Unilateral Renal Hemodynamics and Characteristics of Dye-Dilution Curves in Patients with Essential Hypertension and Renal Disease

Abstract

SUMMARYTo gain information concerning cardiorenal hemodynamics in essential hypertension, renal vascular disease, and chronic glomerulonephritis, indocyanine green was used to determine renal blood flow (RBF), renal blood volume (RBV), mean transit time (MTT), appearance time (AT), buildup time (BT), and passage time (PT), in 83 kidneys of 47 hypertensive patients and eight volunteers. Cardiac output (CO) was concurrently measured. Dye, injected into the renal artery, while renal venous blood was drawn through a cuvette densitometer, gave a reproducible curve within 7.7% + 2% with multi-exponential washout. RBF (dye) agreed closely (dye/PAH ratio = 1.04) with para-aminohippurate (PAH) estimated renal blood flow in 18 kidneys. The RBF and RBV were significantly higher in patients with essential hypertension with high cardiac output than in those with normal cardiac output and were reduced significantly in patients with renal vascular diseases, although CO was the same. The contour of dye curves differed between the various diseases due to significant differences in BT and PT. AT and BT were significantly prolonged in patients with malignant hypertension, renal artery stenosis, and chronic glomerulonephritis. BT was significantly shorter in essential hypertensives than in nonnals. PT and MTT were significantly longer in malignant hypertensive, renal artery stenosis, and chronic glomerulonephritis groups. Passage time was significantly longer in glomerulonephritics than in nephrosclerotics. The procedure has value for the study of human renal circulation.

Renal Function in Borderline Hypertensive First-Degree Relatives of Essential Hypertensives

“…Furthermore, the observation that borderline hypertensives show a significantly higher renal plasma flow than normoten sives, both in the control period and during the sodium load, is in agreement with the results obtained by Bianchi et al [28] in nor motensive, first-degree relatives of hyperten sives, but it is in contrast with the decrease in renal plasma flow reported in established hy pertension [30]. Several investigators, work ing with different methods, have observed a significant increase in renal plasma flow in patients with borderline hypertension associ ated with either an increased [24][25][26][27][28][29][30][31] or a normal cardiac output [32], During infusion of inulin and PAH, bor derline hypertensives showed significantly higher values of natriuresis and sodium clear ance than normotensives. This observation is consistent with the data of Baldwin et al [7] obtained in established hypertensives by in fusing inulin and PAH in distilled water.…”

Renal Distribution Volumes of Indocyanine Green, [51Cr]EDTA, and 24Na in Man during Acute Renal Failure after Shock. IMPLICATIONS FOR THE PATHOGENESIS OF ANURIA

“…In previous studies we attempted to reduce the influence of the recirculating indicator on the surface calculation by drawing an oblique base line between the pre-and postinjection levels (6,12). Other investigators ignored the second wave and simply extrapolated the exponential downslope to 1% of the curve's peak height (23)(24)(25)(26). A better way is probably to subtract the recirculation wave recorded from the contralateral vein, which yields values that are between those from the two other methods.…”

Asymmetry of Renal Blood Flow in Patients With Moderate to Severe Hypertension

“…Inequality in perfusion between kidneys has been observed in only a few studies. Kioschos et al 12 determined selective renal blood flow by means of the dye dilution technique in 5 normotensive controls and 15 essential hypertensives, including 8 subjects who were suspected of having nephrosclerosis. In 6 of the 15 essential hypertensives, differences in flow between kidneys exceeded 25%, whereas asymmetry was not found in the normotensives.…”