title: Mechanical chest compression does not seem to improve outcome after out-of hospital cardiac arrest. A single center observational trial.
abstract: OBJECTIVE
  Recently three large post product placement studies, comparing mechanical chest compression (cc) devices to those who received manual cc, found equivalent outcome results for both groups. Thus the question arises whether those results could be replicated using the devices on a daily routine.
  
  
  METHODS
  We prospectively enrolled 948 patients over a 12 months period. Chi-Square test and Mann-Whitney-U test were used to assess differences between "manual" and "mechanical" cc subgroups. Uni- and multivariate Cox regression hazard analysis were used to assess the influence of cc type on survival.
  
  
  RESULTS
  A mechanical cc device was used in 30.1% (n=283) cases. Patients who received mechanical cc had a significantly worse neurological outcome - measured in cerebral performance category (CPC) - than the manual cc group (56.8% vs. 78.6%, p=0.009). Patients receiving mechanical cc were significantly younger, more were male and were more likely to have bystander CPR and an initially shock-able ECG rhythm. There was no difference in the quality of CPR that might explain the worse outcome in mechanical cc patients.
  
  
  CONCLUSIONS
  Even with high quality CPR in both, manual and mechanical cc groups, outcome in patients who received mechanical cc was significantly worse. The anticipated benefits of a higher compression ratio and a steadier compression depth of a mechanical cc device remain uncertain. In this study selection for mechanical cc was not standardized, and was non-random. This merits further investigation. Further research on how mechanical cc is chosen and used should be considered.
  
  
  BACKGROUND
  https://ekmeduniwien.at/core/catalog/2013/ (EK-Nr:1221/2013).
authors: Department of Emergency Medicine, Medical University of Vienna, Vienna, Austria.
authors: Sebastian
authors: S
authors: Zeiner
authors: Department of Emergency Medicine, Medical University of Vienna, Vienna, Austria.
authors: Patrick
authors: P
authors: Sulzgruber
authors: Department of Emergency Medicine, Medical University of Vienna, Vienna, Austria.
authors: Philip
authors: P
authors: Datler
authors: Department of Emergency Medicine, Medical University of Vienna, Vienna, Austria.
authors: Markus
authors: M
authors: Keferböck
authors: Department of Emergency Medicine, Medical University of Vienna, Vienna, Austria.
authors: Michael
authors: M
authors: Poppe
authors: Department of Emergency Medicine, Medical University of Vienna, Vienna, Austria.
authors: Elisabeth
authors: E
authors: Lobmeyr
authors: Department of Emergency Medicine, Medical University of Vienna, Vienna, Austria.
authors: Raphael
authors: R
authors: van Tulder
authors: Municipal Ambulance Service of Vienna, Vienna, Austria.
authors: Andreas
authors: A
authors: Zajicek
authors: Municipal Ambulance Service of Vienna, Vienna, Austria.
authors: Angelika
authors: A
authors: Buchinger
authors: Municipal Ambulance Service of Vienna, Vienna, Austria.
authors: Karl
authors: K
authors: Polz
authors: Municipal Ambulance Service of Vienna, Vienna, Austria.
authors: Georg
authors: G
authors: Schrattenbacher
authors: Department of Emergency Medicine, Medical University of Vienna, Vienna, Austria. Electronic address: fritz.sterz@meduniwien.ac.at.
authors: Fritz
authors: F
authors: Sterz
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001317:Austria / Q000453:epidemiology; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004562:Electrocardiography; D004632:Emergency Medical Services; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006336:Heart Massage / Q000295:instrumentation*; D006801:Humans; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D011312:Pressure; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate / Q000639:trends; D013909:Thorax; D013997:Time Factors; D016896:Treatment Outcome
keywords: Cardiopulmonary resuscitation; Mechanical chest compression; Mortality; Out-of-hospital cardiac arrest; Survival