PubMed Health⌕ Search

Biomedical subjects

R A Warner

Publications and source records attributed to R A Warner.

45 records · Page 3Linked to original sources
PubMed1979

Improvement in arterial oxygenation by saralasin infusion in man.

Simultaneous hemodynamic and blood gas measurements were performed in 26 hypertensive adults, who were cigarette smokers, before and after a 30-minute infusion of saralasin (5 microgram/kg/min) which is a highly specific competitive antagonist of angiotensin II (AII). The arterial pressure fell in nine, rose in seven and was unchanged in ten patients. The mean cardiac index for the entire group remained unchanged. Pulmonary arterial or wedge pressure, pulmonary vascular resistance, arterial PCO2 and pH did not change. Unrelated to the hemodynamic changes, the mean arterial oxygen pressure (PaO2) increased from 68.6 +/- 2.2 mm Hg to 73.9 +/- 2.1 mm Hg (P less than 0.001). In the absence of a significant increase in alveolar ventilation as indicated by an unchanged mean PCO2 and lacking a hemodynamic explanation, the mechanism for the rise in PaO2 is speculative at this stage. The possibility of an improvement in the distribution of ventilataion by saralasin infusion is under investigation.

Adult↗
PubMed1978

Effects of sublingual nitroglycerin on resting pulmonary gas exchange and hemodynamics in man.

Simultaneous hemodynamic, ventilation and blood gas measurements were performed in 19 males during cardiac catheterization for evaluation of chest pain syndrome before and 3 to 5 min after 0.4 mg sublingual nitroglycerin. Pulmonary arterial pressures and total pulmonary vascular resistance fell (P less than 0.001 for both), and mean systemic arterial pressure decreased (P less than 0.05). However, peripheral vascular resistance, cardiac output, and mixed venous PO2 did not change. Total and tidal ventilation, PCO2, pH, and base excess remained unchanged. However, the arterial PO2 decreased from a mean of 80 +/- 3 (SEM) to 72 +/- 2 mm Hg (P less than 0.001) and mean venous admixture increased from 8.8 +/- 1% to 12.6 +/- 1.5% (P less than 0.001). The alveolar arterial PO2 difference increased (P less than 0.001) and the dead space tidal volume ratio rose (P less than 0.05). We conclude that the decrease in arterial PO2 following sublingual nitroglycerin is caused by redistribution of pulmonary blood flow with imbalance in ventilation-perfusion relationships or shunting.

Adult↗
PubMed1977

Hemodynamic, ventilatory and blood gas changes during infusion of sodium nitroferricyanide (nitroprusside). Studies in patients with congestive heart failure.

Simultaneous hemodynamic, ventilatory, and blood gas studies were performed in 16 men with congestive heart failure before and during infusion of sodium nitroferricyanide (nitroprusside). The cardiac index increased from 2.00+/-0.16 L/min/sq m (SE) to 2.38+/-0.14 L/min/sq m, and the total pulmonary and systemic peripheral resistances fell from 928+/-123 to 494+/-57 dynes sec cm-5 and from 2,208+/-210 to 1,558+/-121 dynes sec cm-5, respectively. Both systemic and pulmonary arterial decreased during infusion of sodium nitroferricyanide, and the mixed venous oxygen pressure increased. There was no change in total or alveolar ventilation, arterial carbon dioxide tension, pH, or base excess; however, the mean arterial oxygen pressure (PaO2) decreased from 74+/-3 mm Hg to 68+/-3 mm Hg and the venous admixture effect increased from 8+/-1% to 13+/-2%. We conclude that the decrease in PaO2 during infusion of sodium nitroferricyanide resulted from a worsening of the ventilation-perfusion relationships due to increased perfusion of underventilated pulmonary units.

Adult↗
PubMed1977

Treatment of acute aortic insufficiency with sodium nitroferricyanide. Documentation of beneficial effect by noninvasive means.

The findings in a patient with acute aortic insufficiency who was treated with sodium nitroferricyanide (sodium nitroprusside) prior to aortic valve replacement are presented. Administration of the drug resulted in clinical improvement, which was reflected in changes in systemic and pulmonary arterial pressures and in noninvasive measurements. Sodium nitroferricyanide is useful in the management of patients with severe acute aortic insufficiency, and its effect may be monitored by noninvasive means.

Aortic Valve Insufficiency↗
PubMed1975

Deglutition.

Explore the source record for details and available documents.

Adolescent↗
PubMed1975

Deglutition.

Explore the source record for details and available documents.

Adolescent↗
PubMedDate not supplied

Effect of age on arterial distensibility in Asymptomatic humans.

This report describes a noninvasive method by which the volume distensibility of forearm arteries can be calculated from direct measurements of pulse wave velocity. Such measurements are made at a variety of transmural arterial pressures (TMP) accomplished by placing the forearm in a cylinder and changing the pressures within. This technique eliminates arterial blood pressure as a variable, which strongly influences arterial distensibility. We studied 48 asymptomatic men and women, ages 21 to 98 years. There was considerable scatter, but significant positive relationships were demonstrated between increasing arterial distensibility and age at ambient and lower TMPs. This finding can be explained by an age-related reduction in arterial luminal diameter and an increase in arterial wall thickness which reduces arterial wall tension and more than offsets the increased stiffness produced by changes in wall composition. In six subjects, pulse tracings were simultaneously recorded on paper and analog tape. The taped curves were digitized and subjected to Fourier analysis to determine the wave velocity of individual harmonics. The characteristic wave velocity was defined and found comparable to the hand method used in the same beats (regression coefficient = + 0.97). These data indicate that the automatic and manual methods measured the same variable.

Adult↗