Article

Effects of compression depth and pre-shock pauses predict defibrillation failure during cardiac arrest

University of Chicago, Chicago, Illinois, United States
Resuscitation (Impact Factor: 3.96). 12/2006; 71(2):137-45. DOI: 10.1016/j.resuscitation.2006.04.008
Source: PubMed

ABSTRACT Cardiopulmonary resuscitation (CPR) and electrical defibrillation are the primary treatment options for ventricular fibrillation (VF). While recent studies have shown that providing CPR prior to defibrillation may improve outcomes, the effects of CPR quality remain unclear. Specifically, the clinical effects of compression depth and pauses in chest compression prior to defibrillation (pre-shock pauses) are unknown.
A prospective, multi-center, observational study of adult in-hospital and out-of-hospital cardiac resuscitations was conducted between March 2002 and December 2005. An investigational monitor/defibrillator equipped to measure compression characteristics during CPR was used.
Data were analyzed from 60 consecutive resuscitations in which a first shock was administered for VF. The primary outcome was first shock success defined as removal of VF for at least 5s following defibrillation. A logistic regression analysis demonstrated that successful defibrillation was associated with shorter pre-shock pauses (adjusted odds ratio 1.86 for every 5s decrease; 95% confidence interval 1.10-3.15) and higher mean compression depth during the 30s of CPR preceding the pre-shock pause (adjusted odds ratio 1.99 for every 5mm increase; 95% confidence interval 1.08-3.66).
The quality of CPR prior to defibrillation directly affects clinical outcomes. Specifically, longer pre-shock pauses and shallow chest compressions are associated with defibrillation failure. Strategies to correct these deficiencies should be developed and consideration should be made to replacing current-generation automated external defibrillators that require long pre-shock pauses for rhythm analysis.

0 Bookmarks
 · 
190 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In CPR, sufficient compression depth is essential. The American Heart Association ("at least 5cm", AHA-R) and the European Resuscitation Council ("at least 5cm, but not to exceed 6cm", ERC-R) recommendations differ, and both are hardly achieved. This study aims to investigate the effects of differing target depth instructions on compression depth performances of professional and lay-rescuers. 110 professional-rescuers and 110 lay-rescuers were randomized (1:1, 4 groups) to estimate the AHA-R or ERC-R on a paper sheet (given horizontal axis) using a pencil and to perform chest compressions according to AHA-R or ERC-R on a manikin. Distance estimation and compression depth were the outcome variables. Professional-rescuers estimated the distance according to AHA-R in 19/55 (34.5%) and to ERC-R in 20/55 (36.4%) cases (p=0.84). Professional-rescuers achieved correct compression depth according to AHA-R in 39/55 (70.9%) and to ERC-R in 36/55 (65.4%) cases (p=0.97). Lay-rescuers estimated the distance correctly according to AHA-R in 18/55 (32.7%) and to ERC-R in 20/55 (36.4%) cases (p=0.59). Lay-rescuers yielded correct compression depth according to AHA-R in 39/55 (70.9%) and to ERC-R in 26/55 (47.3%) cases (p=0.02). Professional and lay-rescuers have severe difficulties in correctly estimating distance on a sheet of paper. Professional-rescuers are able to yield AHA-R and ERC-R targets likewise. In lay-rescuers AHA-R was associated with significantly higher success rates. The inability to estimate distance could explain the failure to appropriately perform chest compressions. For teaching lay-rescuers, the AHA-R with no upper limit of compression depth might be preferable. Copyright © 2015. Published by Elsevier Ireland Ltd.
    Resuscitation 02/2015; 89. DOI:10.1016/j.resuscitation.2015.01.031 · 3.96 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Hintergrund Rasche Erste-Hilfe-Maßnahmen haben einen entscheidenden Effekt auf das Überleben eines Patienten mit einem Atem-Kreislauf-Stillstand. Ob eine Unterstützung mit akustischen Anweisungen die Qualität der Herz-Lungen-Wiederbelebung durch Ersthelfer steigert, ist nicht ausreichend untersucht. Material und Methoden 110 Probanden wurden mit der fiktiven Situation eines Atem-Kreislauf-Stillstandes konfrontiert. Die Probanden wurden in eine Testgruppe und eine Kontrollgruppe randomisiert. Die Probanden der Testgruppe erhielten zur Unterstützung einen Audioplayer mit Erste-Hilfe-Anweisungen für die kardiopulmonale Reanimation. Ergebnisse In beiden Gruppen lag die „hands-off time“ bei 59%. Die Bewusstseinskontrolle und das Freimachen der Atemwege erfolgte in der Testgruppe signifikant häufiger (93% vs. 33%, bzw. 44% vs. 15%), während der Hilferuf (53% vs. 55%), die Herzdruckmassage (100% vs. 100%) und die Beatmung (98% vs. 96%) in beiden Gruppen gleich häufig durchgeführt wurde. Der Beginn der ersten Herzdruckmassage erfolgte in der Kontrollgruppe signifikant früher (38 s vs. 67 s; p Schlussfolgerung Der Audioplayer führte zu keiner Verbesserung der Effektivität der Ersten-Hilfe-Maßnahmen bei einem Atem-Kreislauf-Stillstand.
    Notfall 06/2011; 15(5):405-409. DOI:10.1007/s10049-011-1490-4 · 0.32 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Background: Although many smartphone application (app) programs provide education and guidance for basic life support, they do not commonly provide feedback on the chest compression depth (CCD) and rate. The validation of its accuracy has not been reported to date. This study was a feasibility assessment of use of the smartphone as a CCD feedback device. In this study, we proposed the concept of a new real-time CCD estimation algorithm using a smartphone and evaluated the accuracy of the algorithm. Materials and Methods: Using the double integration of the acceleration signal, which was obtained from the accelerometer in the smartphone, we estimated the CCD in real time. Based on its periodicity, we removed the bias error from the accelerometer. To evaluate this instrument's accuracy, we used a potentiometer as the reference depth measurement. The evaluation experiments included three levels of CCD (insufficient, adequate, and excessive) and four types of grasping orientations with various compression directions. We used the difference between the reference measurement and the estimated depth as the error. The error was calculated for each compression. Results: When chest compressions were performed with adequate depth for the patient who was lying on a flat floor, the mean (standard deviation) of the errors was 1.43 (1.00) mm. When the patient was lying on an oblique floor, the mean (standard deviation) of the errors was 3.13 (1.88) mm. Conclusions: The error of the CCD estimation was tolerable for the algorithm to be used in the smartphone-based CCD feedback app to compress more than 51 mm, which is the 2010 American Heart Association guideline.
    Telemedicine and e-Health 11/2014; 21(1). DOI:10.1089/tmj.2014.0051 · 1.54 Impact Factor

Full-text (2 Sources)

Download
52 Downloads
Available from
May 20, 2014