插入式腹主动脉按压对心搏骤停兔心肺脑复苏的实验研究

目的：探讨插入式腹主动脉按压心肺复苏（IAAC-CPR）对心搏骤停兔心肺脑复苏的效果。方法健康新西兰大白兔10只,雌雄不拘,按随机数字表法分为传统胸外按压心肺复苏（CC-CPR）组和IAAC-CPR组,每组5只。经颈静脉快速推注冰氯化钾并夹闭气管导管制备心搏骤停模型;心搏骤停3 min后开始实施心肺复苏（CPR）,CC-CPR组为呼吸机辅助通气+胸外按压;IAAC-CPR组为呼吸机辅助通气+胸外按压+腹主动脉按压。观察CPR过程中血流动力学和脑皮质血流的变化;记录自主循环恢复（ROSC）时间,观察动物24 h生存情况、24 h神经功能评分及腹部器官情况等。结果 IAAC-CPR组复苏后30、60、90、120 s时脑血流量（CBF,PU值）及平均动脉压（MAP,mmHg,1 mmHg＝0.133 kPa）均明显高于CC-CPR组（CBF 30 s：16.1±6.0比7.8±2.2,60 s：91.6±11.8比57.3±23.2,90 s：259.9±74.9比163.6±50.3,120 s：301.5±60.5比208.4±23.8;MAP 30 s：46.4±9.4比31.4±8.7,60 s：55.8±13.8比34.0±11.5,90 s：61.2±11.5比38.2±10.1,120 s：63.6±11.8比40.2±10.2;均P＜0.05）。与CC-CPR组比较,IAAC-CPR组ROSC所需时间明显缩短（s：182.0±59.0比312.6±86.6,t＝2.787,P＝0.024）,24 h神经功能评分明显下降（分：2.4±1.7比4.6±0.6,t＝2.974,P＝0.023）;而复苏成功率（80.0%比60.0%,χ2＝0.000,P＝1.000）、24 h存活率升高（80.0%比40.0%,χ2＝0.417,P＝0.519）,但差异无统计学意义。ROSC后24 h尸解动物均未发现肝脏损伤。结论在心搏骤停兔复苏早期,IAAC-CPR较CC-CPR取得了更好的脑血流灌注,明显减轻了心搏骤停兔的神经系统功能损伤,且无腹部器官损伤。     

Two-stage resuscitation of the cat brain after prolonged cardiac arrest

Following prolonged cardiac arrest, reperfusion of the brain is endangered by the low blood perfusion pressure during the early resuscitation phase. In order to avoid low perfusion brain injury, a two-stage resuscitation protocol was applied to cats submitted to 30 min potassium chloride induced cardiac arrest: first, the heart was resuscitated, followed — after stabilisation of blood pressure — by recirculation of the brain. During cardiac resuscitation the brain was disconnected from the general circulation by inflating a pneumatic cuff around the neck. The results were compared with the outcome of conventional one-stage resuscitation following 15 min cardiac arrest. Cardiac resuscitation was successful in 5 out of 8 animals with 15 min and in 6 out of 13 animals with 30 min cardiac arrest. In successfully resuscitated animals of both groups, brain energy metabolism recovered to normal within 3 h although two-stage resuscitation increased brain ischemia time to 37–61 min. Twostage resuscitation, in consequence, is a promising approach for revival of the brain after prolonged cardiac arrest.     

脑梗塞患者缺血半暗带的PET检查

对正电子发射计算机断层显像 (Positronemissiontomography ,PET)在缺血性脑血管病早期缺血半暗带判定中的作用进行了综述。PET不但能早期发现半暗带的部位及大小 ,而且可以判定其中存活组织的生存状态 ,并能预测其转归 ,为缺血性脑血管病早期治疗对象的筛选及缺血半暗带的研究提供了一种新的、有效的检查手段。     

低温关胸心肺转流行心肺复苏的实验研究

目的　观察狗心脏停搏15min后深低温(26℃～27℃)和浅低温(33℃～34℃)关胸心肺转流(CPB)对心肺复苏(CPR)的影响。方法　10只麻醉狗,分2组,每组各5只。第1组为浅低温组,第2组为深低温组,用10%氯化钾静注后,使心脏停搏15min,然后用动静脉插管方法立即行关胸心肺转流。第1组食道温度降至33℃～34℃,第2组降至26℃～27℃,15min后逐渐升温至正常范围(36℃～37℃)。复苏期间监测心电图、平均动脉压、中心静脉压和瞳孔直径,3h后观察颅内压和最终效果。结果　第1组全部恢复自主循环(100%),第2组仅3只(60%)恢复自主循环;第1组的自主循环恢复时间为(444±192.2)sec,明显短于第2组(1980±681.5)sec(P＜0.05),其复苏后3h颅内压为(2.4±0.44)cmH     

一日法PET脑血流-脑代谢联合显像评价不同程度脑血管狭窄患者的脑血流及代谢特点

目的采用一日法PET脑血流-脑代谢联合显像评价不同程度脑血管狭窄患者的脑血流及代谢特点。方法回顾性分析2012年1月至2015年2月首都医科大学宣武医院神经科门诊89例缺血性脑血管病(ICVD)患者[重度脑血管狭窄组(A组,n=41),轻中度脑血管狭窄组(B组,n=48)]的PET脑血流灌注显像和葡萄糖代谢显像资料。采用一日法,先后进行13N-氨水(13N-NH3)和18氟-氟代脱氧葡萄糖(18F-FDG)脑PET显像,获得脑血流灌注和脑葡萄糖代谢影像,以及脑血流值、脑代谢值、脑血流减低率、脑代谢减低率和脑代谢/脑血流比值。结果A组患者的13N-NH3和18F-FDG显像阳性率分别为74.2%(98/132)和92.4%(122/132);B组分别为60.6%(43/71)和85.9%(61/71),其中5例显像正常。A组以单侧多灶和双侧多灶多见,且呈不对称性分布;B组以单侧单灶和单侧多灶多见。A组匹配型病灶68个,B组30个;A组不匹配型病灶64个,B组41个。A组匹配型病灶中,轻度、中度、重度受损病灶数目分别为29个、15个、24个;B组匹配型病灶中,其中轻度、中度受损病灶数目分别为26个、4个,无重度受损病灶。A、B组匹配型病灶之间的脑血流值(0.754±0.182,0.849±0.052)、脑代谢值(0.823±0.191,1.028±0.102)、脑血流减低率(0.252±0.194,0.154±0.115)和脑代谢减低率(0.294±0.183,0.188±0.123)比较,差异均具有统计学意义(P<0.05)。结论ICVD患者脑血管狭窄程度不能代表脑功能受损程度。一日法PET脑血流-脑代谢联合显像是评价ICVD脑功能受损程度的良好方法。     

插入式腹主动脉按压心搏骤停兔复苏效果

目的 通过比较插入式腹主动脉按压心肺复苏(IAAC-CPR)与传统胸外按压心肺复苏(CC-CPR)对心搏骤停(CA)兔复苏过程中血流动力学及神经系统改变情况,初步评价IAAC-CPR的心肺脑复苏效果及其影响脑灌注和复苏预后的机制.方法 健康新西兰大白兔28只,体质量在2.0～2.5 kg,雌雄不拘,按随机数字表法,分为CC-CPR组(实施传统胸外按压)和IAAC-CPR组(于胸外按压放松期,施行腹主动脉按压),每组14只.冰氯化钾联合气管夹闭建立CA模型,由建模前5 min开始持续监测动物心电图(ECG)、主动脉收缩压(SBP)、舒张压(DBP)、平均动脉压(MAP)、心率(HR)及脑皮质血流(CBF)情况直至实验结束;分别记录复苏前基础值(1次/min),复苏30 s、60 s、90 s及120 s的MAP与SBP及脑皮质血流;并于建模前基础时点、自主循环恢复(ROSC)后2h、6h留取血液标本.比较两组动物的平均动脉压(MAP)、收缩压(SBP)、脑皮质血流(CBF)、血清S100B蛋白含量、ROSC率、复苏成功率、24 h存活率及24 h神经功能评分的差异.比较两组间差异时,均数比较采用独立样本t检验,率的比较用x2检验确切概率法.结果 复苏30 s、60 s、90 s、120 s内,IAAC-CPR组MAP、SBP及CBF均高于CC-CPR组,其中MAP值(mm Hg,1 mm Hg =0.133 kPa)为[30 s:(46.4±9.4) vs.(31.4±8.7,60)s:(55.8±13.8)vs.(34.0±11.5); 90s:(61.2±11.5)vs.(38.2±10.1); 120 s:(63.6±11.8) vs.(40.2±10.2);95％ CI,30s:-21.73～-12.41,60 s:-28.03～-16.26,90s:-25.27～-14.87,120 s:-25.38～-13.19;t值2:30 s:-7.536,60 s:-7.734,90 s:-7.943,120s:-6.505; P＜0.05,P＜0.01];SBP值(mm Hg)为[30s:(62.6±9.2)vs.(43.4±15.1); 60s:(75.4±14.0)vs.(50.4±13.8); 90s:(78.4±12.6)vs.(59.4±16.2),120s:(82.8±10.3)vs.(64.3±15.9);95％ CI,30 s:-28.91～-9.51,60 s:-35.82～-14.18,90s:-30.28～-7.71,120s:-28.93～-8.07;t值2:30s:-4.071,60s:-4.751,90s:-3.460,120s:-3.647;P值,30s:P＜0.05,P＜0.01,60s:P＜0.05,P＜0.01,90s:P=0.02,P＜0.05,120s:P=0.01,P＜0.05]; CBF值为[30 s:(16.1±6.0)vs.(7.8±2.2); 60s:(91.6±11.8)vs.(57.3±23.2); 90s:(259.9±74.9) vs.(163.6±50.3); 120s:(301.5±60.5)vs.(208.4 ±23.8);95％ CI,30 s:-14.82～-1.70,60 s:-61.24～-7.49,90s:-189.45～-3.29,120s:-160.12 ～-26.03;t值2:30 s:-2.904,60 s:-2.948,90s:-2.387,120s:-3.201;P值,30 s:P=0.020,P＜0.05,60 s:P=0.018,P＜0.05,90 s:P =0.044,P＜0.05,120s:P=0.013,P＜0.05].两组基础点血清S100B蛋白水平差异无统计学意义(P =0.781,P＞0.05),ROSC后2h、6 h IAAC-CPR组血清S100B蛋白水平(pg/mL)低于CC-CPR组,分别为:[2h:(148.7±19.9)vs.(176.0±17.5);6 h:(237.7±17.7)vs.(267.0±14.8); 95％CI,2 h:4.53 ～50.05,6 h:9.29 ～49.26;t值,2 h:2.519,6 h:3.164;P值,2h:P =0.022,P＜0.05,6 h:P=0.007,P＜0.05).ROSC率及24 h生存率差异无统计学意义,复苏成功率及24 h神经功能评分IAAC-CPR组优于CC-CPR组(复苏成功率:80％vs.60％,x2值:5.250:P=0.022,P＜0.05; 24 h神经功能评分:(3.3±1.49)vs.(4.4±0.94);t值,t=2.429; 95％CI,0.18 ～2.11;P值:P=0.024,P＜0.05).所有动物实验后尸检未见腹腔内器官损伤.结论 在心搏骤停兔的复苏过程中,IAAC-CPR可产生较高的平均动脉压(MAP)、收缩压(SBP)及脑皮质血流(CBF),从而减轻了CA所致循环中断造成的脑组织等重要脏器损伤,提高复苏成功率及24 h动物神经功能评分,其心肺脑复苏效果优于CC-CPR.     

Tilting for perfusion: Head-up position during cardiopulmonary resuscitation improves brain flow in a porcine model of cardiac arrest

IntroductionCerebral perfusion is compromised during cardiopulmonary resuscitation (CPR). We hypothesized that beneficial effects of gravity on the venous circulation during CPR performed in the head-up tilt (HUT) position would improve cerebral perfusion compared with supine or head-down tilt (HDT).MethodsTwenty-two pigs were sedated, intubated, anesthetized, paralyzed and placed on a tilt table. After 6 min of untreated ventricular fibrillation (VF) CPR was performed on 14 pigs for 3 min with an automated CPR device called LUCAS (L) plus an impedance threshold device (ITD), followed by 5 min of L-CPR + ITD at 0° supine, 5 min at 30° HUT, and then 5 min at 30° HDT. Microspheres were used to measure organ blood flow in 8 pigs. L-CPR + ITD was performed on 8 additional pigs at 0°, 20°, 30°, 40°, and 50° HUT.ResultsCoronary perfusion pressure was 19 ± 2 mmHg at 0° vs. 30 ± 3 at 30° HUT (p < 0.001) and 10 ± 3 at 30° HDT (p < 0.001). Cerebral perfusion pressure was 19 ± 3 at 0° vs. 35 ± 3 at 30° HUT (p < 0.001) and 4 ± 4 at 30° HDT (p < 0.001). Brain–blood flow was 0.19 ± 0.04 ml min⁻¹ g⁻¹ at 0° vs. 0.27 ± 0.04 at 30° HUT (p = 0.01) and 0.14 ± 0.06 at 30° HDT (p = 0.16). Heart blood flow was not significantly different between interventions. With 0, 10, 20, 30, 40 and 50° HUT, ICP values were 21 ± 2, 16 ± 2, 10 ± 2, 5 ± 2, 0 ± 2, −5 ± 2 respectively, (p < 0.001), CerPP increased linearly (p = 0.001), and CPP remained constant.ConclusionDuring CPR, HDT decreased brain flow whereas HUT significantly lowered ICP and improved cerebral perfusion. Further studies are warranted to explore this new resuscitation concept.     

P（cv-a）CO 2/C（a-v）O 2 ratio在感染性休克早期目标导向性复苏中的潜在价值

目的探讨中心静脉血二氧化碳分压-动脉血二氧化碳分压差/动脉血氧含量-静脉血氧含量差［P（cv-a）CO₂/C（a-v）O₂ ratio］在感染性休克早期目标导向性复苏中的应用。 方法收集自2018年6月至2019年6月在新疆维吾尔自治区人民医院ICU接受治疗的感染性休克患者44例。根据P（cv-a）CO₂/C（a-v）O₂ ratio值将患者分为A、B 2组,其中A组为P（cv-a）CO₂/C（a-v）O₂ ratio＜1.6,B组为P（cv-a）CO₂/C（a-v）O₂ ratio≥1.6。比较2组患者的基线资料［性别、年龄、感染部位、急性生理学与慢性健康状况（APACHE Ⅱ）评分与序贯器官衰竭评估（SOFA）评分］、基本参数［中心静脉压（CVP）、平均动脉压（MAP）、小时尿量、血管活性药物使用量、24 h出入量、血红蛋白、乳酸水平］、氧代谢参数［0、6、12、24 h的动脉血氧分压（PaO₂）,动脉血氧饱和度（SaO₂）,中心静脉血氧分压（PcvO₂）,中心静脉血氧饱和度（ScvO₂）,P（cv-a）CO₂（gap）,P（cv-a）CO₂/C（a-v）O₂ ratio,氧合指数,氧摄取率,及6、12 h的乳酸清除率］及转归［血管活性药物使用时间,机械通气时间,24、48、72、96 h的APACHEⅡ评分和SOFA评分,住ICU时间,住院时间,28 d病死率］等数据。 结果2组患者基线资料比较差异无统计学意义（P＞0.05）。0 h 2组间P（cv-a）CO₂/C（a-v）O₂ ratio、氧分压、氧合指数、氧摄取率、乳酸、P（cv-a）CO₂（gap）比较,差异均有统计学意义（P＜0.05）;6 h 2组间乳酸清除率比较,差异有统计学意义（P＜0.05）。2组间1、3、5、7 d APACHE Ⅱ评分、SOFA评分、血管活性药物使用时间（去甲肾上腺素）、机械通气时间、住ICU时间、住院时间及28 d病死率比较,差异均无统计学意义（P＞0.05）。 结论P（cv-a）CO₂/C（a-v）O₂ ratio在感染性休克早期目标导向性复苏中可作为补充指标,评价组织乏氧代谢,指导治疗。     

失血性休克及复苏后腓肠肌与肠组织损伤敏感性差异的研究

目的 :探讨腓肠肌和肠组织对缺血、缺氧损伤敏感性的差异。方法 :采用 Wistar大鼠失血性休克及复苏模型 ,随机分为 6组 :假手术对照组 ,休克 90分钟组 ,休克 90分钟复苏 0 .5、1、2和 6小时组 ;进行腓肠肌和肠组织血流量和氧代谢的检测。结果 :失血性休克 90分钟 ,腓肠肌组织血流量降低程度重于肠组织 ,且复苏后血流量回升的速度慢于空肠、回肠和结肠 ;复苏后 2小时各组织氧耗和氧摄取率明显降低 ,肠组织降低程度重于腓肠肌。结论 :失血性休克及复苏后肠组织血流量降低程度虽轻于腓肠肌 ,但对氧的摄取和利用能力低于腓肠肌 ,这与肠组织对缺血、缺氧损伤敏感性较高有关     

不同降温方法对大鼠心肺脑复苏的作用

目的研究亚低温脑复苏时不同降温方法的效果及对大鼠脑的保护作用。方法建立心肺复苏模型，SD大鼠45只，分成对照组、常温复苏组及低温复苏A组（体表降温）、低温复苏B组（0．5ml·kg^-1·min^-1静注4℃ NS）、低温复苏C组（0．5ml·kg^-1·min^-1静注4℃NS结合体表降温）、低温复苏D组（1ml·kg^-1·min^-1静注4℃NS）和低温复苏E组（1ml·kg-^1·min^-1静注4℃NS结合体表降温），分别观察各组血清及大脑皮质SOD、MDA、NO、Na^＋ K^＋ -ATP酶及P53、Bax、Bcl-2表达和脑组织含水量比。结果低温复苏各组均能达到亚低温状态，特别是低温复苏D、E组达到亚低温状态仅需（26．71±4．65）min及（10．00±2．52）min。低温复苏D组脑组织含水量比、MDA、NO、P53和Bax光密度值分别为（79．58±0．40）％、（14．16±2．36）nmol／gprot、（35．28±4．94）μmol／gprot、（0．0136±0．0001）和（0．0304±0．0019），低温复苏E组分别为（79．46±0．30）％、（10．30±3．16）nmol／gprot、（33．18±4．93）μmol／gpmt、（0．0134±0．0040）和（0．0323±0．0029）．均较常温复苏组明显下降（P〈0．05）。低温复苏D组脑组织SOD、Na^＋ K^＋ -ATP酶分别为（114．45±3．07）U／mgprot、（30．50±2．06）μmolpi／（mgpnt·hour），低温复苏E组分别为（114．45±8．11）U／mgprot、（28．10±5．67）μmolpi／（mgpnt·hour），均较常温复苏组明显升高（P〈0．05）。结论静脉快速灌注冷生理盐水或同时结合体表降温均能在较短的时间内达到理想的亚低温状态并产生良好的脑保护效果。     

窒息心脏骤停动物模型中碳酸氢钠对复苏的影响

目的 研究碳酸氢钠(sodium bicarbonate,SB)在窒息心脏骤停(asphyxiation cardiac arrest,ACA)动物模型中对复苏预后的影响.方法 32只五指山幼猪随机(随机数方法)平均分成SB组(n=16)和对照组(n=16),通过在呼吸末堵塞气管插管方法制作窒息型的心脏骤停模型,在成功制作心脏骤停模型后8 min后行标准心肺复苏.SB组在复苏即刻予以SB(1.0 mEq/kg稀释到40 mL)静脉推注,对照组予以40 mL生理盐水静脉推注.比较两组实验动物的自主循环恢复(return of spontaneous circulation,ROSC)率,复苏前和复苏后6h内血压,心排血量(cardiac output,CO)血液pH值,血清钠离子浓度变化.在基础状态以及复苏后6h利用正电子发射型计算机断层显像(positron emission tomography,PET)测定左心室心肌代谢最大标准化摄取值(themaximum standardized uptake value,SUVmax).结果 SB组复苏成功率(10/16)较对照组复苏成功率(8/16)高,6h生存时间均值SB组较对照组长(3.63±0.76) hvs.(2.45±0.70)h,但差异均无统计学意义;两组实验动物在复苏前后血清钠离子比较差异无统计学意义;复苏后6h两组左心室心肌代谢SUVmax比较:SB组较对照组要高(1.32±0.20)vs.(1.10±0.14),P=0.035.结论 窒息心脏骤停在复苏过程中使用SB可能会增加复苏成功率以及改善复苏后心肌代谢,且没有发生高钠血症.     

Maximum FIO<Subscript>2</Subscript> in minimum time depending on the kind of resuscitation bag and oxygen flow

Objective To analyze what FIO₂ can be reached, and how long it takes using the different autoinflated resuscitation bags and increasing oxygen flows.Design Experimental analysis on the effect of three different models of autoinflated resuscitation bag and increasing oxygen flows in the final FIO_2, and time spent to reach it.Setting Laboratory, with a gas analyzer and a lung simulator to measure inspired FIO₂.Interventions Simulated cardiopulmonary resuscitation. Three different autoinflated resuscitation bags were studied; A, the classic one with oxygen delivery directly into the bag, without reservoir, B, a new one without the reservoir device; and C, a new one with the reservoir device properly implemented. Increasing oxygen flows were administered until FIO₂ stabilized.Results With model A the maximum FIO₂ reached was 0.73 in 70 s using a 20 l/min oxygen flow. With model B the maximum FIO₂ reached was 0.65 in 90 s using a 20 l/min oxygen flow. The best FIO₂ (0.99) was reached using model C in 55 s with 12 l/min oxygen flow. In the three models a high correlation between oxygen flow and FIO₂ was found (r>0.8).Conclusions It is mandatory to use model C resuscitation autoinflated bag with 12 l/min of oxygen flow during the resuscitation maneuvers. Using another autoinflated bag model, maximum oxygen flows (i.e., 20 l/min) are needed. The resuscitation autoinflated bags showed less effectiveness when they were not properly assembled.     

犬心跳骤停复苏后脑和全身氧供需关系的观察

目的　观察和比较犬心跳骤停 (CA)复苏后脑和全身氧利用率 (O2 UC)的变化。方法　 5只犬采用经胸壁电击致室颤 /心跳骤停 (VF/CA) 8min ,开胸心肺复苏 (OCCPR)恢复自主循环 (RSC)后同时观察 4h内脑和全身O2 UC的变化。结果　 5只犬均CPR成功后维持稳定的血流动力学状态 ,仅RSC后 12 0min心输出量 (CO)较CA前明显降低 (2 1± 0 .8L/minvs 3 4± 1 4L/min ,P <0 0 5 )。RSC后 30min脑O2 UC即显著高于CA前 (0 5 7± 0 11vs 0 43± 0 0 8,P <0 0 5 ) ,RSC后 6 0、12 0和 2 40min时脑O2 UC则渐进性升高 ,且非常显著高于CA前 (0 6 5± 0 0 9、0 72± 0 0 9和 0 78± 0 0 6vs 0 43± 0 0 8,P均 <0 0 1) ;而直至RSC后 12 0min全身O2 UC才显著高于CA前 (0 36± 0 10vs 0 2 0± 0 0 5 ,P <0 0 5 )。结论　CA经OCCPR后脑和全身均发生氧供相对于氧需的不足 ,而且脑氧供需失衡的发生较全身更早、更严重 ,提示CPR后应力求尽早改善脑氧输送 ,同时脑氧代谢的监测可为脑复苏提供有力的指导     

猪室颤心脏骤停模型心肺复苏后急性肺损伤CT表现与病理对照

目的对照分析猪室颤(5~10 min)心脏骤停模型心肺复苏后急性肺损伤的CT征象及其病理学表现。方法选用健康雄性家猪16只,利用电刺激诱导室颤5~10 min后进行CPR,自主循环恢复后8~10 h行CT扫描,后立刻处死猪留取肺标本进行病理观察,分析其CT征象及病理学特征。结果 16头猪室颤心脏骤停模型均制作成功,CT扫描:16头猪(100%)均可见"磨玻璃征"及肺实变征象,"磨玻璃征"占全肺体积18.4%~42.3%(平均27.3%);肺实变病灶占全肺体积13.8%~40.5%(平均24%)。2头猪气胸(12.5%),5头猪肋骨骨折(31.3%),5头猪胸腔积液(31.3%)。病理镜下见病变区肺泡水肿、出血、肺泡塌陷、透明膜形成、肺毛细血管充血等。结论心跳骤停CPR后可造成不同程度的急性肺损伤,主要包括肺挫裂伤及肺缺血-再灌注损伤。CT检查可敏感反映上述病理表现,主要表现为不同程度的磨玻璃样病变及肺实变。     

Transtracheal O2 insufflation (TOI) as an alternative method of ventilation during cardiopulmonary resuscitation

We examined the efficiency of continuous transtracheal O₂ insufflation (TOI) as a method of ventilation during cardiopulmonary resuscitation (CPR) in a canine model. The tip of the insufflation catheter was placed 1 cm above the carina. The effects of TOI at flow rates of 0.2, 0.5, and 1.01/kg per min during and after CPR were examined in dogs with induced ventricular fibrillation. During CPR, adequate oxygenation and ventilation were maintained with TOI at flow rates of 0.5 and 1.0 1/kg per min, but not at 0.21/kg per min. After CPR, TOI was adequate to maintain oxygenation, but not ventilation. TOI alone did not prevent post-CPR hypercarbia in successfully resuscitated animals. Still, this study suggests that TOI might be useful as a temporary measure for emergency ventilation during CPR, especially in situations such as upper airway abnormalities, when mask ventilation or endotracheal intubation is not feasible.     

连续性血液净化治疗对心肺复苏术后患者脑复苏效果的影响

目的探讨连续性血液净化治疗（CBP）对心肺复苏术（CPR）后患者脑复苏效果的影响及其可能的机制。方法选取CPR术后脑复苏未成功的患者60例随机分为两组，每组30例，采用CBP＋原发病的综合治疗30例作治疗组。采用常规脱水、头部低温＋原发病的综合治疗的30例患者作对照组。观察两组患者脑复苏成功的时间、成功率。结果治疗组患者的脑复苏成功的时间较对照组明显缩短、脑复苏成功率明显高于对照组（P〈0．01），两组患者的死亡率无明显差异（P〉0．05）。结论连续性血液净化治疗对心肺复苏后患者能明显减轻脑水肿，缩短脑水肿的时间，提高脑复苏的成功率。     

Bispectral index (BIS) and suppression ratio (SR) as an early predictor of unfavourable neurological outcome after cardiac arrest

Introduction

Predicting the neurological outcome after cardiopulmonary resuscitation (CPR) is extremely difficult. We tested the hypothesis whether monitoring of bispectral index (BIS) and suppression ratio (SR) could serve as an early prognostic indicator of neurological outcomes after CPR.

Methods

Cerebral monitoring (BIS, SR) was started as soon as possible after initiation of CPR and was continued for up to 72 h. The functional neurological outcome was measured on day 3, day 7 and again one month after CPR via a clinical examination and assessment according to the cerebral performance category score (CPC).

Results

In total 79 patients were included. Of these, 26 patients (32.9%) survived the observation period of one month; 7 of them (8.9%) showed an unfavourable neurological outcome. These 7 patients had significantly lower median BIS values (25 [21;37] vs. 61 [51;70]) and higher SR (56 [44;64] vs. 7 [1;22]) during the first 4 h after the initiation of CPR. Using BIS < 40 as threshold criteria, unfavourable neurological outcome was predicted with a specificity of 89.5% and a sensitivity of 85.7%. The odds ratio for predicting an unfavourable neurological outcome was 0.921 (95% CI 0.853–0.985). The likelihood to remain in a poor neurological condition decreased by 7.9% for each additional point of BIS, on average.

Conclusion

Our results suggest that BIS and SR are helpful tools in the evaluation of the neurological outcomes of resuscitated patients. Nevertheless, therapeutic decisions have to be confirmed through further examinations due to the far-ranging consequences of false positive results.     

轻度阿尔茨海默病的PET与SPECT特征与对比

目的研究轻度阿尔茨海默病(AD)18F-FDG PET与99Tcm-ECD SPECT影像特征,并进行对比.方法受检者分为两组,正常对照组10例,轻度AD组 15例.利用ROI技术获得受检者的脑代谢比值(RARmetab)和脑血流比值(RARflow).结果与正常老年人比较,AD病人的RARmetab和RARflow减低,经统计学t检验均有显著性差异.结论轻度AD葡萄糖代谢影像特征是出现单侧顶叶、颞叶或颞顶叶代谢减低,额叶代谢保留在正常水平.SPECT脑血流显像特征与PET相似,但其灵敏度低于PET.     

Brain tissue oxygen pressure and cerebral metabolism in an animal model of cardiac arrest and cardiopulmonary resuscitation

OBJECTIVE: Direct measurement of brain tissue oxygenation (PbtO2) is established during spontaneous circulation, but values of PbtO2 during and after cardiopulmonary resuscitation (CPR) are unknown. The purpose of this study was to investigate: (1) the time-course of PbtO2 in an established model of CPR, and (2) the changes of cerebral venous lactate and S-100B. METHODS: In 12 pigs (12-16 weeks, 35-45 kg), ventricular fibrillation (VF) was induced electrically during general anaesthesia. After 4 min of untreated VF, all animals were subjected to CPR (chest compression rate 100/min, FiO2 1.0) with vasopressor therapy after 7, 12, and 17 min (vasopressin 0.4, 0.4, and 0.8 U/kg, respectively). Defibrillation was performed after 22 min of cardiac arrest. After return of spontaneous circulation (ROSC), the pigs were observed for 1h. RESULTS: After initiation of VF, PbtO2 decreased compared to baseline (mean +/- SEM; 22 +/- 6 versus 2 +/- 1 mmHg after 4 min of VF; P < 0.05). During CPR, PbtO2 increased, and reached maximum values 8 min after start of CPR (25 +/- 7 mmHg; P < 0.05 versus no-flow). No further changes were seen until ROSC. Lactate, and S-100B increased during CPR compared to baseline (16 +/- 2 versus 85 +/- 8 mg/dl, and 0.46 +/- 0.05 versus 2.12 +/- 0.40 microg/l after 13 min of CPR, respectively; P < 0.001); lactate remained elevated, while S-100B returned to baseline after ROSC. CONCLUSIONS: Though PbtO2 returned to pre-arrest values during CPR, PbtO2 and cerebral lactate were lower than during post-arrest reperfusion with 100% oxygen, which reflected the cerebral low-flow state during CPR. The transient increase of S-100B may indicate a disturbance of the blood-brain-barrier.     

小儿心肺复苏后脑血流及脑血管二氧化碳反应性的变化

目的观察心肺复苏后小儿脑血流变化特点,与脑损伤程度及预后的关系,脑血管二氧化碳收缩反应性变化。方法经颅多普勒超声(transcranial Doppler,TCD)动态监测心肺复苏后患儿35例,以左侧大脑中动脉(middle cerebral artery,MCA)和颈内动脉颅外段(extracranial internal carotid artery,EICA)为靶血管,根据复苏后12～24 h TCD频谱形态将患儿分为低灌流组、高灌流组和大致正常组。观察血流速度、脉动指数和MCA/EICA平均流速比值,同时做Glasgow昏迷评分。选择三组中气管插管机械通气的患儿26例,采用过度通气法进行脑血管CO_2收缩反应测定。结果低灌流组和高灌流组患儿最高Glasgow评分明显低于大致正常组(P＜0．05)；而死亡和放弃治疗自动出院病例数明显高于大致正常组(P＜0．01)。低灌流、高灌流组患儿的脑血管CO_2收缩反应性明显低于大致正常组患儿(P＜0．05)。结论TCD监测心肺复苏后患儿脑血流变化有助于了解脑灌流,评估预后,评价脑血管二氧化碳反应性；在缺乏脑血流监测的情况下,复苏后患者常规应用过度通气降颅压有加重脑缺氧的可能。