Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022672 (acute tubular necrosis)
 2,175 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

UW (University of Wisconsin) solution, formulated by Belzer's team in Madison, has already been proved to increase cold ischemia time in liver and pancreas preservation. A multicentre clinical trial is being conducted to compare renal preservation in human transplantation using two different solutions: UW and Eurocollins (EC). This paper, whose results will be included in the multicentre trial, reports local comparative results between UW and EC perfused Kidneys. The two donor populations UW (28 cases) and EC (47 cases) were not randomized. They were however comparable in renal function prior to harvesting but not in age (35 +/- 13.4 years EC versus 27.7 +/- 12.4 years UW). The two recipient populations (48 EC versus 48 UW) were more homogeneous. Comparative results were significant with better graft function in the UW group: creatinine at one week: 499.2 +/- 296.3 EC versus 277.6 +/- 226.2 mumol/l, p less than 0.0001; creatinine at one month: 228.7 +/- 135 EC versus 159.7 +/- 135.6 mumol/l, p less than 0.02 and a decrease in acute tubular necrosis (39.5% EC versus 14.5% UW) and hospital stay. These results justify the use of UW solution by intraaortic flush especially during multi-organ procurement.
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PMID:[Comparative study of the University of Wisconsin solution versus Eurocollins in kidney transplant]. 248 9

Damage sustained by an ischaemic kidney is reduced by cooling the organ. For this reason kidneys are rapidly cooled during the retrieval operation and preserved at low temperature before implantation. When the kidney is removed from cold storage for implantation into the recipient it gradually rewarms (second warm ischaemic time) and a prolonged second warm ischaemic time has been shown to be a cause of acute tubular necrosis following transplantation. The temperature rise in a kidney during implantation has been poorly investigated and little work to minimize that rise has been carried out. This study investigates, in an animal model, the changes that occur in the core temperature of kidneys during the second warm ischaemic time. A jacket has been designed which greatly reduces the rate of kidney rewarming during simulated operative conditions. Kidneys unprotected by the test system showed a rapid rise in temperature from a mean of 1 degrees C to a mean of 20 degrees C after 45 min, compared with those kidneys placed in the protective jacket in which the temperature rose to a mean of only 8 degrees C in the same time. The jacket is not bulky and is simple to use. Maintaining a low kidney core temperature during the second warm ischaemic time will reduce injury to the kidney and should be part of routine clinical practice.
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PMID:Reducing renal injury during transplantation. 234 Apr 4

On the basis of 88 consecutive cadaveric renal transplants, multiple variables concerning donor conditioning and perioperative recipient management which may have an influence on the occurrence of acute tubular necrosis (ATN), were analysed and their impact on long-term results assessed. Cold ischaemia time turned out to be the greatest risk factor and was seven hours shorter in patients with good initial function when compared with patients with ATN. Although actual one-year graft survival was similar in both groups, the postoperative course was more complicated in the ATN group and management more onerous. Furthermore, two patients of the initial non-function group died of complications directly related to renal replacement therapy. Seventeen hours cold ischaemia time was associated with more than 80% initial function. This time is sufficient to allow careful tissue typing and organ transportation.
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PMID:[The effect of donor conditioning and perioperative management of recipients on the initial and late function of kidney transplants]. 260 69

A group of 40 cadaveric kidneys was studied just prior to planned transplantation to further assess the applicability of 31P-MRS in the analysis of clinical renal transplant viability. Renal intracellular high-energy phosphorus metabolites (ATP [or NADP], phosphomonoester [PME] and inorganic phosphate [Pi]) and pH were measured noninvasively with MRS surface coils external to cold storage containers. Pretransplant MRS parameters were correlated with subsequent renal function in recipient patients (measured one week postoperatively by the need of dialysis, drop in serum creatinine, urine output, and 123I or 131I Hippuran assessed renal tubular function). ATP and NADP was detected in eleven kidneys and was significantly (P less than 0.001) associated with the best renal function posttransplantation. These kidneys also had the highest PME/Pi ratios (1.66-0.54), while lower ratios (0.36-0.10) were associated with prolonged acute tubular necrosis. The PME/Pi ratios significantly (P less than 0.0001) correlated with subsequent clinical renal function, whereas cold storage times (37 +/- 10 hr) or intracellular renal pH (6.53-7.91) did not. These preliminary data suggest that MRS is a noninvasive, nondestructive and sterile method for assessing clinical viability during hypothermic storage of human cadaver kidneys and the subsequent recovery of renal function postrenal transplantation.
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PMID:Pretransplant assessment of renal viability by phosphorus-31 magnetic resonance spectroscopy. Clinical experience in 40 recipient patients. 266 35

The short or injured renal vein in cadaveric transplantation is a surgical challenge. Over a 2-year period, we have performed ex vivo renal vein lengthening with an interposition vascular allograft in 17 recipients of cadaveric kidneys. Indications for renal vein extension allografts were a short right renal vein (N = 12), procurement injury to the vein (N = 4), and double renal vein (N = 1). In six cases (35.3%), ex vivo renal artery reconstruction was performed in combination with the venous repair. Our preferred approach is to employ allograft material in ex vivo reconstruction under cold storage conditions. Bench surgery ranged from 10 to 30 min, and the mean in situ anastomosis time was 20 min. The mean length of renal vein prior to reconstruction was 12 mm, and the mean length of venous interposition allograft after revascularization was 27 mm. There were no episodes of vascular thrombosis or primary nonfunction. Three patients (17.6%) required postoperative hemodialysis for acute tubular necrosis, which was subsequently resolved. The mean serum creatine at 1 month post-transplant was 1.7 mg/dl. These preliminary results suggest that ex vivo renal vein reconstruction with an interposition allograft is a safe and effective modality which should be added to the transplant surgeon's armamentarium in select cases.
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PMID:Renal vein reconstruction with interposition allografts in cadaveric renal transplantation. 307 86

Reperfusion injury is increasingly recognized as a key factor in the development of posttransplant acute tubular necrosis. Previous studies have shown that addition of the calmodulin inhibitor trifluoperazine (TFP) to Collins' flush solution protected the cortical microcirculatory integrity and dramatically improved renal viability after transplantation. The present report describes the protective effect(s) of TFP in the course of reperfusion injury. Twenty mongrel dogs underwent bilateral nephrectomy; in each instance, the left kidney was flushed immediately with 250 ml of cold Collins' solution, and the right kidney was flushed with the same solution containing TFP, 5 mg/L. After 48 and 72 hr of preservation, each kidney was connected through silastic shunts to the femoral vessels of another dog. The mean renal blood flow (RBF) immediately after reperfusion was 2.2 ml/g/min and 1.7 ml/g/min in the left and right kidneys, respectively, and was similar to mean RBF measurements prior to nephrectomy. After 15 min of reperfusion, there was a sharp decrease in mean RBF in the Collins' flushed kidneys, which persisted after 60 min of reperfusion (0.37 ml/g/min). In contrast, there was only a mild decrease in mean RBF in the TFP-flushed kidneys (1.27 ml/g/min). A partial explanation for the favorable effect of TFP may be related to the inability of the ischemic cell to handle the increased calcium load associated with reperfusion (calcium paradox). In a test of this possibility, 0.5 mg/kg of verapamil, a calcium channel blocker, was infused during reperfusion. No beneficial effects of this drug were noted in either Collins' or TFP-flushed kidneys (n = 10). However, when 1.25 mg/kg of captopril, an angiotensin-converting enzyme inhibitor, was infused at the time of reperfusion, a dramatic amelioration of the reperfusion injury occurred in the Collins' flushed kidneys (1.2 ml/g/min) (n = 10). Taken together, these data suggest that the damage to cold-preserved kidneys flushed with Collins' solution alone may occur at the time of actual reperfusion. Such reperfusion damage is ameliorated by TFP and captopril. The known relationship between calcium and the effect of angiotensin on the vascular smooth muscle cell may explain in part the protective role of calcium inhibitors placed in preserved kidneys prior to reperfusion.
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PMID:The protective effect of calcium inhibitors and of captopril on the renal microcirculation during reperfusion. 309 41

Acute tubular necrosis is a frequent occurrence following hypovolemic shock and human renal transplantation. Although this postischemic injury was originally thought to result from ischemia alone, it has recently been recognized that significant tissue injury can occur during the period of reperfusion. The demonstration of the oxygen free-radical-mediated postischemic reperfusion injury by Granger, Rutili, and McCord in ischemic cat intestine suggested that this mechanism might also be operative following renal ischemia. In the kidney, postischemic injury results in necrosis of the proximal renal tubule and accumulation of erythrocytes in the outer renal medulla. It has been proposed that the primary event leading to these pathologic changes is a free-radical-mediated injury to the endothelial cells in the inner stripe of the outer medulla. Experimental evidence in animals subjected to warm and cold ischemia supports a free-radical-mediated mechanism. The clinical significance of these findings is demonstrated in preclinical animal studies of renal transplantation in which approximately two-thirds of the injury following cold ischemia could be ablated by superoxide dismutase administered just prior to reperfusion or by allopurinol when administered both at the time of preservation and reperfusion or at the time of preservation alone.
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PMID:Free-radical-mediated postischemic reperfusion injury in the kidney. 329 86

Calcium channel blockade has been shown to prevent warm renal ischemic damage. The ability of verapamil to decrease the severity of acute tubular necrosis (ATN) after 24-hr cold storage and autotransplantation was studied in a randomized paired study of 12 dogs. Experimental animals pretreated with intraarterial verapamil and flushing of the harvested kidney with cold intracellular solution containing verapamil demonstrated significantly (P less than .05) greater renal function preservation over their matched controls. A subsequent nonpaired study of 6 dogs treated only with flushing of the harvested kidney with perfusate containing verapamil demonstrated no significant preservation advantage over controls. We conclude that verapamil, administered prior to the ischemic event, can enhance the protective effect of hypothermia and decrease the severity of ATN in ischemically injured kidneys.
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PMID:The effect of verapamil in reducing the severity of acute tubular necrosis in canine renal autotransplants. 330 60

To assess the applicability of phosphorus-31 magnetic resonance spectroscopy (31P-MRS) in the analysis of renal transplant viability and preservation techniques with respect to pre-transplant ischemia, we studied two rat groups. Twenty-five rat kidneys were subjected to various time increments of warm ischemia (Group A), and 31P-MRS was performed on each kidney at time intervals of up to 72 hours during simple hypothermic storage. We correlated findings of 31P-MRS with simultaneous findings of electron microscopic (EM) ultrastructural viability parameters (in Group A) and subsequent survival and renal function in 30 rats (Group B) subjected to similar amounts of variable ischemia. Intracellular phosphorus metabolite levels were nondestructively monitored by 31P-MRS via spectral peaks of NAD, sugar monophosphates (SP), and inorganic phosphate (Pi). We concluded: SP/Pi and NAD/Pi ratios decay in a time-dependent manner for both warm and cold ischemia, although this process is much slower during cold storage; EM viability parameters correlate with the development of acute tubular necrosis (irreversible damage) versus nonviability (gross cell death) on a qualitative basis only; and 31P-MRS enables a quantitative assessment of renal viability and ischemic renal damage and can predict the degree of acute tubular necrosis and post-ischemic renal function. 31P-MRS is potentially a noninvasive, nondestructive method of assessing viability during simple hypothermic storage of the rat kidney. Preliminary evidence shows that this MRS method can be applied to human kidney viability studies for clinical renal transplantation and urologic research concerning renal preservation.
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PMID:Assessment of renal viability by phosphorus-31 magnetic resonance spectroscopy. 351 65

High doses of furosemide have been reported to reduce the requirement for dialysis following cadaveric kidney transplantation. Depending on recipient age, alternate cadaver kidney transplant recipients received infusions of 200 to 400 mg. furosemide just before restoration of renal circulation. All recipients received infusions of mannitol during the hour before renal revascularization. All 50 kidneys were preserved with intracellular electrolyte solutions. Mean cold storage times (33.4 plus or minus 11.4 hours for recipients given furosemide versus 35.7 plus or minus 12.3 hours for controls) were not significantly different between the 2 groups. There were no significant differences in first week dialysis requirement between recipients given furosemide and controls (75 versus 73 per cent, respectively), first day urine output (2.2 plus or minus 4.2 versus 1.0 plus or minus 0.81., respectively), 1-month serum creatinine nadirs (2.1 plus or minus 1.1 versus 1.9 plus or minus 1.1 mg . per dl., respectively) and 1-month function rate (92 versus 92 per cent, respectively). High doses of furosemide did not prevent significant acute tubular necrosis following human cadaveric kidney transplantation when the recipients also received infusions of mannitol.
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PMID:Effect of furosemide on dialysis requirement following cadaveric kidney transplantation. 388 74


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