Cardiac arrest victims were more likely to receive good-quality bystander-initiated cardiopulmonary resuscitation (CPR) if multiple people assisted, researchers found.
Among cases of out-of-hospital cardiac arrest, CPR quality was associated with multiple rescuers initiating bystander CPR (OR 2.8, 95% CI 1.5-5.6), being in a central or urban setting (OR 2.1, 95% CI 1.3-3.3), and receipt of bystander-initiated CPR (OR 2.7, 95% CI 1.1-7.3), as well as longer duration of resuscitation (OR 1.1, 95% CI 1.0-1.1), according to Hideo Inaba, MD, of the Kanazawa University Graduate School of Medicine in Japan, and colleagues.
Good-quality bystander CPR was less commonly performed by a family member (P=0.0001), by older bystanders (P=0.0005), and in home environments (P<0.0001), they wrote online in the journal Resuscitation.
However, neurologically favorable survival 1 year after the event did not differ significantly between those who received good-quality versus poor-quality resuscitation (2.7% versus 0%, P=0.14).
Experts in the field of emergency medicine have noted that the key to survival and positive neurological outcomes for those experiencing an out-of-hospital cardiac arrest is the initiation of bystander CPR. This CPR should be performed with chest compressions only,without mouth-to-mouth resuscitation.
However, the authors noted that survival among patients with out-of-hospital cardiac arrest remains low.
The Japanese study followed self-reported observational data from emergency medical technicians (EMTs) in Ishikawa prefecture who arrived on the scene at 553 out-of-hospital cardiac arrests. The EMTs requested that the bystander administering CPR continue resuscitating the patient after arrival and evaluated whether bystander-initiated CPR was of good or poor quality based on:
- Appropriate hand positions or finger positions for infants
- Compression rate of at least 100 per minute
- Compression depth of at least 2 inches or at least one third of the anterior-posterior diameter of the chest
The authors also gathered information on the region of the arrest, location, the patient's age and sex, witnesses to the event, etiology of the arrest, whether or not CPR was initiated by a bystander or with the instruction of emergency medical services dispatch, type of CPR initiated, training experience of the bystander, initial cardiac rhythm, estimated time of collapse, time-points initiation of CPR bystanders and EMTs, time from call to EMT to arrival, sustained return of spontaneous circulation, 1-month survival, 1-year survival, and 1-year favorable survival with neurologically favorable outcomes.
Neurologically favorable outcomes were categorized as scores of one or two on the Glasgow-Pittsburgh cerebral performance categories test.
Time to calling emergency services from arrest did not differ between groups, though time to arrest or recognition of arrest to initiation of CPR was significantly shorter among those who provided good-quality CPR (median 3 minutes versus 4 minutes, P=0.0052).
The authors noted that their findings related to setting of the arrest and related resuscitation may vary in other regions, as "previous studies from other countries suggest that regional variation in the quality of EMS systems, including differences in out-of-hospital cardiac arrest outcomes and bystander characteristics, may differ among countries," and that one of those prior studies had findings opposite of what was found in their research. "The reasons for this difference are unclear," they wrote.
They also noted that the study was limited by CPR quality measurement only after the arrival of EMTs and not in the time between dispatch and arrival, by lack of evaluation of bystander background or training history, by a self-reported and estimated time of arrest, and by a sample size not large enough to detect significance in differences in neurological outcomes.
SOURCE: Cole Petrochko, MedPage Today