Onset Of Diuresis Research Articles

Renal adaptation to extrauterine life in patients with respiratory distress syndrome.

A spontaneous diuresis that precedes the improvement of pulmonary function has been described in patients with respiratory distress syndrome (RDS). The developmental changes in renal physiology responsible for this spontaneous diuresis are not completely understood. To describe the mechanisms responsible for the spontaneous diuresis, serial renal function studies were performed during the first five days of life in nine premature neonates with RDS. Diuresis was defined as a urine output that was at least 80% of fluid intake; prediuretic, diuretic, and postdiuretic periods were observed in all study infants. Oxygenation did not improve until the postdiuretic period. Renal function studies disclosed a significant increase in free water clearance during the diuresis with the production of dilute urine and a reciprocal rise in serum sodium concentration and plasma osmolality. The glomerular filtration rate increased at the onset of diuresis and remained elevated after the diuresis ended; however, the proportion of filtrate excreted was significantly elevated during the diuresis compared with prediuretic and postdiuretic values. These data suggest that the diuresis in patients with RDS is a water diuresis secondary to an endogenous water load.

146 SEQUENCE AND TIMING OF EVENTS ASSOCIATED WITH SYMP TOMATIC PATIENT DUCTUS ARTERIOSUS (PDA) IN VLBW INFANTS

To observe the timing and sequence of appearance of presenting signs of symptomatic PDA, we continuously and systematically monitored, (1) the onset of diuresis (through intake and output calculation), (2) changes in FiO2, (3) x-ray evidence of increased pulmonary flow, (4) pulse pressure (determined through UA or radial line), (5) pulse pressure/systolic pressure ratio (PP/SBP), (6) daily LA/AO ratio and (7) the first appearance of PDA murmur in 7 VLBW (<1500 gm) infants from birth until most PDA symptoms fully developed. The chain of events began with the onset of diuresis on an average of the 4th day (range 2-8 day) with an abrupt increase in mean urine output of 450% (range 231-775%) compared to the previous day. The FiO2 requirement invariably dropped below 30% one day after the onset of diuresis (i.e. av. 5th day). 12 to 24 hrs later (6th day) the evidence of increased pulmonary flow presented itself on x-rays, this was the time when PP began to widen. By the 7th day of life PP reached 20 mmHg or above and PP/SP ratio exceeded 48% (range 43-55%). Clinical evidence of bounding pulses was obvious at this time. By the 8th day (range 6-llth day) LA/AO ratio had reached >1.2 and on an average of the 9th day (range 7-10th day) the typical PDA murmur finally appeared. Although the timing of appearance may differ in each case, the sequence of events remained the same. Understanding the order of these events helps manage PDA better.

The effect of intravenous contrast medium on glomerular filtration rate.

The changes in glomerular filtration rate (GFR) after intravenous contrast medium have been investigated with three contrast media of differing osmolality (monomer, dimer and non-ionic agent) in antidiuretic dogs with three different basal solute excretion rates. A transient increase in GFR after contrast medium was attributed to the wash-out of medullary creatinine at the onset of diuresis. The subsequent fall in GFR was greatest with the contrast media of higher osmolality and in those dogs without an underlying solute diuresis. With the monomer, the decrease in GFR produced a significant decrease in the amount of contrast medium excreted in the first few minutes after contrast injection. It is suggested that an important factor in the decrease in GFR is the rise in pressure in the renal tubules at the start of a diuresis, before they have had time to dilate. An underlying solute diuresis is considered to protect against the fall in GFR because tubular dilatation has already occurred in response to the basal solute load. The decrease in blood pressure during and after contrast medium injection did not correlate with the fall in GFR.

Effect of delayed graft function and ALG on the circaseptan (about 7-day) rhythm of human renal allograft rejection.

Postimplantation records of 157 kidney transplant recipients with first rejection episodes within 50 days of surgery were studied. Of these 36 had living-related and 121 cadaver donors. Recipients of cadaver donor kidneys were divided into four subgroups: with and without postoperative acute renal failure (ARF), and with and without approximately two weeks of immunosuppression by antilymphoblast globulin (ALG) added to conventional therapy. All recipients with immediate function without ALG showed evidence of periodicity in probability of occurrence of rejection that was highly significant for a 7-day period beginning at the time of surgery. The remaining groups showed less significant periodicity or no significant periodicity beginning at the time of surgery, but they did show a highly significant circaseptan rhythm of rejection episodes beginning with cessation of ALG treatment or with onset of diuresis following ARF in the absence of ALG. It is suggested that clinical manifestation of the immunologic attack of recipient upon graft has an intrinsic development period of about 7 days beginning with implantation. However, initiation of the first period may be blocked by ALG or by low renal blood flow during ARF.

Urinary prostaglandins and kallikrein in the course of acute renal failure

To examine the role of prostaglandins and the kallikrein system in the recovery from acute renal failure, we studied the sequential changes in urinary prostaglandins and kallikrein after the onset of oliguria. The six patients studied had acute tubular necrosis of the vasomotor type. Urinary PGE 2, PGF 2α, the PGF 2α-main urinary metabolite, 6-keto-PGF 1α, and TXB 2 were all measured by radioimmunoassay. Urinary kallikrein was assayed by means of hydrolytic activity using a chromogenic tripeptide substrate. Following onset of diuresis, urinary PGE 2 excretion was increased to normal, parallel to the increase in urine volume. In contrast, the ratio of urinary PGF 2α/PGE 2 peaked at the onset of diuresis, indicating a relative increase in PGF 2α, production at this time. Prior to this peak, urinary kallikrein concentrations reached the highest levels, suggesting a close connection with renal prostaglandin metabolism. On the other hand, changes in PGF 2α-MUM, 6-keto-PGF 1α and TXB 2 were not found. These results indicate that there may be an interlocking acute alteration of the kallikrein-prostaglandin system occurring immediately before the resolution of oliguria, although the role of the acute shift to PGF 2α production observed needs further study.

Changes in pulmonary function during the diuretic phase of respiratory distress syndrome

To evaluate the relationship between improvement in pulmonary function and spontaneous diuresis in respiratory distress syndrome, nine premature infants requiring mechanical ventilation for RDS were studied at a mean age of 11.9 hours prior to the onset of diuresis, at onset of diuresis, at maximum urine output (mean age 44.9 hours), and at 24 hours after maximum urine output. Prior to diuresis functional residual capacity decreased from mean +/- SEM of 16.2 +/- 2 to 13.3 +/- 1.2 ml/kg, and dynamic lung compliance decreased from 2.5 +/- 0.3 to 1.8 +/- 0.3 ml/cm H2O (P less than 0.05), indicating that the respiratory disease was worsening. There was no significant change in alveolar-arterial oxygen gradient, peak inflating pressure, or rate of intermittent mandatory ventilation over this period. At the time of maximum urine output, however, FRC had increased 36% (P less than 0.05). CL had increased by 60% to 2.8 +/- 0.4 ml/cm H2O (P less than 0.025), AaDO2 had decreased from 246 +/- 27 to 184 +/- 30 torr (P less than 0.005), and PIP had decreased from 14.9 +/- 2.2 to 11.3 +/- 2.1 cm/H2O (P less than 0.05). On follow-up study 24 hours after maximum urine output, there was no further significant improvement in FRC, CL or PIP, but IMV rate and AaDO2 continued to decrease. These data show that the pulmonary function in RDS deteriorates until the onset of diuresis, after which it rapidly improves. This diuresis may represent the removal of excess lung liquid and seems necessary for improvement in RDS.

Diagnostic and prognostic significance of an increase in fractional protein clearance ratio before and during rejection of renal transplant.

We measured prospectively changes in fractional protein clearance ratio (CPr/CCr) in 21 live-related (LR) and 41 cadaver donor (CD) renal transplants before and during onset of first rejections. Fifty-three recipients manifested a rejection within the first post-transplant month. Fractional protein clearance increased in all patients during rejection. An increase in CPr/CCr prior to other evidence of impending rejection, and therefore clinically useful, required at least a 10-day rejection-free interval dated from onset of diuresis (whether diuresis was immediate or delayed by acute tubular necrosis (ATN)). Twenty-three of 25 nonantilymphocyte globulin (ALG)-treated CD transplants manifested clinical and laboratory signs of the first rejection episode prior to the 10th day of diuresis compared with 5 of 21 LR and none of 16 ALG-treated CD transplants. Persistence of elevated CPr/CCr despite treatment forecast graft loss (11 of 13), whereas a decrease in this ratio was associated with ultimate reversal of the rejection process.

Acute renal failure following scorpion sting.

Fifteen cases of acute renal failure follwoing scorpion sting were studied. The onset of disease was characterized by the occurrence of hemoglobinuria within 24 h of the sting. Most of the patients developed oliguria, edema, hemolytic anemia, and hemolytic jaundice. Renal failure developed within a few days after the sting, and in five patients was severe enough to need dialysis. The onset of diuresis in oliguric patients occurred between 6 and 21 days following the sting. Renal biopsies were possible in four cases and showed mesangial proliferation, variable degrees of tubular changes, and mild interstitial infiltration. The pathogenesis of acute renal failure in these patients is discussed

Possible urate nephropathy of the newborn infant as a cause of transient renal insufficiency

Oliguric renal failure, bilateral renal enlargement, and hyperuricemia were noted in three term infants. The findings on intravenous pyelography and radionuclide renography were consistent with intratubular obstruction to urinary outflow in two of the infants. The onset of diuresis appeared to follow intravenous pyelography in these infants. Urinary urate crystalluria was prominent in each infant in the first few days after the onset of diuresis, during which normal serum urate concentrations and normal renal function were established.

Medullary sodium depletion during diuresis—a digital computer simulation

An extension is described to a previously published computer simulation of the facultative water-reabsorption process in the mammalian kidney. The simulation has been converted from an analogue- to a digital-computer program. It has been extended to include the effect on the medullary osmolality of the transfer of sodium from the loop of Henle to the vasa recta. In addition, the simulation has been modified to take into account a pressure rise in the medullary interstitial space during the onset of diuresis.

Effect of water deprivation on antidiuresis in Dipodomys spectabilis and Rattus norvegicus

Abstract o 1. Antidiuretic responses of Dipdomys spectabilis and Rattus norvegicus were compared before and after 4 days of water deprivation. 2. Nicotine caused a delay in the onset of diuresis and an increase in urine osmolality and chloride concentration in both species receiving water ad lib . 3. Nicotine induced antidiuresis in the water deprived D. spectabilis , but not in the water deprived R. norvegicus . 4. Azacyclonol produced antidiuresis with associated increases in urine osmolality and chloride concentration in both species before and after water deprivation.

Electrolyte excretion and free-water production during onset of acute diuresis.

The concentration of major urinary solutes was studied in ureteral urine collected at 15- to 30-s intervals at the onset of acute diuresis induced in anesthetized dogs either by high-ceiling diuretics (mainly ethacrynic acid) or by osmotic diuretics. Phosphate/inulin clearance ratios remained unchanged; potassium/inulin clearance ratios rose rapidly. Principal attention is given to the mechanisms underlying a transient rise in urinary sodium and chloride concentrations during the onset of diuresis. When the data are corrected for washout artifacts from the pelvis and ureter, it can be shown that the initial collection periods are associated with a transient increase in free-water production and by the simultaneous secretion of urea from the interstitium into the tubular fluid. The former coincides in time with the rise in urinary chloride concentration and represents an augmentation of water reabsorbed in the collecting duct, which is relatively impermeable to chloride. Both responses are quantitatively consistent with the transition from a hyperosmotic to isosmotic medullary interstitium.

Effect of frusemide on pulmonary blood volume.

Intracardiac frusemide given to seven patients recovering from high-altitude pulmonary oedema caused a significant reduction in the pulmonary blood volume before the onset of diuresis. This supports the suggestion that the mobilization of fluid from the pulmonary circuit is responsible for the relief of symptoms in some patients with pulmonary oedema even when a diuresis does not occur.

PATTERNS OF URINARY EXCRETION OF ALKALINE PHOSPHATASE IN ACUTE RENAL FAILURE.

Abstract The concentration of alkaline phosphatasc in normal urines has been reported as being very low. The present work has confirmed this finding and established a normal range of 0.1–1.0 K.A./100 ml and 1–11 K.A. per 24 h. The presence of an inhibitor which masks some of the enzyme activity but which can be removed by dialysis was confirmed. In serial studies of patients with acute renal failure the normal values were found often to be exceeded. Particularly striking was the great increase in concentration and daily output of the enzyme that occurred with, or just after, the onset of diuresis. Elevations of enzyme activity characteristically took the form of peaks of short duration separated by troughs of lower levels. The origin of the peaks of high phosphatase excretion and their clinical significance are discussed.

Diuresis due to stress in cattle.

IN the course of investigation of some aspects of renal function in adult dairy cattle, it was noted that there was a marked diuretic response to a painful stimulus. The animals used were non-lactating, non-pregnant Ayrshire dairy cows accustomed to experimental procedures, and the stimulus was puncture of the brachial artery by the technique described by Fisher1, which, despite the use of local anaesthetic, always caused some discomfort. Arterial puncture was carried out during continuous urine collection by an indwelling urethral catheter for renal clearance measurements. In association with the increased rate of flow after arterial puncture, urine became noticeably paler in colour, and there was a marked fall in urinary bicarbonate concentration. Cystometric measurement of bladder pressure showed that there was no variation in intracystic pressure at the onset of diuresis, and, on the basis of these observations, it was assumed that the increase in the rate of urine collection was a true reflexion of increased rate of formation, rather than the expulsion of uncollected urine from the bladder.

Pulmonary changes in acute glomerulonephritis in childhood

Summary During a 3 year period (1954 to 1957) all of the 40 cases of acute glomerulonephritis admitted to Booth Hall Hospital for Sick Children, Manchester, were submitted to x-ray examination of the chest. Twenty-five were found to have definite lung changes. Among a further 25 patients of nephritis who had been x-rayed during the 5 year period 1949 to 1954, 12 had radiographic findings similar to those of the original group studied. Segmental or lobar collapse, consolidation, intrapulmonary edema, and pleural effusions were the lesions encountered. They appeared in the first week of the illness and cleared with the onset of diuresis. The majority of these children had some degree of hypertension. There was no correlation with the age of the patients or the degree of azotemia present. An explanatory hypothesis is discussed.

Course of mercurial diuresis during Pitressin infusion in mild congestive heart failure

In an attempt to assess the influence of diminished filtration rate on the renal response to a mercurial diuretic, with particular emphasis on anisosmotic (free) water reabsorption, six patients with mild congestive failure were given Mercaptomerin, 2 ml, i.v., while receiving a constant infusion of Pitressin 2 μ/kg/hr. During the control collection periods, the anisosmotic water reabsorption was less than that encountered previously in a group of normal subjects. With the onset of diuresis, free water reabsorption rose to the same levels as that of normal individuals and, thereafter, followed the same course. The changes observed are compatible with the hypothesis that free water reabsorption is limited by either of two factors, at low flows, the concentration gradient along the tubule and, at higher flows, the maximal ability of the anisosmotic segment to reabsorb water at a given level of hydration and antidiuretic activity. Submitted on November 13, 1958

Prolonged intermittent steroid therapy for nephrosis in children and adults.

Aqueous ACTH, to induce diuresis, was given for at least 12 but preferably for 21 days, unless marked side-effects necessitated earlier cessation of therapy, to patients with nephrosis and clinical and laboratory findings consisting of massive edema, marked proteinuria (3+ to 4+), hypoproteinemia, hyperlipemia, and, in most instances, a lowering of the serum complement activity. Prolonged intermittent therapy with cortisone, given orally, was begun five days after the onset of diuresis but only when diuresis led to complete freedom from edema. After one year, therapy was gradually terminated by prolonging the intervals between maintenance courses rather than by decreasing the daily dosage. Prolonged intermittent steroid therapy not only resulted in an improved prognosis but also permitted the patients to live a more gainful and happy life. The growth and development of these children has remained within normal limits during and after prolonged intermittent maintenance therapy. Continuous steroid therapy, in contrast, has resulted in marked developmental disturbances.

Metabolism of free and conjugated 17-hydroxycorticosteroids in subjects with uremia.

In subjects with chronic renal disease, levels of free 17-hydroxycorticosteroids (17-OHCS) in plasma were measured at 8 a.m. and were normal. Conjugated levels were elevated, correlating inversely with endogenous creatinine clearance (Clcr.). After standard infusions of cortisol, free levels decayed exponentially but more slowly than normal, while conjugated levels rose further than in normal subjects. Conjugated, but not free, 17-OHCS again correlated inversely with Clcr. Cortisol was partially identified in the free fraction and tetrahydrocortisol and tetrahydrocortisone in the conjugated fraction of plasma following infusion. Urinary excretion of 17-OHCS and the increment after infusion were less than normal and correlated directly with Clcr. A patient with anasarca provided an exception to the noted patterns and correlations. In subjects with acute renal failure, elevated levels of conjugated 17-OHCS in plasma did not decline with the onset of diuresis but fell in parallel with levels of blood urea. D...

EFFECT OF ADRENOCORTICOTROPIC HORMONE (ACTH) AND CORTISONE ON PROTEINURIA AND HEMATURIA IN THE NEPHROTIC SYNDROME

1. Fifteen children suffering from the nephrotic syndrome were treated with 22 courses of either ACTH or cortisone. Three children failed to have a diuresis during 4 courses of treatment. No decrease in proteinuria was noted. Eighteen courses of hormone treatment resulted in diuresis in 12 patients. A decrease in proteinuria preceded diuresis in each instance. [See Table II, Fig. 2 and Fig. 3 in Source Pdf] 2. A relationship between severity of hypoproteinemia and onset of diuresis, once proteinuria has started to decrease, has been established. 3. It is concluded that one of the important actions of ACTH or cortisone in inducing diuresis is concerned with the decrease in proteinuria, resulting in increasing plasma protein concentration and oncotic pressure. 4. The effect of these hormones on hematuria in nephrosis has been noted during 4 courses of treatment. In these proteinuria decreased appreciably. In 4 instances hematuria persisted and proteinuria decreased only slightly or not at all.