Impact of a mobile coronary care unit on the sudden coronary mortality in a community

Sudden cardiac arrest outside the hospital--value of defibrillators in ambulances

In a region with a population of 250,000 people, all emergency calls for cardiac arrest were prospectively registered during a period of 6 years. Timing of events were carefully registered as were treatment and the participation of 3 ambulances equipped with defibrillators. When time until initial treatment of cardiac arrest was below 5 min, 12% could be resuscitated and discharged alive. This figure decreased to 2% in the period between 5 and 10 min and was zero to above 10 min. Similarly, a reasonable 12% of patients experiencing ventricular fibrillation at a public place could be resuscitated and discharged alive whereas only 5% of ventricular fibrillation occurring at the patients home could be successfully resuscitated. Asystolia was rarely treated successfully. Faster treatment improved results much and 63% of patients having ventricular fibrillation in the emergency room left hospital alive. Results of cardioversion in ambulances did not depend on time from initiation of cardiac arrest, but all patients receiving cardioversion later than 10 min died without regaining consciousness. The results were compared with other more effective programs. The study region apparently had much fewer cardiac arrest than a similar region in Seattle, U.S.A. In those cases where treatment could be initiated within 5 min, results were comparable.

Effect of mobile paramedic units on outcome in patients with myocardial infarction

To investigate the effect of mobile paramedic units on outcome, we prospectively studied for two years all patients with myocardial infarction admitted to the LDS Hospital emergency department who sought aid prior to cardiac arrest. One hundred thirty-four patients who received prehospital care from a mobile paramedic unit were compared with 101 patients who selected another means of initial care. Mortality, occurrence of life-threatening arrhythmias, and change in Killip class at 24 and 48 hours were the outcome variables. Data analysis by multiple logistic regression revealed that outcome was not improved, but a 29-minute median delay in hospital arrival occurred in paramedic-treated patients. Defibrillation was the only beneficial treatment performed by paramedics that could be identified. Current mobile paramedic unit procedures may need to be streamlined to eliminate the delay in hospital arrival resulting from extensive prehospital care.

The problem of cardiac arrest in the community

Out-of-hospital cardiac arrests constitute 350,000 cases yearly in the United States and 60,000 in the United Kingdom. Prompt resuscitation (CPR) by lay persons and fast defibrillation by paramedics have had epidemiologic consequences on both sides of the Atlantic. In Seattle there are 20.6 and in Brighton 10.0 long-term life-saves yearly per 100,000 persons. In Piedmont Virginia, coronary deaths fell 16% for persons 30-69 years old and 25% for those of all ages; prehospital life-saves accounted for 23% and 8% of each respective reduction. Since CPR by lay persons now triples the long-term survival rate when coupled with prehospital defibrillation, favorable benefit-to-cost ratios can be effected by adding advanced life support and citizen CPR to an extant ambulance system. Meticulous direct and indirect medical control by the physician assures the highest quality of CPR and early cardiac care (ECC). Diagnostic procedures like electro-provocation identify high-risk patients. Changes of behavior and diet, new drugs, new operations, and external and implantable automated devices reduce sudden deaths. In the future, automated defibrillation by first responders and trained lay persons (including members of families of high-risk patients) should increase the number of early survivors who become candidates for long-term therapy with drugs, operations, and devices.

Resuscitation skills among the population

According to a postal survey, 49% of the population living in the Finnish Lapland county has been taught how to resuscitate, but only 19% of the whole population there thought they would be capable of resuscitating a patient. Even among those who had been properly instructed, only 33% thought they would be able to perform resuscitation. It thus seems that not enough teaching sessions have been arranged to teach resuscitation to the whole population. In addition, the teaching sessions arranged do not ensure an adequate resuscitation technique for those who have received instruction.