Effect of phased chest and abdominal compression-decompression cardiopulmonary resuscitation on myocardial and cerebral blood flow in pigs

OBJECTIVE: This study was designed to assess the effects of a phased chest and abdominal compression-decompression cardiopulmonary resuscitation (CPR) device, Lifestick, vs. standard CPR on vital organ blood flow in a porcine CPR model. DESIGN: Prospective, randomized laboratory investigation using an established porcine model with instrumentation for measurement of hemodynamic variables, vital organ blood flow, blood gases, and return of spontaneous circulation. SETTING: University hospital research laboratory. SUBJECTS: Twelve domestic pigs. INTERVENTIONS: After 4 mins of untreated ventricular fibrillation, either the Lifestick CPR device (n = 6) or standard CPR (n = 6) was started and maintained for an additional interval of 6 mins before attempting defibrillation. MEASUREMENTS AND MAIN RESULTS: During CPR, but before epinephrine, use of the Lifestick CPR device resulted in significantly higher (p < .05) mean (+/- SD) coronary perfusion pressure (23+/-9 vs. 10+/-7 mm Hg), cerebral perfusion pressure (29+/-11 vs. 18+/-10 mm Hg), mean arterial pressure (49+/-10 vs. 36+/-13 mm Hg), end-tidal carbon dioxide (32+/-11 vs. 20+/-7 mm Hg), left ventricular myocardial blood flow (44+/-19 vs. 19+/-12 mL x min(-1) x 100 g(-1)), and total cerebral blood flow (29+/-10 vs. 14+/-12 mL x min(-1) x 100 g(-1)). After 45 microg/kg epinephrine, hemodynamic and vital organ blood flow variables increased to comparable levels in both groups. CONCLUSIONS: Compared with standard CPR, the Lifestick CPR device increased significantly hemodynamic variables and vital organ blood flow during CPR before epinephrine administration.     

徒手胸外心脏按压复苏法的进展

心肺复苏 ( CPR)自创立至今 ,已走过了漫长而曲折的道路 ,其方法和机制经过众多实验及临床研究人员的共同努力 ,已取得了很大的进展。现将其发展趋势综述如下。1　标准 CPRKouwenhoven〔1〕于 196 0年报告 ,有节律地按压动物胸骨可产生动脉压搏动 ,并在长时间心室纤颤后使用闭胸电除颤成功 ,首创胸外心脏按压复苏法救治心性猝死成功。它以掌根部挤压胸骨中下段 ,使胸骨下陷 3～ 4( 5 ) cm,频率为 6 0～ 80 ( 10 0 )次 / min,并相继与 PeterSafar发表的口对口呼吸相配合。当时认为有节律地按压胸骨可使胸骨与脊柱间的心脏被挤压 ,关闭房…     

胸腹按压心肺复苏术对猝死患者生存率的影响

动物实验和临床研究均已证实 ,标准心肺复苏术 ( CPR)是依靠外力 ,通过挤压胸腔建立人工循环和呼吸 ,为患者提供基础生命支持。最近 ,根据动物实验和数学模型〔1 ,2〕 ,提出了间插腹部按压式CPR(胸腹 CPR)和主动按压去按压式CPR,认为其可以改善血液循环。但这在人类评价甚少。为研究胸腹 CPR对猝死患者循环和生存率的影响 ,我们将其与标准 CPR进行临床对比 ,报告如下。1　对象与方法1.1　病例 :1996年 3月— 2 0 0 1年 12月在我院急诊科就诊和在心脏科住院期间发生猝死的患者 16 6例 ,其中男 98例 ,女 6 8例 ;年龄 11～ 86岁 ,平均 …     

Chest injuries after active compression-decompression cardiopulmonary resuscitation (ACD-CPR) in cadavers

In a prospective study of 38 cadavers of patients older than 18 without previous chest injury or cardiopulmonary resuscitation (CPR), active compression-decompression (ACD) resuscitation manoeuvres were performed to determine possible factors influencing sternal and/or rib fractures. ACD was performed for 60 s, with compression and decompression forces being continuously recorded. A stepwise logistic regression analysis was applied. Factors analyzed were age, gender, use of a compression cushion beneath the piston of the ACD device (Ambu CardioPump), and maximal compression and decompression forces. After ACD, the cadavers were autopsied and thoracic injuries were assessed. There was a significant correlation between sternal fractures and gender (P = 0.008), and between rib fractures and age (P = 0.008). Women were found to have a higher risk for sternal fractures, whereas older patients had a higher risk for rib fractures. Maximal compression force was another factor in sternal and/or rib fracture (P = 0.048). Even though a significantly higher incidence of sternal fractures was observed when the compression cushion was used (P = 0.045), inclusion of this variable in the regression analysis only marginally improved the prediction for correct classification of sternal fractures. In conclusion, when well controlled ACD-CPR is performed in cadavers, age is the most important factor determining the incidence of rib fracture. Sternal fractures were more common in female cadavers.     

Successful transdiaphragmatic cardiac resuscitation through midline abdominal incision in patient with flail chest.

This case report describes a transdiaphragmatic approach through an already present vertical midline abdominal incision for performing internal cardiac compressions in a 30-year-old male road accident victim. The patient had a flail chest with haemopneumothorax and haemoperitoneum. Exploratory laparotomy followed by splenectomy was performed under general anaesthesia but the patient developed a witnessed cardiac arrest in postoperative period. Successful resuscitation using internal cardiac compression by a transdiaphragmatic approach through the midline abdominal incision that was not extended proximally is described.     

Cardiopulmonary resuscitation with simultaneous chest and abdominal compression: comparative study in humans

To assess the efficacy of the simultaneous application of chest and abdominal compression (SCAC) in cardiopulmonary resuscitation (CPR), we performed a prospective study on 18 patients shortly after cardiac arrest. Three different CPR procedures were carried out consecutively: (1) Standard CPR; (2) CPR interposed with abdominal compression (IAC-CPR); and (3) SCAC-CPR. Standard CPR was repeated at the end of each sequence. Thoracic aortic and right atrial pressures were recorded during maneuvers and no vasoactive drugs were administered. Systolic aortic pressures were 39.02 +/- 21 mmHg, 63.6 +/- 21 mmHg and 94.04 +/- 21 mmHg during standard CPR, IAC-CPR and SCAC-CPR, respectively (P less than 0.001). There was no evidence of intra-abdominal injury in the eight autopsies performed. We have reached the conclusion that the use of SCAC-CPR on humans does produce greater intravascular pressure and we recommend this technique as a possible alternative to standard CPR.     

主动按压减压结合高频通气对心肺复苏犬的循环效应影响

目的　比较标准心肺复苏、主动按压减压心肺复苏、主动按压减压结合高频通气心肺复苏三种复苏法对心肺复苏循环效应影响 ;评价主动按压减压结合高频通气用于心肺复苏的可行性。方法　将9条犬经电击致颤制成心搏骤停模型 ,每只犬先后实施三种复苏法 ,①标准心肺复苏 ;②主动按压减压心肺复苏 ;③主动按压减压结合高频通气心肺复苏 ,实验顺序由随机法确定 ,每种复苏方法进行 5min ,待循环动力学稳定后记录收缩压、舒张压、心输出量。结果　收缩压、舒张压、心输出量均为主动按压减压结合高频通气模式大于主动按压减压心肺复苏模式 (P <0 0 1) ;主动按压减压心肺复苏模式大于标准心肺复苏模式 (P <0 0 1)。标准心肺复苏模式和主动按压减压心肺复苏模式胸外按压停顿期血压降至零 ,而主动按压减压结合高频通气心肺复苏模式血压持续稳定。结论　主动按压减压心肺复苏优于标准心肺复苏模式。主动按压减压结合高频通气心肺复苏模式既可产生较高的动脉血压、心输出量 ,又可提供充分的气体交换 ,值得进一步研究和推广应用     

Effect of active compression-decompression resuscitation (ACD-CPR) on survival: a combined analysis using individual patient data.

Active compression decompression resuscitation (ACD-CPR) has been developed as an alternative to standard cardiopulmonary resuscitation (S-CPR). To determine the effect of ACD-CPR on survival and neurologic outcome in patients with out-of-hospital cardiac arrest, this combined analysis involved individual patient data from 2866 patients from seven separate randomized prospective prehospital studies who had received ACD-CPR or S-CPR after out-of-hospital cardiac arrest in seven international sites. Significant improvement in 1-h survival (odds ratio (OR) = 0.83; confidence interval (CI): 0.695-0.99; P < 0.05) was found with ACD-CPR (n = 1410) versus S-CPR (n = 1456). The odds ratio for hospital discharge after ACD-CPR was similar (OR = 0.82; CI: 0.609-1.107, P = NS), but this finding was not statistically significant. Using the chi2-test for trend, there was a significant improvement in overall survival with ACD-CPR (P < 0.05) versus S-CPR. This improvement was largely due to the influence of results from one study site. Neurological outcome and complication rates were comparable between groups. Further study is needed to determine which emergency medical services systems may benefit from out-of-hospital use of ACD-CPR.     

Simulated mouth-to-mouth ventilation and chest compressions (bystander cardiopulmonary resuscitation) improves outcome in a swine model of prehospital pediatric asphyxial cardiac arrest.

OBJECTIVE: To compare the efficacy of four methods of simulated single-rescuer bystander cardiopulmonary resuscitation (CPR) in a clinically relevant swine model of prehospital pediatric asphyxial cardiac arrest. DESIGN: Prospective, randomized study. SUBJECTS: Thirty-nine anesthetized domestic piglets. INTERVENTIONS: Asphyxial cardiac arrest was produced by clamping the endotracheal tubes of the piglets. For 8 mins of simulated bystander CPR, animals were randomly assigned to the following groups: group 1, chest compressions and simulated mouth-to-mouth ventilation (FI(O2) = 0.17, FI(CO2) = 0.04) (CC+V); group 2, chest compressions only (CC); group 3, simulated mouth-to-mouth ventilation only (V); and group 4, no CPR (control group). Standard advanced life support was then provided, simulating paramedic arrival. Animals that were successfully resuscitated received 1 hr of intensive care support and were observed for 24 hrs. MEASUREMENTS AND MAIN RESULTS: Electrocardiogram, aortic blood pressure, right atrial blood pressure, and end-tidal CO2 were monitored continuously until the intensive care period ended. Arterial and mixed venous blood gases were measured at baseline, 1 min after cardiac arrest, and 7 mins after cardiac arrest. Minute ventilation was determined during each minute of bystander CPR. Survival and neurologic outcome were determined. Twenty-four-hour survival was attained in eight of 10 group 1 (CC+V) piglets vs. three of 14 group 2 (CC) piglets (p < or = .01), one of seven group 3 (V) piglets (p < or = .05), and two of eight group 4 (control) piglets (p < or = .05). Twenty-four-hour neurologically normal survival occurred in seven of 10 group 1 (CC+V) piglets vs. one of 14 group 2 (CC) piglets (p < or = .01), one of seven group 3 (V) piglets (p < or = .05), and none of eight group 4 (control) piglets (p < or = .01). Arterial oxygenation and pH were markedly better during CPR in group 1 than in group 2. Within 5 mins of bystander CPR, six of 10 group 1 (CC+V) piglets attained sustained return of spontaneous circulation vs. only two of 14 group 2 (CC) piglets and none of the piglets in the other two groups (p < or = .05 for all groups). CONCLUSIONS: In this pediatric asphyxial model of prehospital single-rescuer bystander CPR, chest compressions plus simulated mouth-to-mouth ventilation improved systemic oxygenation, coronary perfusion pressures, early return of spontaneous circulation, and 24-hr survival compared with the other three approaches.     

Active compression-decompression cardiopulmonary resuscitation (CPR) versus standard CPR for cardiac arrest patients: a meta-analysis

BACKGROUND:

Active compression-decompression cardiopulmonary resuscitation (ACDCPR) has been popular in the treatment of patients with cardiac arrest (CA). However, the effect of ACD-CPR versus conventional standard CPR (S-CRP) is contriversial. This study was to analyze the efficacy and safety of ACD-CPR versus S-CRP in treating CA patients.

METHODS:

Randomized or quasi-randomized controlled trials published from January 1990 to March 2011 were searched with the phrase “active compression-decompression cardiopulmonary resuscitation and cardiac arrest” in PubMed, EmBASE, and China Biomedical Document Databases. The Cochrane Library was searched for papers of meta-analysis. Restoration of spontaneous circulation (ROSC) rate, survival rate to hospital admission, survival rate at 24 hours, and survival rate to hospital discharge were considered primary outcomes, and complications after CPR were viewed as secondary outcomes. Included studies were critically appraised and estimates of effects were calculated according to the model of fixed or random effects. Inconsistency across the studies was evaluated using the I2 statistic method. Sensitivity analysis was made to determine statistical heterogeneity.

RESULTS:

Thirteen studies met the criteria for this meta-analysis. The studies included 396 adult CA patients treated by ACD-CPR and 391 patients by S-CRP. Totally 234 CA patients were found out hospitals, while the other 333 CA patients were in hospitals. Two studies were evaluated with high-quality methodology and the rest 11 studies were of poor quality. ROSC rate, survival rate at 24 hours and survival rate to hospital discharge with favorable neurological function indicated that ACD-CPR is superior to S-CRP, with relative risk (RR) values of 1.39 (95% CI 0.99–1.97), 1.94 (95% CI 1.45–2.59) and 2.80 (95% CI 1.60–5.24). No significant differences were found in survival rate to hospital admission and survival rate to hospital discharge for ACD-CPR versus S-CRP with RR values of 1.06 (95% CI 0.76–1.60) and 1.00 (95% CI 0.73–1.38).

CONCLUSION:

Quality controlled studies confirmed the superiority of ACD-CPR to S-CRP in terms of ROSC rate and survival rate at 24 hours. Compared with S-CRP, ACD-CPR could not improve survival rate to hospital admission or survival rate to hospital discharge.KEY WORDS: Active compression-decompression, Cardiopulmonary resuscitation, Cardiac arrest, Meta-analysis     

3:1 Compression to ventilation ratio versus continuous chest compression with asynchronous ventilation in a porcine model of neonatal resuscitation

Objective

In contrast to the resuscitation guidelines of children and adults, guidelines on neonatal resuscitation recommend synchronized 90 chest compressions with 30 manual inflations (3:1) per minute in newborn infants. The study aimed to determine if chest compression with asynchronous ventilation improves the recovery of bradycardic asphyxiated newborn piglets compared to 3:1 Compression:Ventilation cardiopulmonary resuscitation (CPR).

Intervention and measurements

Term newborn piglets (n = 8/group) were anesthetized, intubated, instrumented and exposed to 45-min normocapnic hypoxia followed by asphyxia. Protocolized resuscitation was initiated when heart rate decreased to 25% of baseline. Piglets were randomized to receive resuscitation with either 3:1 compressions to ventilations (3:1 C:V CPR group) or chest compressions with asynchronous ventilations (CCaV) or sham. Continuous respiratory parameters (Respironics NM3^®), cardiac output, mean systemic and pulmonary artery pressures, and regional blood flows were measured.

Main results

Piglets in 3:1 C:V CPR and CCaV CPR groups had similar time to return of spontaneous circulation, survival rates, hemodynamic and respiratory parameters during CPR. The systemic and regional hemodynamic recovery in the subsequent 4 h was similar in both groups and significantly lower compared to sham-operated piglets.

Conclusion

Newborn piglets resuscitated by CCaV had similar return of spontaneous circulation, survival, and hemodynamic recovery compared to those piglets resuscitated by 3:1 Compression:Ventilation ratio.     

腹部提压心肺复苏法对呼吸骤停猪肺通气的实验研究

虽然现代化医疗条件越来越先进,但院外心搏、呼吸骤停的复苏成功率仍然不容乐观.对于肺源性心搏骤停患者而言,当无条件建立人工气道时,尤其是在经气管插管连接呼吸器通气前,尽早维持有效的肺通气极为重要[1].     

The first European pre-hospital active compression-decompression (ACD) cardiopulmonary resuscitation workshop: a report and a review of ACD-CPR

Active compression-decompression cardiopulmonary resuscitation (ACD-CPR) has been evaluated in animal cardiac arrest models and in human outcome studies. Blood flow to the brain and heart is significantly increased during ACD-CPR compared to standard CPR. Transoesophageal Doppler analysis indicates that ACD-CPR increases left ventricular blood volume, velocity of blood flow through the mitral valve (82–140%), and stroke volume (85%). Pressures, such as coronary perfusion-, systolic-, mean-, and diastolic aortic pressures, ETCO₂, and tidal volume generated by chest compression and decompression, increase during ACD-CPR compared to standard CPR. Prehospital outcome studies have shown both positive and no extra benefit of ACD-CPR on return of spontaneous circulation, hospital admission, and discharge rates. The ACD-CPR method should be evaluated in patients with witnessed arrest receiving bystander CPR who are found in ventricular fibrillation and do not respond to the three initial DC shocks. There is no evidence that ACD-CPR is worse than standard CPR. Appropriate ACD-CPR training using a standardized curriculum must preceed its implementation. Long-term neurologic outcome studies are needed.