***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: Objective To investigate the adrenocortical function in brain-dead patients , potential organ donors . Design Prospect i ve study . Setting Intensive care units in two teaching hospitals . Patients A total of 37 patients ( 28 men , nine women ) with severe brain injury , having a mean age of 42 ± 18 yrs , were included in the study . Group A consisted of 20 brain-injured patients who did not deteriorate to brain death . Group B included 17 brain-injured patients who were brain dead ; of these , ten patients developed brain death during ICU stay and seven patients were admitted to the ICU after clinical brain death . Interventions In all patients ( group A and group B ) , a morning blood sample was obtained at admission to the ICU to determine baseline plasma cortisol . Subsequently , 1 & mgr;g of corticotropin ( adrenocorticotropic hormone , Synacthen ) was administered intravenously , and a blood sample was taken 30 mins after the injection . In group B patients who became brain dead while being treated in the ICU ( n = 10 ) , the same procedure was repeated the morning after the confirmation of brain death . Patients having a cortisol level of at least 18 & mgr;g/dL after the administration of adrenocorticotropic hormone were defined as responders . Measurements and Main Results After the occurrence of brain death , group B patients had significantly lower values for baseline ( 8.5 ± 6.2 vs. 17.0 ± 6.6 & mgr;g/dL , p < .001 ) and stimulated ( 16.9 ± 6.3 vs. 23.9 ± 5.7 & mgr;g/dL , p = .001 ) plasma cortisol compared with group A patients . Thirteen group B patients ( 76 % ) and two group A patients ( 10 % ) were nonresponders to adrenocorticotropic hormone ( p < .001 ) . In group B patients , baseline and stimulated cortisol concentrations were significantly related ( r = .71 , p = .001 ) , whereas there was no correlation between baseline cortisol and the increment in cortisol ( r = −.37 , p = .15 ) . Mean hormonal data of the ten brain-dead patients studied at admission in the ICU and after the occurrence of brain death were the following : baseline plasma cortisol ( 23.5 ± 11.4 vs. 6.8 ± 4.2 & mgr;g/dL , p = .003 ) and stimulated serum cortisol ( 28.8 ± 9.9 vs. 16.3 ± 4.3 & mgr;g/dL , p = .008 ) . Conclusions Adrenal cortisol secretion after dynamic stimulation is deficient in a substantial proportion of brain-dead potential organ donors 34 cadaveric donor grafts were r and omized in a blind study of the effect of pretreatment of 5 g each of methylprednisolone and cyclophosphamide on kidney graft outcome . There was no difference in overall survival or functioning after 3 , 6 or 12 months between grafts from pretreated ( 33 kidneys ) or control ( 29 kidneys ) cadaveric donors . In addition , this pretreatment protocol did not modify the recipient immune response against B-lymphocyte alloantigens which developed in unsuccessful transplants . Our data , thus , neither confirm the high rate of kidney graft survival attributed to cadaveric donor treatment nor the supposition that treatment is effective in suppressing recipient antidonor B-lymphocyte antibodies BACKGROUND  Posttransplantation acute renal failure ( ARF ) occurs in roughly 25 % of recipients of organs from deceased donors . Inflammation in the donor organ is associated with risk for ARF . OBJECTIVE To determine whether administering corticosteroids to deceased organ donors reduces the incidence and duration of ARF in organ recipients more than placebo . DESIGN Parallel , blocked r and omized trial , performed between February 2006 and November 2008 , with computer-generated r and omization and central ized allocation . Investigators were masked to group assignment . ( Controlled-trials.com registration number : IS RCT N78828338 ) SETTING : 3 renal transplantation centers in Austria and Hungary . PATIENTS 306 deceased heart-beating donors and 455 renal transplant recipients . INTERVENTIONS Organ donors were administered an intravenous infusion of either 1000 mg of methylprednisolone ( 136 donors ) or placebo ( 0.9 % saline ) ( 133 donors ) at least 3 hours before organ harvesting . MEASUREMENTS Incidence of ARF , defined as more than 1 dialysis session in the first week after transplantation , was the primary end point . Secondary and other end points included duration of ARF and trajectories of serum creatinine level . The suppression of immune response and inflammation by the intervention was assessed in the donor organ on a genome-wide basis . RESULTS 52 of 238 recipients ( 22 % ) of kidneys from steroid-treated donors and 54 of 217 recipients ( 25 % ) of kidneys from placebo-treated donors had ARF ( difference , 3 percentage points [ 95 % CI , -11 to 5 percentage points ] ) . One graft was lost on day 1 in each group , and 1 recipient in the placebo group died of cardiac arrest on day 2 . The median duration of ARF was 5 days ( interquartile range , 2 days ) in the steroid group and 4 days ( interquartile range , 2 days ) in the placebo group ( P = 0.31 ) . The groups had similar trajectories of serum creatinine level in the first week ( P = 0.72 ) . Genomic analysis showed suppressed inflammation and immune response in kidney biopsies from deceased donors who received corticosteroids . LIMITATION Donors and recipients were mainly white , and all were from 3 transplantation centers in central Europe , which may limit generalizability . CONCLUSION Systemic suppression of inflammation in deceased donors by corticosteroids did not reduce the incidence or duration of posttransplantation ARF in allograft recipients . PRIMARY FUNDING SOURCE Austrian Science Fund and Austrian Academy of Science OBJECTIVE To test the reliability and validity of specific instructions to classify blinding , when unclearly reported in r and omized trials , as " probably done " or " probably not done . " STUDY DESIGN AND SETTING We assessed blinding of patients , health care providers , data collectors , outcome adjudicators , and data analysts in 233 r and omized trials in duplicate and independently using detailed instructions . The response options were " definitely yes , " " probably yes , " " probably no , " and " definitely no. " We contacted authors for data verification ( 46 % response ) . For each of the five questions , we assessed reliability by calculating the agreement between the two review ers and validity by calculating the agreement between review ers ' consensus and verified data . RESULTS The percentage with unclear blinding status varied between 48.5 % ( patients ) and 84.1 % ( data analysts ) . Reliability was moderate for blinding of outcome adjudicators ( κ=0.52 ) and data analysts ( κ=0.42 ) and substantial for blinding of patients ( κ=0.71 ) , providers ( κ=0.68 ) , and data collectors ( κ=0.65 ) . The raw agreement between the consensus record and the author-verified record varied from 84.1 % ( blinding of data analysts ) to 100 % ( blinding of health care providers ) . CONCLUSION With the possible exception of blinding of data analysts , use of " probably yes " and " probably no " instead of " unclear " may enhance the assessment of blinding in trials AIMS The aim of this study was to assess the haemodynamic effects of tri-iodothyronine ( T3 ) and methylprednisolone in potential heart donors . METHODS AND RESULTS In a prospect i ve r and omized double-blind trial , 80 potential cardiac donors were allocated to receive T3 ( 0.8 microg kg(-1 ) bolus ; 0.113 microg kg(-1 ) h(-1 ) infusion ) ( n = 20 ) , methylprednisolone ( 1000 mg bolus ) ( n = 19 ) , both drugs ( n = 20 ) , or placebo ( n = 21 ) following initial haemodynamic assessment . After hormone or placebo administration , cardiac output-guided optimization was initiated , using vasopressin as a pressor and weaning norepinephrine and inotropes . Treatment was administered for 5.9 + /- 1.3 h until retrieval or end- assessment . Cardiac index increased significantly ( P < 0.001 ) but administration of T3 and methylprednisolone alone or in combination did not affect this change or the heart retrieval rate . Thirty-five per cent ( 14/40 ) of initially marginal or dysfunctional hearts were suitable for transplant at end- assessment . At end- assessment , 50 % of donor hearts fulfilled criteria for transplant suitability . CONCLUSION Cardiac output-directed donor optimization improves donor circulatory status and has potential to increase the retrieval rate of donor hearts .  Tri-iodothyronine and methylprednisolone therapy do not appear to acutely affect cardiovascular function or yield In the GRADE approach , r and omized trials start as high- quality evidence and observational studies as low- quality evidence , but both can be rated down if most of the relevant evidence comes from studies that suffer from a high risk of bias . Well-established limitations of r and omized trials include failure to conceal allocation , failure to blind , loss to follow-up , and failure to appropriately consider the intention-to-treat principle . More recently recognized limitations include stopping early for apparent benefit and selective reporting of outcomes according to the results . Key limitations of observational studies include use of inappropriate controls and failure to adequately adjust for prognostic imbalance . Risk of bias may vary across outcomes ( e.g. , loss to follow-up may be far less for all-cause mortality than for quality of life ) , a consideration that many systematic review s ignore . In deciding whether to rate down for risk of bias -- whether for r and omized trials or observational studies -- authors should not take an approach that averages across studies . Rather , for any individual outcome , when there are some studies with a high risk , and some with a low risk of bias , they should consider including only the studies with a lower risk of bias Introduction Circulatory failure during brain death organ donor resuscitation is a problem that compromises recovery of organs . Combined administration of steroid , thyroxine and vasopressin has been proposed to optimize the management of brain deceased donors before recovery of organs . However the single administration of hydrocortisone has not been rigorously evaluated in any trial . Methods In this prospect i ve multicenter cluster study , 259 subjects were included . Administration of low-dose steroids composed the steroid group ( n = 102 ) . Results Although there were more patients in the steroid group who received norepinephrine  before brain death ( 80 % vs. 66 % : P = 0.03 ) , mean dose of vasopressor administered after brain death was significantly lower than in the control group ( 1.18 ± 0.92 mg/H vs. 1.49 ± 1.29 mg/H : P = 0.03 ) , duration of vasopressor support use was shorter ( 874 min vs. 1160 min : P < 0.0001 ) and norepinephrine weaning before aortic clamping was more frequent ( 33.8 % vs. 9.5 % : P < 0.0001 ) . Using a survival approach , probability of norepinephrine weaning was significantly different between the two groups ( P < 0.0001 ) with a probability of weaning 4.67 times higher in the steroid group than in the control group ( 95 % CI : 2.30 – 9.49 ) . Conclusions Despite no observed benefits of the steroid administration on primary function recovery of transplanted grafts , administration of glucocorticoids should be a part of the resuscitation management of deceased donors with hemodynamic instability BACKGROUND Lung transplantation activity is frustrated by donor lung availability . We sought to examine the effect of active donor management and hormone administration on pulmonary function and yield in cadaveric heart-beating potential lung donors . METHODS We studied 182 potential lung donors ( arterial oxygen tension [PaO2]/fractional inspired oxygen [ FIO2 ] ratio > or = 230 ) . From this group , 60 patients ( 120 lungs ) were allocated , within a r and omized trial , to receive methylprednisolone ( 1 g ) , triiodothyronine ( 0.8 microg/kg bolus and 0.113 microg/kg/h infusion ) , both methylprednisolone and triiodothyronine , or placebo as soon as feasible after consent and initial assessment . Trial donors underwent protocol -guided optimization of ventilation and hemodynamics , lung water assessment , and bronchoscopy . Function was assessed by PaO2/FIO2 ratio , extravascular lung water index ( EVLWI ) , and pulmonary vascular resistance ( PVR ) . A nontrial group of 122 donors ( 244 lungs ) received similar management without bronchoscopy , pulmonary artery flotation catheter monitoring , or lung water assessment . RESULTS 
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In the face of these results , administering or withholding steroids both appear reasonable courses of action