Effects of transthoracic impedance and peak current flow on defibrillation success in a prehospital setting.

Study Objective: To assess whether transthoracic impedance and peak current are determinants of defibrillation success in patients with out-of-hospital ventricular fibrillation (VF).

Methods: A retrospective cohort study was carried out in a suburban Canadian EMS system. Participants were patients who experienced out-of-hospital cardiac arrest in the regional municipality of Ottawa-Carleton, had VF rhythm at presentation, and received countershocks from the Laerdal Heartstart 2000 automated external defibrillator.

Variation between femurs as measured by dual energy X-ray absorptiometry (DEXA).

It is commonly assumed that there is minimal variation between the hips in an individual, but is densitometry of one femur representative of the other? We performed bone mineral density (BMD) measurements of both hips using a Hologic QDR 1000 densitometer. There were 110 patients, all of whom were right handed, and three main groups of subjects: (1) normal volunteers (n = 36); (2) subjects with known hip pathology (n = 36); (3) subjects with medical conditions not affecting the hip (n = 38). The mean age of the subjects was 46 (21-87) years and a standard analysis protocol was followed in all patients.

The range of bone density in normal British women.

A study to determine the range of bone density in British females was carried out on a group of 165 normal women. The results showed an increase in mineral content with peak values occurring in the fourth decade (mean 1.06 g/cm2; 95% confidence limits 0.

Ventilator-dependent children.

The issue of the ventilator-dependent child is a relatively-new one in Australia. Ventilator-dependent children pose complex and unique ethical, medical, economic and psychological problems. The experience of two Australian centres that are involved with the care of ventilator-dependent children is reported.