Acetylene Method Research Articles

Cardiac Output in the Pick Syndrome

The cardiac output of patients with the Pick syndrome was determined by means of the Grollman indirect acetylene method. This procedure is applicable to such patients in spite of their reduced vital capacity if the volume of the gas mixture to be re-breathed is decreased and if the rebreathing period is slightly increased. The cardiac output per minute per square meter of body surface Grollman calls the cardiac index. He has found that under basal conditions the normal person has a cardiac index of 2.2 ± 0.3 liters per minute. Any deviation of the index from the normal 2.2 greater than 15%, when determined by the acetylene method, is considered pathological. Mrs. S., age 54 years, with Pick's disease, who should have had an output of 3.50 liters per minute (calculated by multiplying the patient's surface area by 2.2), had an average output of 2.26 liters per minute, 36% below normal. The estimated normal output per beat is 47 cc; she had an average beat output of 20 cc, her heart rate being 114 per minute. Mrs. M., age 32 years, was operated on for the Pick syndrome. Her output normally should have been 3.04 liters per minute. Before operation she had an average minute output of 1.79 liters, 41% below normal. The tests after operation were carried out over a 2 weeks'period starting a month and a half after operation. Although there was not a striking increase in the average minute output of 1.84 liters (39% below normal), 5 of the 12 tests after operation reached a value never attained before operation. An average of the best 6 tests after operation gives an output of 2.05 liters per minute, only 33% below normal. This tendency toward improvement indicates that her heart has a reserve power and leads to the belief that as time goes on this patient's output will continue to improve. Before operation her beat output averaged 24 cc, her average heart rate being 75 per minute. After operation her beat output averaged 26 cc, the average heart rate being 71 per minute.

The Circulation in Anaemic Conditions

Using Grollman's acetylene method 17 circulation determinations were made in two patients, one suffering from pernicious anaemia and the other from haemolytic jaundice. With the lowest haemoglobin values both patients showed an increase in the minute-volume and systolic output as well as in the utilisation coefficient. The maximal rise in the minute-volume amounted to roughly 130 % (7.4 litres). During the convalescence of the patients no essential difference in the reaction, which consisted of a diminution in minute-volume and utilisation coefficient, was observed in the two anaemic types. The patient suffering from pernicious anaemia was observed during a remission produced by »ventriculin». During the remission the systolic output dropped by about 50%, and a close connection between the oxygen capacity of the blood and the arterio-venous oxygen difference was demonstrated. The increased utilisation coefficient, which was found chiefly with the lowest haemoglobin values, must be regarded as an economic provision which lessens the work of the heart. But at the same time it implies an encroachment on the reserves of the organism, which must be felt during muscular exertion.

An inquiry into the basis of the acetylene method of determining the cardiac output: Hamilton, W. F., Spradlin, M. C., and Saam, H. G.: Am. J. Physiol. 100: 587, 1932

An inquiry into the basis of the acetylene method of determining the cardiac output: Hamilton, W. F., Spradlin, M. C., and Saam, H. G.: Am. J. Physiol. 100: 587, 1932

Effect of Giving Digitalis on the Volume Output of the Heart and its Size in Heart Failure

It appears to be a fact that the giving of digitalis decreases the cardiac output (Burwell, Neighbors and Regen, and Stewart) and cardiac size (Stewart) in normal human beings. The effect of its administration when hearts are diseased is, however, still unknown, With the introduction by Grollman, of the acetylene method for measuring the cardiac output in man, a method became available for studying this condition. In this investigation the method of Grollman has been used. In addition to estimations of the cardiac output, the size of the heart was measured from x-ray photographs taken at a distance of 2 meters. In addition to the usual hospital records, electrocardiograms were made and the heart rate counted. Blood pressure and vital capacity were also investigated, but not reported here. All observations were made with patients in a basal metabolic state, immediately before digitalis was given and at frequent intervals afterward. The first patient, a male, 47 years of age, suffered from a first attack of heart failure. The records secured in studying his case illustrate the course of events in cases forming the group exhibiting normal cardiac mechanism and heart failure of the congestive type. The diagnosis was generalized arteriosclerosis, hypertension, rheumatic heart disease (mitral insufficiency), cardiac hypertrophy. His heart and liver were large. Ascites and edema of the lower extremities were present. The lungs were free of rales. During heart failure the cardiac output measured 2.88 liters per minute, i. e., it was diminished, and the heart now 198.3 sq. cm. in area was larger than during the stage of compensation. On the first occasion that digitalis was given, diuresis occurred and the patient became free of the signs and symptoms of heart failure.