Bystander/first responder CPR: ten years experience in a paramedic system.

The effectiveness of bystander CPR recently has been challenged. We undertook a ten-year retrospective review of our prehospital experience with witnessed cardiorespiratory arrest to ascertain save rates in patients receiving and not receiving CPR before paramedic advanced life support (ALS). Traumatic and poisoning arrests and children less than 18 years old were excluded. A total of 1,905 patients presenting to a paramedic system from November 1, 1973, to October 31, 1983, were bystander-witnessed arrests and attempted paramedic resuscitations. Four hundred five paramedic-witnessed arrests were excluded. One hundred eighty-two of 1,248 (14.6%) who had CPR initiated before paramedic ALS arrival were saves, compared to 38 of 252 (15%) who had no CPR initiated until paramedic arrival (P = NS). A save was defined as a patient discharged from the hospital. The respective save rates for coarse ventricular fibrillation were 148 of 628 (23.6%) (CPR before paramedic arrival) vs 35 of 151 (CPR delayed until paramedic arrival) (23.2%); electromechanical dissociation (EMD), 11 of 209 (5.3%) vs 0 of 38; asystole, 19 of 401 (4.7%) vs 3 of 61 (4.9%); and ventricular tachycardia, four of ten (40%) vs 0 of two. In this prehospital system, bystander/first responder CPR was found not to improve hospital discharge rates except in patients with initially documented rhythm of EMD.

The effectiveness of calcium chloride in refractory electromechanical dissociation.

The effectiveness of calcium in electromechanical dissociation (EMD) has been challenged. Retrospective studies have been contradictory. To determine its effectiveness a prospective, randomized, blinded study comparing calcium chloride and saline in refractory EMD was carried out in the pre-hospital setting from October 1982 to October 1983. Only patients who had received epinephrine and bicarbonate and were refractory were entered in the study. All trauma and pediatric arrests were excluded. Ninety patients presented in refractory EMD. Overall, eight of 48 who received calcium were resuscitated successfully in the field; two of 42 who received saline were resuscitated successfully (P less than .07). A successful resuscitation was defined as the conveyance of a patient with a pulse and a rhythm to an emergency department. Patients were analyzed for age, sex, and witnessing of arrest. There was no statistical difference in demographic data. When the group of EMD patients was broken down into subgroups based on the width of QRS, it was noted that patients with a QRS width less than 0.12 did not respond to calcium, whereas the successfully resuscitated in the group with widened QRS or ischemic changes (N = 70) was eight of 39, compared with one of 31 not receiving calcium (P less than .028). Only one patient who was resuscitated successfully was discharged from the hospital alive. Calcium has been shown to be effective in the cardiac resuscitation of patients in refractory EMD. There may be a subset of patients with widened QRS complexes or ischemic changes who will benefit to a greater extent from the use of calcium chloride.

Lack of effectiveness of calcium chloride in refractory asystole.

The effectiveness of calcium chloride in asystole has been challenged; retrospective studies have not supported its use. We conducted a prospective, randomized, blinded study comparing the effectiveness of calcium chloride with saline in the prehospital paramedic setting. Seventy-three patients who had received epinephrine, bicarbonate, and atropine and were in refractory asystole were included in the study, which was conducted from October 1982 to October 1983. Traumatic and pediatric arrests were excluded. The successful resuscitation rate was three of 39 in the calcium group versus one of 34 in the saline group (P less than .37). A successful resuscitation was defined as the conveyance of a patient with a pulse and a rhythm to an emergency department. Groups were analyzed for sex, age, and witnessed arrests. There was no statistically significant difference between the groups. No patient who was resuscitated successfully in the field was discharged from the hospital alive. We conclude that calcium chloride is not of value in resuscitating patients from refractory asystole in the prehospital cardiac arrest setting.