John Tuckman

Clinical Evaluation of Diazoxide A New Treatment for Acute Hypertension

Forty-six hypertensive patients have received diazoxide intravenously. Three hundredmilligrams (one ampule) administered rapidly undiluted resulted in a 27 per cent average reduction in mean arterial pressure in 1 to 2 minutes. During the next 3 to 5 minutes the arterial pressure increased gradually to a 15 per cent average reduction as compared to the control. The average duration of diazoxide in these patients was 4.7 ± 1.7 hours. No signs of postural hypotension, cerebral ischemia, or collapse were noted. At the peak of hypotensive action there was a 41 per cent average reduction in total peripheral resistance.Repeated doses of diazoxide in both nonpregnant patients with acute hypertension and pregnant patients with toxemia adequately controlled the arterial pressure and were not associatetd with the development of drug resistance. The standard dosage of 300 mg. (one ampule), the immediate onset of action and the moderately long duration of action, the maintenance of cardiac output, the lack of significant side effects, and the fact that it can be administered repeatedly without the development of drug resistance make diazoxide administered intravenously the ideal therapy for acute hypertension.

Evaluation of the Pressor, Cardiac, and Renal Hemodynamic Properties of Angiotensin II in Man

These data demonstrate that in normal subjects angiotensin II is 10 times as potent as norepinephrine, which it resembles hemodynamically. An increase in the systolic pressure is associated with significant increase in diastolic pressure, increase in venous pressure, decrease in heart rate, slight decrease in cardiac output with striking increase in total peripheral resistance, decrease in renal blood flow, decreased glomerular filtration rate, increase in filtration fraction, arid slight decrease in urinary volume. Preliminary studies of patients in shock suggest that angiotensin II is two or three times as potent as norepinephrine. Continuous administration is not associated with the development of resistance or tachyphylaxis, nor does sloughing of tissues occur when there is leakage outside the vein.

Cardiac Index during Intravenous Levarterenol Infusion in Man

Cardiac indices were determined by the Stewart-Hamilton indicator-dilution method during intravenous infusions of levarterenol in 25 human subjects. The rate and duration of the infusion as well as the increase in arterial pressure and bradycardia were varied in order to study their influences on the cardiac index.

Evaluation of Chlorothiazide Alone in the Treatment of Moderately Severe and Severe Hypertension

The effectiveness of alternate 6-month courses of chlorothiazide alone with standard antihypertensive therapy is compared in 11 patients with severe hypertension and 30 patients with moderately severe hypertension. These results are then compared with those of a 6-month combined treatment period when the patients received both chlorothiazide and standard antihypertensive therapy.

Changes in Heart Rate During Levarterenol Infusion

Studies in this laboratory have demonstrated varying responses in heart rate during levarterenol-induced hypertension. A decreased bradycrotic response did not seem to depend on the age of the patient, the control level of arterial pressure or the percentage increase in mean arterial pressure. The present study was designed to evaluate the factors which govern the changes in heart rate during levarterenol infusion.

THE SIGNIFICANCE OF LATERAL AND GENERALIZED RETINAL SHEEN

Excerpt Previous publications from this clinic have described a wet, glistening appearance of the entire retina that is frequently associated with toxemia of pregnancy and glomerulonephritis.1, 2Si...

Dilution Curves of Simultaneously Administered 1131-Human Serum Albumin and Cr51-Labeled Erythrocytes in Patients with Various Types of Edema

Detailed indicator-dilution curves of simul taneously administered 1131-HSA and Cr51-RBC in six of eight edematous patients with congestive heart failure demonstrate that, as in normal patients, a significant quantity of 1 does not escape the intravascular space during the first several minutes post injection. It would seem, therefore, that cap illary permeability to albumin was not an im portant manifestation in these patients. De tailed indicator-dilution curves in five of six patients with edema not associated with con gestive heart failure differ from those derived from normal patients and from the edematous patients with congestive heart failure. These data do not exclude the possibility that capillary permeability to albumin might be a sig nificant concomitant of edema associated with chronic glomerulonephritis, disseminated lupus erythematosis, toxemia of pregnancy. car cinomatosis, and Kimmelstiel-Wilson syndrome.