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Gordon A Ewy

Publications and source records attributed to Gordon A Ewy.

At least 19 recordsLinked to original sources
PubMed2006

Eighth grade students become proficient at CPR and use of an AED following a condensed training programme.

OBJECTIVE: To evaluate a new, 1-h, condensed training programme to teach continuous chest compression cardiopulmonary resuscitation (CCC-CPR) and automated external defibrillator (AED) skills to a cohort of eight grade public school students. METHODS RESULTS: Thirty-three eligible subjects completed the programme; mean age 13.7 years; 48.5% female. Eight participants reported some prior training in CPR and AED use. Following initial training, 29/33 (87.8%) subjects demonstrated proficiency at CCC-CPR and AED application/operation in a mock adult cardiac arrest scenario. At four-weeks, 28/33 (84.8%) subjects demonstrated skill retention in similar scenario testing. Subjects also showed improvement in written knowledge regarding AED use as shown by scores on an AHA based written exam (60.9% versus 77.3%; p<0.001). CONCLUSION: With our focused, condensed training program, eighth grade public school students became proficient in CCC-CPR and AED use. This is the first study to document the ability of middle school students to learn and retain CCC-CPR and AED skills for adult sudden cardiac arrest victims with such a curriculum.

Adolescent↗
PubMed2006

Single rescuer cardiopulmonary resuscitation: can anyone perform to the guidelines 2000 recommendations?

BACKGROUND: The Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care recommend that for adult cardiac arrest the single rescuer performs "two quick breaths followed by 15 chest compressions." This cycle is continued until additional help arrives. Previous studies have shown that lay persons and medical students take 16 +/- 1 and 14 +/- 1 s, respectively, to perform these "two quick breaths." The purpose of this study was to determine the time required for trained professional paramedic firefighters to deliver these two breaths and the effects that any increase in the time it takes to perform rescue breathing would have on the number of chest compressions delivered during single rescuer BLS CPR. We hypothesized that trained professional rescuers would also take substantially longer then the Guidelines recommendation for delivering the two rescue breaths before every 15 compressions during simulated single rescuer BLS CPR. METHODS: Twenty-four paramedic firefighters currently certified to perform BLS CPR were evaluated for their ability to deliver the two recommended breaths within 4 s according to the AHA 2000 CPR Guidelines. Alternatively, a simplified technique of continuous chest compression BLS CPR (CCC) was also taught and compared with standard BLS CPR (STD). Without revealing the purpose of the study the paramedics were asked to perform single rescuer BLS CPR on a recording Resusci Anne while being videotaped. RESULTS: The mean length of time needed to provide the "two quick breaths" during STD-CPR was 10 +/- 1 s. The mean number of chest compressions/min delivered with AHA BLS CPR was only 44 +/- 2. Continuous chest compression CPR resulted in 88 +/- 5 compressions delivered per minute (STD versus CCC; p < 0.0001). CONCLUSIONS: Trained professional emergency rescue workers perform rescue breathing somewhat faster than lay rescuers or medical students, but still require two and one half times longer than recommended. The time required to perform these breaths significantly decreases the number of chest compressions delivered per minute. This may affect outcome as experimental studies have shown that more than 80 compressions delivered per minute are necessary for survival from prolonged cardiac arrest.

Allied Health Personnel↗
PubMed2006

Cardiocerebral resuscitation for cardiac arrest.

Survival rates from out-of-hospital cardiac arrest continue to be low despite periodic updates in the Guidelines for Emergency Medical Services and periodic improvements such as the addition of automatic external defibrillators (AEDs). The low incidence of bystander cardiopulmonary resuscitation (CPR), substantial time without chest compressions throughout the resuscitation effort, and a lack of response to initial defibrillation after prolonged ventricular fibrillation contribute to these unacceptably poor results. Resuscitation guidelines are only revised every 5 to 7 years and can be difficult to change because of the lack of randomized controlled trials in humans. Such trials are rare because of a number of logistical difficulties, including the problem of obtaining informed consent. An alternative approach to advancing resuscitation science is for evidence-based demonstration projects in areas that have adequate records, so that one may determine whether the new approach improves survival. This is reasonable because the current guidelines make provisions for deviations under certain local circumstances or as directed by the emergency medical services medical director. A wealth of experimental evidence indicates that interruption of chest compressions for any reason in patients with cardiac arrest is deleterious. Accordingly, a new approach to out-of-hospital cardiac arrest called cardiocerebral resuscitation (CCR) was developed that places more emphasis on chest compressions for witnessed cardiac arrest in adults and de-emphasizes ventilation. There is also emphasis on chest compressions before defibrillation in circulatory phase of cardiac arrest. CCR was initiated in Tucson, Arizona, in November 2003, and in two rural Wisconsin counties in early 2004.

Cardiopulmonary Resuscitation↗
PubMed2006

Cardiocerebral resuscitation improves survival of patients with out-of-hospital cardiac arrest.

PURPOSE: The guidelines for cardiopulmonary resuscitation (CPR) have been in place for decades; but despite their international scope and periodic updates, there has been little improvement in survival rates in out-of-hospital cardiac arrest for patients who did not receive early defibrillation. The Emergency Medical Service directors in 2 rural Wisconsin counties initiated a new protocol for the pre-hospital management of adult cardiac arrest victims in an attempt to improve survival rates. The results observed after implementation of this protocol are presented and compared with those observed during a three-year period that preceded initiation of the project. METHODS: The protocol, based upon the principles of cardiocerebral resuscitation, was significantly different from the standard CPR protocol. A major objective was to minimize interruptions of chest compressions. Each defibrillation, including the first, was preceded by 200 uninterrupted chest compressions. Single shocks, rather than stacked shocks, were utilized. Post shock rhythm and pulse checks were eliminated, and chest compressions were resumed immediately after a shock was delivered. Initial airway management was limited to an oral pharyngeal device and supplemental oxygen. If the arrest was witnessed, assisted ventilations and intubation were delayed until either a return of spontaneous circulation or until three series of "compressions + analysis +/- shock" were completed. RESULTS: In the 3 years preceding the change in protocol, where standard CPR was utilized, there were 92 witnessed out-of-hospital adult cardiac arrests with an initially shockable rhythm. Eighteen patients survived, and 14 of 92 (15%) were neurologically intact. After implementing the new protocol in early 2004, there were 33 witnessed out-of-hospital adult cardiac arrests with an initially shockable rhythm. Nineteen survived, and 16 of 33 (48%) were neurologically normal. Differences in both total and neurologically normal survival are significant (chi-squared = 0.001). CONCLUSION: Instituting the new cardiocerebral resuscitation protocol for managing prehospital cardiac arrest improved survival of adult patients with witnessed cardiac arrest and an initially shockable rhythm.

Adult↗
PubMed2006

Rescuer fatigue: standard versus continuous chest-compression cardiopulmonary resuscitation.

OBJECTIVES: Continuous chest-compression cardiopulmonary resuscitation (CCC-CPR) has been advocated as an alternative to standard CPR (STD-CPR). Studies have shown that CCC-CPR delivers substantially more chest compressions per minute and is easier to remember and perform than STD-CPR. One concern regarding CCC-CPR is that the rescuer may fatigue and be unable to maintain adequate compression rate or depth throughout an average emergency medical services response time. The specific aim of this study was to compare the effects of fatigue on the performance of CCC-CPR and STD-CPR on a manikin model. METHODS: This was a prospective, randomized crossover study involving 53 medical students performing CCC-CPR and STD-CPR on a manikin model. Students were randomized to their initial CPR group and then performed the other type of CPR after a period of at least two days. Students were evaluated on their performance of 9 minutes of CPR for each method. The primary endpoint was the number of adequate chest compressions (at least 38 mm of compression depth) delivered per minute during each of the 9 minutes. The secondary endpoints were total compressions, compression rate, and the number of breaks taken for rest. The students' performance was evaluated on the basis of Skillreporter Resusci Anne (Laerdal, Wappingers Falls, NY) recordings. Primary and secondary endpoints were analyzed by using the generalized linear mixed model for counting data. RESULTS: In the first 2 minutes, participants delivered significantly more adequate compressions per minute with CCC-CPR than STD-CPR, (47 vs. 32, p = 0.004 in the 1st minute and 39 vs. 29, p = 0.04 in the 2nd minute). For minutes 3 through 9, the differences in number of adequate compressions between groups were not significant. Evaluating the 9 minutes of CPR as a whole, there were significantly more adequate compressions in CCC-CPR vs. STD-CPR (p = 0.0003). Although the number of adequate compressions per minute declined over time in both groups, the rate of decline was significantly greater in CCC-CPR compared with STD-CPR (p = 0.0003). The mean number of total compressions delivered in the first minute was significantly greater with CCC-CPR than STD-CPR (105 per minute vs. 58 per minute, p < 0.001) and did not change over 9 minutes in either group. There were no differences in compression rates or number of breaks between groups. CONCLUSIONS: CCC-CPR resulted in more adequate compressions per minute than STD-CPR for the first 2 minutes of CPR. However, the difference diminished after 3 minutes, presumably as a result of greater rescuer fatigue with CCC-CPR. Overall, CCC-CPR resulted in more total compressions per minute than STD-CPR during the entire 9 minutes of resuscitation.

Adult↗
PubMed2005

Interruptions of chest compressions during emergency medical systems resuscitation.

BACKGROUND: Survival after nontraumatic out-of-hospital (OOH) cardiac arrest in Tucson, Arizona, has been flat at 6% (121/2177) for the decade 1992 to 2001. We hypothesized that interruptions of chest compressions occur commonly and for substantial periods during treatment of OOH cardiac arrest and could be contributing to the lack of improvement in resuscitation outcome. METHODS AND RESULTS: Sixty-one adult OOH cardiac arrest patients treated by automated external defibrillator (AED)-equipped Tucson Fire Department first responders from November 2001 through November 2002 were retrospectively reviewed. Reviews were performed according to the code arrest record and verified with the AED printout. Validation of the methodology for determining the performance of chest compressions was done post hoc. The median time from "9-1-1" call receipt to arrival at the patient's side was 6 minutes, 27 seconds (interquartile range [IQR, 25% to 75%], 5 minutes, 24 seconds, to 7 minutes, 34 seconds). An additional 54 seconds (IQR, 38 to 74 seconds) was noted between arrival and the first defibrillation attempt. Initial defibrillation shocks never restored a perfusing rhythm (0/21). Chest compressions were performed only 43% of the time during the resuscitation effort. Although attempting to follow the 2000 guidelines for cardiopulmonary resuscitation, chest compressions were delayed or interrupted repeatedly throughout the resuscitation effort. Survival to hospital discharge was 7%, not different from that of our historical control (4/61 versus 121/2177; P=0.74). CONCLUSIONS: Frequent interruption of chest compressions results in no circulatory support during more than half of resuscitation efforts. Such interruptions could be a major contributing factor to the continued poor outcome seen with OOH cardiac arrest.

Adult↗
PubMed2005

Magnetic resonance imaging during untreated ventricular fibrillation reveals prompt right ventricular overdistention without left ventricular volume loss.

BACKGROUND: Most out-of-hospital ventricular fibrillation (VF) is prolonged (>5 minutes), and defibrillation from prolonged VF typically results in asystole or pulseless electrical activity. Recent visual epicardial observations in an open-chest, open-pericardium model of swine VF indicate that blood flows from the high-pressure arterial system to the lower-pressure venous system during untreated VF, thereby overdistending the right ventricle and apparently decreasing left ventricular size. Therefore, inadequate left ventricular stroke volume after defibrillation from prolonged VF has been postulated as a major contributor to the development of pulseless rhythms. METHODS AND RESULTS: Ventricular dimensions were determined by MRI for 30 minutes of untreated VF in a closed-chest, closed-pericardium model in 6 swine. Within 1 minute of untreated VF, mean right ventricular volume increased by 29% but did not increase thereafter. During the first 5 minutes of untreated VF, mean left ventricular volume increased by 34%. Between 20 and 30 minutes of VF, stone heart occurred as manifested by dramatic thickening of the myocardium and concomitant substantial decreases in left ventricular volume. CONCLUSIONS: In this closed-chest swine model of VF, substantial right ventricular volume changes occurred early and did not result in smaller left ventricular volumes. The changes in ventricular volumes before the late development of stone heart do not explain why defibrillation from brief duration VF (<5 minutes) typically results in a pulsatile rhythm with return of spontaneous circulation, whereas defibrillation from prolonged VF (5 to 15 minutes) does not.

Animals↗
PubMed2005

Effects of intravenous arginine vasopressin on epicardial coronary artery cross sectional area in a swine resuscitation model.

Although arginine vasopressin (AVP) has been shown to be a promising drug during cardiopulmonary resuscitation (CPR), concern has been raised about the potential for AVP-mediated vasoconstriction of the coronary arteries. In a prospective, randomized laboratory investigation employing an established porcine model, the effects of AVP on haemodynamic variables, left anterior descending (LAD) coronary artery cross sectional area employing intravascular ultrasound (IVUS), and return of spontaneous circulation were studied. During sinus rhythm, the LAD coronary artery cross sectional area was measured by IVUS at baseline, and 90 s and 5 min after AVP (0.4 U/kg IV). Following a 60 min recovery, ventricular fibrillation was induced. At 4 min, chest compressions were initiated; AVP (0.4 U/kg IV) was injected at 5.5 min, and defibrillation performed at 8 min. LAD coronary artery cross sectional area was measured by IVUS at the pre-arrest baseline, 90 s after drug injection during CPR, and 5 min after return of spontaneous circulation. Compared with baseline, the mid-LAD coronary artery cross sectional area increased significantly (P<.05) 90 s and 5 min after AVP administration (9.2+/-.5mm2 versus 10.7+/-.6mm2 versus 11.7+/-.6mm2, respectively) during normal sinus rhythm. Similarly during ventricular fibrillation and CPR plus AVP, the mid-LAD coronary artery cross sectional area increased at 90 s after AVP compared with baseline (9.5+/-.6mm2 versus 11.0+/-.7mm2; P<.05). Moreover, the cross sectional area increased further 5 min after return of spontaneous circulation (9.5+/-.6mm2 versus 14.0+/-.8mm2, P<.05). In conclusion, in this experimental model with normal coronary arteries, AVP resulted in significantly increased LAD coronary artery cross sectional area during normal sinus rhythm, during ventricular fibrillation with CPR, and after return of spontaneous circulation.

Anatomy, Cross-Sectional↗
PubMed2005

An alternative approach to advancing resuscitation science.

Stagnant survival rates in out-of-hospital cardiac arrest remain a great impetus for advancing resuscitation science. International resuscitation guidelines, with all their advantages for standardizing resuscitation therapeutic protocols, can be difficult to change. A formalized evidence-based process has been adopted by the International Liason Committee on Resuscitation (ILCOR) in formulating such guidelines. Currently, randomized clinical trials are considered optimal evidence, and very few major changes in the Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care are made without such. An alternative approach is to allow externally controlled clinical trials more weight in Guideline formulation and resuscitation protocol adoption. In Tucson, Arizona (USA), the Fire Department cardiac arrest database has revealed a number of resuscitation issues. These include a poor bystander CPR rate, a lack of response to initial defibrillation after prolonged ventricular fibrillation, and substantial time without chest compressions during the resuscitation effort. A local change in our previous resuscitation protocols had been instituted based upon this historical database information.

Cardiopulmonary Resuscitation↗