Cardiac arrest in private locations: different strategies are needed to improve outcome.

BACKGROUND: A tremendous amount of public resources are focused on improving cardiac arrest (OHCA) survival in public places, yet most OHCAs occur in private residences. METHODS AND RESULTS: A prospective, observational study of patients transported to seven urban and suburban hospitals and the individuals who called 911 at the time of a cardiac arrest (bystander) was performed. Bystanders (N=543) were interviewed via telephone beginning 2 weeks after the incident to obtain data regarding patient and bystander demographics, including cardiopulmonary resuscitation (CPR) training. Of all arrests 80.2% were in homes. Patients who arrested in public places were significantly younger (63.2 vs. 67.2, P<0.02), more often had an initial rhythm of VF (63.0 vs. 37.7%, P<0.001), were seen or heard to have collapsed by a bystander (74.8 vs. 48.1%, P<0.001), received bystander CPR (60.2 vs. 28.6%, P<0.001), and survived to DC (17.5 vs. 5.5%, P<0.001). Patients who arrested at home were older and had an older bystander (55.4 vs. 41.3, P<0.001). The bystander was less likely to be CPR trained (65.0 vs. 47.4%, P<0.001), less likely to be trained within the last 5 years (49.2 vs. 17.9, P<0.001), and less likely to perform CPR if trained (64.2 vs. 30.0%, P<0.001). Collapse to shock intervals for public versus home VF patients were not different. CONCLUSIONS: Many important characteristics of cardiac arrest patients and the bystander differ in public versus private locations. Fundamentally different strategies are needed to improve survival from these events.

Prospective evaluation of two-dimensional transthoracic echocardiography in emergency department patients with suspected pulmonary embolism.

OBJECTIVE: To prospectively examine the diagnostic accuracy of two-dimensional transthoracic echocardiography (2-D echo) in emergency department (ED) patients being evaluated for acute pulmonary embolism (PE). METHODS: This was a 14-month prospective observational trial of a convenience sample of ED patients undergoing evaluation for suspected PE at a suburban teaching hospital. The 2-D echo was defined as positive if any two of the following were noted: right ventricular dilation, abnormal septal motion, loss of right ventricular contractility, elevated pulmonary artery or right ventricular pressures, moderate to severe tricuspid regurgitation, or visualization of a clot seen in the right ventricle or pulmonary artery. The patient was considered to have a PE if one of the following was positive: a pulmonary angiogram, contrast helical computed tomography, a magnetic resonance angiogram, a high-probability ventilation/perfusion (V/Q) scan without contradictory evidence, or an intermediate-probability V/Q scan with ultrasonic evidence of deep venous thrombosis. RESULTS: Of 225 cases identified, 39 met the defined criteria for PE (17%). A 2-D echo was performed on 124 patients (55%), of whom 27 (22%) had PE. In 20 patients the 2-D echo had at least two indicators of right ventricular strain; however, only 11 of these patients had confirmed pulmonary embolus. The 2-D echo had a sensitivity of 0.41 (95% CI = 0.32 to 0.49) and a specificity of 0.91 (95% CI = 0.86 to 0.96). The likelihood ratio positive was a moderately strong 4.4, with a weak likelihood ratio negative of 0.6. CONCLUSIONS: Bedside 2-D echo is not a sensitive test for the diagnosis of PE in ED patients. Positive findings moderately increase the suspicion for PE but are not diagnostic.