renal blood flow

Renal blood flow refers to the blood flow through the kidneys per unit time. If a substance in the blood can be filtered by both the glomerulus and the renal tubules, the clearance rate is a combined result of glomerular filtration and tubular excretion. If the substance is completely removed after 1 week of renal circulation, the plasma clearance of the substance is equal to the plasma flow within 1 min of the kidney. The clearance rate of diodrast and para-aminohippurate (PAH) can reflect renal blood flow. Basic Information Specialist classification: urinary examination classification: urine / kidney function test Applicable gender: whether men and women apply fasting: fasting Tips: Please cooperate with the doctor's work when checking. Normal value 600-800ml/min. Clinical significance 1, RPF reduction, can be seen in (1) Chronic renal insufficiency or chronic pyelonephritis, the RPF is reduced due to renal vascular damage. (2) In the early stage of hypertension, the effective vascular bed is reduced due to vasospasm and renal arteriosclerosis. (3) When shock and cardiac dysfunction, RPF can be significantly reduced transiently. 2, RPF rises, can be seen in (1) In the early stage of acute glomerulonephritis, renal blood flow may be normal or elevated due to congestion. (2) Metabolic diseases such as acromegaly and giant disease RPF can be elevated. (3) RPF in pregnant women can also be elevated. Low results may be diseases: high results of chronic renal failure may be diseases: acute glomerulonephritis considerations Contraindications: 1. After urography or arteriography. 2. After applying diuretics, laxatives, and antihypertensive drugs. 3. When the body is dehydrated or edema. Inspection process (1) On the test day, the patient was placed on an empty stomach, and at 7 o'clock, 500 ml of water was given, and the catheter was indwelled. (2) Take 10 ml of urine at 7:30, and take 2 ml of venous blood (test blank). (3) Immediately, a sterile 200 g/LPAH solution was intravenously injected at 0.4 ml/kg body weight within 10 min, and then 500 ml of physiological saline solution was added to a solution of 10 g of a 200 g/LPAH solution for maintenance infusion. (4) At 8:30, the catheter is clamped. At 8:50, 4 ml of venous blood was taken, followed by emptying the bladder and measuring the amount of urine. The bladder was rinsed with 20 ml of physiological saline, and 20 ml of air was injected to drain the fluid in the bladder. The rinse solution was combined with urine, mixed, and 10 ml was taken to determine the PAH content. (5) At 9:10, the first blood sampling and urine retention specimens were repeated; at 9:20, the second blood sampling and urine retention specimens were repeated (same operation 4). (6) Determination of PAH concentration. Mix each time the reagent is added and place for 3 min. The color development was stable (10-15 min) and the blank tube was zeroed at 540 nm, and the absorbance values ​​of the tubes were read. (7) Determination of renal plasma flow. Not suitable for the crowd It is not advisable for pregnant and lactating women to perform this test. Adverse reactions and risks A small number of people may have transient facial flushing, sore back, chest tightness, palpitations and other reactions.