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G J Avery

Publications and source records attributed to G J Avery.

4 recordsLinked to original sources
PubMed1979

Pharmacologic antagonism of beta-adrenergic blockade in dogs. I. Hemodynamic effects of isoproterenol, dopamine, and epinephrine in acute propranolol administration.

Hemodynamic effects of isoproterenol, dopamine, and epinephrine were studied before and after acute beta-adrenergic blockade in 16 open-chest, anesthetized mongrel dogs. Beta blockade was induced with 1 mg. per kilogram of intravenous propranolol. Cardiac output measurements were obtained by thermal dilution, and pressure recordings were obtained in the right ventricle, pulmonary artery, left atrium, left ventricle, and aorta. Derived parameters included stroke volume, pulmonary and systemic vascular resistances, and peak left ventricular dP/dt. In the presence of propranolol, epinephrine became a lethal drug in large doses and did not increase cardiac output in standard doses. Dopamine, in 25 to 50 mcg. per kilogram per minute doses, increased arterial pressure and systemic resistance; cardiac output was diminished compared with dopamine, 10 mcg. per kilogram per minute, prior to propranolol, as a result of increased resistance and decreased LV contractility. Isoproterenol, 0.6 to 0.9 mcg. per kilogram per minute, 15 to 20 times standard dosages, had moderately positive inotropic effects and increased cardiac output. Left ventricular systolic pressure with isoproterenol after propranolol was reduced when compared with effects of smaller doses prior to propranolol. These observations suggest that none of the catecholamines studied would be optimal for circulatory support in heart failure in the presence of propranolol. The present results define a pharmacologic basis for design of appropriate drug combinations for circulatory support in beta-blocked animals.

Adrenergic beta-Antagonists↗
PubMed1977

The clinical value of pediatric herniography.

We review the herniography experience at a community hospital. Twenty-nine patients, aged 4 weeks to 6 years, were examined. Herniography was most often helpful (25 of 29 patients) in determining the need for exploration of the clinically normal side in the patient with a unilateral hernia. By herniography, patients with a right inguinal hernia were found to have a left sac in 47% of cases; whereas with a clinical left inguinal hernia, the incidence of right sacs was 67%. Herniography was also useful (four of 29 patients) as a diagnostic aid in children with a history of hernia but inconclusive physical findings. In all patients explored, the roentgenographic findings were confirmed at surgery.

Child↗