Devices used in cardiac arrest

Even the best conventional manual cardiopulmonary resuscitation (CPR) is highly inefficient, producing only a fraction of normal cardiac output. Over the past several decades, many therapeutic devices have been designed to improve on conventional CPR during cardiac arrest and increase the probability of survival. This article reviews several adjuncts and mechanical alternatives to conventional CPR for use during cardiac arrest. Recent clinical studies comparing conventional resuscitation techniques with the use of devices during cardiac arrest are reviewed, with a focus on clinical implications and directions for future research.     

Out-of-hospital unwitnessed cardiopulmonary collapse and no-bystander CPR: a practical addition to resuscitation termination guidelines

Cardiopulmonary resuscitation (CPR) provides possible survival from otherwise fatal cardiopulmonary collapse. Termination guidelines have been developed for use when resuscitation has no potential benefit for a victim. The purpose of this prospective cohort study was to determine if unwitnessed collapse combined with no-bystander cardiopulmonary resuscitation would support a decision to terminate attempted resuscitation. There were 541 patients analyzed during 6 months, with functional neurological survival the outcome of interest. There were no functional neurological survivors at hospital discharge among the 180 victims in the unwitnessed, no-bystander CPR subgroup (95% confidence interval [CI] 0.0%-2.1%). Functional neurological survival for witnessed collapse, bystander CPR was 6.0% (95% CI 2.8%-12.5%), for witnessed collapse, no-bystander CPR was 3.8% (95% CI 1.9%-7.7%), and for unwitnessed collapse, bystander CPR 1.3% (95% CI 0.2%-6.9%). With confirmation by further studies, unwitnessed collapse and lack of bystander CPR may be a practical addition to resuscitation termination guidelines.     

CPR quality improvement during in-hospital cardiac arrest using a real-time audiovisual feedback system

BACKGROUND: Cardiopulmonary resuscitation (CPR) quality during actual cardiac arrest has been found to be deficient in several recent investigations. We hypothesized that real-time feedback during CPR would improve the performance of chest compressions and ventilations during in-hospital cardiac arrest. METHODS: An investigational monitor/defibrillator with CPR-sensing and feedback capabilities was used during in-hospital cardiac arrests from December 2004 to December 2005. Chest compression and ventilation characteristics were recorded and quantified for the first 5 min of resuscitation and compared to a baseline cohort of arrest episodes without feedback, from December 2002 to April 2004. RESULTS: Data from 55 resuscitation episodes in the baseline pre-intervention group were compared to 101 resuscitations in the feedback intervention group. There was a trend toward improvement in the mean values of CPR variables in the feedback group with a statistically significant narrowing of CPR variable distributions including chest compression rate (104+/-18 to 100+/-13 min(-1); test of means, p=0.16; test of variance, p=0.003) and ventilation rate (20+/-10 to 18+/-8 min(-1); test of means, p=0.12; test of variance, p=0.04). There were no statistically significant differences between the groups in either return of spontaneous circulation or survival to hospital discharge. CONCLUSIONS: Real-time CPR-sensing and feedback technology modestly improved the quality of CPR during in-hospital cardiac arrest, and may serve as a useful adjunct for rescuers during resuscitation efforts. However, feedback specifics should be optimized for maximal benefit and additional studies will be required to assess whether gains in CPR quality translate to improvements in survival.     

Minimally invasive direct cardiac massage versus closed-chest cardiopulmonary resuscitation in a porcine model of prolonged ventricular fibrillation cardiac arrest

Open chest cardiac massage has been shown to be superior to closed-chest cardiopulmonary resuscitation for both hemodynamics produced during resuscitation and ultimate resuscitation success. The inexperience of many rescuers with emergency thoracotomy, along with the associated morbidity contributes to the continued reluctance in the use of invasive cardiopulmonary resuscitation techniques. A device has been developed for performing 'minimally invasive' direct cardiac massage. This technique was compared to standard closed-chest CPR for resuscitation results in 20 swine during prolonged ventricular fibrillation cardiac arrest. Minimally invasive direct cardiac massage was superior to closed-chest CPR for return of spontaneous circulation (7/10 vs. 2/10; P<0.02) and coronary perfusion pressure at 30 min of CPR (17+/-9 vs. 6+/-6 mmHg; P<0.05). No significant injuries altering outcome were found with the invasive device. Throughout most of the time course of the study no significant differences in end-tidal expired carbon dioxide levels were noted. Nor were there any differences in 24-h survival. Improvements in assuring proper placement of the device on the epicardium should make this technique a potent advanced cardiac life support adjunct.     

CPR decision making and older adults: clinical implications

Originally developed in 1960 as an emergency intervention for individuals who unexpectedly went into cardiac arrest, cardiopulmonary resuscitation (CPR) is now in widespread use. With broader use of CPR over the past several decades, some limitations and unintended consequences of the procedure have been identified. In addition, accumulated data have demonstrated low probabilities of survival and uneven success rates of CPR for certain subgroups. Despite advances in the understanding of CPR outcomes, the general public and many health professionals significantly overestimate the benefits and underestimate any negative consequences. As a result, CPR decision making is often based on incomplete or inaccurate information. This article discusses the "rest of the story" about CPR, namely the existing evidence about CPR survival and potential complications of CPR. The article also highlights how nurses can help promote informed decision making about CPR to older adults and their families.     

Bispectral index monitoring during cardiopulmonary resuscitation repeated twice within 8 days in the same patient: a case report

Research on cardiac resuscitation has led to various changes in the techniques and drug administration involved in modern advanced life support. Besides improving primary cardiac survival, interest is increasingly focused on a favourable neurological outcome. However, until now there has been no on-site equipment to support the clinical observations of the cardiopulmonary resuscitation (CPR) team. Bispectral index (BIS) monitoring has been used for avoiding awareness during anaesthesia for many years. We report a case of a 68-year-old patient suffering twice from cardiac arrest due to thromboembolism within a few days. While the first cardiac resuscitation was survived without neurological consequences, the patient died after the second event. Both resuscitation events were monitored using the BIS. We discuss the course of BIS values and their possible contribution to the prediction of outcome.     

In-hospital cardiac arrest: Is outcome related to the time of arrest?

BACKGROUND: Whether outcome from in-hospital cardiopulmonary resuscitation (CPR) is poorer when it occurs during the night remains controversial. This study examined the relationship between CPR during the various hospital shifts and survival to discharge. METHODS: CPR attempts occurring in a tertiary hospital with a dedicated, certified resuscitation team were recorded prospectively (Utstein template guidelines) over 24 months. Medical records and patient characteristics were retrieved from patient admission files. RESULTS: Included were 174 in-hospital cardiac arrests; 43%, 32% and 25% in morning evening and night shifts, respectively. Shift populations were comparable in demographic and treatment related variables. Asystole (p < 0.01) and unwitnessed arrests (p = 0.05) were more common during the night. Survival to discharge was poorer following night shift CPR than following morning and evening shift CPR (p = 0.04). When asystole (being synonymous with death) was excluded from the analysis, the odds of survival to discharge was not higher for witnessed compared to unwitnessed arrest but was 4.9 times higher if the cardiac arrest did not occur during the night shift (p = 0.05, logistic regression). The relative risk of eventual in-hospital death for patients with return of spontaneous circulation (ROSC) following night shift resuscitation was 1.9 that of those with ROSC following morning or evening resuscitation (Cox regression). CONCLUSIONS: Although unwitnessed arrest is more prevalent during night shift, resuscitation during this shift is associated with poorer outcomes independently of witnessed status. Further research is required into the causes for the increased mortality observed after night shift resuscitation.     

In-hospital cardiac arrest: characteristics and outcome after implementation of systematic practice-oriented training

Survival after in-hospital cardiac arrest (CA) has been reported to be surprisingly low without any major improvement during the last decade. Cardiopulmonary resuscitation (CPR) quality affects survival after CA, and specific education is necessary for health care professionals participating in CPR. Decisions regarding CPR and do not attempt resuscitation (DNAR) orders remain demanding, as does including patients in the process. Addressed training regarding CPR/DNAR orders is necessary to improve the CPR/DNAR decision process used by physicians. The aim of this retrospective study is to evaluate the clinical impact (return of spontaneous circulation and 21-day survival after CA) of an intervention within one single hospital, including a systematic education of all health care professionals in CPR. In total, there were 33 in-hospital CAs before (12 months) and 176 after (36 months) the intervention. No significant difference was found between the 2 calendar periods.     

Comparison of mechanical techniques of cardiopulmonary resuscitation: survival and neurologic outcome in dogs

Three currently available mechanical devices for cardiopulmonary resuscitation (CPR) were compared using a canine cardiac arrest model. Twenty-four-hour survival without neurologic deficit was the goal. A group of 30 large mongrel dogs was divided equally among Thumper CPR, simultaneous compression and ventilation (SCV) CPR, and vest CPR. Ventricular fibrillation was induced electrically, and after 3 minutes of no intervention, one of the three types of mechanical CPR was performed for 17 minutes. SCV CPR and vest CPR produced significantly greater aortic and right atrial systolic pressures than Thumper CPR (P less than .03). The SCV CPR technique also produced significantly higher aortic diastolic pressure and right atrial diastolic pressure than either of the other methods (P less than .03). However, coronary perfusion pressure was not different among the three mechanical methods. No differences in immediate resuscitation, 24-hour survival, or neurologic deficit scores at 24 hours were found. Neither SCV nor the vest techniques of CPR appear better for survival or neurologic outcome than standard cardiopulmonary resuscitation performed with the Thumper.     

Available ventilation monitoring methods during pre-hospital cardiopulmonary resuscitation

High quality cardiopulmonary resuscitation (CPR) in the pre-hospital setting has been associated with improved survival rates during cardiopulmonary arrest (CPA). Recent documentation of hyperventilation associated deterioration in hemodynamics during CPR, suggests that guided or controlled ventilation strategies may contribute to improved hemodynamics and increased survival. This article briefly reviews the mechanical methods, advantages, and disadvantages of the available ventilation monitoring methods currently available for clinical use, with an emphasis on pre-hospital implementation. We recommend that more objective measurement of ventilation during CPR be performed, with emphasis on a strategy for measuring both attempted ventilation frequency (f) and delivered tidal volume (VT). The use of improved thoracic impedance pneumography and capnography are appealing for such monitoring because of the widespread availability, but modifications to existing software and clinical data compared to a clinical standard would be required before general acceptance is possible. Other methods listed may offer advantages over these in select circumstances.     

Could the survival and outcome benefit of adrenaline also be dependent upon the presence of gasping upon arrival of emergency rescuers?

A recent systematic review and meta-analysis of randomized controlled trials of adrenaline use during resuscitation of out-of-hospital cardiac arrest found no benefit of adrenaline in survival to discharge or neurological outcomes. It did, however, find an advantage of standard dose adrenaline (SDA) over placebo and high dose adrenaline over SDA in overall survival to admission and return of spontaneous circulation (ROSC), which was also consistent with previous reviews. As a result, the question that remains is "Why is there no difference in the rate of survival to discharge when there are increased rates of ROSC and survival to admission in patients who receive adrenaline?" It was suggested that the lack of efficacy and effectiveness of adrenaline may be confounded by the quality of cardiopulmonary resuscitation (CPR) during cardiac arrest, which has been demonstrated in animal models. CPR quality was not measured or reported in the included randomized controlled trials. However, the survival and outcome benefit of adrenaline may also depend upon the presence of witnessed gasping and/or gasping upon arrival of emergency rescuers, which is a critical factor not accounted for in the analyses of the cited animal studies that allowed gasping but showed the survival and neurological outcome benefits of adrenaline use. Moreover, without the aid of gasping, very few rescuers can provide high-quality CPR. Also, age and the absence of gasping observed by bystanders and/or upon arrival of emergency- rescuers may be important factors in the determination of whether vasopressin instead of adrenaline should be used first.     

Resuscitating an idea: prone CPR

Cardiopulmonary resuscitation (CPR) is widely recognized as an essential part of the medical response to cardiac arrest. Traditional ('basic') CPR has remained essentially unchanged for 40 years despite major problems with training and performance, and survival rates from out-of-hospital cardiac arrest remain disappointingly low, despite massive resources devoted to CPR training and public awareness. More than a decade ago, an article described an alternative method-prone CPR-which offered many potential advantages over traditional CPR, including much simpler training and increased likelihood of actual performance by bystanders. The article received little notice at the time; however, the method of prone CPR merits further consideration based on a number of subsequent supporting studies and case reports. Prone CPR may represent a superior alternative to traditional CPR; research into its effectiveness should be given high priority.     

心肺复苏教学及实践智能化辅助技术的研究进展

心肺复苏(cardiopulmonary resuscitation,CPR)是抢救生命的关键技术之一。本文旨在多方面探究CPR培训的智能化研究现状,并为未来CPR教学和实践的智能化发展方向提供建议。在web of science核心库近五年的文章中搜索CPR训练和CPR智能化设备,获得31篇相关文献。CPR智能化涉及教学、辅助、统计和监测等多方面。现实增强(AR)技术满足了CPR培训互动中环境模拟等新需求。智能设备及新算法提高CPR的培训质量。本文简述了应对心脏骤停一些需要注意的问题。健全的急救保障系统对提高心脏骤停患者的生存率具有很大帮助。     

Cardiopulmonary resuscitation for cardiac arrest: the importance of uninterrupted chest compressions in cardiac arrest resuscitation

Over the last decade, the importance of delivering high-quality cardiopulmonary resuscitation (CPR) for cardiac arrest patients has become increasingly emphasized. Many experts are in agreement concerning the appropriate compression rate, depth, and amount of chest recoil necessary for high-quality CPR. In addition to these factors, there is a growing body of evidence supporting continuous or uninterrupted chest compressions as an equally important aspect of high-quality CPR. An innovative resuscitation protocol, called cardiocerebral resuscitation, emphasizes uninterrupted chest compressions and has been associated with superior rates of survival when compared with traditional CPR with standard advanced life support. Interruptions in chest compressions during CPR can negatively impact outcome in cardiac arrest; these interruptions occur for a range of reasons, including pulse determinations, cardiac rhythm analysis, electrical defibrillation, airway management, and vascular access. In addition to comparing cardiocerebral resuscitation to CPR, this review article also discusses possibilities to reduce interruptions in chest compressions without sacrificing the benefit of these interventions.     

心肺复苏教学及实践智能化辅助技术的研究进展

心肺复苏(cardiopulmonary resuscitation,CPR)是抢救生命的关键技术之一。本文旨在多方面探究CPR培训的智能化研究现状,并为未来CPR教学和实践的智能化发展方向提供建议。在web of science核心库近五年的文章中搜索CPR训练和CPR智能化设备,获得31篇相关文献。CPR智能化涉及教学、辅助、统计和监测等多方面。现实增强(AR)技术满足了CPR培训互动中环境模拟等新需求。智能设备及新算法提高CPR的培训质量。本文简述了应对心脏骤停一些需要注意的问题。健全的急救保障系统对提高心脏骤停患者的生存率具有很大帮助。     

Capnography as a predictor of the return of spontaneous circulation

EtCO2 monitoring is a valuable tool for clinical management of patients in cardiac arrest, near-arrest and post-arrest. During cardiac arrest, EtCO2 levels fall abruptly at the onset of cardiac arrest, increase after the onset of effective CPR and return to normal at return of spontaneous circulation (ROSC). During effective CPR, end-tidal CO2 has been shown to correlate with cardiac output, coronary perfusion pressure, efficacy of cardiac compression, ROSC and even survival. Colorimetric detectors (shown to correlate with infrared capnometry) have been shown to have prognostic value in both adult and pediatric CPR. The higher the initial value of EtCO2, the greater was short-term survival. EtCO2 is a useful tool during patient resuscitation for evaluating the current and potential effects of treatment, and could be potentially useful in determining when to terminate resuscitation efforts.     

Cardiopulmonary resuscitation, brain blood flow, and neurologic recovery

A review of survival rates and neurologic outcome after cardiac resuscitation indicates the importance of rapid initiation of cardiopulmonary resuscitation (CPR) and of finding ways to further improve cerebral blood flow during CPR. Mechanisms for generating blood flow to the brain during CPR and experimental strategies for enhancing cerebral viability are discussed.     

One-year survival and neurological outcome after pediatric cardiopulmonary resuscitation

OBJECTIVE: Reported survival after cardiopulmonary resuscitation (CPR) in children varies considerably. We aimed to identify predictors of 1-year survival and to assess long-term neurological status after in- or outpatient CPR. DESIGN: Retrospective review of the medical records and prospective follow-up of CPR survivors. SETTING: Tertiary care pediatric university hospital. PATIENTS AND METHODS: During a 30-month period, 89 in- and outpatients received advanced CPR. Survivors of CPR were prospectively followed-up for 1 year. Neurological outcome was assessed by the Pediatric Cerebral Performance Category scale (PCPC). Variables predicting 1-year survival were identified by multivariable logistic regression analysis. INTERVENTIONS: None. RESULTS: Seventy-one of the 89 patients were successfully resuscitated. During subsequent hospitalization do-not-resuscitate orders were issued in 25 patients. At 1 year, 48 (54%) were alive, including two of the 25 patients with out-of-hospital CPR. All patients died, who required CPR after trauma or near drowning, when CPR began >10 min after arrest or with CPR duration >60 min. Prolonged CPR (21-60 min) was compatible with survival (five of 19). At 1 year, 77% of the survivors had the same PCPC score as prior to CPR. Predictors of survival were location of resuscitation, CPR during peri- or postoperative care, and duration of resuscitation. A clinical score (0-15 points) based on these three items yielded an area under the ROC of 0.93. CONCLUSIONS: Independent determinants of long-term survival of pediatric resuscitation are location of arrest, underlying cause, and duration of CPR. Long-term survivors have little or no change in neurological status.     

Inhospital CPR 25 years later: why has survival decreased?

Since the introduction of cardiopulmonary resuscitation (CPR) 25 years ago, there have been many advances in cardiopulmonary technology and in our understanding of the factors leading to a successful outcome. Despite these advances, our study of outcomes in 88 patients having CPR at Johns Hopkins Hospital in 1981 revealed a 14% survival rate to discharge compared with 24% from the same hospital from 1959 to 1961. We found that 74% of the 46 patients who initially survived CPR died before discharge. In addition, two of 12 survivors at discharge were dead one week later and one was in a persistent vegetative state three years after CPR. Our findings suggest that this technology, once meant to be applied when cardiac arrest was sudden and unexpected, is now being applied to patients regardless of underlying condition or prognosis. A follow-up survey of 63 Maryland hospitals revealed that many lacked formal plans for CPR management or education. We recommend that a comprehensive approach to CPR be adopted by all hospitals, involving education regarding appropriate patient selection, assurance of skilled application and backup care for survivors, and a mechanism for routinely monitoring outcome.