Determining the optimal time for liberation from renal replacement therapy in critically ill patients: protocol for a systematic review and meta-analysis (DOnE RRT)

INTRODUCTION

Renal replacement therapy (RRT) is a complex and expensive form of life-sustaining therapy, reserved for our most acutely ill patients. While a number of randomised trials have evaluated the optimal timing to start RRT among critically ill patients in the intensive care unit (ICU), there has been a paucity of trials providing guidance on when and under what circumstances to ideally liberate a patient from RRT. We are conducting a systematic review and meta-analysis to identify clinical and biochemical markers that predict kidney recovery and successful liberation from acute RRT among critically ill patients with acute kidney injury.

METHODS AND ANALYSIS

Our comprehensive search strategy was developed in consultation with a research librarian and independently peer-reviewed by a second librarian. We will search electronic databases: Ovid Medline, Ovid Embase and Wiley Cochrane Library. Selected grey literature sources will also be searched. Our search strategies will focus on concepts related to RRT (ie, intermittent haemodialysis, slow low-efficiency dialysis, continuous renal replacement therapy), intensive care (ie, involving any ICU setting) and discontinuation of therapy (ie, either clinical, physiological and biochemical parameters of weaning acute RRT) from 1990 to October 10, 2017. Citation screening, selection, quality assessment and data abstraction will be performed in duplicate. Studies will, where possible, be pooled in statistical meta-analysis. When deemed sufficiently clinically homogenous, and we have four or more studies reporting, sensitivities and specificities will be pooled simultaneously using a hierarchical summary receiver operator characteristic curve and bivariate analysis.

ETHICS AND DISSEMINATION

Our systematic review will synthesise the literature on clinical and biochemical markers that predict liberation from RRT. Research ethics approval is not required.

TRIAL REGISTRATION NUMBER

CRD42018074615.

Polymyxin B hemoperfusion in endotoxemic septic shock patients without extreme endotoxemia: a post hoc analysis of the EUPHRATES trial

PURPOSE

The EUPHRATES trial examined the impact of polymyxin B hemoperfusion (PMX) on mortality in patients with septic shock and endotoxemia, defined as EAA ≥ 0.60. No difference was found in 28-day all-cause mortality. However, the trial showed that in some patients with septic shock the burden of endotoxin activity was extreme (EAA ≥ 0.9). In a post hoc analysis, we evaluated the impact of PMX use in patients with septic shock and endotoxin activity measured between 0.6-0.89.

METHODS

Post-hoc analysis of the EUPHRATES trial for the 194 patients with EAA ≥ 0.6-0.89 who completed two treatments (PMX or sham). The primary end point was mortality at 28 days adjusted for APACHE II score and baseline mean arterial pressure (MAP). Additional end points included changes in MAP, cumulative vasopressor index (CVI), median EAA reduction, ventilator-free days (VFD), dialysis-free days (DFD) and hospital length of stay. Subpopulations analyzed were site and type of infection and those with norepinephrine dose > 0.1 mcg/kg/min at baseline.

RESULTS

At 28 days, 23 patients of 88 (26.1%) in the PMX group died versus 39 of 106 (36.8%) in the sham group [risk difference 10.7%, OR 0.52, 95% CI (0.27, 0.99), P = 0.047]. When unadjusted for baseline variables, P = 0.11. The 28-day survival time in the PMX group was longer than for the sham group [HR 0.56 (95% CI 0.33, 0.95) P = 0.03]. PMX treatment compared with sham showed greater change in MAP [median (IQR) 8 mmHg (- 0.5, 19.5) vs. 4 mmHg (- 4.0, 11) P = 0.04] and VFD [median (IQR) 20 days (0.5, 23.5) vs. 6 days (0, 20), P = 0.004]. There were no significant differences in other end points. There was a significant difference in mortality in PMX-treated patients with no bacterial growth on culture [PMX, 6/30 (20%) vs. sham, 13/31 (41.9%), P = 0.005]. The median EAA change in the population was - 12.9% (range: increase 49.2%-reduction 86.3%). The mortality in the above median EAA change group was PMX: 6/38 (15.7%) vs. sham 15/49 (30.6%), P = 0.08.

CONCLUSIONS

These hypothesis-generating results, based on an exploratory post hoc analysis of the EUPHRATES trial, suggest measurable responses in patients with septic shock and an EAA ≥ 0.6 to 0.89 on changes in mean arterial pressure, ventilator-free days and mortality.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT01046669. Funding Spectral Medical Incorporated.

Acute Management of Diabetic Ketoacidosis in Adults at 3 Teaching Hospitals in Canada: A Multicentre, Retrospective Cohort Study

OBJECTIVES

Diabetic ketoacidosis (DKA) is a common acute complication of diabetes mellitus and is associated with significant morbidity and mortality. There is currently a paucity of data concerning the Canadian experience with DKA. We aimed to characterize the acute management and course of DKA at several Canadian hospitals.

METHODS

We performed a retrospective cohort study of patients admitted to 3 teaching hospitals in Edmonton, Canada. We extracted clinical and laboratory data from the medical charts of patients admitted to general internal medicine wards or intensive care units with moderate or severe DKA.

RESULTS

We included 103 admissions (84 patients) in our study. The majority (68.9%) had type 1 diabetes and presented with severe DKA (60.2%). In the first 24 h, the median (interquartile range) intravenous fluid received was 7.0 (5.5 to 8.8) litres; 23.3% received a priming insulin bolus, 24.3% received bicarbonate and 91.3% received potassium. Hypoglycemia was relatively rare (5.8%), but hypokalemia was common (41.7%). The median time to anion gap ≤12 mmol/L was 8.8 (6.0 to 12.3) h. In 27.1% of cases, intravenous insulin was stopped prior to subcutaneous insulin administration, with a median of 95 (30 to 310) min elapsing before subcutaneous insulin was given. DKA-related mortality was 2.9%.

CONCLUSIONS

The acute management of DKA was generally aligned with clinical guidelines. Areas for improvement include preventing hypokalemia by proactively increasing potassium repletion, reducing initial insulin boluses, administering subcutaneous insulin before stopping intravenous insulin and administering sodium bicarbonate judiciously. Protocols and preprinted order sets may be helpful, especially in smaller centres.

Caloric intake and the fat-to-carbohydrate ratio in hypercapnic acute respiratory failure: Post-hoc analysis of the PermiT trial

BACKGROUND

The effect of moderate caloric enteral intake in critically ill patients with hypercapnic acute respiratory failure (HCARF) is unclear. We studied the impact of permissive underfeeding (PUF) compared with standard feeding (SF) on various HCARF outcomes.

MATERIALS AND METHODS

The PermiT trial randomized 894 patients to either PUF (40-60% caloric requirement) or SF (70-100% requirement) with similar protein intake and found no difference in mortality, mechanical ventilation (MV) duration and ventilator-free days. In this post-hoc study, we restricted analysis to mechanically-ventilated patients with HCARF (PaCO₂ >45 mmHg on the first two study days) and assessed the impact of trial interventions and fat-to-carbohydrate ratio on outcomes.

RESULTS

One-hundred-twenty patients had HCARF (59 PUF and 61 SF, age 53.7 ± 17.8 years, body mass index 31.1 ± 11.2 kg/m², Acute Physiology and Chronic Health Evaluation II score 21.7 ± 7.1 and day-1 PaCO₂ 61 ± 16 mmHg). Caloric intake was 815 ± 270 kcal/day in PUF group and 1289 ± 407 kcal/day in SF group. The two groups had similar PaCO₂ levels during ICU stay. The 90-day mortality (33.9% versus 35.6%, p = 0.85), MV duration (10.7 ± 6.8 versus 11.1 ± 8.1 days, p = 0.56) and ventilator-free days (52.9 ± 38.6 versus 51.2 ± 38.0 days, p = 0.80) were also similar in PUF and SF groups, respectively. Ventilator-free days and 90-day mortality were similar when the fat-to-carbohydrate ratio was < or ≥ the median value (0.73) in all patients and in PUF and SF groups.

CONCLUSIONS

In patients with HCARF, SF and PUF were associated with similar PaCO₂, MV duration, ventilator-free days and mortality. Fat-to-carbohydrate ratio was not associated with mortality or ventilator-free days.

TRIAL REGISTRATION

ISRCTN Registry: ISRCTN68144998.

Association of protein intake with the outcomes of critically ill patients: a post hoc analysis of the PermiT trial

Background

The optimal amount of protein intake in critically ill patients is uncertain.

Objective

In this post hoc analysis of the PermiT (Permissive Underfeeding vs. Target Enteral Feeding in Adult Critically Ill Patients) trial, we tested the hypothesis that higher total protein intake was associated with lower 90-d mortality and improved protein biomarkers in critically ill patients.

Design

In this post hoc analysis of the PermiT trial, we included patients who received enteral feeding for ≥3 consecutive days. Using the median protein intake of the cohort as a cutoff, patients were categorized into 2 groups: a higher-protein group (>0.80 g · kg-1 · d-1) and a lower-protein group (≤0.80 g · kg-1 · d-1). We developed a propensity score for receiving higher protein. Primary outcome was 90-d mortality. We also compared serial values of prealbumin, transferrin, 24-h urinary nitrogen, and 24-h nitrogen balance on days 1, 7, and 14.

Results

Among the 729 patients included in this analysis, the average protein intake was 0.8 ± 0.3 g · kg-1 · d-1 [1.0 ± 0.2 g · kg-1 · d-1 in the higher-protein group (n = 365) and 0.6 ± 0.2 g · kg-1 · d-1 in the lower-protein group (n = 364); P < 0.0001]. There was no difference in 90-d mortality between the 2 groups [88/364 (24.2%) compared with 94/363 (25.9%), propensity score-adjusted OR: 0.80; 95% CI: 0.56, 1.16; P = 0.24]. Higher protein intake was associated with an increase in 24-h urea nitrogen excretion compared with lower protein intake, but without a significant change in prealbumin, transferrin, or 24-h nitrogen balance.

Conclusions

In the PermiT trial, a moderate difference in protein intake was not associated with lower mortality. Higher protein intake was associated with increased nitrogen excretion in the urine without a corresponding change in prealbumin, transferrin, or nitrogen balance. Protein intake needs to be tested in adequately powered randomized controlled trials targeting larger differences in protein intake in high-risk populations.

Effect of Targeted Polymyxin B Hemoperfusion on 28-Day Mortality in Patients With Septic Shock and Elevated Endotoxin Level: The EUPHRATES Randomized Clinical Trial

Importance

Polymyxin B hemoperfusion reduces blood endotoxin levels in sepsis. Endotoxin activity can be measured in blood with a rapid assay. Treating patients with septic shock and elevated endotoxin activity using polymyxin B hemoperfusion may improve clinical outcomes.

Objective

To test whether adding polymyxin B hemoperfusion to conventional medical therapy improves survival compared with conventional therapy alone among patients with septic shock and high endotoxin activity.

Design, Setting, and Participants

Multicenter, randomized clinical trial involving 450 adult critically ill patients with septic shock and an endotoxin activity assay level of 0.60 or higher enrolled between September 2010 and June 2016 at 55 tertiary hospitals in North America. Last follow-up was June 2017.

Interventions

Two polymyxin B hemoperfusion treatments (90-120 minutes) plus standard therapy completed within 24 hours of enrollment (n = 224 patients) or sham hemoperfusion plus standard therapy (n = 226 patients).

Main Outcomes and Measures

The primary outcome was mortality at 28 days among all patients randomized (all participants) and among patients randomized with a multiple organ dysfunction score (MODS) of more than 9.

Results

Among 450 eligible enrolled patients (mean age, 59.8 years; 177 [39.3%] women; mean APACHE II score 29.4 [range, 0-71 with higher scores indicating greater severity), 449 (99.8%) completed the study. Polymyxin B hemoperfusion was not associated with a significant difference in mortality at 28 days among all participants (treatment group, 84 of 223 [37.7%] vs sham group 78 of 226 [34.5%]; risk difference [RD], 3.2%; 95% CI, -5.7% to 12.0%; relative risk [RR], 1.09; 95% CI, 0.85-1.39; P = .49) or in the population with a MODS of more than 9 (treatment group, 65 of 146 [44.5%] vs sham, 65 of 148 [43.9%]; RD, 0.6%; 95% CI, -10.8% to 11.9%; RR, 1.01; 95% CI, 0.78-1.31; P = .92). Overall, 264 serious adverse events were reported (65.1% treatment group vs 57.3% sham group). The most frequent serious adverse events were worsening of sepsis (10.8% treatment group vs 9.1% sham group) and worsening of septic shock (6.6% treatment group vs 7.7% sham group).

Conclusions and Relevance

Among patients with septic shock and high endotoxin activity, polymyxin B hemoperfusion treatment plus conventional medical therapy compared with sham treatment plus conventional medical therapy did not reduce mortality at 28 days.

Trial Registration

ClinicalTrials.gov Identifier: NCT01046669.

Assessment of the Safety of Discharging Select Patients Directly Home From the Intensive Care Unit: A Multicenter Population-Based Cohort Study

IMPORTANCE

The safety of discharging adult patients recovering from critical illness directly home from the intensive care unit (ICU) is unknown.

OBJECTIVE

To compare the health care utilization and clinical outcomes for ICU patients discharged directly home from the ICU with those of patients discharged home via the hospital ward.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective population-based cohort study of adult patients admitted to the ICU of 9 medical-surgical hospitals from January 1, 2014, to January 1, 2016, with 1-year follow-up after hospital discharge. All adult ICU patients were discharged home alive from hospital, and the propensity score matched cohort (1:1) was based on patient characteristics, therapies received in the ICU, and hospital characteristics.

EXPOSURES

Patient disposition on discharge from the ICU: directly home vs home via the hospital ward.

MAIN OUTCOMES AND MEASURES

The primary outcome was readmission to the hospital within 30 days of hospital discharge. The secondary outcomes were emergency department visit within 30 days and death within 1 year.

RESULTS

Among the 6732 patients included in the study, 2826 (42%) were female; median age, 56 years (interquartile range, 41-67 years); 922 (14%) were discharged directly home, with significant variation found between hospitals (range, 4.4%-44.0%). Compared with patients discharged home via the hospital ward, patients discharged directly home were younger (median age 47 vs 57 years; P < .001), more likely to be admitted with a diagnosis of overdose, substance withdrawal, seizures, or metabolic coma (32% [295] vs 10% [594]; P < .001), to have a lower severity of acute illness on ICU admission (median APACHE II score 15 vs 18; P < .001), and receive less than 48 hours of invasive mechanical ventilation (42% [389] vs 34% [1984]; P < .001). In the propensity score matched cohort (n = 1632), patients discharged directly home had similar length of ICU stay (median, 3.1 days vs 3.0 days; P = .42) but significantly shorter length of hospital stay (median, 3.3 days vs 9.2 days; P < .001) compared with patients discharged home via the hospital ward. There were no significant differences between patients discharged directly home or home via the hospital ward for readmission to the hospital (10% [n = 81] vs 11% [n = 92]; hazard ratio [HR], 0.88; 95% CI, 0.64-1.20) or emergency department visit (25% [n = 200] vs 26% [n = 212]; HR, 0.94; 95% CI, 0.81-1.09) within 30 days of hospital discharge. Four percent of patients in both groups died within 1 year of hospital discharge (n = 31 and n = 34 in the discharged directly home and discharged home via the hospital ward groups, respectively) (HR, 0.90; 95% CI, 0.60-1.35).

CONCLUSIONS AND RELEVANCE

The discharge of select adult patients directly home from the ICU is common, and it is not associated with increased health care utilization or increased mortality.

Six-Month Outcomes after Restrictive or Liberal Transfusion for Cardiac Surgery

BACKGROUND

We reported previously that, in patients undergoing cardiac surgery who were at moderate-to-high risk for death, a restrictive transfusion strategy was noninferior to a liberal strategy with respect to the composite outcome of death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis by hospital discharge or 28 days after surgery, whichever came first. We now report the clinical outcomes at 6 months after surgery.

METHODS

We randomly assigned 5243 adults undergoing cardiac surgery to a restrictive red-cell transfusion strategy (transfusion if the hemoglobin concentration was <7.5 g per deciliter intraoperatively or postoperatively) or a liberal red-cell transfusion strategy (transfusion if the hemoglobin concentration was <9.5 g per deciliter intraoperatively or postoperatively when the patient was in the intensive care unit [ICU] or was <8.5 g per deciliter when the patient was in the non-ICU ward). The primary composite outcome was death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis occurring within 6 months after the initial surgery. An expanded secondary composite outcome included all the components of the primary outcome as well as emergency department visit, hospital readmission, or coronary revascularization occurring within 6 months after the index surgery. The secondary outcomes included the individual components of the two composite outcomes.

RESULTS

At 6 months after surgery, the primary composite outcome had occurred in 402 of 2317 patients (17.4%) in the restrictive-threshold group and in 402 of 2347 patients (17.1%) in the liberal-threshold group (absolute risk difference before rounding, 0.22 percentage points; 95% confidence interval [CI], -1.95 to 2.39; odds ratio, 1.02; 95% CI, 0.87 to 1.18; P=0.006 for noninferiority). Mortality was 6.2% in the restrictive-threshold group and 6.4% in the liberal-threshold group (odds ratio, 0.95; 95% CI, 0.75 to 1.21). There were no significant between-group differences in the secondary outcomes.

CONCLUSIONS

In patients undergoing cardiac surgery who were at moderate-to-high risk for death, a restrictive strategy for red-cell transfusion was noninferior to a liberal strategy with respect to the composite outcome of death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis at 6 months after surgery. (Funded by the Canadian Institutes of Health Research and others; TRICS III ClinicalTrials.gov number, NCT02042898 .).

A cluster randomised, crossover, registry-embedded clinical trial of proton pump inhibitors versus histamine-2 receptor blockers for ulcer prophylaxis therapy in the intensive care unit (PEPTIC study): study protocol

BACKGROUND

The balance of risks and benefits with using proton pump inhibitors (PPIs) versus histamine-2 receptor blockers (H₂RB) for stress ulcer prophylaxis in patients who are invasively ventilated in the intensive care unit (ICU) is uncertain.

OBJECTIVE

To describe the study protocol and statistical analysis plan for the Proton Pump Inhibitors versus Histamine-2 Receptor Blockers for Ulcer Prophylaxis Therapy in the Intensive Care Unit (PEPTIC) study.

DESIGN, SETTING AND PARTICIPANTS

Protocol for a prospective, multicentre, randomised, open-label, cluster crossover, registry-embedded trial to be conducted in 50 ICUs in Australia, Canada, Ireland, New Zealand and the United Kingdom. The PEPTIC study will compare two approaches to stress ulcer prophylaxis in mechanically ventilated adults implemented at the level of the ICU. One approach is to use PPIs as the default therapy and the other approach is to use H2RBs as the default therapy when stress ulcer prophylaxis is prescribed. Each ICU, by random allocation, will use one approach for 6 months and will then switch to the opposite approach for the next 6 months. The PEPTIC study began recruitment in August 2016 and will complete recruitment in January 2019.

MAIN OUTCOME MEASURES

The primary end point will be in-hospital mortality. Secondary outcomes include clinically significant upper gastrointestinal bleeding, Clostridium difficile infection, ICU length of stay and hospital length of stay.

RESULTS AND CONCLUSIONS

The PEPTIC study will compare the effect on in-hospital mortality of implementing, at the level of the ICU, the use of PPI as the preferred agent for stress ulcer prophylaxis in mechanically ventilated adults in the ICU with using H₂RB as the preferred agent.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry (ANZCTRN 12616000481471).

Frailty and the Association Between Long-Term Recovery After Intensive Care Unit Admission

Frailty is common, although infrequently screened for among patients admitted to intensive care. Frailty has been the focus of research in geriatric medicine; however, its epidemiology and interaction with critical illness have only recently been studied. Instruments to screen for and measure frailty require refinement in intensive care settings. Frail critically ill patients are at higher risk of poor outcomes. Frail survivors of critical illness are high users of health resources. Further research is needed to understand how frailty assessment can inform decision-making before and during an episode of critical illness and during an intensive care course for frail patients.

Secondary EMR data for quality improvement and research: A comparison of manual and electronic data collection from an integrated critical care electronic medical record system

PURPOSE

This study measured the quality of data extracted from a clinical information system widely used for critical care quality improvement and research.

MATERIALS AND METHODS

We abstracted data from 30 fields in a random sample of 207 patients admitted to nine adult, medical-surgical intensive care units. We assessed concordance between data collected: (1) manually from the bedside system (eCritical MetaVision) by trained auditors, and (2) electronically from the system data warehouse (eCritical TRACER). Agreement was assessed using Cohen's Kappa for categorical variables and intraclass correlation coefficient (ICC) for continuous variables.

RESULTS

Concordance between data sets was excellent. There was perfect agreement for 11/30 variables (35%). The median Kappa score for the 16 categorical variables was 0.99 (IQR 0.92-1.00). APACHE II had an ICC of 0.936 (0.898-0.960). The lowest concordance was observed for SOFA renal and respiratory components (ICC 0.804 and 0.846, respectively). Score translation errors by the manual auditor were the most common source of data discrepancies.

CONCLUSIONS

Manual validation processes of electronic data are complex in comparison to validation of traditional clinical documentation. This study represents a straightforward approach to validate the use of data repositories to support reliable and efficient use of high quality secondary use data.

Indicators of intensive care unit capacity strain: a systematic review

BACKGROUND

Strained intensive care unit (ICU) capacity represents a fundamental supply-demand mismatch in ICU resources. Strain is likely to be influenced by a range of factors; however, there has been no systematic evaluation of the spectrum of measures that may indicate strain on ICU capacity.

METHODS

We performed a systematic review to identify indicators of strained capacity. A comprehensive peer-reviewed search of MEDLINE, EMBASE, CINAHL, Cochrane Library, and Web of Science Core Collection was performed along with selected grey literature sources. We included studies published in English after 1990. We included studies that: (1) focused on ICU settings; (2) included description of a quality or performance measure; and (3) described strained capacity. Retrieved studies were screened, selected and extracted in duplicate. Quality was assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS). Analysis was descriptive.

RESULTS

Of 5297 studies identified in our search; 51 fulfilled eligibility. Most were cohort studies (n = 39; 76.5%), five (9.8%) were case-control, three (5.8%) were cross-sectional, two (3.9%) were modeling studies, one (2%) was a correlational study, and one (2%) was a quality improvement project. Most observational studies were high quality. Sixteen measures designed to indicate strain were identified 110 times, and classified as structure (n = 4, 25%), process (n = 7, 44%) and outcome (n = 5, 31%) indicators, respectively. The most commonly identified indicators of strain were ICU acuity (n = 21; 19.1% [process]), ICU readmission (n = 18; 16.4% [outcome]), after-hours discharge (n = 15; 13.6% [process]) and ICU census (n = 13; 11.8% [structure]). There was substantial heterogeneity in the operational definitions used to define strain indicators across studies.

CONCLUSIONS

We identified and characterized 16 indicators of strained ICU capacity across the spectrum of healthcare quality domains. Future work should aim to evaluate their implementation into practice and assess their value for evaluating strategies to mitigate strain.

SYSTEMATIC REVIEW REGISTRATION

This systematic review was registered at PROSPERO (March 27, 2015; CRD42015017931 ).

Biomarkers for prediction of renal replacement therapy in acute kidney injury: a systematic review and meta-analysis

Purpose

Acute kidney injury (AKI) frequently occurs in critically ill patients and often precipitates use of renal replacement therapy (RRT). However, the ideal circumstances for whether and when to start RRT remain unclear. We performed evidence synthesis of the available literature to evaluate the value of biomarkers to predict receipt of RRT for AKI.

Methods

We conducted a PRISMA-guided systematic review and meta-analysis including all trials evaluating biomarker performance for prediction of RRT in AKI. A systematic search was applied in MEDLINE, Embase, and CENTRAL databases from inception to September 2017. All studies reporting an area under the curve (AUC) for a biomarker to predict initiation of RRT were included.

Results

Sixty-three studies comprising 15,928 critically ill patients (median per study 122.5 [31–1439]) met eligibility. Forty-one studies evaluating 13 different biomarkers were included. Of these biomarkers, neutrophil gelatinase-associated lipocalin (NGAL) had the largest body of evidence. The pooled AUCs for urine and blood NGAL were 0.720 (95% CI 0.638–0.803) and 0.755 (0.706–0.803), respectively. Blood creatinine and cystatin C had pooled AUCs of 0.764 (0.732–0.796) and 0.768 (0.729–0.807), respectively. For urine biomarkers, interleukin-18, cystatin C, and the product of tissue inhibitor of metalloproteinase-2 and insulin growth factor binding protein-7 showed pooled AUCs of 0.668 (0.606–0.729), 0.722 (0.575–0.868), and 0.857 (0.789–0.925), respectively.

Conclusion

Though several biomarkers showed promise and reasonable prediction of RRT use for critically ill patients with AKI, the strength of evidence currently precludes their routine use to guide decision-making on when to initiate RRT.

Electronic supplementary material

The online version of this article (10.1007/s00134-018-5126-8) contains supplementary material, which is available to authorized users.

Impact of nighttime Rapid Response Team activation on outcomes of hospitalized patients with acute deterioration

Background

Rapid Response Teams (RRTs) are groups of healthcare providers that are used by many hospitals to respond to acutely deteriorating patients admitted to the wards. We sought to identify outcomes of patients assessed by RRTs outside standard working hours.

Methods

We used a prospectively collected registry from two hospitals within a single tertiary care-level hospital system between May 1, 2012, and May 31, 2016. Patient information, outcomes, and RRT activation information were stored in the hospital data warehouse. Comparisons were made between RRT activation during daytime hours (0800–1659) and nighttime hours (1700–0759). The primary outcome was in-hospital mortality, analyzed using a multivariable logistic regression model.

Results

A total of 6023 RRT activations on discrete patients were analyzed, 3367 (55.9%) of which occurred during nighttime hours. Nighttime RRT activation was associated with increased odds of mortality, as compared with daytime RRT activation (adjusted OR 1.34, 95% CI 1.26–1.40, P = 0.02). The time periods associated with the highest odds of mortality were 0600–0700 (adjusted OR 1.30, 95% CI 1.09–1.61) and 2300–2400 (adjusted OR 1.34, 95% CI 1.01–1.56). Daytime RRT activation was associated with increased odds of intensive care unit admission (adjusted OR 1.40, 95% CI 1.31–1.50, P = 0.02). Time from onset of concerning symptoms to RRT activation was shorter among patients assessed during daytime hours (P < 0.001).

Conclusions

Acutely deteriorating ward patients assessed by an RRT at nighttime had a higher risk of in-hospital mortality. This work identifies important shortcomings in health service provision and quality of care outside daytime hours, highlighting an opportunity for quality improvement.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2005-1) contains supplementary material, which is available to authorized users.

Association Between Fluid Balance and Outcomes in Critically Ill Children: A Systematic Review and Meta-analysis

IMPORTANCE

After initial resuscitation, critically ill children may accumulate fluid and develop fluid overload. Accruing evidence suggests that fluid overload contributes to greater complexity of care and worse outcomes.

OBJECTIVE

To describe the methods to measure fluid balance, define fluid overload, and evaluate the association between fluid balance and outcomes in critically ill children.

DATA SOURCES

Systematic search of MEDLINE, EMBASE, Cochrane Library, trial registries, and selected gray literature from inception to March 2017.

STUDY SELECTION

Studies of children admitted to pediatric intensive care units that described fluid balance or fluid overload and reported outcomes of interest were included. No language restrictions were applied.

DATA EXTRACTION AND SYNTHESIS

All stages were conducted independently by 2 reviewers. Data extracted included study characteristics, population, fluid metrics, and outcomes. Risk of bias was assessed using the Newcastle-Ottawa Scale. Narrative description of fluid assessment methods and fluid overload definitions was done. When feasible, pooled analyses were performed using random-effects models.

MAIN OUTCOMES AND MEASURES

Mortality was the primary outcome. Secondary outcomes included treatment intensity, organ failure, and resource use.

RESULTS

A total of 44 studies (7507 children) were included in this systematic review and meta-analysis. Of those, 27 (61%) were retrospective cohort studies, 13 (30%) were prospective cohort studies, 3 (7%) were case-control studies, and 1 study (2%) was a secondary analysis of a randomized trial. The proportion of children with fluid overload varied by case mix and fluid overload definition (median, 33%; range, 10%-83%). Fluid overload, however defined, was associated with increased in-hospital mortality (17 studies [n = 2853]; odds ratio [OR], 4.34 [95% CI, 3.01-6.26]; I2 = 61%). Survivors had lower percentage fluid overload than nonsurvivors (22 studies [n = 2848]; mean difference, -5.62 [95% CI, -7.28 to -3.97]; I2 = 76%). After adjustment for illness severity, there was a 6% increase in odds of mortality for every 1% increase in percentage fluid overload (11 studies [n = 3200]; adjusted OR, 1.06 [95% CI, 1.03-1.10]; I2 = 66%). Fluid overload was associated with increased risk for prolonged mechanical ventilation (>48 hours) (3 studies [n = 631]; OR, 2.14 [95% CI, 1.25-3.66]; I2 = 0%) and acute kidney injury (7 studies [n = 1833]; OR, 2.36 [95% CI, 1.27-4.38]; I2 = 78%).

CONCLUSIONS AND RELEVANCE

Fluid overload is common and is associated with substantial morbidity and mortality in critically ill children. Additional research should now ideally focus on interventions aimed to mitigate the potential for harm associated with fluid overload.

Interventions to prevent hemodynamic instability during renal replacement therapy in critically ill patients: a systematic review

Background

Hemodynamic instability related to renal replacement therapy (HIRRT) may increase the risk of death and limit renal recovery. Studies in end-stage renal disease populations on maintenance hemodialysis suggest that some renal replacement therapy (RRT)-related interventions (e.g., cool dialysate) may reduce the occurrence of HIRRT, but less is known about interventions to prevent HIRRT in critically ill patients receiving RRT for acute kidney injury (AKI). We sought to evaluate the effectiveness of RRT-related interventions for reducing HIRRT in such patients across RRT modalities.

Methods

A systematic review of publications was undertaken using MEDLINE, MEDLINE in Process, EMBASE, and Cochrane’s Central Registry for Randomized Controlled Trials (RCTs). Studies that assessed any intervention’s effect on HIRRT (the primary outcome) in critically ill patients with AKI were included. HIRRT was variably defined according to each study’s definition. Two reviewers independently screened abstracts, identified articles for inclusion, extracted data, and evaluated study quality using validated assessment tools.

Results

Five RCTs and four observational studies were included (n = 9; 623 patients in total). Studies were small, and the quality was mostly low. Interventions included dialysate sodium modeling (n = 3), ultrafiltration profiling (n = 2), blood volume (n = 2) and temperature control (n = 3), duration of RRT (n = 1), and slow blood flow rate at initiation (n = 1). Some studies applied more than one strategy simultaneously (n = 5). Interventions shown to reduce HIRRT from three studies (two RCTs and one observational study) included higher dialysate sodium concentration, lower dialysate temperature, variable ultrafiltration rates, or a combination of strategies. Interventions not found to have an effect included blood volume and temperature control, extended duration of intermittent RRT, and slower blood flow rates during continuous RRT initiation. How HIRRT was defined and its frequency of occurrence varied widely across studies, including those involving the same RRT modality. Pooled analysis was not possible due to study heterogeneity.

Conclusions

Small clinical studies suggest that higher dialysate sodium, lower temperature, individualized ultrafiltration rates, or a combination of these strategies may reduce the risk of HIRRT. Overall, for all RRT modalities, there is a paucity of high-quality data regarding interventions to reduce the occurrence of HIRRT in critically ill patients.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-1965-5) contains supplementary material, which is available to authorized users.

7 versus 14 days of antibiotic treatment for critically ill patients with bloodstream infection: a pilot randomized clinical trial

Background

Shorter-duration antibiotic treatment is sufficient for a range of bacterial infections, but has not been adequately studied for bloodstream infections. Our systematic review, survey, and observational study indicated equipoise for a trial of 7 versus 14 days of antibiotic treatment for bloodstream infections; a pilot randomized clinical trial (RCT) was a necessary next step to assess feasibility of a larger trial.

Methods

We conducted an open, pilot RCT of antibiotic treatment duration among critically ill patients with bloodstream infection across 11 intensive care units (ICUs). Antibiotic selection, dosing and route were at the discretion of the treating team; patients were randomized 1:1 to intervention arms consisting of two fixed durations of treatment – 7 versus 14 days. We recruited adults with a positive blood culture yielding pathogenic bacteria identified while in ICU. We excluded patients with severe immunosuppression, foci of infection with an established requirement for prolonged treatment, single cultures with potential contaminants, or cultures yielding Staphylococcus aureus or fungi. The primary feasibility outcomes were recruitment rate and adherence to treatment duration protocol. Secondary outcomes included 90-day, ICU and hospital mortality, relapse of bacteremia, lengths of stay, mechanical ventilation and vasopressor duration, antibiotic-free days, Clostridium difficile, antibiotic adverse events, and secondary infection with antimicrobial-resistant organisms.

Results

We successfully achieved our target sample size (n = 115) and average recruitment rate of 1 (interquartile range (IQR) 0.3–1.5) patient/ICU/month. Adherence to treatment duration was achieved in 89/115 (77%) patients. Adherence differed by underlying source of infection: 26/31 (84%) lung; 18/29 (62%) intra-abdominal; 20/26 (77%) urinary tract; 8/9 (89%) vascular-catheter; 4/4 (100%) skin/soft tissue; 2/4 (50%) other; and 11/12 (92%) unknown sources. Patients experienced a median (IQR) 14 (8–17) antibiotic-free days (of the 28 days after blood culture collection). Antimicrobial-related adverse events included hepatitis in 1 (1%) patient, Clostridium difficile infection in 4 (4%), and secondary infection with highly resistant microorganisms in 10 (9%). Ascertainment was complete for all study outcomes in ICU, in hospital and at 90 days.

Conclusion

It is feasible to conduct a RCT to determine whether 7 versus 14 days of antibiotic treatment is associated with comparable 90-day survival.

Trial registration

ClinicalTrials.gov, identifier: NCT02261506. Registered on 26 September 2014.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2474-1) contains supplementary material, which is available to authorized users.

Transfers from intensive care unit to hospital ward: a multicentre textual analysis of physician progress notes

BACKGROUND

Little is known about documentation during transitions of patient care between clinical specialties. Therefore, we examined the focus, structure and purpose of physician progress notes for patients transferred from the intensive care unit (ICU) to hospital ward to identify opportunities to improve communication breaks.

METHODS

This was a prospective cohort study in ten Canadian hospitals. We analyzed physician progress notes for consenting adult patients transferred from a medical-surgical ICU to hospital ward. The number, length, legibility and content of notes was counted and compared across care settings using mixed-effects linear regression models accounting for clustering within hospitals. Qualitative content analyses were conducted on a stratified random sample of 32 patients.

RESULTS

A total of 447 patient medical records that included 7052 progress notes (mean 2.1 notes/patient/day 95% CI 1.9-2.3) were analyzed. Notes written by the ICU team were significantly longer than notes written by the ward team (mean lines of text 21 vs. 15, p < 0.001). There was a discrepancy between documentation of patient issues in the last ICU and first ward notes; mean agreement of patient issues was 42% [95% CI 31-53%]. Qualitative analyses identified eight themes related to focus (central point - e.g., problem list), structure (organization, - e.g., note-taking style), and purpose (intention - e.g., documentation of patient course) of the notes that varied across clinical specialties and physician seniority.

CONCLUSIONS

Important gaps and variations in written documentation during transitions of patient care between ICU and hospital ward physicians are common, and include discrepancies in documentation of patient information.

Acute Kidney Injury and Big Data

The recognition of a standardized, consensus definition for acute kidney injury (AKI) has been an important milestone in critical care nephrology, which has facilitated innovation in prevention, quality of care, and outcomes research among the growing population of hospitalized patients susceptible to AKI. Concomitantly, there have been substantial advances in "big data" technologies in medicine, including electronic health records (EHR), data registries and repositories, and data management and analytic methodologies. EHRs are increasingly being adopted, clinical informatics is constantly being refined, and the field of EHR-enabled care improvement and research has grown exponentially. While these fields have matured independently, integrating the two has the potential to redefine and integrate AKI-related care and research. AKI is an ideal condition to exploit big data health care innovation for several reasons: AKI is common, increasingly encountered in hospitalized settings, imposes meaningful risk for adverse events and poor outcomes, has incremental cost implications, and has been plagued by suboptimal quality of care. In this concise review, we discuss the potential applications of big data technologies, particularly modern EHR platforms and health data repositories, to transform our capacity for AKI prediction, detection, and care quality.

Correction to: Polymyxin B-immobilized hemoperfusion and mortality in critically ill adult patients with sepsis/septic shock: a systematic review with meta-analysis and trial sequential analysis

Owing to an oversight by the authors, Figure 2 in this article was not the version intended for publication. The correct Figure 2, reproduced here, features footnote symbols and Figure 2b includes three studies as described in the main text.

Risk of Acute Kidney Injury in Patients Randomized to a Restrictive Versus Liberal Approach to Red Blood Cell Transfusion in Cardiac Surgery: A Substudy Protocol of the Transfusion Requirements in Cardiac Surgery III Noninferiority Trial

Background:

When safe to do so, avoiding blood transfusions in cardiac surgery can avoid the risk of transfusion-related infections and other complications while protecting a scarce resource and reducing costs. This protocol describes a kidney substudy of the Transfusion Requirements in Cardiac Surgery III (TRICS-III) trial, a multinational noninferiority randomized controlled trial to determine whether the risk of major clinical outcomes in patients undergoing planned cardiac surgery with cardiopulmonary bypass is no greater with a restrictive versus liberal approach to red blood cell transfusion.

Objective:

The objective of this substudy is to determine whether the risk of acute kidney injury is no greater with a restrictive versus liberal approach to red blood cell transfusion, and whether this holds true in patients with and without preexisting chronic kidney disease.

Design and Setting:

Multinational noninferiority randomized controlled trial conducted in 73 centers in 19 countries (2014-2017).

Patients:

Patients (~4800) undergoing planned cardiac surgery with cardiopulmonary bypass.

Measurements:

The primary outcome of this substudy is perioperative acute kidney injury, defined as an acute rise in serum creatinine from the preoperative value (obtained in the 30-day period before surgery), where an acute rise is defined as ≥26.5 μmol/L in the first 48 hours after surgery or ≥50% in the first 7 days after surgery.

Methods:

We will report the absolute risk difference in acute kidney injury and the 95% confidence interval. We will repeat the primary analysis using alternative definitions of acute kidney injury, including staging definitions, and will examine effect modification by preexisting chronic kidney disease (defined as a preoperative estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m²).

Limitations:

It is not possible to blind patients or providers to the intervention; however, objective measures will be used to assess outcomes, and outcome assessors will be blinded to the intervention assignment.

Results:

Substudy results will be reported by the year 2018.

Conclusions:

This substudy will provide generalizable estimates of the risk of acute kidney injury of a restrictive versus liberal approach to red blood cell transfusion in the presence of anemia during cardiac surgery done with cardiopulmonary bypass.

Trial Registration:

www.clinicaltrials.gov; clinical trial registration number NCT 02042898.

Polymyxin B-immobilized hemoperfusion and mortality in critically ill adult patients with sepsis/septic shock: a systematic review with meta-analysis and trial sequential analysis

PURPOSE

Polymyxin B-immobilized hemoperfusion (PMX-HP) is an adjuvant therapy for sepsis or septic shock that clears circulating endotoxin. Prior trials have shown that PMX-HP improves surrogate endpoints. We aimed to conduct an evidence synthesis to evaluate the efficacy and safety of PMX-HP in critically ill adult patients with sepsis or septic shock.

METHODS

We searched for randomized controlled trials (RCTs) in MEDLINE, EMBASE, the Cochrane Library, the Health Technology Assessment Database, CINAHL, "Igaku Chuo Zasshi", the National Institute of Health Clinical Trials Register, the World Health Organization International Clinical Trials Registry Platform, the University Hospital Medical Information Network Clinical Trials Registry, the reference lists of retrieved articles, and publications by manufacturers of PMX-HP. The primary outcomes were 28-day all-cause mortality, the number of patients with at least one serious adverse event, and organ dysfunction scores. The GRADE methodology for the certainty of evidence was used.

RESULTS

Six trials (857 participants; weighted mean age 62.5 years) proved eligible. Patient-oriented primary outcomes were assessed. The pooled risk ratio (RR) for 28-day mortality associated with PMX-HP was 1.03 [95% confidence interval (CI) 0.78-1.36; I ² = 25%; n = 797]. The pooled RR for adverse events was 2.17 (95% CI 0.68-6.94; I ² = 0%; n = 717). Organ dysfunction scores over 24-72 h after PMX-HP treatment did not change significantly (standardized mean difference - 0.26; 95% CI - 0.64 to 0.12; I ² = 78%; n = 797). The certainty of the body of evidence was judged as low for both benefit and harm using the GRADE methodology.

CONCLUSIONS

There is currently insufficient evidence to support the routine use of PMX-HP to treat patients with sepsis or septic shock.

REGISTRATION

PROSPERO International Prospective Register of Systematic Reviews (CRD42016038356).

Incidence, correlates and outcomes associated with falls in the intensive care unit: a retrospective cohort study

BACKGROUND

Falls among hospitalised patients contribute to avoidable morbidity and prolonged hospital stay. We aimed to describe the incidence, circumstances and outcomes associated with patient falls occurring in intensive care units.

METHODS

Retrospective cohort study of adult admissions to an academic, tertiary ICU in Edmonton, Canada between 1 January 2013 and 30 April 2016. Fall events were ascertained by interrogation of an electronic health record. Each fall was independently adjudicated by two intensivists to confirm that a fall did occur, and to determine if the fall was potentially avoidable. Agreement was assessed by intraclass correlation (ICC). A matched cohort (one fall to five non-fall) was created to compare course and outcomes.

RESULTS

Of 31 events identified, 26 were adjudicated as a fall (84%), for an estimated incidence of 5.2 per 1000 ICU admissions (95% CI, 3.4-7.6). Of these, 23 were judged as avoidable (89%) (ICC, 0.69; 95% CI, 0.37-0.85). The mean age was 54.5 years (SD, 17.4 years), 20 of the falls (77%) involved men, and 10 (39%) were surgical admissions (eight [31%] for trauma). The median ICU stay before the falls was 10.6 days (interquartile range [IQR], 6.2-15.0 days), and 13 patients (50%) scored positive for delirium. At the time of the fall, three patients (12%) were invasively ventilated, and eight (31%) were classified as ward-ready. Eleven falls (42%) were witnessed and 12 (46%) occurred after hours, of which nine involved patients (75%) who had delirium. Seven falls (27%) occurred within 2 hours of a nursing shift change and 11 (42%) during a nursing break coverage. No patient sustained a major injury related to a fall but four (15%) reported minor injuries such as a laceration or abrasion. The median ICU stay after a fall was 2.2 days (IQR, 1.2-2.9 days). Compared with the matched non-fall cohort, patients who fell had a longer duration of ICU stay (median, 12.0 days [IQR, 8.3-18.6 days] v 4.7 days [IQR, 2.8-8.4 days]; P < 0.0001).

CONCLUSION

Falls in the ICU are infrequent and generally perceived as avoidable. Falls often occur at night, are unwitnessed and are associated with concomitant patient delirium and nursing shift changes and cross coverage.

Interobserver agreement for post mortem renal histopathology and diagnosis of acute tubular necrosis in critically ill patients

BACKGROUND

The renal histopathology of critically ill patients dying with acute kidney injury (AKI) in intensive care units of high income countries remains uncertain.

METHODS

Retrospective observational assessment of interobserver agreement in the reporting of renal post mortem histopathology, and the ability of pathologists blinded to the clinical context to independently identify the presence of pre-mortem AKI from digital images of histological sections from 34 critically ill patients dying in teaching hospitals in Australia and Canada.

RESULTS

We identified a heterogeneous cohort with a median age of 65 years (interquartile range [IQR], 56.5-77), APACHE II score of 27 (IQR, 19-33), and sepsis as the most common admission diagnosis (12/34; 35%). The most common proximate causes of death were cardiovascular (19/34; 56%) and respiratory (7/34; 21%) failure. AKI was common, with 23 patients (68%) developing RIFLE-F AKI, and 21 patients (62%) receiving renal replacement therapy. Structured reporting for tubular inflammation showed excellent agreement (kappa = 1), but no other subdomain demonstrated better than moderate agreement (kappa < 0.6). Only fair agreement (55.9% of cases; kappa = 0.23) was demonstrated on the diagnosis of moderate to severe acute tubular necrosis (ATN). Pathologist A predicted RIFLE-I or worse AKI with the diagnosis of ATN, with an overall accuracy of 61.8%; pathologist B predicted AKI with an accuracy of 35.3%.

CONCLUSIONS

Post mortem assessment of the renal histopathology in critically ill patients is neither robust nor reproducible; independent pathologists agree poorly on the diagnosis of ATN, and their structural assessment appears dissociated from ante-mortem renal function.

Restrictive or Liberal Red-Cell Transfusion for Cardiac Surgery

BACKGROUND

The effect of a restrictive versus liberal red-cell transfusion strategy on clinical outcomes in patients undergoing cardiac surgery remains unclear.

METHODS

In this multicenter, open-label, noninferiority trial, we randomly assigned 5243 adults undergoing cardiac surgery who had a European System for Cardiac Operative Risk Evaluation (EuroSCORE) I of 6 or more (on a scale from 0 to 47, with higher scores indicating a higher risk of death after cardiac surgery) to a restrictive red-cell transfusion threshold (transfuse if hemoglobin level was <7.5 g per deciliter, starting from induction of anesthesia) or a liberal red-cell transfusion threshold (transfuse if hemoglobin level was <9.5 g per deciliter in the operating room or intensive care unit [ICU] or was <8.5 g per deciliter in the non-ICU ward). The primary composite outcome was death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis by hospital discharge or by day 28, whichever came first. Secondary outcomes included red-cell transfusion and other clinical outcomes.

RESULTS

The primary outcome occurred in 11.4% of the patients in the restrictive-threshold group, as compared with 12.5% of those in the liberal-threshold group (absolute risk difference, -1.11 percentage points; 95% confidence interval [CI], -2.93 to 0.72; odds ratio, 0.90; 95% CI, 0.76 to 1.07; P<0.001 for noninferiority). Mortality was 3.0% in the restrictive-threshold group and 3.6% in the liberal-threshold group (odds ratio, 0.85; 95% CI, 0.62 to 1.16). Red-cell transfusion occurred in 52.3% of the patients in the restrictive-threshold group, as compared with 72.6% of those in the liberal-threshold group (odds ratio, 0.41; 95% CI, 0.37 to 0.47). There were no significant between-group differences with regard to the other secondary outcomes.

CONCLUSIONS

In patients undergoing cardiac surgery who were at moderate-to-high risk for death, a restrictive strategy regarding red-cell transfusion was noninferior to a liberal strategy with respect to the composite outcome of death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis, with less blood transfused. (Funded by the Canadian Institutes of Health Research and others; TRICS III ClinicalTrials.gov number, NCT02042898 .).

Association between e-alert implementation for detection of acute kidney injury and outcomes: a systematic review

Background

Electronic alerts (e-alerts) for acute kidney injury (AKI) in hospitalized patients are increasingly being implemented; however, their impact on outcomes remains uncertain.

Methods

We performed a systematic review. Electronic databases and grey literature were searched for original studies published between 1990 and 2016. Randomized, quasi-randomized, observational and before-and-after studies that included hospitalized patients, implemented e-alerts for AKI and described their impact on one of care processes, patient-centred outcomes or resource utilization measures were included.

Results

Our search yielded six studies ( n  = 10 165 patients). E-alerts were generally automated, triggered through electronic health records and not linked to clinical decision support. In pooled analysis, e-alerts did not improve mortality [odds ratio (OR) 1.05; 95% confidence intervals (CI), 0.84-1.31; n  = 3 studies; n  = 3425 patients; I 2  =   0%] or reduce renal replacement therapy (RRT) use (OR 1.20; 95% CI, 0.91-1.57; n  = 2 studies; n  = 3236 patients; I 2  =   0%). Isolated studies reported improvements in selected care processes. Pooled analysis found no significant differences in prescribed fluid therapy.

Conclusions

In the available studies, e-alerts for AKI do not improve survival or reduce RRT utilization. The impact of e-alerts on processes of care was variable. Additional research is needed to understand those aspects of e-alerts that are most likely to improve care processes and outcomes.

Permissive Underfeeding or Standard Enteral Feeding in High- and Low-Nutritional-Risk Critically Ill Adults. Post Hoc Analysis of the PermiT Trial

RATIONALE

The optimal nutritional strategy for critically ill adults at high nutritional risk is unclear.

OBJECTIVES

To examine the effect of permissive underfeeding with full protein intake compared with standard feeding on 90-day mortality in patients with different baseline nutritional risk.

METHODS

This is a post hoc analysis of the PermiT (Permissive Underfeeding versus Target Enteral Feeding in Adult Critically Ill Patients) trial.

MEASUREMENTS AND MAIN RESULTS

Nutritional risk was categorized by the modified Nutrition Risk in Critically Ill score, with high nutritional risk defined as a score of 5-9 and low nutritional risk as a score of 0-4. Additional analyses were performed by categorizing patients by body mass index, prealbumin, transferrin, phosphate, urinary urea nitrogen, and nitrogen balance. Based on the Nutrition Risk in Critically Ill score, 378 of 894 (42.3%) patients were categorized as high nutritional risk and 516 of 894 (57.7%) as low nutritional risk. There was no association between feeding strategy and mortality in the two categories; adjusted odds ratio (aOR) of 0.84 (95% confidence interval [CI], 0.56-1.27) for high nutritional risk and 1.01 (95% CI, 0.64-1.61) for low nutritional risk (interaction P = 0.53). Findings were similar in analyses using other definitions, with the exception of prealbumin. The association of permissive underfeeding versus standard feeding and 90-day mortality differed when patients were categorized by baseline prealbumin level (≤0.10 g/L: aOR, 0.57 [95% CI, 0.31-1.05]; >0.10 and ≤0.15 g/L: aOR, 0.79 [95% CI, 0.42-1.48]; >0.15 g/L: aOR, 1.55 [95% CI, 0.80, 3.01]; interaction P = 0.009).

CONCLUSIONS

Among patients with high and low nutritional risk, permissive underfeeding with full protein intake was associated with similar outcomes as standard feeding.

CRRTnet: a prospective, multi-national, observational study of continuous renal replacement therapy practices

Background

Continuous renal replacement therapy (CRRT) is the recommended modality of dialysis for critically ill patients with hemodynamic instability. Yet there remains significant variability in how CRRT is prescribed and delivered, and limited evidence-basis to guide practice.

Methods

This is a prospective, multi-center observational study of patients undergoing CRRT. Initial enrollment phase will occur at 4 academic medical centers in North America over 5 years, with a target enrollment of 2000 patients. All adult patients (18–89 years of age) receiving CRRT will be eligible for inclusion; patients who undergo CRRT for less than 24 h will be excluded from analysis. Data collection will include patient characteristics at baseline and at time of CRRT initiation; details of CRRT prescription and delivery, including machine-generated treatment data; and patient outcomes.

Discussion

The goal of this study is to establish a large comprehensive registry of critically ill adults receiving CRRT. Specific aims include describing variations in CRRT prescription and delivery across quality domains; validating quality measures for CRRT care by correlating processes and outcomes; and establishing a large registry for use in quality improvement and benchmarking efforts. For initial analyses, some particular areas of interest are anticoagulation protocols; approach to fluid overload; CRRT-related workload; and patient safety.

Trial registration

Registered on ClinicalTrials.gov 1/10/2014: NCT02034448.

Reconciling patient and provider priorities for improving the care of critically ill patients: A consensus method and qualitative analysis of decision making

Background

Providers have traditionally established priorities for quality improvement; however, patients and their family members have recently become involved in priority setting. Little is known about how to reconcile priorities of different stakeholder groups into a single prioritized list that is actionable for organizations.

Objective

To describe the decision‐making process for establishing consensus used by a diverse panel of stakeholders to reconcile two sets of quality improvement priorities (provider/decision maker priorities n=9; patient/family priorities n=19) into a single prioritized list.

Design

We employed a modified Delphi process with a diverse group of panellists to reconcile priorities for improving care of critically ill patients in the intensive care unit (ICU). Proceedings were audio‐recorded, transcribed and analysed using qualitative content analysis to explore the decision‐making process for establishing consensus.

Setting and participants

Nine panellists including three providers, three decision makers and three family members of previously critically ill patients.

Results

Panellists rated and revised 28 priorities over three rounds of review and reached consensus on the “Top 5” priorities for quality improvement: transition of patient care from ICU to hospital ward; family presence and effective communication; delirium screening and management; early mobilization; and transition of patient care between ICU providers. Four themes were identified as important for establishing consensus: storytelling (sharing personal experiences), amalgamating priorities (negotiating priority scope), considering evaluation criteria and having a priority champion.

Conclusions

Our study demonstrates the feasibility of incorporating families of patients into a multistakeholder prioritization exercise. The approach described can be used to guide consensus building and reconcile priorities of diverse stakeholder groups.

Pre-admission functional status impacts the performance of the APACHE IV model of mortality prediction in critically ill patients

BACKGROUND

Functional status (FS) before intensive care unit (ICU) admission is associated with short-term and long-term outcomes among critically ill patients. However, measures of FS are generally not integrated into ICU-specific mortality prediction models.

METHODS

This retrospective cohort study used prospectively collected data from 9638 consecutive patients admitted to a single ICU between 1 October 2005 and 30 September 2015. For each ICU admission, FS was prospectively determined and classified into three discrete categories based on performance of basic daily living activities (FS1 - fully independent; FS2 - partly dependent; FS3 - completely dependent). We prospectively calculated Acute Physiology and Chronic Health Evaluation (APACHE) IV predicted mortality percentage (APIV PM) for each admission and calculated observed-expected mortality ratios (OEMR), stratified by FS category and APIV PM. We calculated area under the receiver operator characteristic curve (AUC) for APIV PM and mortality for the entire cohort and the three FS categories.

RESULTS

Patients had a median (IQR) age of 67 (52-80) years and mean (SD) APIV PM was 18.3% (24.3%). Of these, 7714 (80.0%) were classified as FS1, 1728 (17.9%) as FS2 and 196 (2.0%) as FS3. FS1 patients were younger, had less comorbid disease, and lower APIV PM compared to FS2 and FS3. The OEMR were significantly lower for FS1 (0.67) than FS2 (0.93) or FS3 (0.90) (p < 0.0001 for both comparisons). Among patients with APIV PM 0-10%, 10-25%, 25-50% and ≥50% the OEMR for FS1 were 0.33, 0.49, 0.61 and 0.86. The AUC (95% CI) for APIV PM and mortality for FS1, FS2 and FS3 were 0.924 (0.914-0.933), 0.837 (0.816-0.858) and 0.775 (0.705-0.8456), respectively (p < 0.001 for each comparison). Multivariable analysis demonstrated that FS2 (OR 2.18 (1.84-2.57) (p < 0.0001)) and FS3 (OR 1.99 (1.34-2.96) (p = 0.0006)) were independently associated with increased risk of mortality.

CONCLUSIONS

Baseline FS prior to critical illness is a strong independent predictor of mortality and impacts the relationship between observed and APIV PM in those with lower illness severity. Future iterations of mortality prediction models should integrate a baseline measure of FS to improve performance.

A Scoping Review of Frailty and Acute Care in Middle-Aged and Older Individuals with Recommendations for Future Research

There is general agreement that frailty is a state of heightened vulnerability to stressors arising from impairments in multiple systems leading to declines in homeostatic reserve and resiliency, but unresolved issues persist about its detection, underlying pathophysiology, and relationship with aging, disability, and multimorbidity. A particularly challenging area is the relationship between frailty and hospitalization. Based on the deliberations of a 2014 Canadian expert consultation meeting and a scoping review of the relevant literature between 2005 and 2015, this discussion paper presents a review of the current state of knowledge on frailty in the acute care setting, including its prevalence and ability to both predict the occurrence and outcomes of hospitalization. The examination of the available evidence highlighted a number of specific clinical and research topics requiring additional study. We conclude with a series of consensus recommendations regarding future research priorities in this important area.

Acute kidney injury in sepsis

Acute kidney injury (AKI) and sepsis carry consensus definitions. The simultaneous presence of both identifies septic AKI. Septic AKI is the most common AKI syndrome in ICU and accounts for approximately half of all such AKI. Its pathophysiology remains poorly understood, but animal models and lack of histological changes suggest that, at least initially, septic AKI may be a functional phenomenon with combined microvascular shunting and tubular cell stress. The diagnosis remains based on clinical assessment and measurement of urinary output and serum creatinine. However, multiple biomarkers and especially cell cycle arrest biomarkers are gaining acceptance. Prevention of septic AKI remains based on the treatment of sepsis and on early resuscitation. Such resuscitation relies on the judicious use of both fluids and vasoactive drugs. In particular, there is strong evidence that starch-containing fluids are nephrotoxic and decrease renal function and suggestive evidence that chloride-rich fluid may also adversely affect renal function. Vasoactive drugs have variable effects on renal function in septic AKI. At this time, norepinephrine is the dominant agent, but vasopressin may also have a role. Despite supportive therapies, renal function may be temporarily or completely lost. In such patients, renal replacement therapy (RRT) becomes necessary. The optimal intensity of this therapy has been established, while the timing of when to commence RRT is now a focus of investigation. If sepsis resolves, the majority of patients recover renal function. Yet, even a single episode of septic AKI is associated with increased subsequent risk of chronic kidney disease.

Leveraging Big Data and Electronic Health Records to Enhance Novel Approaches to Acute Kidney Injury Research and Care

While acute kidney injury (AKI) has been poorly defined historically, a decade of effort has culminated in a standardized, consensus definition. In parallel, electronic health records (EHRs) have been adopted with greater regularity, clinical informatics approaches have been refined, and the field of EHR-enabled care improvement and research has burgeoned. Although both fields have matured in isolation, uniting the 2 has the capacity to redefine AKI-related care and research. This article describes how the application of a consistent AKI definition to the EHR dataset can accurately and rapidly diagnose and identify AKI events. Furthermore, this electronic, automated diagnostic strategy creates the opportunity to develop predictive approaches, optimize AKI alerts, and trace AKI events across institutions, care platforms, and administrative datasets.

Angiotensin II for the Treatment of High-Output Shock 3 (ATHOS-3): protocol for a phase III, double-blind, randomised controlled trial

OBJECTIVE

Catecholamine-resistant hypotension (CRH) is characterised by inadequate response to standard doses of vasopressors, and increased mortality. Our Angiotensin II for the Treatment of High-Output Shock 3 (ATHOS-3) trial compares the efficacy and safety of angiotensin II (ANGII) versus placebo in CRH.

DESIGN, SETTING AND PARTICIPANTS

A phase III, multicentre, randomised, placebo-controlled trial of LJPC-501 (synthetic ANGII) for CRH in up to 120 intensive care units. We have set a target of 300 critically ill patients with CRH receiving standard-of-care (SOC) vasopressor therapy (ie, catecholamine dose > 0.2 µg/kg/min for 6-48 hours to maintain a mean arterial pressure [MAP] of 55-70 mmHg). Calculation of a norepinephrine-equivalent vasopressor dose is critical to determining patient eligibility, as ANGII will supplement ongoing vasopressor therapy.

INTERVENTIONS

Stable patients will be randomised 1:1 to SOC vasopressor plus continuous intravenous infusion of ANGII or placebo for 48 hours, with an aim of achieving MAP of 75 mmHg for the first 3 hours. ANGII (initiated at 20 ng/ kg/min) will be titrated according to pre-specified guidelines until 48 hours, with patients followed until Day 7. Frequent vital sign and haemodynamic monitoring will support ANGII titration, safety monitoring and efficacy assessments.

MAIN OUTCOME MEASURES

The primary efficacy endpoint is MAP ≥ 75 mmHg or an increase of ≥ 10 mmHg at treatment Hour 3. Secondary endpoints include change in total and cardiovascular Sequential Organ Failure Assessment scores over 48 hours, and safety data.

CONCLUSION

Our study will investigate the utility of adding ANGII to current SOC vasopressor options to increase the efficacy and safety of CRH therapy.

Associations Between Fluid Balance and Outcomes in Critically Ill Children: A Protocol for a Systematic Review and Meta-analysis

Background:

Fluid therapy is a mainstay during the resuscitation of critically ill children. After initial stabilization, excessive fluid accumulation may lead to complications of fluid overload, which has been independently associated with increased risk for mortality and major morbidity in critically ill children.

Objectives:

Perform an evidence synthesis to describe the methods used to measure fluid balance, define fluid overload, and evaluate the association between fluid balance and outcomes in critically ill children.

Design:

Systematic review and meta-analysis.

Measurements:

Fluid balance, fluid accumulation, and fluid overload as defined by authors.

Methods:

We will search Ovid MEDLINE, Ovid EMBASE, Cochrane Library, and ProQuest, Dissertations and Theses. In addition, we will search www.clinicaltrials.gov, World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) and the proceedings of selected key conferences for ongoing and completed studies. Search strategy will be done in consultation with a research librarian. Clinical trials and observational studies (from database inception to present) in patients (<25 years) admitted to pediatric intensive care units (PICUs) reporting fluid balance, fluid accumulation, or fluid overload, and associated outcomes will be included. Language will not be restricted. Two reviewers will independently screen studies and extract data. Primary outcome is mortality, and secondary outcomes encompass critical care resource utilization. Quality of evidence and risk of bias will be assessed using the Newcastle-Ottawa Scale (NOS). Results will be synthesized qualitatively and pooled for meta-analysis if possible.

Limitations:

Quality of the included studies; lack of randomized trials; high degrees of expected heterogeneity; and variations in definitions of fluid balance and fluid overload between studies.

Conclusion:

We will comprehensively appraise and summarize the evidence of the association between fluid balance and outcomes in critically ill children, and in doing so attempt to harmonize definitions related to fluid balance, accumulation, and overload.

Systematic review registration:

PROSPERO: CRD42016036209.

Strategies for the optimal timing to start renal replacement therapy in critically ill patients with acute kidney injury

Renal replacement therapy (RRT) is increasingly utilized to support critically ill patients with severe acute kidney injury (AKI). The question of whether and when to start RRT for a critically ill patient with AKI has long troubled clinicians. When severe complications of AKI develop, the need to commence RRT is unambiguous. In the absence of such complications but in the presence of severe AKI, the optimal time and thresholds for starting RRT are uncertain. The majority of existing data have largely been derived from observational studies. These have been limited due to confounding by indication, considerable heterogeneity in case mix and illness severity, and variably applied definitions for both AKI and for how "timing" was anchored relative to starting RRT. It is unclear whether a preemptive or earlier strategy of RRT initiation aimed largely at avoiding complications related to AKI or a more conservative strategy where RRT is started in response to developing complications leads to better patient-centered outcomes and health services use. This question has been the focus of 2 recently completed randomized trials. In this review, we provide an appraisal of available evidence, discuss existing knowledge gaps, and provide perspective on future research that will better inform the optimal timing of RRT initiation in AKI.

The intensive care medicine agenda on acute kidney injury

Acute kidney injury (AKI) is a common complication in the critically ill. Current standard of care mainly relies on identification of patients at risk, haemodynamic optimization, avoidance of nephrotoxicity and the use of renal replacement therapy (RRT) in established AKI. The detection of early biomarkers of renal tissue damage is a recent development that allows amending the late and insensitive diagnosis with current AKI criteria. Increasing evidence suggests that the consequences of an episode of AKI extend long beyond the acute hospitalization. Citrate has been established as the anticoagulant of choice for continuous RRT. Conflicting results have been published on the optimal timing of RRT and on the renoprotective effect of remote ischaemic preconditioning. Recent research has contradicted that acute tubular necrosis is the common pathology in AKI, that septic AKI is due to global kidney hypoperfusion, that aggressive fluid therapy benefits the kidney, that vasopressor therapy harms the kidney and that high doses of RRT improve outcome. Remaining uncertainties include the impact of aetiology and clinical context on pathophysiology, therapy and prognosis, the clinical benefit of biomarker-driven interventions, the optimal mode of RRT to improve short- and long-term patient and kidney outcomes, the contribution of AKI to failure of other organs and the optimal approach for assessing and promoting renal recovery. Based on the established gaps in current knowledge the trials that must have priority in the coming 10 years are proposed together with the definition of appropriate clinical endpoints.

The Timing of Renal Replacement Therapy Initiation in Acute Kidney Injury

The optimal time to start renal replacement therapy (RRT) in the setting of acute kidney injury (AKI) is one of the most controversial questions in the field of critical care nephrology. An earlier or pre-emptive approach, whereby RRT is initiated in the absence of a life-threatening complication of AKI, may have a variety of plausible benefits. On the other hand, the widespread adoption of such an approach would consume more resources and would have to be justified by evidence of superior patient outcomes. It is possible that a more conservative strategy that reserves the initiation of RRT until an urgent indication is present might confer acceptable patient outcomes without exposing patients who are destined to recover from AKI spontaneously to the risks of unnecessary RRT. Ongoing randomized controlled trials should help bring clarity to this important area of clinical uncertainty.

Epidemiology of Acute Kidney Injury in Critically Ill Children and Young Adults

BACKGROUND

The epidemiologic characteristics of children and young adults with acute kidney injury have been described in single-center and retrospective studies. We conducted a multinational, prospective study involving patients admitted to pediatric intensive care units to define the incremental risk of death and complications associated with severe acute kidney injury.

METHODS

We used the Kidney Disease: Improving Global Outcomes criteria to define acute kidney injury. Severe acute kidney injury was defined as stage 2 or 3 acute kidney injury (plasma creatinine level ≥2 times the baseline level or urine output <0.5 ml per kilogram of body weight per hour for ≥12 hours) and was assessed for the first 7 days of intensive care. All patients 3 months to 25 years of age who were admitted to 1 of 32 participating units were screened during 3 consecutive months. The primary outcome was 28-day mortality.

RESULTS

A total of 4683 patients were evaluated; acute kidney injury developed in 1261 patients (26.9%; 95% confidence interval [CI], 25.6 to 28.2), and severe acute kidney injury developed in 543 patients (11.6%; 95% CI, 10.7 to 12.5). Severe acute kidney injury conferred an increased risk of death by day 28 after adjustment for 16 covariates (adjusted odds ratio, 1.77; 95% CI, 1.17 to 2.68); death occurred in 60 of the 543 patients (11.0%) with severe acute kidney injury versus 105 of the 4140 patients (2.5%) without severe acute kidney injury (P<0.001). Severe acute kidney injury was associated with increased use of mechanical ventilation and renal-replacement therapy. A stepwise increase in 28-day mortality was associated with worsening severity of acute kidney injury (P<0.001 by log-rank test). Assessment of acute kidney injury according to the plasma creatinine level alone failed to identify acute kidney injury in 67.2% of the patients with low urine output.

CONCLUSIONS

Acute kidney injury is common and is associated with poor outcomes, including increased mortality, among critically ill children and young adults. (Funded by the Pediatric Nephrology Center of Excellence at Cincinnati Children's Hospital Medical Center and others; AWARE ClinicalTrials.gov number, NCT01987921 .).

Outcomes of elderly critically ill medical and surgical patients: a multicentre cohort study

PURPOSE

Very elderly (over 80 yr of age) critically ill patients admitted to medical-surgical intensive care units (ICUs) have a high incidence of mortality, prolonged hospital length of stay, and dependent living conditions should they survive. The primary purpose of this study is to describe the outcomes and differences in outcomes between very elderly medical patients and their surgical counterparts admitted to Canadian ICUs, thereby informing decision-making for clinicians and substitute decision-makers.

METHODS

This was a prospective multicentre cohort study of very elderly medical and surgical patients admitted to 22 Canadian academic and non-academic ICUs. Outcome measures included ICU length of stay and mortality, hospital length of stay and mortality, and disposition following hospital discharge.

RESULTS

There were 1,671 patients evaluated in this study. Patient demographics included a mean age of 84.5 yr, baseline Acute Physiology and Chronic Health Evaluation (APACHE) II score of 22.4, baseline Sequential Organ Failure Assessment (SOFA) score of 5.3, overall ICU mortality of 21.8%, and overall hospital mortality of 35.0%. Medical patient median ICU length of stay was 4.1 days, hospital length of stay was 16.2 days, ICU mortality was 26.5%, and hospital mortality was 41.5%. Surgical patient median ICU length of stay was 3.8 days, hospital length of stay was 20.1 days, ICU mortality was 18.7%, and hospital mortality was 31.6%. Only 45.0% of medical patients and 41.6% of surgical emergency patients were able to return home to live.

CONCLUSIONS

In this large sample of critically ill medical and surgical patients, the admission SOFA score and hospital lengths of stay were not different between the two groups, but medical patients had longer ICU lengths of stay and higher ICU and hospital mortality than surgical patients.

Polymyxin B-immobilised haemoperfusion and mortality in critically ill patients with sepsis/septic shock: a protocol for a systematic review and meta-analysis

INTRODUCTION

Polymyxin-B immobilised haemoperfusion (PMX-HP) is a promising adjuvant strategy for the treatment of sepsis and septic shock. PMX-HP therapy works by clearing circulating endotoxin through binding to polymyxin-immobilised fibres during haemoperfusion. Small clinical trials have shown that PMX-HP therapy is associated with improved haemodynamic profile, oxygenation and survival. However, clear inferences have been largely inconclusive due to limitations in study design (eg, small, unblinded) and generalisability. We therefore propose to perform an up-to-date systematic review and evidence synthesis to describe the efficacy, safety and effectiveness of PMX-HP for adult patients with sepsis or septic shock.

METHODS AND ANALYSIS

We will search the following databases from 1946 to 2016 MEDLINE (Ovid), EMBASE (Ovid), Cochrane Library, Health Technology Assessment Database (HTA), Cumulative Index to Nursing and Allied Health Literature (CINAHL), PubMed and 'Igaku Chuo Zasshi' (ICHUSHI) for randomised controlled trials of PMX-HP in critically ill patients with sepsis or septic shock. There will be no language restrictions in the electronic search for studies. Two reviewers will extract data and appraise the quality of each study independently. The primary outcome will be the pooled risk ratio of 28-day all-cause mortality. Serious adverse events and changes in organ dysfunction scores will also be evaluated. The secondary outcomes will be 90-day all-cause mortality, changes in haemodynamic profile and endotoxin levels, and health services use.

ETHICS AND DISSEMINATION

Our systematic review will synthesise the evidence on use of the PMX-HP as an adjuvant therapy in sepsis/septic shock to improve patient-centred, physiological and health services outcomes. Research ethics is not required for this review. The study will be disseminated by peer-reviewed publication and conference presentation.

TRIAL REGISTRATION NUMBER

CRD42016038356.