***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: W hat n ~ les of evidence should apply when evpert committees meet to generate recommendations for the clinical management of patients ? Should only the thoroughly vali date d results of r and omized clinical trials be admissible to avoid or minimize the application of useless or harmful therapy ? Or , to maximize the potential benefits to patients ( inclr ~ ding those possible from unproved remedies ) , should a synthesis of the experiences of experienced clinicians form the basis for such recommendations ? Ample precedent exists for the latter approach even when attempts are made to replace it . ' However , for the following reasons , the nonexperimental evidence that forms the recalled experiences of seasoned clinicians will tend to overestimate efficacy : A r and omized study was conducted on 66 patients with acute established oliguric renal failure .  Intravenous doses of furosemide ranging from 1.5 to 6.0 mg/kg were given every 4 h to 33 of the patients ; the remaining 33 patients served as controls . A persisting diuretic response was observed in 5 treated patients and in 2 controls . Hemodialyses were required in most of them . Furosemide did not significantly modify in cured patients the mean oliguric period , the number of dialyses and the mean period of renal insufficiency Thirty-six patients with preoperative renal dysfunction were studied to evaluate the effects of dopamine ( D ) and dopamine-nitroprusside ( DN ) on renal function during cardiopulmonary bypass ( CPB ) . No differences from the control group ( C ) were found in creatinine clearance , fractional sodium excretion , osmolarity and free-water clearance . Sodium output/intake ratio during CPB was higher in group D than in groups C and DN ( P less than 0.05 ) ; water output/intake ratio was higher in group D than in group C ( P less than 0.05 ) . Urine lysozime levels and alpha-glycosidase/creatinine ratios increased similarly in the three groups , suggesting ischemic tubular cell damage . No patients showed acute postoperative renal failure or a worsening of their renal dysfunction . The data suggest an increased water and sodium excretion during CPB with a dopamine infusion , possibly result ing from a renal vasodilator effect that was abolished by simultaneous nitroprusside administration Fifty-eight patients in established acute renal failure following trauma or surgery were allocated in a prospect i ve and r and om fashion to two different diuretic regimes . In the control group , 1 g frusemide was given as a single injection over four hours . In the test group , frusemide was then continued either intravenously or orally in a dose of 3 g/24 hr until a urine output of 200 ml/hr was sustained or until the plasma creatinine fell below 300 mumoles/l . Oliguria was reversed or prevented in 24 of 28 patients given sustained frusemide , but in only 2 patients given a single injection . However , the number of dialyses and duration of renal failure and mortality were not different in the two groups . The serious complication of deafness occurred in two patients and in one of them this was permanent Previous studies suggest a role for renal vasoconstriction in the pathogenesis of radiocontrast-induced nephropathy ( RCIN ) . A renal vasodilator such as dopamine may be protective . However , the effect of dopamine on renal blood flow ( RBF ) in patients with chronic renal failure ( CRF ) is controversial . Patients with CRF of diabetic ( DM ) or nondiabetic ( NDM ) origin were hydrated with 0.45 % NaCl intravenously at 100 mL/h for 12 h and then r and omized to either 0.45 % NaCl IV at 100 mL/h ( Group 1 ) or dopamine IV at 2 micrograms/kg/min in 0.45 % NaCl at 100 mL/h for 2 h during and after cardiac catheterization . Mean arterial pressure ( MAP ) , cardiac output ( CO ) , and RBF were measured at baseline ( t = 0 ) , after 5 min of vehicle ( Group 1 ) or dopamine ( Group 2 ) but before ionic radiocontrast ( t = 5 min ) , after ventriculogram ( t = 15 min ) , and after coronary angiography ( t = 65 min ) . Serum creatinine ( SCr ) was measured at baseline and 24 and 48 h after cardiac catheterization . RCIN was defined as a 25 % increase of SCr above baseline 48 h after cardiac catheterization . Baseline characteristics demonstrated the groups to be equivalent in age , SCr , creatinine clearance , CO , MAP , RBF , and radiocontrast dose administered . The incidence of RCIN was not different between Group 1 and Group 2 ( Group 1 , 6 of 15 patients ; Group 2 , 5 of 15 patients ) . Dopamine infusion was associated with a significant increase in RBF at 5 min ( Group 1 , 110 + /- 13 % ; Group 2 , 193 + /- 40 % at t = 5 , p < .05 ) . RBF remained elevated throughout the catheterization in Group 2 . ( ABSTRACT TRUNCATED AT 250 WORDS PURPOSE To evaluate the protective effect of low-dose dopamine given as continuous infusion in patients who undergo chemotherapy with the nephrotoxin cisplatin . PATIENTS AND METHODS Forty-two patients who received high-dose cisplatin-containing chemotherapy entered a prospect i ve , r and omized , double-blind , placebo-controlled trial . Twenty-one patients received dopamine , and 21 received placebo .  Patients were to receive either infusional dopamine 2 micrograms/kg/min over 48 hours or placebo . Cisplatin 125 mg/m2 was administered 12 hours after initiating dopamine ( group D ) or placebo ( group P ) . This schedule was repeated twice , 1 week apart . Measurements of serum creatinine , urinary electrolytes and creatinine , urinary excretion of epidermal growth factor ( EGF ) , ototoxicity , parameters of hematopoietic recovery , and duration of hospitalization were analyzed . RESULTS We observed an increase in serum creatinine level to a peak of 1.9 mg/dL ( range , 0.8 to 7.8 ) in the dopamine group , in comparison to 1.4 mg/dL ( range , 0.9 to 3.3 ) in the placebo group ( P = .04 ) . Urinary magnesium excretion increased and EGF excretion decreased in both groups . Urinary sodium , chloride , and potassium excretion were increased in both groups , but more so in the placebo group . Dopamine had no measurable effect on hearing loss , duration of hospitalization , or hematopoietic recovery . CONCLUSION The use of prophylactic dopamine increased peak serum creatinine levels relative to placebo and failed to prevent cisplatin-induced renal toxicity or ototoxicity . Determination of whether dopamine could reverse chemotherapy-induced renal damage would require a r and omized prospect i ve trial BACKGROUND Injections of radiocontrast agents are a frequent cause of acute decreases in renal function , occurring most often in patients with chronic renal insufficiency and diabetes mellitus . METHODS We prospect ively studied 78 patients with chronic renal insufficiency ( mean [ + /- SD ] serum creatinine concentration , 2.1 + /- 0.6 mg per deciliter [ 186 + /- 53 mumol per liter ] ) who underwent cardiac angiography .  The patients were r and omly assigned to receive 0.45 percent saline alone for 12 hours before and 12 hours after angiography , saline plus mannitol , or saline plus furosemide . The mannitol and furosemide were given just before angiography . Serum creatinine was measured before and for 48 hours after angiography , and urine was collected for 24 hours after angiography . An acute radiocontrast-induced decrease in renal function was defined as an increase in the base-line serum creatinine concentration of at least 0.5 mg per deciliter ( 44 mumol per liter ) within 48 hours after the injection of radiocontrast agents . RESULTS Twenty of the 78 patients ( 26 percent ) had an increase in the serum creatinine concentration of at least 0.5 mg per deciliter after angiography . Among the 28 patients in the saline group , 3 ( 11 percent ) had such an increase in serum creatinine , as compared with 7 of 25 in the mannitol group ( 28 percent ) and 10 of 25 in the furosemide group ( 40 percent ) ( P = 0.05 ) . The mean increase in serum creatinine 48 hours after angiography was significantly greater in the furosemide group ( P = 0.01 ) than in the saline group . CONCLUSIONS In patients with chronic renal insufficiency who are undergoing cardiac angiography , hydration with 0.45 percent saline provides better protection against acute decreases in renal function induced by radiocontrast agents than does hydration with 0.45 percent saline plus mannitol or furosemide OBJECTIVE To determine the effect on renal function of postoperative continuous , intravenous furosemide  after major thoraco-abdominal or vascular surgery . DESIGN R and omized , double-blind , placebo-controlled trial . SETTING Intensive care unit of a referral hospital in Eastern Switzerl and . METHODS Furosemide ( 1 mg/h ) or placebo was administered to 121 consecutive patients admitted to the intensive care unit after major abdominal , chest or vascular surgery and continued throughout the intensive care treatment period . Enrollment was performed during a 6 months period . No patient was excluded .  Renal function was determined serially by measuring creatinine clearances and plasma creatinine concentrations . RESULTS Postoperatively , creatinine clearance decreased significantly to 83 % ( furosemide ) and to 81 % ( placebo group ) of the initial value ( p = 0.004 ) . This decrease was not affected significantly by furosemide . Retrospective subgroup analysis using stepwise regression also did not show any differences between the groups . Hypokalemia was detected in 36 ( furosemide ) versus 19 % of the blood sample ( placebo , p = 0.006 ) . CONCLUSIONS Low-dose intravenous furosemide appears to offer no advantage over placebo in an unselected group of patients with moderate postoperative renal impairment . As no patients with acute renal failure necessitating dialysis were observed during the study period , the effect of furosemide in more severe postoperative renal impairment and the effects of higher doses of loop diuretics remain to be investigated We have compared low dose dopamine with dobutamine in conserving renal function in 142 children younger than 10 yr undergoing cardiopulmonary bypass ( CPB ) . Patients were allocated r and omly to receive a continuous infusion of either dopamine 2.5 micrograms kg-1 min-1 ( group 1 ) or dobutamine 2.5 micrograms kg-1 min-1 ( group 2 ) from the time of induction of anaesthesia . Administration of inotropes and diuretics was controlled strictly to agreed regimens . There was no clinical or statistically significant difference between the two groups in postoperative urine output , serum concentration of creatinine , fractional sodium excretion or need for diuretic therapy . This was true also of the subgroup of patients who received no other inotropic support . However , the subgroup of patients in group 1 who underwent periods of CPB in excess of 2 h ( n = 17 ) had persistently greater postoperative serum concentrations of creatinine . Low dose dopamine did not appear to be superior to dobutamine for protection of renal function in these patients Objective : Low‐dose dopamine has been used in critically ill patients to minimize renal dysfunction without sufficient data to support its use . The aim of this study was to determine whether low‐dose dopamine improves renal function , and whether dobutamine , a nondopaminergic inotrope , improves renal function . Design : Prospect i ve , r and omized , double‐blind trial . Patients : Twenty‐three patients at risk for renal dysfunction were entered into the study . Five patients were later withdrawn . Study data for the remaining 18 patients were : mean age 55 yrs ; mean Acute Physiology and Chronic Health Evaluation ( APACHE ) II score of 18 ; mean weight 71 kg ) . The following conditions were present : mechanical ventilation ( n = 17 [ inverse‐ratio ventilation , n = 6 ] ) ; inotrope administration ( n = 11 ) ; sepsis ( n = 13 ) ; and adult respiratory distress syndrome or multiple organ failure syndrome ( n = 9 ) . Interventions : The study patients were administered dopamine ( 200 & mgr;g/min ) , dobutamine ( 175 & mgr;g/min ) , and placebo ( 5 % dextrose ) over 5 hrs each in a r and omized order . Ventilator setting s , fluid management , and preexisting inotropic support were not altered during the study . Measurements and Main Results : Systemic hemodynamic values and indices of renal function ( 4‐hr urine volume , fractional excretion of sodium , and creatinine clearance ) were measured during the last 4 hrs of each infusion . Dopamine  
    Output:
    
Level I evidence exists against the use of  diuretics  for radiocontrast-induced acute tubular necrosis , and loop diuretics given after vascular surgery .
There is level II evidence that diuretics do not improve outcome in patients with established acute renal failure .
Level II evidence also exists against the use of dopamine in the prevention of acute tubular necrosis in multiple subsets of patients .
Conclusions Routine use of diuretics or dopamine for the prevention of acute renal failure can not be justified on the basis of available evidence