- 作者：Trond Nordseth ; Dana Peres Edelson ; Daniel Bergum ; Theresa Mariero Olasveengen ; Trygve Eftest酶l ; Rune Wiseth ; Jan Terje Kval酶y ; Benjamin S. Abella ; Eirik Skogvoll
- 关键词：Cardiopulmonary resuscitation ; Cardiac arrest ; Dynamics
- 刊名：Resuscitation
- 出版年：January, 2014
- 年：2014
- 卷：85
- 期：1
- 页码：75-81
- 全文大小：1246 K
ss="h4">Background
In advanced life support (ALS), time-cycled 鈥渓oops鈥?of chest compressions form the basis of action. However, the provider must compromise between interrupting compressions and detecting a change in cardiac rhythm. An 鈥渙ptimal鈥?loop duration would best balance these choices. The current international CPR guidelines recommend 2-min loop durations. The aim of this study was to investigate the 鈥渙ptimal鈥?loop duration in patients with initial asystole or pulseless electrical activity (PEA).ss="h4">Materials and methods
Detailed defibrillator recordings from 249 in-hospital cardiac arrests at the University of Chicago Medicine (Chicago, IL) and St. Olav University Hospital (Trondheim, Norway) were analysed. The clinical states of asystole, PEA, ventricular fibrillation/-tachycardia (VF/VT) and return of spontaneous circulation (ROSC) were annotated along the time axis. PEA and asystole were combined as a single state for the analysis of state development. The probability of staying in PEA/asystole over time was estimated non-parametrically. In addition, to distinguish between initial and secondary PEA/asystole, the latter was defined by the transition from VF/VT or ROSC.
ss="h4">Results
Among patients with initial PEA (n = 179), 25% and 50% of patients had left PEA/asystole after 4 and 9 min of ALS efforts, respectively. The corresponding time points for patients with initial asystole (n = 70) were 7.3 and 13.3 min, respectively. The probability of transition from secondary PEA/asystole to ROSC or VF/VT varied between 10% and 20% in each 2-4 min interval.
ss="h4">Conclusion
The 鈥渙ptimal鈥?first loop duration may be 4 min in initial PEA and 6-8 min in initial asystole. If secondary PEA/asystole is encountered, 2-min loop duration seems appropriate.