Heart-to-heart talk. Roundtable discussion.

This past August the American Heart Association (AHA) released a major revision of its recommendations for emergency cardiovascular care (ECC). The 2000 guidelines simplify CPR techniques for the layperson and strongly promote the use of community early defibrillation. What repercussions can we expect from these changes? We asked five experts to join a roundtable discussion of the BLS aspects of these new guidelines. Their conversation follows.

The most important changes in the international ECC and CPR guidelines 2000.

Many people involved with resuscitation have specific interests and enthusiasm. They will review the new guidelines to see how their favorite interventions fared. This essay lists a number of the new guidelines that merit special attention: support for family presence at resuscitations, pronouncing death at the scene rather than after futile transport efforts, honoring advance directives, comparable effectiveness of bag-mask ventilation versus tracheal intubation, revision of compression rates and compression-ventilation ratios, and devices to confirm tracheal intubation and prevent tube dislodgment. Even more important are the new principles and concepts that the International Guidelines 2000 endorse: international guideline science, international guideline development, evidence-based guidelines, training by objectives, expanded scope of ECC to first aid and periarrest conditions, avoidance of false-negative (type II) errors, video-mediated instruction, and a philosophy to 'do no harm.' The number and magnitude of these new guidelines reflect the dynamic nature of resuscitation at the start of the 21st century. There is great optimism that these new and revised guidelines will help achieve our ultimate objective. This objective is to be ready when fate brings some lives to a premature end. If we are, we can restore more of these people to a high-quality life, ready for many more years of living.

Guidelines based on the principle 'First, do no harm'. New guidelines on tracheal tube confirmation and prevention of dislodgment.

In summary, this editorial and the one on pulse check point out another area in which a total reliance on evidence-based guidelines amy do our patients a disservice. The debate over dropping the pulse check hinged less on the strength of the evidence and more on the widespread clinical principle of fear of false-negative errors. The discussion of secondary confirmation of tracheal tube placement also lacks a strong base of evidence that identifies the one best technique of tube confirmation for patients with a pulse versus those without a pulse. The principles of the zero-risk intervention and first, do no harm come into play in this situation. We must deal with the growing awareness of the fact that tracheal intubation is not only a potentially lethal intervention but now is also a confirmed lethal intervention, and at a much higher death rate than has ever been suspected. Factors that contribute to the transformation of the tracheal tube from a life-saving to a death-causing intervention are being identified by honest and open researchers. National societies in emergency medicine are responding appropriately. We strongly recommend shifting from making an evidence-based recommendation to instead making a principle-based recommendation--killing our patients is unacceptable; we must act on the widespread concept regarding errors in medicine. We must adopt zero-risk interventions in all possible situations.

Amiodarone for resuscitation after out-of-hospital cardiac arrest due to ventricular fibrillation.

BACKGROUND: Whether antiarrhythmic drugs improve the rate of successful resuscitation after out-of-hospital cardiac arrest has not been determined in randomized clinical trials. METHODS: We conducted a randomized, double-blind, placebo-controlled study of intravenous amiodarone in patients with out-of-hospital cardiac arrest. Patients who had cardiac arrest with ventricular fibrillation (or pulseless ventricular tachycardia) and who had not been resuscitated after receiving three or more precordial shocks were randomly assigned to receive 300 mg of intravenous amiodarone (246 patients) or placebo (258 patients). RESULTS: The treatment groups had similar clinical profiles. There was no significant difference between the amiodarone and placebo groups in the duration of the resuscitation attempt (42+/-16.4 and 43+/-16.3 minutes, respectively), the number of shocks delivered (4+/-3 and 6+/-5), or the proportion of patients who required additional antiarrhythmic drugs after the administration of the study drug (66 percent and 73 percent). More patients in the amiodarone group than in the placebo group had hypotension (59 percent vs. 48 percent, P=0.04) or bradycardia (41 percent vs. 25 percent, P=0.004) after receiving the study drug. Recipients of amiodarone were more likely to survive to be admitted to the hospital (44 percent, vs. 34 percent of the placebo group; P=0.03). The benefit of amiodarone was consistent among all subgroups and at all times of drug administration. The adjusted odds ratio for survival to admission to the hospital in the amiodarone group as compared with the placebo group was 1.6 (95 percent confidence interval, 1.1 to 2.4; P=0.02). The trial did not have sufficient statistical power to detect differences in survival to hospital discharge, which differed only slightly between the two groups. CONCLUSIONS: In patients with out-of-hospital cardiac arrest due to refractory ventricular arrhythmias, treatment with amiodarone resulted in a higher rate of survival to hospital admission. Whether this benefit extends to survival to discharge from the hospital merits further investigation.

Automated external defibrillators: skill maintenance using computer-assisted learning.

OBJECTIVE: To determine whether computer-assisted learning (CAL) can maintain the automated external defibrillation (AED) skills of emergency medical technicians (EMTs). METHODS: The authors conducted a 1-year prospective comparison of an AED-skill training software program, running on desktop computers, with traditional instructor-led training. The subjects were experienced EMT-Ds (EMT-defibrillation), already trained in automated defibrillation (n = 105) employed as full-time professional EMT-D/firefighters. Two of the 3 groups (groups A and C) in the study were assigned to use the CAL program for 6 months. The third group (group B) remained on the normal, instructor-led training regimen. Pre- and poststudy skill levels were measured using a skills performance test. RESULTS: A secular trend of improved mean treatment scores was observed across all 3 groups [mean rise of 0.49 point (p = 0.01), repeated-measures analysis of variance]. There were no differences between training groups in the increase in performance scores (p = 0.3). The 1-time cost of supplying the CAL program to the 105 EMT-Ds was $1,575, significantly less than the $3,240-per-year cost associated with instructor-led training. CONCLUSIONS: The authors observed satisfactory AED skill maintenance for experienced EMT-Ds using CAL to replace 2 of 4 quarterly instructor-led skills reviews. CAL has cost and convenience advantages over instructor-based skill maintenance and is an acceptable alternative.

Human research on cardiopulmonary resuscitation: current constraints on implementation.

Researchers face a number of constraints to human resuscitation research. To overcome these constraints we must first recognize them and then work to develop solutions. The constraints include history, which tends to create a standard-of-care aura around practices that have not been confirmed by valid research. Until recently, we have lacked uniform models, nomenclature, and definitions for resuscitation research, though the "Utstein style" movement is doing much to overcome this particular constraint. We have to face several barriers that emerge from the very nature of human cardiopulmonary emergencies, such as its relative rarity, the multifactorial causes and outcomes, and its sudden, unpredictable nature. Good research requires appropriate levels of funding. Currently, human resuscitation research does not rank high on the funding priority list of our major funding agencies. This requires an organized approach to generate funding support and requires strong, coherent research proposals. Despite these constraints, we face many opportunities to improve survival from cardiopulmonary emergencies.