CLINICAL APPRAISAL OF STOP FLOW METHOD

Abstract

In 1957 Malvin first described stop flow technique as one of investigative methods of renal physiology. Though many experimental information regarding this method appeared since then, there has been no description of stop flow pattern in human kidneys. The author applicated this technique in man and fundamental stop flow patterns of several substances in osmotic diuresis through intravenous loading of hypertonic glucose solution were investigated. Objects of the investigation were 12 cases, 7 males and 5 females.
They were divided into 2 groups: in Group 1, the investigation was done on 6 kidneys during the course of urological surgery, namely ureterolithomy or nephropexy under spinal anesthesia according to the original technique of Malvin and in Group 2 it was done on 6 kidneys, utilizing endoscopic insertion of ure teral bag catheter.
The results are as follows:
1) There was no significant difference of stop flow patterns between Group 1 and Group 2, except that urine flows in the former were less than in the latter.
2) The stop flow pattern of sodium resembled very much to that of chloride, showing uniform distal reabsorption.
3) Acidification of urine was done in the relatively narrow portion of the most distal tubuli.
4) Concentration of creatinine reached to the maximum at the distal portion, indicating an intensive water reabsorption.
5) The pattern of PAH showed its secretion in the proximal segment of the nephron.
6) The stop flow pattern of potassium did not show any definitive tendency, when the value was expressed by (u/pK)/(u/pCr.). Typical tubular secretion of potassium in the distal portion was verified only in 2 of 12 kidneys.
These findings did not much differ from the findings ascertained in dogs, except that the stop flow pattern of potassium showed no difinitive tendency of tubular secretion.
Posibility of clinical application of stop flow method was discussed.