INFLUENCE OF IRON PREPARATIONS ON OCCULT BLOOD TESTS

Ferrous fumarate (Fersamal) and ferrous carbonate (Ferrodic) may produce false-positive results with the orthotolidine tablet tests (Occultest and Hematest) if administered to patients being investigated for alimentary bleeding. Misleading results are also likely if the benzidine test is employed as a filter-paper procedure. Ferrous sulphate, gluconate, succinate, iron and ammonium citrate, and other preparations of iron have no influence on the modern tablet tests for occult alimentary bleeding.

ACETOACETATE TURNOVER AND OXIDATION RATES IN OVINE PREGNANCY KETOSIS

Labeled acetoacetic acid (AcAc) was administered as a tracer dose and as a continuous infusion to 24 twin-pregnant ewes with varying degrees of spontaneous or fasting hypoglycemic ketosis. The mean AcAc turnover rate of five normal twin-pregnant sheep (plasma AcAc < 1 mg/100 ml) was only 0.04 g/hr kg3/4 or 1.0 g/sheep hr. During ketosis the turnover rate of AcAc was directly proportional to the plasma AcAc concentration until a maximal concentration of about 10 mg/100 ml was attained (total ketone bodies, expressed as acetone, would be about 20 mg/100 ml). At higher plasma concentrations, the AcAc turnover rates remained constant at nearly 0.4 g/hr kg3/4 (9 g/sheep hr). About one-half of this AcAc was oxidized to CO2 regardless of the actual amount utilized. The mean percentage of the total exhaled CO2 derived from AcAc metabolism increased from 2% in normal ewes to a maximum of about 20% during pregnancy ketosis. Comparisons of these data to values obtained in previous experiments on artificially ketotic nonpregnant sheep indicate that an overproduction of ketone bodies, rather than an underutilization, is the major cause of ruminant ketosis.

CHANGES IN SERUM AND URINARY POTASSIUM LEVELS DURING PROFOUND HYPOTHERMIA IN MAN

Samples of blood were taken at five to 10-minute intervals during cooling, circulatory arrest, and rewarming in eight consecutive patients undergoing open cardiac surgery under profound hypothermia at nasopharyngeal and oesophageal temperatures of approximately 10 degrees C. and the serum potassium levels were estimated. Urine samples were also collected from six of the eight patients and the total potassium excretion calculated per minute. It was found that there was a tendency for the serum potassium level to rise towards the end of cooling. A further more significant rise occurred during circulatory arrest, and on rewarming there was a pronounced fall of approximately 2.5 mEq./litre, the lowest level being reached at 27.5 degrees C. Above 27.5 degrees C. there was no further significant change in the serum potassium level. It is suggested that the acidosis which occurs during circulatory arrest and a depression in the function of the cell membrane at very low temperatures are at least partly responsible for the changes in serum potassium. Certainly the excretion of potassium in the urine does not account for them.

SEROMUCOID IN LUPUS ERYTHRMATOSUS AND SCLERODERMA

Seromucoid levels in blood of 50 normal men and in 63 cases of cutaneous collagen diseases were studied. There was a marked rise in the seromucoid level in cases of systemic lupus erythematosus and also a significant rise in scleroderma. This rise in seromucoid level may be a reflection of the degenerative connective tissue.