STUDIES ON RENAL FUNCTION TESTS
MAINLY ON THE TEST BY RENAL VEIN CATHETERIZATION
1968 Volume 59 Issue 8 Pages 715-735
Details
1968 Volume 59 Issue 8 Pages 715-735
The renal function test by renal vein catheterization has been performed through the median cubital vein. In order to simplify this method, the author inserted the catheter into the renal vein via femoral vein. In some patients, this catheterization was carried out in the combination with ureteral catheterization.
The subjects of this test were 42 patients (30 males and 12 females), visiting the Urological Clinic of Showa University for 3 years beginning 1964. The test was performed on 84 kidneys in these patients.
1) The extraction ratios of para-aminohippuric acid (PAH) and sodium thiosulfate (Thio).
i) The extraction ratio of PAH in 16 normally functioning kidneys was between 81.3 and 92.2%, averaging 86.7±3.50%.
ii) That of Thio ranged from 19.3 to 34.8%, averaging 25.1±2.67%.
iii) In tuberculous kidneys, the appearance of excretory pyelography has well coincided with the extraction ratio of PAH, revealing that excretion rate of contrast media decreased extremely when the PAH extraction ratio was lower than 40%.
iv) In the cases of renal damage due to obstructive uropathy, tubular function is considered to be impaired first while glomerular function is maintained until the late stage of the disease. The result of the authors study on the extraction ratios of PAH and Thio coincided with this fact.
v) In some cases of obstructive uropathy, the excretion of contrast media is not noted by excretory pyelography, when renal function is fairly well maintained. However, even in such cases, renal function was well revealed by the excretion ratios of PAH and Thio.
vi) Estimation of the extraction ratios of PAH and Thio proved to be useful in the discovery of diseases which are sometimes difficult to find by other laboratory examinations.
vii) The amounts of electrolytes and other substances in renal venous blood and arterial one were so different that the comparison of these values was considered useless.
2) The extraction ratios of PAH and Thio were compared with renal excretion of electrolytes. However, it has been shown that the estimation of electrolytes excretion from the kidney gives no imoortant information on renal function.
