Computer algorithms that interpret prehospital ECGs often miss STEMI (ST-segment elevation myocardial infarction) and shouldn’t be used as the only means of prehospital activation of cardiac catheterization labs, finds a study by researchers at Summa Akron City Hospital, a Level 1 trauma center in Akron, Ohio.
A review of 200 prehospital ECGs (100 patients with STEMI and 100 controls) done using Lifepak 12 monitors and transmitted by one of more than 20 EMS agencies to the hospital’s ED found that the computer algorithm missed STEMI in 42 out of 100 patients. On the plus side, there were no false-positives for STEMI, meaning that the cath lab was never activated unnecessarily as a result of the computer interpretation. The researchers conclude that although prehospital computer ECG interpretation should not be used on its own to activate cath labs, computers “may serve as an adjunct to interpretation” by a paramedic or physician.
Limitations of the study include that it was relatively small and included only one brand of equipment, according to the researchers. The study was published online Oct. 15, 2012, in Prehospital Emergency Care.
Bystanders Less Likely to Do CPR in Black, Lower-Income Neighborhoods
Blacks in low-income neighborhoods are half as likely to receive bystander CPR than whites in high-income neighborhoods, researchers from the Colorado School of Medicine in Aurora report in the Oct. 25, 2012, issue of the New England Journal of Medicine. Researchers analyzed data from the Cardiac Arrest Registry to Enhance Survival on 14,225 patients in 29 U.S. cities who experienced an out-of-hospital cardiac arrest. Overall, nearly 29 percent received bystander CPR.
Compared with people who had a cardiac arrest in high-income white neighborhoods, cardiac arrest victims were:
- 23 percent less likely to receive CPR in high-income, predominantly black neighborhoods
- 35 percent less likely to receive CPR in poor, predominantly white neighborhoods
- 51 percent less likely to receive CPR in poor black neighborhoods
In addition, bystander CPR was twice as likely for a witnessed arrest than one that had no witnesses, and 70 percent more likely for an arrest that occurred in public. Researchers defined high income as neighborhoods with a median income of $40,000 or more; low income was below $40,000.
One in Four ED Visits ‘Potentially Preventable’
About 25 percent of all ED visits and initial hospital admissions are “potentially preventable,” according to a report from the independent Medicare Payment Advisory Commission (MedPAC) released Oct. 5, 2012. Preventable admissions were defined as those that could have been avoided with less-costly outpatient care; heart failure and upper-respiratory tract infection are the two most common reasons for these admissions.
MedPAC contracted with 3M Health Information Services to conduct a review of 5 percent of Medicare claims data from 2006 to 2008 across six regions of the United States.
Chillier Temps May Be Best After Cardiac Arrest
Therapeutic hypothermia that chills cardiac arrest patients to 32° C (89.6° F) may be more effective than chilling patients to 34° C (93.2° F), new research suggests.
Current guidelines call for cooling comatose out-of-hospital cardiac arrest patients to 32–34° C for 12 to 24 hours. But a study involving 36 patients in Spain who were randomized to be chilled to either 32° C or 34° C found that those who were cooled to the lower end of the range had better odds of surviving without severe neurological deficits (44 percent compared to 11 percent), although the difference didn’t reach statistical significance. However, when only patients with an initial shockable rhythm were included in the analysis, 62 percent of those cooled to 32° C survived, compared to 15 percent of those chilled to 34° C, which was statistically significant.
Researchers note that the study isn’t meant to change clinical practice, but to inform future research, including whether chilling to below 32° C would be better still. The study was published online Nov. 6, 2012, in Circulation.
Place Ribbon—and an AED—at Marathon Finish Lines
A review of cardiac arrests at 88 U.S. marathons finds that most occur after mile 15, particularly between mile 23 and the finish line.
Researchers from Crozer-Keystone Healthplex Sports Medicine Institute in Springfield, Pa., surveyed marathon medical directors nationwide and identified 30 cardiac arrests that occurred during marathons between 1976 and 2009. All but two of the arrests occurred in men, whose average age was 50. Ten died; 20 survived. An AED was used on 17 of the survivors and in three of the 10 deaths.
The overall risk of sudden cardiac arrest among marathoners was one in 57,000, while the risk of sudden cardiac death was one in 171,000. Sixteen of the cardiac arrests occurred between mile 23 and the finish line, suggesting that while AEDs should be placed all along the race route, they certainly should be near the finish line.
The study was presented in October 2012 at the annual meeting of the American Academy of Family Physicians in Philadelphia.
