Factors limiting surgery for essential hypertension

Factors limiting surgery for essential hypertension

SELECTED 839 ABSTRACTS In Case 4, the initial treatment with streptomycin was begun a short time after the organism had implanted itself upon the h...

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SELECTED

839

ABSTRACTS

In Case 4, the initial treatment with streptomycin was begun a short time after the organism had implanted itself upon the heart valves. A five-day intensive course, using a total of 20 Gm. of streptomycin, was sufficient to cause complete clinical remission for a period of three months, in spite of a relatively resistant organism. The authors believe this duplicates their experience with penicillin-treated cases in which they found that smaller doses over a longer period of time were more efficacious in producing permanent cures than massive doses over a short period of time. They believe that a permanent cure would have been effected had the initial streptomycin course of 4.0 Gm. per day been continued for four to five weeks. This patient was readmitted to the hospital three months after the apparent arrest of the infection. At the time, however, a total of 41 Gm. of streptomycin given over a period of one month had no effect on the clinical course: The blood cultures were persistently positive for enterococcus, the resistance being ten times that of the standard organism. At the time of this report this patient was still febrile. BELLET. Murray, Ann.

G. : The Pathophysiology Surg. 126523 (Oct.),

of the

Cause

of Death

From

Coronary

Thrombosis.

1947.

Murray exposed the hearts in a series of dogs and ligated the anterior descending branch of the left coronary artery. ObservBions were made of the area of myocardium supplied by that artery, the cardiac output, the blood pressure, the electrocardiogram, and pulse rate. In some experiments the ligature was removed after a few seconds. The author then carried out in twenty-five dogs a series of resections of the areas in which an infarct developed and obtained,excellent healing and good recovery in each animal. The heart functioned well and the animals remained well for from one to two years. Murray discusses the possible clinical application of this procedure in coronary thrombosis as it is seen in man. LORD. Heinbecker, P. : Factors 535 (Oct.), 1947.

Limiting

Surgery

for

Essential

Hypertension.

Ann.

Surg.

126:

As a result of observations made on patients with Cushing’s syndrome and studies made on experimental animals, Heinbecker presents an hypothesis of the underlying basis of essential “It is postulated that functional influences in the central nervous system, parhypertension. ticularly in the frontal lobes of the cerebral cortex, normally may depress the hypothalamic nuclei which control the secretion of the neural hypophysis . . . On depression of the functional activity of these nuclei there results a diminution in the secretion of the neural hypophysis. This, on the basis of the experimental evidence presented, can be assumed to result in a stimulation of the eosinophil cells of the glandular hypophysis, and these in turn stimulate the adrenal cortex to greater activity. The combined influence of the anterior pituitary hormone and of the adrenal cortical hormone is to effect a constriction of the efferent glomerular arterioles of the kidney and a release of renin. The combined action of all three hormones here, as in Cushing’s syndrome, is held responsible for the arteriolar narrowing and the development of diastolic hypertension.” The author believes that there must be an underlying YIr:oclth muscles uf the blood vessels IO the vasoronstricting or&r that diastolic hypertension may develop.

constitutional susceptibility action of the three humoral

The only role sympathectomy can play in relieving diastolic hypertension, according hypothesis, is the denervation of the adrenal glands, and hence, a lowering of the output phrine which in turn exerts an unfavorable influence on the excitability of the central system for influences which normally lead to a depression of the hypothalamus.

of the agents in to this of epinenervous

The extent of the sympathectomy necessary to accomplish denervation of the adrenals is limited to bilateral removal of the first and second lumbar ganglia and sectioning of the splanchnic nerves priov to their junction with the celiac ganglia. More extensive sympathectomies, in the author’s opinion, serve no useful purpose. LORD.