Abstract

BACKGROUND To develop a risk prediction model for the occurrence of severe acute kidney injury (AKI) in intensive care unit (ICU) patients receiving fluid resuscitation. METHODS We conducted a secondary analysis of the Crystalloid vs. Hydroxyethyl Starch Trial (CHEST) trial, a blinded randomized controlled trial that enrolled ICU patients who received intravenous fluid resuscitation. The primary outcome was the first event in a composite outcome of doubling of serum creatinine and/or treatment with renal replacement treatment (RRT) within 28 days of randomization. The final model developed using multivariable logistic regression with backwards elimination was validated internally and then translated into a predictive equation. RESULTS Six thousand seven hundred twenty-seven ICU participants were studied, among whom 745 developed the study outcome. The final model having six variables, including admission diagnosis of sepsis, illness severity score, mechanical ventilation, tachycardia, baseline estimated glomerular filtration rate and emergency admission. The model had good discrimination (c-statistic = 0.72, 95% confidence interval 0.697-0.736) and calibration (Hosmer-Lemeshow test, χ(2) = 14.4, p = 0.07) for the composite outcome, with a c-statistic after internal bootstrapping validation of 0.72, which revealed a low degree of over-fitting. The positive predictive value and negative predictive value were 58.8 and 89.1%, respectively. The decision curve analysis indicates a net benefit in prediction of severe AKI using the model across a range of threshold probabilities between 5 and 35%. CONCLUSIONS Our model, using readily available clinical variables to identify ICU patients at high risk of severe AKI achieved good predictive performance in a clinically relevant population.

Abstract

OBJECTIVES Saline and Plasma-Lyte have different physiochemical contents; consequently, they may differently affect patients' renal function. We compared the effects of fluid therapy with 0.9% saline and with Plasma-Lyte 148 on renal function as assessed by creatinine concentration among patients undergoing major surgery. METHODS We conducted a prospective, double-blinded cluster crossover trial comparing the effects of the two fluids on major surgery patients. The primary aim was to establish the pilot feasibility, safety and preliminary efficacy evidence base for a large interventional trial to establish whether saline or Plasma-Lyte is the preferred crystalloid fluid for managing major surgery patients. The primary efficacy outcome was the proportion of patients with changes in renal function as assessed by creatinine concentration during their index hospital admission. We used changes in creatinine to define acute kidney injury (AKI) according to the RIFLE criteria. RESULTS The study was feasible with 100% patient and clinician acceptance. There were no deviations from the trial protocol. After screening, we allocated 602 patients to saline and 458 to Plasma-Lyte. The median (IQR) volume of intraoperative fluid received was 2000 mL (1000:2000) in both groups. Forty-nine saline patients (8.1%) and 49 Plasma-Lyte patients (10.7%) developed a postoperative AKI (adjusted incidence rate ratio [aIRR]: 1.34; 95% CI: 0.93-1.95; p = 0.120). No differences were observed in the development of postoperative complications (aIRR: 0.98; 95% CI: 0.89-1.08) or the severity of the worst complication (aIRR: 1.00; 95% CI: 0.78-1.30). The median (IQR) length of hospital stay was six days (3:11) for the saline group and five days (3:10) for the Plasma-Lyte group (aIRR: 0.85; 95% CI: 0.73-0.98). There were no serious adverse events relating to the trial fluids, nor were there fluid crossover or contamination events. CONCLUSIONS The study design was feasible to support a future follow-up larger clinical trial. Patients treated with saline did not demonstrate an increased incidence of postoperative AKI (defined as changes in creatinine) compared to those treated with Plasma-Lyte. Our findings imply that clinicians can reasonably use either solution intraoperatively for adult patients undergoing major surgery. TRIAL REGISTRATION Registry: Australian New Zealand Clinical Trials Registry; ACTRN12613001042730; URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=364988.

Abstract

AIM: The aim of this study was to investigate the association of hyperoncotic (20%) human albumin solution (HAS) with outcomes among critically ill patients receiving continuous renal replacement therapy (RRT). METHODS Analysis of the Randomized Evaluation of Normal versus Augmented Level (RENAL) RRT trial data. RESULTS Of 1,508 patients, 771 (51%) received albumin. Of these, 345 (45%) received 4% HAS only, 155 (20%) received 20% HAS only, and 271 (35%) received both. Patients who received combined 4% and 20% HAS were more severely ill, received more days of RENAL trial therapy and required mechanical ventilation for longer. Mean daily fluid balance was -288 mL (-904 to 261) with 20% HAS only versus 245 mL (-248 to 1,050) with 4% HAS only (p < 0.001). On Cox proportional hazards regression, 20% HAS exposure was not associated with greater 90-day mortality (odds ratio 1.12, 95% confidence interval [CI]: 0.77-1.62; p = 0.55) or longer recovery to RRT independence (sub-hazard ratio 1.04, 95% CI: 0.84-1.30; p = 0.70) compared to those who received 4% HAS only. CONCLUSIONS RENAL trial patients commonly received albumin in varying concentrations. The administration of 20% HAS was associated with a more negative fluid balance but was not independently associated with increased mortality or RRT dependence when compared to 4% HAS only.

Abstract

OBJECTIVES Mannitol and hypertonic saline are used to treat raised intracerebral pressure in patients with traumatic brain injury, but their possible effects on kidney function and mortality are unknown. DESIGN A post hoc analysis of the erythropoietin trial in traumatic brain injury (ClinicalTrials.gov NCT00987454) including daily data on mannitol and hypertonic saline use. SETTING Twenty-nine university-affiliated teaching hospitals in seven countries. PATIENTS A total of 568 patients treated in the ICU for 48 hours without acute kidney injury of whom 43 (7%) received mannitol and 170 (29%) hypertonic saline. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS We categorized acute kidney injury stage according to the Kidney Disease Improving Global Outcome classification and defined acute kidney injury as any Kidney Disease Improving Global Outcome stage-based changes from the admission creatinine. We tested associations between early (first 2 d) mannitol and hypertonic saline and time to acute kidney injury up to ICU discharge and death up to 180 days with Cox regression analysis. Subsequently, acute kidney injury developed more often in patients receiving mannitol (35% vs 10%; p < 0.001) and hypertonic saline (23% vs 10%; p < 0.001). On competing risk analysis including factors associated with acute kidney injury, mannitol (hazard ratio, 2.3; 95% CI, 1.2-4.3; p = 0.01), but not hypertonic saline (hazard ratio, 1.6; 95% CI, 0.9-2.8; p = 0.08), was independently associated with time to acute kidney injury. In a Cox model for predicting time to death, both the use of mannitol (hazard ratio, 2.1; 95% CI, 1.1-4.1; p = 0.03) and hypertonic saline (hazard ratio, 1.8; 95% CI, 1.02-3.2; p = 0.04) were associated with time to death. CONCLUSIONS In this post hoc analysis of a randomized controlled trial, the early use of mannitol, but not hypertonic saline, was independently associated with an increase in acute kidney injury. Our findings suggest the need to further evaluate the use and choice of osmotherapy in traumatic brain injury.

Abstract

AIMS: To study the impact of early human albumin solution (HAS) in continuous renal replacement therapy (RRT) patients. METHODS Analysis of Randomized Evaluation of Normal versus Augmented Level (RENAL) RRT trial data. RESULTS Of 1,464 patients, 500 (34%) received early albumin. These patients had higher illness severity scores, greater use of mechanical ventilation, and 90-day mortality (51 vs. 41%; p < 0.001). However, early albumin carried similar RRT dependence risk among survivors at day 90 (4.9 vs. 5.8%; p = 0.62). On Cox proportional hazards regression, with standardized inverse probability of treatment weighting, early albumin was not associated with increased mortality (hazard ratio [HR]: 1.23, 95% CI: 0.97-1.55; p = 0.09) or recovery to RRT independence (HR: 0.92, 95% CI: 0.78-1.10; p = 0.38). CONCLUSIONS Early albumin was administered to one-third of RENAL trial patients and in those with greater illness severity. Early albumin was not independently associated with mortality risk or rate of recovery to RRT independence.

Abstract

OBJECTIVES Trials comparing the effects of transfusing RBC units of different storage durations have considered mortality or morbidity as outcomes. We perform the first economic evaluation alongside a full age of blood clinical trial with a large population assessing the impact of RBC storage duration on quality-of-life and costs in critically ill adults. DESIGN Quality-of-life was measured at 6 months post randomization using the EuroQol 5-dimension 3-level instrument. The economic evaluation considers quality-adjusted life year and cost implications from randomization to 6 months. A generalized linear model was used to estimate incremental costs (2016 U.S. dollars) and quality-adjusted life years, respectively while adjusting for baseline characteristics. SETTING Fifty-nine ICUs in five countries. PATIENTS Adults with an anticipated ICU stay of at least 24 hours when the decision had been made to transfuse at least one RBC unit. INTERVENTIONS Patients were randomized to receive either the freshest or oldest available compatible RBC units (standard practice) in the hospital transfusion service. MEASUREMENTS AND MAIN RESULTS EuroQol 5-dimension 3-level utility scores were similar at 6 months-0.65 in the short-term and 0.63 in the long-term storage group (difference, 0.02; 95% CI, -0.00 to 0.04; p = 0.10). There were no significant differences in resource use between the two groups apart from 3.0 fewer hospital readmission days (95% CI, -5.3 to -0.8; p = 0.01) during follow-up in the short-term storage group. There were no significant differences in adjusted total costs or quality-adjusted life years between the short- and long-term storage groups (incremental costs, -$2,358; 95% CI, -$5,586 to $711) and incremental quality-adjusted life years: 0.003 quality-adjusted life years (95% CI, -0.003 to 0.008). CONCLUSIONS Without considering the additional supply cost of implementing a freshest available RBC strategy for critical care patients, there is no evidence to suggest that the policy improves quality-of-life or reduces other costs compared with standard transfusion practice.

Abstract

BACKGROUND Cryopreservation extends platelet (PLT) shelf life from 5 to 7 days to 2 to 4 years. However, only 73 patients have been transfused cryopreserved PLTs in published randomized controlled trials (RCTs), making safety data insufficient for regulatory approval. STUDY DESIGN AND METHODS The Cryopreserved vs. Liquid Platelet (CLIP) study was a double-blind, pilot, multicenter RCT involving high-risk cardiothoracic surgical patients in four Australian hospitals. The objective was to test, as the primary outcome, the feasibility and safety of the protocol. Patients were allocated to study group by permuted block randomization, with patients and clinicians blinded by use of an opaque shroud placed over each study PLT unit. Up to 3 units of cryopreserved or liquid-stored PLTs were administered per patient. No other aspect of patient care was affected. Adverse events were actively sought. RESULTS A total of 121 patients were randomized, of whom 23 received cryopreserved PLTs and 18 received liquid-stored PLTs. There were no differences in blood loss (median, 715 mL vs. 805 mL at 24 hr; difference between groups 90 mL [95% CI, -343.8 to 163.8 mL], p = 0.41), but the Bleeding Academic Research Consortium criterion for significant postoperative hemorrhage in cardiac surgery composite bleeding endpoint occurred in nearly twice as many patients in the liquid-stored group (55.6% vs. 30.4%, p = 0.10). Red blood cell transfusion requirements were a median of 3 units in the cryopreserved group versus 4 units with liquid-stored PLTs (difference between groups, 1 unit [95% CI, -3.1 to 1.1 units]; p = 0.23). Patients in the cryopreserved group were more likely to be transfused fresh-frozen plasma (78.3% vs. 27.8%, p = 0.002) and received more study PLT units (median, 2 units vs. 1 unit; difference between groups, 1 unit [95% CI, -0.03 to 2.0 units]; p = 0.012). There were no between-group differences in potential harms including deep venous thrombosis, myocardial infarction, respiratory function, infection, and renal function. No patient had died at 28 days, and postoperative length of stay was similar in each group. CONCLUSION In this pilot RCT, compared to liquid-stored PLTs, cryopreserved PLTs were associated with no evidence of harm. A definitive study testing safety and hemostatic effectiveness is warranted.

Abstract

PURPOSE To determine if a regimen of restricted fluids and early vasopressor compared to usual care is feasible for initial resuscitation of hypotension due to suspected sepsis. METHODS A prospective, randomised, open-label, clinical trial of a restricted fluid resuscitation regimen in the first 6 h among patients in the emergency department (ED) with suspected sepsis and a systolic blood pressure under 100 mmHg, after minimum 1000 ml of IV fluid. Primary outcome was total fluid administered within 6 h post randomisation. RESULTS There were 99 participants (50 restricted volume and 49 usual care) in the intention-to-treat analysis. Median volume from presentation to 6 h in the restricted volume group was 2387 ml [first to third quartile (Q1-Q3) 1750-2750 ml]; 30 ml/kg (Q1-Q3 32-39 ml/kg) vs. 3000 ml (Q1-Q3 2250-3900 ml); 43 ml/kg (Q1-Q3 35-50 ml/kg) in the usual care group (p < 0.001). Median duration of vasopressor support was 21 h (Q1-Q3 9-42 h) vs. 33 h (Q1-Q3 15-50 h), (p = 0.13) in the restricted volume and usual care groups, respectively. At 90-days, 4 of 48 (8%) in the restricted volume group and 3 of 47 (6%) in the usual care group had died. Protocol deviations occurred in 6/50 (12%) in restricted group and 11/49 (22%) in the usual care group, and serious adverse events in four cases (8%) in each group. CONCLUSIONS A regimen of restricted fluids and early vasopressor in ED patients with suspected sepsis and hypotension appears feasible. Illness severity was moderate and mortality rates low. A future trial is necessary with recruitment of high-risk patients to determine effects on clinical outcomes in this setting.

Abstract

PURPOSE We set out to assess the resuscitation fluid requirements and physiological and clinical responses of intensive care unit (ICU) patients resuscitated with 20% albumin versus 4-5% albumin. METHODS We performed a randomised controlled trial in 321 adult patients requiring fluid resuscitation within 48 h of admission to three ICUs in Australia and the UK. RESULTS The cumulative volume of resuscitation fluid at 48 h (primary outcome) was lower in the 20% albumin group than in the 4-5% albumin group [median difference - 600 ml, 95% confidence interval (CI) - 800 to - 400; P < 0.001]. The 20% albumin group had lower cumulative fluid balance at 48 h (mean difference - 576 ml, 95% CI - 1033 to - 119; P = 0.01). Peak albumin levels were higher but sodium and chloride levels lower in the 20% albumin group. Median (interquartile range) duration of mechanical ventilation was 12.0 h (7.6, 33.1) in the 20% albumin group and 15.3 h (7.7, 58.1) in the 4-5% albumin group (P = 0.13); the proportion of patients commenced on renal replacement therapy after randomization was 3.3% and 4.2% (P = 0.67), respectively, and the proportion discharged alive from ICU was 97.4% and 91.1% (P = 0.02). CONCLUSIONS Resuscitation with 20% albumin decreased resuscitation fluid requirements, minimized positive early fluid balance and was not associated with any evidence of harm compared with 4-5% albumin. These findings support the safety of further exploration of resuscitation with 20% albumin in larger randomised trials. TRIAL REGISTRATION http://www.anzctr.org.au . Identifier ACTRN12615000349549.

Abstract

OBJECTIVE To evaluate the effect of Plasma-Lyte 148 (PL-148) compared with 0.9% saline (saline) on blood product use and postoperative bleeding in patients admitted to the intensive care unit (ICU) following cardiac surgery. DESIGN A post hoc subgroup analysis conducted within a multicenter, double-blind, cluster-randomized, double-crossover study (study 1) and a prospective, single-center nested-cohort study (study 2). SETTING Tertiary-care hospitals. PARTICIPANTS Adults admitted to the ICU after cardiac surgery requiring crystalloid fluid therapy as part of the 0.9% saline vs. PL-148 for ICU fluid therapy (SPLIT) trial. INTERVENTIONS Blinded saline or PL-148 for 4 alternating 7-week blocks. MEASUREMENTS AND MAIN RESULTS 954 patients were included in study 1; 475 patients received PL-148, and 479 received saline. 128 of 475 patients (26.9%) in the PL-148 group received blood or a blood product compared with 94 of 479 patients (19.6%) in the saline group (OR [95% confidence interval], 1.51 [1.11-2.05]; p = 0.008). In study 2, 131 patients were allocated to PL-148 and 120 patients were allocated to saline. There were no differences between groups in chest drain output from the time of arrival in the ICU until 12 hours postoperatively (geometric mean, 566 mL for the PL-148 group v 547 mL in the saline group; p = 0.60). CONCLUSIONS The findings did not support the hypothesis that using PL-148 for fluid therapy in ICU following cardiac surgery reduces transfusion requirements compared to saline. The significantly increased proportion of patients receiving blood or blood product with allocation to PL-148 compared to saline was unexpected and requires verification through further research.