Pulmonary blood flow profiles with reduced right ventricular function in lambs.

The determinants of right ventricular (RV) performance with damaged RV free wall, such as occurs with RV infarction, are still unclear. Using 20-MHz Doppler ultrasound equipment, we investigated the changes in pulmonary blood flow velocity profiles before and after ligation of the right coronary artery. RV dp/dt, stroke volume, RV stroke work, aortic pressure and cardiac output decreased and central venous pressure rose after the ligation.

Effects of two rescue doses of synthetic surfactant in 344 infants with respiratory distress syndrome weighing 750 to 1249 grams: a double-blind, placebo-controlled multicenter Canadian trial. Canadian Exosurf Neonatal Study Group.

In a multicenter, double-blind, placebo-controlled rescue trial conducted at 13 Canadian hospitals, two 5 ml/kg doses of a synthetic surfactant or air placebo were administered to 344 infants with birth weights of 750 to 1249 gm who had established respiratory distress syndrome and an arterial/alveolar oxygen tension ratio less than 0.22. The first dose was given between 2 and 24 hours of age, and the second dose was given 12 hours later to the infants remaining on mechanical ventilation.

Induction of right ventricular hypertrophy with obstructing balloon catheter. Nonsurgical ventricular preparation for the arterial switch operation in simple transposition.

Background: Recently, a successful result with a rapid two-stage arterial switch operation (ASO) was reported for patients with transposition of the great arteries (TGA) with low left ventricular pressure. In this procedure, the interval between pulmonary arterial banding and ASO was approximately 1 week. This successful result indicates the possibility of a nonsurgical ventricular preparation procedure using an obstructing balloon catheter prior to ASO.

Three-dimensional visualization of pulmonary blood flow velocity profiles in lambs.

For a better understanding of the characteristics of blood flow in the pulmonary artery, we constructed three-dimensional images of velocity profiles of blood flow in the pulmonary artery from pulsed Doppler ultrasound recordings in 14 lambs aged 28-40 days. In 8 lambs, pulmonary hypertension was created by the central venous injection of monocrotaline pyrrole. Six lambs served as unaltered controls.

Direct vascular connection between adrenal gland and kidney may play an important role in pathogenesis of hypertension.

A direct vascular connection between adrenal gland and kidney exists in various species. Thereby kidney function might be modified by the adrenal gland more precisely. In addition, the impact of adrenal hormones on the kidney function due to this circulatory 'by-pass' might be much stronger than judged from the relevant hormone concentrations in the circulating blood.

Hemodynamic effects of endothelin-1 in the newborn piglet: influence on pulmonary and systemic vascular resistance.

The aim of this study was to investigate the influence of endothelin-1 (ET-1) on the pulmonary and systemic circulations in newborn piglets. Twelve piglets (mean age of 6.8 days, range of 1-12 days) were anesthetized with chloralose-urethane and ventilated at FiO2 = 1.

Opposite excitatory and inhibitory effects of central administration of glucagon and of insulin upon the sympathetic cervical and adrenal nerve activities in the rat.

The central effects of pancreatic glucagon and insulin given intracerebroventriculary (i.c.v.

Centrally administered glucagon stimulates sympathetic nerve activity in rat.

The effect of pancreatic glucagon given intravenously, intracerebroventricularly and microinjected into the nucleus of the solitary tract on sympathetic activity in the cervical trunk and adrenal nerve was examined in rat. In each case glucagon caused a relatively long-lasting substantial increase in discharge of both nerves. This finding shows that glucagon can act centrally to stimulate sympathetic activity.