主要电解质、酸碱、水平衡和肾功能指标之间差异无统计学意义.ROSC后72 h海马CA1区有活力的神经元细胞数分别为NT组(37.07 ±6.43)个/40×、LC组(35.13 ±6.97)个/40×、PC组(55.76±10.13)个/40×和SC组(50.70 ±7.38)个/40× (PC vs.NT,P＜0.01,SC vs.NT,P＜0.01,PC vs.SC,P=0.043,PC vs.LC,P＜0.01,LC vs.NT,P=0.520).凋亡神经元细胞数分别为NT组(44.07 ±6.09)个/40×、PC组(29.88±4.81)个/40×、SC组(33.55 ±5.67)个/40×和LC组(42.27 ±5.20)个/40×(PC vs.NT,P＜0.01; SC vs.NT,P＜0.01; PC vs.LC,P＜0.01; SC vs.LC,P＜0.01,PC vs.SC,P=0.026),LCvs.NT,P=0.364).结论 ROSC后新型腹腔降温法能快速诱导亚低温和维持亚低温,对神经元的保护作用优于体表降温和头部局部降温法.     

乌司他丁对心肺复苏后兔心脏保护作用的实验研究

目的了解心肺复苏后心功能不全的发生情况,探讨乌司他丁心脏保护作用的机制。方法建立心肺复苏家兔模型,30只新西兰大白兔随机分为手术对照组(S组)、常规复苏组(C组)和乌司他丁组(U组),每组10只,S组只行手术操作,不致颤;C组造成心搏骤停并行常规复苏;U组在心搏骤停并复苏成功后静脉注射乌司他丁(Ulilastatin,UTI)2.5万U/kg。动态观察左室舒张末压(LVEDP)、左室内压上升和下降速率(±dp/dt)、血清心肌酶(CK、CK-MB)的变化,取左心室肌行光、电镜检查。结果与S组比较,C组和U组复苏成功后LVEDP和CK、CK-MB有不同程度升高(P<0.01),±dp/dt不同程度下降(P<0.01),光、电镜下可见不同程度的心肌损害。U组与同时相C组比较,LVEDP和CK、CK-MB升高幅度减小(P<0.05,P<0.01),±dp/dt下降程度减轻(P<0.05),光、电镜下心肌损害减轻。结论乌司他丁可以改善心肺复苏后心功能不全,减轻心肌损伤,对复苏后心脏有保护作用。     

Molecular mechanisms of therapeutic hypothermia on neurological function in a swine model of cardiopulmonary resuscitation

Objective

To explore the molecular mechanisms by which mild hypothermia following resuscitation improves neurological function in a porcine model of cardiac arrest.

Methods

Thirty-three inbred Chinese Wuzhishan (WZS) minipigs were used. After 8 min of untreated ventricular fibrillation (VF), the surviving animals (n = 29) were randomly divided into two groups including serum group (n = 16) and molecular group (n = 13). Serum group animals were used to measure porcine-specific tumour necrosis factor-alpha (TNF-α), interleukin (IL-6, IL-10), matrix metalloproteinase (MMP9), Aquaporin-4 (AQP4), tissue inhibitor to metalloproteinase-1 (TIMP1), neuron-specific enolase (NSE) and S100B at 0.5 h, 6 h, 12 h, 24 h and 72 h recovery by enzyme-linked immunosorbent assay (ELISA). Molecular group animals were used to measure cerebral cortex messenger RNA (mRNA) and protein expression of nuclear factor-κB (NF-κB), MMP9 and AQP4 by real-time (RT) quantitative polymerase chain reaction (PCR) and Western blotting at 24 h and 72 h recovery. Animals were further divided into either normothermia or hypothermia groups. Hypothermia (33 °C) was maintained for 12 h using an endovascular cooling device. Swine neurologic deficit scores (NDS) were used to evaluate neurological function at 24-h and 72-h recovery.

Results

Twenty-nine of the 33 (87.9%) animals were successfully resuscitated. The hypothermia group exhibited higher survival rates at 24 h (75%) and 72 h (62.5%) compared to the normothermia group (37.5% and 25%, respectively). Hypothermia markedly inhibited expression of NF-κB, TNF-α, MMP9 and NSE, and promoted expression of TIMP1 (P < 0.01). The mean NDS at 24-h and 72-h recovery was 112.5 and 61, respectively, in the hypothermic group, and 230 and 207.5, respectively, in the normothermia group.

Conclusion

Brain protection induced by hypothermia involves inhibition of inflammatory and brain edema pathways.     

亚低温对心脏骤停后大鼠心肌保护的代谢组学研究

目的基于超高效液相色谱-飞行时间质谱(UPLC-QTOF-MS)技术寻找CA后大鼠心肌损伤的潜在生物标志物,初步揭示亚低温对心肌保护作用的机制。方法建立窒息性CA模型,将20只自主循环恢复后的SD大鼠随机分为常温组、亚低温组,ROSC后24h收集心肌组织样本进行代谢组学检测,采用SIMCA-P 14.1和MetaboAnalyst 4.0对预处理后的数据进行代谢轮廓分析,筛选差异代谢物,将内源性代谢物进行代谢通路分析。结果成功制作了大鼠窒息性CA模型,心肌HE染色显示,常温组大鼠心肌结构紊乱,心肌纤维断裂,间质充血,细胞核染色不均匀,亚低温治疗后改善了心肌损伤程度;代谢组学检测结果显示,常温组和亚低温组心肌代谢指纹不同,共筛选出20种差异代谢物,代谢通路分析提示嘌呤代谢、缬氨酸/亮氨酸/异亮氨酸代谢在亚低温干预后显著改变。结论亚低温治疗在一定程度上减轻CA后心肌损伤程度,嘌呤代谢和氨基酸代谢参与了亚低温对心肌的保护。     

Effects of hypothermia on the liver in a swine model of cardiopulmonary resuscitation

BACKGROUND:

The study aimed to explore the effects of hypothermia state induced by 4 ºC 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 ºC 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 Ca²⁺-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; Ca²⁺-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 ºC 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.KEY WORDS: Therapeutic hypothermia, Cardiac arrest, Liver, Hemodynamics     

山莨菪碱对心脏停搏大鼠复苏中微循环的影响

目的 观察复苏早期给予山莨菪碱(Ani)对心脏停搏(CA)大鼠肠系膜微循环和肠壁组织血流量变化的影响.方法 采用电击法制备大鼠CA模型,将实验动物随机分为4组,每组15只.待大鼠CA后4 min行呼吸机辅助呼吸、胸外按压.静脉补液复苏.对照组仅给予生理盐水;肾上腺素组(Epi组)注射Epi200 μg/kg;Epi+低剂量Ani组(低剂量Ani组)注射Epi 200 μg/kg+Ani 5 mg/kg;Epi+高剂量Ani组(高剂量Ani组)注射Epi 200 μg/kg+Ani 10 mg/kg.观察大鼠肠系膜微动、静脉血管再通率和再通血管管径及肠壁血流量.结果 微动、静脉再通率:高剂量Ani组(66.6%,60.0%)>低剂量Ani组(60.0%,53.3%)>对照组(40.0%,40.0%)>Epi组(26.7%,20.0%),Epi组与两个Ani组间差异均有统计学意义(P均<0.05).微动、静脉血管管径:自主循环恢复(ROSC)30 rain和60 min时高剂量Ani组>低剂量Ani组>对照组>Epi组.其中30 min时高、低剂量Ani组与Epi组比较差异有统计学意义(P均<0.05);60 min时低剂量Ani组微静脉血管管径与Epi组比较差异无统计学意义;高、低剂量Ani组间比较差异均无统计学意义.高、低剂量Ani组大鼠ROSC 15 min肠壁组织血液灌注量明显高于对照组和Epi组.随时问延长明显增高.持续至ROSC 60 min.结论 复苏早期给予Ani干预可改善组织微循环状态,从而提高ROSC率和复苏成功率.     

温州地区开展亚低温治疗对心肺复苏后昏迷患者预后影响的研究

目的探讨温州地区推广亚低温治疗（HT）对心肺复苏（CPR）后昏迷患者预后的影响。 方法温州地区成立1家推广示范基地及10家推广基地,自2014年1月至2016年12月,对CPR后昏迷患者实施HT。记录所有患者亚低温治疗相关信息,比较推广期间3年患者ICU出院存活率、神经功能恢复良好率及严重致残率。 结果推广期间共对133例CPR后昏迷患者实施HT,推广第1年、第2年、第3年分别为28、46、59例。推广第1年、第2年、第3年达到目标体温时间[8.0（3.0,18.8）、10.0（4.8,20.0）、6.0（2.0,12.0）h]、药物使用率[17（60.7%）、43（93.5%）、42（71.2%）]及肌松剂使用率[0（0%）、1（2.2%）、13（22.0%）]比较,差异均有统计学意义（H = 10.475,P = 0.005;χ² = 12.250,P = 0.002;χ² = 17.647,P < 0.001）。推广期间ICU出院存活率呈现逐年上升趋势,严重致残率呈现逐年下降趋势;但3年间比较差异均无统计学意义（χ² = 2.537,P = 0.281;χ² = 0.308,P = 0.857）。推广3年间神经功能恢复良好率比较,差异有统计学意义（χ² = 12.232,P =0.002）,且推广第3年较第1年及第2年神经功能恢复良好率更高[16（27.1%）、1（3.6%）、3（6.5%）,P均< 0.017]。 结论规范化的HT能有效地促进神经功能恢复。     

Postresuscitation care with mild therapeutic hypothermia and coronary intervention after out-of-hospital cardiopulmonary resuscitation: a prospective registry analysis

Introduction

Mild therapeutic hypothermia (MTH) has been shown to result in better neurological outcome after cardiopulmonary resuscitation. Percutaneous coronary intervention (PCI) may also be beneficial in patients after out-of-hospital cardiac arrest (OHCA).

Methods

A selected cohort study of 2,973 prospectively documented adult OHCA patients within the German Resuscitation Registry between 2004 and 2010. Data were analyzed by backwards stepwise binary logistic regression to identify the impact of MTH and PCI on both 24-hour survival and neurological outcome that was based on cerebral performance category (CPC) at hospital discharge. Odds ratios (95% confidence intervals) were calculated adjusted for the following confounding factors: age, location of cardiac arrest, presumed etiology, bystander cardiopulmonary resuscitation, witnessing, first electrocardiogram rhythm, and thrombolysis.

Results

The Preclinical care dataset included 2,973 OHCA patients with 44% initial return of spontaneous circulation (n = 1,302) and 35% hospital admissions (n = 1,040). Seven hundred and eleven out of these 1,040 OHCA patients (68%) were also registered within the Postresuscitation care dataset. Checking for completeness of datasets required the exclusion of 127 Postresuscitation care cases, leaving 584 patients with complete data for final analysis. In patients without PCI (n = 430), MTH was associated with increased 24-hour survival (8.24 (4.24 to 16.0), P < 0.001) and the proportion of patients with CPC 1 or CPC 2 at hospital discharge (2.13 (1.17 to 3.90), P < 0.05) as an independent factor. In normothermic patients (n = 405), PCI was independently associated with increased 24-hour survival (4.46 (2.26 to 8.81), P < 0.001) and CPC 1 or CPC 2 (10.81 (5.86 to 19.93), P < 0.001). Additional analysis of all patients (n = 584) revealed that 24-hour survival was increased by MTH (7.50 (4.12 to 13.65), P < 0.001) and PCI (3.88 (2.11 to 7.13), P < 0.001), while the proportion of patients with CPC 1 or CPC 2 was significantly increased by PCI (5.66 (3.54 to 9.03), P < 0.001) but not by MTH (1.27 (0.79 to 2.03), P = 0.33), although an unadjusted Fisher exact test suggested a significant effect of MTH (unadjusted odds ratio 1.83 (1.23 to 2.74), P < 0.05).

Conclusions

PCI may be an independent predictor for good neurological outcome (CPC 1 or CPC 2) at hospital discharge. MTH was associated with better neurological outcome, although subsequent logistic regression analysis did not show statistical significance for MTH as an independent predictor for good neurological outcome. Thus, postresuscitation care on the basis of standardized protocols including coronary intervention and hypothermia may be beneficial after successful resuscitation. One of the main limitations may be a selection bias for patients subjected to PCI and MTH.     

亚低温对心肺复苏后患者神经功能状况及生活质量的影响

目的　探讨亚低温对心肺复苏后患者神经功能状况及生活质量的影响及其机制。方法　采用格拉斯哥昏迷评分 (GCS)、神经功能缺损评分 (NFI)、Barthel指数 (MBI)及生活质量评分 (QOL)对心肺复苏后患者的神经功能状况及生活质量进行评定 ,并观察亚低温对他们的影响。结果　在心肺复苏后第7d ,亚低温组GCS评分明显比常规治疗组高 (P <0 0 5 ) ;在复苏后第 12周和 2 4周 ,亚低温组NFI评分及QOL评分均明显较常规治疗组低 (P <0 0 5 ) ,MBI评分明显较常规治疗组高 (P <0 0 1)。结论　亚低温可改善心肺复苏后患者的神经功能状况 ,提高患者的生活质量     

心肺复苏中宏循环与微循环的制衡

"大河之水"与"涓溪之源"在人们的意识中是无法分离的."涓涓细流终汇入江河,大河若是无水小河干",也是人们的口头禅.当发生心搏骤停时,主动脉血流停滞,无动脉搏动,微循环发生障碍,组织无供血、供氧,相继会发生组织细胞缺血、缺氧,出现组织损伤、坏死的病理变化.