Corticosteroid therapy in critical illness due to seasonal and pandemic influenza

BACKGROUND:

Survey data suggest that Canadian intensivists administer corticosteroids to critically ill patients primarily in response to airway obstruction, perceived risk for adrenal insufficiency and hemodynamic instability.

OBJECTIVE:

To describe variables independently associated with systemic corticosteroid therapy during an influenza outbreak.

METHODS:

The present analysis was retrospective cohort study involving critically ill patients with influenza in two Canadian cities. Hospital records were reviewed for critically ill patients treated in the intensive care units (ICUs) of eight hospitals in Canada during the 2008 to 2009 and 2009 to 2010 influenza outbreaks. Abstracted data included demographic information, symptoms at disease onset, chronic comorbidities and baseline illness severity scores. Corticosteroid use data were extracted for every ICU day and expressed as hydrocortisone dose equivalent in mg. Multivariable regression models were constructed to identify variables independently associated with corticosteroid therapy in the ICU.

RESULTS:

The study cohort included 90 patients with a mean (± SD) age of 55.0±17.3 years and Acute Physiology and Chronic Health Evaluation II score of 19.8±8.3. Patients in 2009 to 2010 were younger with more severe lung injury but similar exposure to corticosteroids. Overall, 54% of patients received corticosteroids at a mean daily dose of 343±330 mg of hydrocortisone for 8.5±4.8 days. Variables independently associated with corticosteroid therapy in the ICU were history of airway obstruction (OR 4.8 [95% CI 1.6 to 14.9]) and hemodynamic instability (OR 4.6 [95% CI 1.2 to 17.8]).

CONCLUSION:

Observational data revealed that hemodynamic instability and airway obstruction were associated with corticosteroid therapy in the critical care setting, similar to a recent survey of stated practice. Efforts to determine the effects of corticosteroids in the ICU for these specific clinical situations are warranted.     

Retrospective Outcomes of Glucose Control in Critically Ill Children

Background

Hyperglycemia is a significant problem for critically ill children. Treatment for hyperglycemia remains controversial. This study explores the effect of controlling blood glucose (BG) in hyperglycemic critically ill children.

Methods

A retrospective cohort of nondiabetic critically ill children (defined as requiring mechanical ventilation and/or vasopressors) with BG persistently ≥150 mg/dl and treated with insulin (treatment group) were compared with a historical cohort of similar children who did not receive interventions to control hyperglycemia (baseline group).

Results

There were 130 children in the treatment group and 137 children in the baseline group. Mean BG in the treatment group was 140 ± 24 mg/dl compared with 179 ± 47 mg/dl in the baseline group (p < .001). After adjusting for patient characteristics, cointerventions, and glucose metrics, patients in the treatment group had 2.5 fewer intensive care unit (ICU)-free days (i.e., number of days alive and discharged from ICU within 28 days after inclusion) than the baseline group (p = .023). Glucose control was not independently associated with duration of ICU stay, ventilator-free days, vasopressor-free days, or mortality.

Conclusions

Blood glucose control appears associated with worse outcomes in critically ill children. Our data combined with conflicting results in adults leads us to strongly advocate for the conduct of randomized trials on glucose control in critically ill children.     

Associations between Intensity of RRT,Inflammatory Mediators,and Outcomes

Background and objectives

Critically ill patients requiring RRT have higher circulating plasma concentrations of inflammatory and apoptosis markers that are associated with subsequent RRT dependence and death. Whether intensive dosing of RRT is associated with changes in specific mediators is unknown.

Design, setting, participants, & measurements

A multicenter, prospective, cohort study of 817 critically ill patients receiving RRT ancillary to the Veterans Affairs/National Institutes of Health Acute Renal Failure Trial Network study was conducted between November 2003 and July 2007. Plasma inflammatory (IL-6, IL-8, IL-10, IL-18, and macrophage migration inhibitory factor) and apoptosis (TNF receptor-I [TNFR-I], TNFR-II, and death receptor-5) biomarkers on days 1 and 8 were examined after initiation of intensive RRT. Whether intensive RRT, given day 1 biomarkers, is associated with RRT independence and lower mortality at day 60 was also examined.

Results

Overall, no differences were found in day 8 biomarker concentrations between intensive and less-intensive RRT groups. When adjusted for day 1 biomarkers and clinical variables, intensive RRT was not associated with renal recovery (adjusted odds ratio [OR], 0.80; 95% confidence interval, 0.56 to 1.14) or mortality (adjusted OR, 1.15; 95% confidence interval, 0.81 to 1.64). Use of intensive RRT, however, was associated with lower day 8 concentrations when day 1 plasma IL-6, macrophage migration inhibitory factor, and TNFR-I concentrations were high (interaction P value for all markers, <0.01). In contrast, day 8 marker concentrations were higher when day 1 levels were low (P<0.01). Elevated biomarker concentrations on day 8 among 476 participants were associated with lower renal recovery (adjusted OR range, 0.19–0.87) and higher mortality (adjusted OR range, 1.26–3.18).

Conclusions

Among critically ill patients receiving RRT, intensive dosing of RRT has variable association with biomarker concentration and no association with renal recovery and mortality. However, elevated concentrations of inflammatory and apoptosis markers on day 8 of RRT were associated with RRT dependence and death.     

Assessment of blood glucose control in the pediatric intensive care unit: extension of the glycemic penalty index toward children and infants

Background:

The glycemic penalty index (GPI) is a measure to assess blood glucose (BG) control in critically ill adult patients but needs to be adapted for children and infants.

Method:

The squared differences between a clinical expertise penalty function and the corresponding polynomial function are minimized for optimization purposes. The average of all penalties (individually assigned to all BG readings) represents the patient-specific GPI.

Results:

Penalization in the hypoglycemic range is more severe than in the hyperglycemic range as the developing brains of infants and children may be more vulnerable to hypoglycemia. Similarly, hypoglycemia is also more heavily penalized in infants than in children.

Conclusions:

Extending the adult GPI toward the age-specific GPI is an important methodological step. Long-term clinical studies are needed to determine the clinically acceptable GPI cut-off level.     

Analytic Evaluation of a New Glucose Meter System in 15 Different Critical Care Settings

Background

Maintaining appropriate glycemic control in critically ill patients reduces morbidity and mortality. The use of point-of-care (POC) glucose devices is necessary to obtain rapid results at the patient’s bedside. However, the devices should be thoroughly tested in the intended population before implementation. The use of POC glucose meters in critically ill patients has been questioned both in the literature and by regulatory agencies. The aim of this study was to determine if the ACCU-CHEK^® Inform II system (Roche Diagnostics) POC glucose meter demonstrated the desired accuracy and precision, as defined by Clinical and Laboratory Standards Institute guideline POCT12-A3, in a large number of critically ill patients from multiple intensive care settings at two academic medical centers.

Methods

A total of 1200 whole blood meter results from 600 patients were compared with central laboratory plasma values. Whole blood aliquots from venous samples were used to obtain duplicate meter results with the remaining sample being processed to obtain plasma for central laboratory testing within 5 min of meter testing.

Results

A total of 1185 (98.8%) of the new meter’s glucose values were within ±12.5% (±12 mg/dl for values ≥100 mg/dl) of the comparative laboratory glucose values, and 1198 (99.8%) were within ±20% (±20 mg/dl for values <100 mg/dl).

Conclusions

Considering the large number of patients from numerous critical care units examined, the new glucose meter system appears to have sufficient analytic accuracy for use in critically ill patients.     

Incorporation of Biomarkers with the Renal Angina Index for Prediction of Severe AKI in Critically Ill Children

Background and objectives

Novel AKI biomarkers carry variable performance for prediction of AKI in patients with heterogeneous illness. Until utility is demonstrated in critically ill patients outside of the cardiopulmonary bypass population, AKI biomarkers are unlikely to gain widespread implementation. Operationalization of an AKI risk stratification methodology, termed renal angina, was recently reported to enhance prediction at the time of intensive care unit admission for persistent severe AKI. The renal angina index (RAI) was developed to provide the clinical context to direct AKI biomarker testing. This study tested the hypothesis that incorporation of AKI biomarkers in patients fulfilling renal angina improves the prediction of persistent severe AKI.

Design, setting, participants, & measurements

In a multicenter study of 214 patients admitted to the pediatric intensive care unit with sepsis, the discrimination of plasma neutrophil gelatinase–associated lipocalin (NGAL), matrix metalloproteinase-8 (MMP-8), and neutrophil elastase-2 (Ela-2) were determined individually and in combination with the RAI for severe AKI. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were calculated.

Results

Individual biomarkers demonstrated marginal discrimination for severe AKI (area under curve [AUC]: NGAL, 0.72; MMP-8, 0.68; Ela-2, 0.72), inferior to prediction by the clinical model of the RAI (AUC=0.80). Incorporation of each biomarker significantly added to the renal angina model AKI prediction (AUC=0.80, increased to 0.84–0.88; P<0.05 for each). The inclusion of each biomarker with the RAI demonstrated NRI (0.512, 0.428, and 0.545 for NGAL, MMP-8, and Ela-2, respectively; all P<0.03) and IDI (0.075 for Ela-2). The inclusion of both Ela-2 and NGAL with RAI demonstrated an NRI of 0.871 (P<0.001) and an IDI of 0.1 (P=0.01).

Conclusions

This study shows that incorporation of AKI biomarkers into the RAI improves discrimination for severe AKI. The RAI optimizes the utility of AKI biomarkers in a heterogeneous, critically ill patient population.     

Parenteral nutrition-associated hyperglycemia in noncritically ill inpatients is associated with higher mortality

BACKGROUND:

Hyperglycemia is a marker of poor clinical outcomes in studies evaluating hospitalized critically ill patients.

OBJECTIVES:

To identify whether glycemic control is associated with health outcomes including acute coronary events, renal failure, infection, hospital length of stay, intensive care unit (ICU) admission, sepsis and mortality in noncritically ill patients administered parenteral nutrition (PN), and to compare the current standard of care for glucose monitoring at the Foothills Medical Centre (Calgary, Alberta) with the 2009 American Society of Parenteral and Enteral Nutrition guidelines.

METHODS:

A retrospective chart review of 100 adult (18 years of age or older) non-ICU inpatients who received PN for seven days or longer at the Foothills Medical Centre was conducted.

RESULTS:

Seventeen patients (17%) had a mean blood glucose level of 10.0 mmol/L or greater. PN patients with a mean blood glucose level of 10 mmol/L or greater had a higher rate of mortality than patients with a mean blood glucose level of less than 10 mmol/L (OR 7.22; 95% CI 1.08 to 48.29; P=0.042). Hyperglycemia was independently and significantly associated with mortality when adjusted for age and sex. Acute coronary events, renal failure, infection, hospital length of stay, ventilator use and ICU admissions were not associated with hyperglycemia. Only one-half of those with hyperglycemia, and none of the patients in the euglycemic group, received adequate glucose monitoring during the first two days of PN.

CONCLUSION:

Hyperglycemia in noncritically ill inpatients receiving PN was found to be a risk factor for increased mortality.     

Use of a novel fluorescent glucose sensor in volunteer subjects with type 1 diabetes mellitus

Background:

Stress hyperglycemia in the critically ill has been found to be associated with increased morbidity and mortality. Studies have found significant improvements in morbidity and mortality in postsurgical patients whose glucose levels were closely maintained in the euglycemic range. However, subsequent studies, in particular the Normoglycemia in Intensive Care Evaluation and Survival Using Glucose Algorithm Regulation (NICE-SUGAR) study, found no improvement in subjects with tight glycemic control. In addition to differences in protocol design, patients in the tight glycemic control arm of the NICE-SUGAR study experienced high rates of hypoglycemia compared with other studies. One interpretation of the NICE-SUGAR study results is that it is difficult to achieve normal glycemia in critically ill patients with existing glucose monitoring technology. The purpose of the study reported here was to evaluate the safety and performance of a continuous intravascular glucose sensor that could be used in the future in critically ill patients.

Methods:

A first-generation prototype of an intravascular continuous glucose sensor was evaluated in 29 volunteer subjects with type 1 diabetes mellitus. The sensor operates on the principle of quenched fluorescence. The fluorescent emission from the sensor chemistry is nonlinear, resulting in improved accuracy in the hypoglycemic range. The duration of each study was 8 hours. Sensor output was compared with temporally correlated reference measurements made from venous samples on a laboratory glucose analyzer.

Results:

Data were obtained from 18 of the 29 subjects in the study. Data were analyzed retrospectively using a factory calibration plus a one-point in vivo calibration. The mean absolute relative difference was 7.97%, and 95.1% of all the points were in zone A of the Clarke error grid.

Conclusions:

This pilot study was the first use in human subjects of a prototype of the GluCath Intravascular Continuous Glucose Monitoring System (GluCath System). The GluCath System is based on a novel fluorescent sensor chemistry. The study found the GluCath System had a high level of accuracy as compared with a laboratory reference analyzer.     

Epstein-Barr Virus Infection Mimicking Drug-Induced Hepatitis in a Critically ill Patient During Antituberculosis Therapy

Introduction:

Although hepatitis is frequently observed during antituberculosis (anti-TB) therapy, acute viral hepatitis should be ruled out first, especially in the endemic areas. In addition to common types of viral hepatitis, ie, hepatitis A, hepatitis B, and hepatitis C viruses, Epstein-Barr virus (EBV) may result in hepatitis in some cases.

Case Presentation:

Herein, we reported a critically ill patient who developed cholestatic hepatitis in the intensive care unit during the anti-TB therapy, which was misdiagnosed as anti-TB agents-induced hepatitis in the beginning. Further serologic tests and liver biopsy confirmed the diagnosis of EBV hepatitis. In contrast to previously reported hepatitis by EBV, which had presented with transient liver dysfunction and self-limiting illness, hepatitis with progressive jaundice was followed by coagulopathy and encephalopathy in our case and the patient died of hepatic failure complications.

Conclusions:

According to the presented case and subsequent literature review on fatal EBV hepatitis, clinicians should consider EBV infection in the differential diagnosis when hepatitis occurs in critically ill patients during the anti-TB therapy. Although hepatitis caused by EBV is mostly self-limited, some might be fetal.     

Duration of antibiotic therapy for critically ill patients with bloodstream infections: A retrospective cohort study

BACKGROUND:

The optimal duration of antibiotic treatment for bloodstream infections is unknown and understudied.

METHODS:

A retrospective cohort study of critically ill patients with bloodstream infections diagnosed in a tertiary care hospital between March 1, 2010 and March 31, 2011 was undertaken. The impact of patient, pathogen and infectious syndrome characteristics on selection of shorter (≤10 days) or longer (>10 days) treatment duration, and on the number of antibiotic-free days, was examined. The time profile of clinical response was evaluated over the first 14 days of treatment. Relapse, secondary infection and mortality rates were compared between those receiving shorter or longer treatment.

RESULTS:

Among 100 critically ill patients with bloodstream infection, the median duration of antibiotic treatment was 11 days, but was highly variable (interquartile range 4.5 to 17 days). Predictors of longer treatment (fewer antibiotic-free days) included foci with established requirements for prolonged treatment, underlying respiratory tract focus, and infection with Staphylococcus aureus or Pseudomonas species. Predictors of shorter treatment (more antibiotic-free days) included vascular catheter source and bacteremia with coagulase-negative staphylococci. Temperature improvements plateaued after the first week; white blood cell counts, multiple organ dysfunction scores and vasopressor dependence continued to decline into the second week. Among 72 patients who survived to 10 days, clinical outcomes were similar between those receiving shorter and longer treatment.

CONCLUSION:

Antibiotic treatment durations for patients with bloodstream infection are highly variable and often prolonged. A randomized trial is needed to determine the duration of treatment that will maximize cure while minimizing adverse consequences of antibiotics.     

Mobility therapy and central or peripheral catheter-related adverse events in an ICU in Brazil

OBJECTIVE:

To determine whether mobility therapy is associated with central or peripheral catheter-related adverse events in critically ill patients in an ICU in Brazil.

METHODS:

A retrospective analysis of the daily medical records of patients admitted to the Clinical Emergency ICU of the University of São Paulo School of Medicine Hospital das Clínicas Central Institute between December of 2009 and April of 2011. In addition to the demographic and clinical characteristics of the patients, we collected data related to central venous catheters (CVCs), hemodialysis (HD) catheters and indwelling arterial catheters (IACs): insertion site; number of catheter days; and types of adverse events. We also characterized the mobility therapy provided.

RESULTS:

Among the 275 patients evaluated, CVCs were used in 49%, HD catheters were used in 26%, and IACs were used in 29%. A total of 1,268 mobility therapy sessions were provided to patients while they had a catheter in place. Catheter-related adverse events occurred in 20 patients (a total of 22 adverse events): 32%, infection; 32%, obstruction; and 32%, accidental dislodgement. We found that mobility therapy was not significantly associated with any catheter-related adverse event, regardless of the type of catheter employed: CVC-OR = 0.8; 95% CI: 0.7-1.0; p = 0.14; HD catheter-OR = 1.04; 95% CI: 0.89-1.21; p = 0.56; or IAC-OR = 1.74; 95% CI: 0.94-3.23; p = 0.07.

CONCLUSIONS:

In critically ill patients, mobility therapy is not associated with the incidence of adverse events involving CVCs, HD catheters, or IACs.     

Red cell distribution width is associated with hospital mortality in unselected critically ill patients

Background and objectives

Red cell distribution width (RDW) is a variability of red cell sizes and has been associated with outcomes in many clinical settings. Its prognostic value in intensive care unit (ICU) has been reported but requires confirmation. The study aimed to investigate the role of RDW in predicting hospital mortality in critically ill patients.

Methods

This is a retrospective study conducted in a 24-bed ICU of a tertiary teaching hospital. Data on demographic characteristics and laboratory measurements were collected from medical information database. Baseline variables were compared between survivors and nonsurvivors. The primary endpoint was hospital mortality; and ICU length of stays (LOS) were compared between patients with RDW >14.8% and ≤14.8%. The predictive value of RDW was also measured using receiver operating characteristic (ROC) curves. Two-sided P<0.05 was considered to be statistically significant.

Results

A total of 1,539 patients were enrolled during study period, including 1,084 survivors and 455 nonsurvivors. In univariate analysis, variables such as age, sex, primary diagnosis, C-reactive protein (CRP), RDW and albumin were significantly associated with hospital mortality. RDW remained significantly associated with mortality after adjustment for sex, age, Charlson index albumin and CRP, with an odds ratio of 1.1 (95% CI: 1.03-1.16). Diagnostic performance of RDW in predicting mortality appeared to be suboptimal (AU-ROC: 0.62). Changes in RDW during a short follow up period were not associated with mortality.

Conclusions

RDW measured on ICU entry is associated with hospital mortality. Patients with higher RDW will have longer LOS in ICU. Repeated measurements of RDW provide no additional prognostic value in critically ill patients.KEYWORDS : Red cell distribution width (RDW), intensive care unit (ICU), mortality, length of stay (LOS)     

Macrolide use in the treatment of critically ill patients with pneumonia: Incidence,correlates, timing and outcomes

BACKGROUND:

Macrolide antibiotics are commonly used to treat pneumonia despite increasing antimicrobial resistance. Evidence suggests that macrolides may also decrease mortality in severe sepsis via immunomodulatory properties.

OBJECTIVE:

To evaluate the incidence, correlates, timing and mortality associated with macrolide-based treatment.

METHODS:

A population-based cohort of critically ill adults with pneumonia at five intensive care units in Edmonton, Alberta, was prospectively followed over two years. Data collected included disease severity (Acute Physiology and Chronic Health Evaluation [APACHE] II score), pneumonia severity (Pneumonia Severity Index score), comorbidities, antibiotic treatments at presentation and time to effective antibiotic. The independent association between macrolide-based treatment and 30-day all-cause mortality was examined using multivariable Cox regression. A secondary exploratory analysis examined time to effective antimicrobial therapy.

RESULTS:

The cohort included 328 patients with a mean Pneumonia Severity Index score of 116 and a mean APACHE II score of 17; 84% required invasive mechanical ventilation. Ninety-one (28%) patients received macrolide-based treatments, with no significant correlates of treatment except nursing home residence (15% versus 30% for nonresidents [P=0.02]). Overall mortality was 54 of 328 (16%) at 30 days: 14 of 91 (15%) among patients treated with macrolides versus 40 of 237 (17%) for nonmacrolides (adjusted HR 0.93 [95% CI 0.50 to 1.74]; P=0.8). Patients who received effective antibiotics within 4 h of presentation were less likely to die than those whose treatment was delayed (14% versus 17%; adjusted HR 0.50 [95% CI 0.27 to 0.94]; P=0.03).

CONCLUSIONS:

Macrolide-based treatment was not associated with lower 30-day mortality among critically ill patients with pneumonia, although receipt of effective antibiotic within 4 h was strongly predictive of survival. Based on these results, timely effective treatment may be more important than choice of antibiotics.     

Model to predict mortality in critically ill adults with acute kidney injury

Summary

Background and objectives

Acute kidney injury (AKI) requiring dialysis is associated with high mortality. Most prognostic tools used to describe case complexity and to project patient outcome lack predictive accuracy when applied in patients with AKI. In this study, we developed an AKI-specific predictive model for 60-day mortality and compared the model to the performance of two generic (Sequential Organ Failure Assessment [SOFA] and Acute Physiology and Chronic Health Evaluation II [APACHE II]) scores, and a disease specific (Cleveland Clinic [CCF]) score.

Design, setting, participants, & measurements

Data from 1122 subjects enrolled in the Veterans Affairs/National Institutes of Health Acute Renal Failure Trial Network study; a multicenter randomized trial of intensive versus less intensive renal support in critically ill patients with AKI conducted between November 2003 and July 2007 at 27 VA- and university-affiliated centers.

Results

The 60-day mortality was 53%. Twenty-one independent predictors of 60-day mortality were identified. The logistic regression model exhibited good discrimination, with an area under the receiver operating characteristic (ROC) curve of 0.85 (0.83 to 0.88), and a derived integer risk score yielded a value of 0.80 (0.77 to 0.83). Existing scoring systems, including APACHE II, SOFA, and CCF, when applied to our cohort, showed relatively poor discrimination, reflected by areas under the ROC curve of 0.68 (0.64 to 0.71), 0.69 (0.66 to 0.73), and 0.65 (0.62 to 0.69), respectively.

Conclusions

Our new risk model outperformed existing generic and disease-specific scoring systems in predicting 60-day mortality in critically ill patients with AKI. The current model requires external validation before it can be applied to other patient populations.     

Effluent Volume in Continuous Renal Replacement Therapy Overestimates the Delivered Dose of Dialysis

Summary

Background and objectives

Studies examining dose of continuous renal replacement therapy (CRRT) and outcomes have yielded conflicting results. Most studies considered the prescribed dose as the effluent rate represented by ml/kg per hour and reported this volume as a surrogate of solute removal. Because filter fouling can reduce the efficacy of solute clearance, the actual delivered dose may be substantially lower than the observed effluent rate.

Design, setting, participants, & measurements

Data were examined from 52 critically ill patients with acute kidney injury (AKI) requiring dialysis. All patients were treated with predilution continuous venovenous hemodiafiltration (CVVHDF) and regional citrate anticoagulation. Filter performance was monitored during the entire course of therapy by measuring blood urea nitrogen (BUN) and dialysis fluid urea nitrogen (FUN) at initiation and every 12 hours. Filter efficacy was assessed by calculating FUN/BUN ratios every 12 hours of filter use. Prescribed urea clearance (K, ml/min) was determined from the effluent rate. Actual delivered urea clearance was determined using dialysis-side measurements.

Results

Median daily treatment time was 1413 minutes (1260 to 1440) with a total effluent volume of 46.4 ± 17.4 L and urea mass removal of 13.0 ± 7.6 mg/min. Prescribed clearance overestimated the actual delivered clearance by 23.8%. This gap between prescribed and delivered clearance was related to the decrease in filter function assessed by the FUN/BUN ratio.

Conclusions

Effluent volume significantly overestimates delivered dose of small solutes in CRRT. To assess adequacy of CRRT, solute clearance should be measured rather than estimated by the effluent volume.     

Mechanical circulatory support with the ABIOMED BVS 5000: the Toronto General Hospital experience

BACKGROUND

Acute hemodynamic collapse resulting in cardiogenic shock and impending end-organ failure is usually associated with certain death. The introduction of short-term mechanical circulatory support (MCS) devices offers potential therapy to these critically ill patients. The BVS 5000 device (ABIOMED Inc, USA) is widely used in the United States, but rarely in Canada, where device reimbursement remains a barrier.

OBJECTIVE

To present the Toronto General Hospital’s (Toronto, Ontario) initial five-year experience with this device to highlight the indications for use, common complications and overall success rates.

METHODS AND RESULTS

The institutional MCS database from 2001 to 2006 was reviewed, and 18 patients who received 30 devices in a variety of configurations were identified. The most common support configuration consisted of biventricular support (n=12), followed by isolated left ventricular support (n=4) and isolated right ventricular support in two recipients of an implantable long-term left ventricular assist device. Overall survival to device explant or transplant was 55% (n=10), of which five (50%) were successfully discharged from the hospital. The overall survival from device implant to hospital discharge was 28% (five of 18). The most common cause of death was multisystem organ failure.

CONCLUSIONS

MCS with the ABIOMED BVS 5000 can successfully resuscitate critically ill patients; however, earlier institution of this device would avoid irreversible end-organ injury, and lead to higher rates of device explant and hospital discharge. Short-term MCS devices should be available in all cardiac surgical centres in Canada to permit stabilization and evaluation of the acutely ill cardiac patient and subsequent management in a heart transplant facility.     

The effect of rapid response teams on end-of-life care: A retrospective chart review

BACKGROUND:

A subset of critically ill patients have end-of-life (EOL) goals that are unclear. Rapid response teams (RRTs) may aid in the identification of these patients and the delivery of their EOL care.

OBJECTIVES:

To characterize the impact of RRT discussion on EOL care, and to examine how a preprinted order (PPO) set for EOL care influenced EOL discussions and outcomes.

METHODS:

A single-centre retrospective chart review of all RRT calls (January 2009 to December 2010) was performed. The effect of RRT EOL discussions and the effect of a hospital-wide PPO set on EOL care was examined. Charts were from the Ontario Ministry of Health and Long-Term Care Critical Care Information Systemic database, and were interrogated by two reviewers.

RESULTS:

In patients whose EOL status changed following RRT EOL discussion, there were fewer intensive care unit (ICU) transfers (8.4% versus 17%; P<0.001), decreased ICU length of stay (5.8 days versus 20 days; P=0.08), increased palliative care consultations (34% versus 5.3%; P<0.001) and an increased proportion who died within 24 h of consultation (25% versus 8.3%; P<0.001). More patients experienced a change in EOL status following the introduction of an EOL PPO, from 20% (before) to 31% (after) (P<0.05).

CONCLUSIONS:

A change in EOL status following RRT-led EOL discussion was associated with reduced ICU transfers and enhanced access to palliative care services. Further study is required to identify and deconstruct barriers impairing timely and appropriate EOL discussions.     

HMG–CoA Reductase Activation and Urinary Pellet Cholesterol Elevations in Acute Kidney Injury

Summary

Background and objectives

Experimental acute kidney injury (AKI) activates the HMG–CoA reductase (HMGCR) gene, producing proximal tubule cholesterol loading. AKI also causes sloughing of proximal tubular cell debris into tubular lumina. This study tested whether these two processes culminate in increased urinary pellet cholesterol content, and whether the latter has potential AKI biomarker utility.

Design, setting, participants, & measurements

Urine samples were collected from 29 critically ill patients with (n = 14) or without (n= 15) AKI, 15 patients with chronic kidney disease, and 15 healthy volunteers. Centrifuged urinary pellets underwent lipid extraction, and the extracts were assayed for cholesterol content (factored by membrane phospholipid phosphate content). In vivo HMGCR activation was sought by measuring levels of RNA polymerase II (Pol II), and of a gene activating histone mark (H3K4m3) at exon 1 of the HMGCR gene (chromatin immunoprecipitation assay of urine chromatin samples).

Results

AKI+ patients had an approximate doubling of urinary pellet cholesterol content compared with control urine samples (versus normal; P < 0.001). The values significantly correlated (r, 0.5; P < 0.01) with serum, but not urine, creatinine concentrations. Conversely, neither critical illness without AKI nor chronic kidney disease raised pellet cholesterol levels. Increased HMGCR activity in the AKI+ patients was supported by three- to fourfold increased levels of Pol II, and of H3K4m3, at the HMGCR gene (versus controls or AKI− patients).

Conclusions

(1) Clinical AKI, like experimental AKI, induces HMGCR gene activation; (2) increased urinary pellet cholesterol levels result; and (3) urine pellet cholesterol levels may have potential AKI biomarker utility. The latter will require future testing in a large prospective trial.     

Clinical implications of DNA methylation in hepatocellular carcinoma

Background

Epigenetics is a rapidly evolving field of genetic study applicable to nearly every aspect of genome-related research. The importance of epigenetics has been recognised in human hepatocellular carcinoma (HCC). Changes in DNA methylation patterns, including global hypomethylation and promoter hypermethylation, are thought to be early events in hepatocarcinogenesis.

Objectives

This review aimed to summarise the role of epigenetics in HCC, to describe the mechanisms of epigenetic changes in HCC and to examine the clinical relevance of epigenetics in HCC.

Methods

This review examines the role of CpG-rich regions and DNA methylation, and describes an epigenetic model of cancer, tumour type-specific methylation, the relationships among methylation, cirrhosis and hepatocarcinogenesis, and the role of DNA methylation in HCC. The clinical implications of epigenetics in HCC are discussed.

Results

A multivariate predictor model based on traditional clinical factors and DNA methylation profile may have important applications in the early detection of neoplastic transformation in populations at high risk for HCC. CpG methylation may be valuable in HCC prognostics. DNA methylation profiles may enable clinical prediction in pre-therapy patient biopsies, paraffin-embedded samples or plasma DNA.

Conclusions

Epigenetic changes and profiles may correlate to the biological behaviour of tumours and clinical outcome of HCC patients. The use of DNA methylation profiles as a surrogate biomarker remains an active area of clinical cancer research.