Adjudication of a primary trial outcome: Results of a calibration exercise and protocol for a large international trial

Background

Ascertainment of the severity of the primary outcome of upper gastrointestinal (GI) bleeding is integral to stress ulcer prophylaxis trials. This protocol outlines the adjudication process for GI bleeding events in an international trial comparing pantoprazole to placebo in critically ill patients (REVISE: Re-Evaluating the Inhibition of Stress Erosions). The primary objective of the adjudication process is to assess episodes submitted by participating sites to determine which fulfil the definition of the primary efficacy outcome of clinically important upper GI bleeding. Secondary objectives are to categorize the bleeding severity if deemed not clinically important, and adjudicate the bleeding site, timing, investigations, and treatments.

Methods

Research coordinators follow patients daily for any suspected clinically important upper GI bleeding, and submit case report forms, doctors' and nurses' notes, laboratory, imaging, and procedural reports to the methods center. An international central adjudication committee reflecting diverse specialty backgrounds conducted an initial calibration exercise to delineate the scope of the adjudication process, review components of the definition, and agree on how each criterion will be considered fulfilled. Henceforth, bleeding events will be stratified by study drug, and randomly assigned to adjudicator pairs (blinded to treatment allocation, and study center).

Results

Crude agreement, chance-corrected agreement, or chance-independent agreement if data have a skewed distribution will be calculated.

Conclusions

Focusing on consistency and accuracy, central independent blinded duplicate adjudication of suspected clinically important upper GI bleeding events will determine which events fulfil the definition of the primary efficacy outcome for this stress ulcer prophylaxis trial.

Registration

NCT03374800 (REVISE: Re-Evaluating the Inhibition of Stress Erosions).

Intensive care unit interventions to promote sleep and circadian biology in reducing incident delirium: a scoping review

RATIONALE/OBJECTIVES

Despite plausible pathophysiological mechanisms, research is needed to confirm the relationship between sleep, circadian rhythm and delirium in patients admitted to the intensive care unit (ICU). The objective of this review is to summarise existing studies promoting, in whole or in part, the normalisation of sleep and circadian biology and their impact on the incidence, prevalence, duration and/or severity of delirium in ICU.

METHODS

A sensitive search of electronic databases and conference proceedings was completed in March 2023. Inclusion criteria were English-language studies of any design that evaluated in-ICU non-pharmacological, pharmacological or mixed intervention strategies for promoting sleep or circadian biology and their association with delirium, as assessed at least daily. Data were extracted and independently verified.

RESULTS

Of 7886 citations, we included 50 articles. Commonly evaluated interventions include care bundles (n=20), regulation or administration of light therapy (n=5), eye masks and/or earplugs (n=5), one nursing care-focused intervention and pharmacological intervention (eg, melatonin and ramelteon; n=19). The association between these interventions and incident delirium or severity of delirium was mixed. As multiple interventions were incorporated in included studies of care bundles and given that there was variable reporting of compliance with individual elements, identifying which components might have an impact on delirium is challenging.

CONCLUSIONS

This scoping review summarises the existing literature as it relates to ICU sleep and circadian disruption (SCD) and delirium in ICU. Further studies are needed to better understand the role of ICU SCD promotion interventions in delirium mitigation.

Causes, Consequences, and Treatments of Sleep and Circadian Disruption in the ICU: An Official American Thoracic Society Research Statement

Background: Sleep and circadian disruption (SCD) is common and severe in the ICU. On the basis of rigorous evidence in non-ICU populations and emerging evidence in ICU populations, SCD is likely to have a profound negative impact on patient outcomes. Thus, it is urgent that we establish research priorities to advance understanding of ICU SCD. Methods: We convened a multidisciplinary group with relevant expertise to participate in an American Thoracic Society Workshop. Workshop objectives included identifying ICU SCD subtopics of interest, key knowledge gaps, and research priorities. Members attended remote sessions from March to November 2021. Recorded presentations were prepared and viewed by members before Workshop sessions. Workshop discussion focused on key gaps and related research priorities. The priorities listed herein were selected on the basis of rank as established by a series of anonymous surveys. Results: We identified the following research priorities: establish an ICU SCD definition, further develop rigorous and feasible ICU SCD measures, test associations between ICU SCD domains and outcomes, promote the inclusion of mechanistic and patient-centered outcomes within large clinical studies, leverage implementation science strategies to maximize intervention fidelity and sustainability, and collaborate among investigators to harmonize methods and promote multisite investigation. Conclusions: ICU SCD is a complex and compelling potential target for improving ICU outcomes. Given the influence on all other research priorities, further development of rigorous, feasible ICU SCD measurement is a key next step in advancing the field.

Study protocol for a randomized controlled trial of Proportional Assist Ventilation for Minimizing the Duration of Mechanical Ventilation: the PROMIZING study

BACKGROUND

Proportional assist ventilation with load-adjustable gain factors (PAV+) is a mechanical ventilation mode that delivers assistance to breathe in proportion to the patient's effort. The proportional assistance, called the gain, can be adjusted by the clinician to maintain the patient's respiratory effort or workload within a normal range. Short-term and physiological benefits of this mode compared to pressure support ventilation (PSV) include better patient-ventilator synchrony and a more physiological response to changes in ventilatory demand.

METHODS

The objective of this multi-centre randomized controlled trial (RCT) is to determine if, for patients with acute respiratory failure, ventilation with PAV+ will result in a shorter time to successful extubation than with PSV. This multi-centre open-label clinical trial plans to involve approximately 20 sites in several continents. Once eligibility is determined, patients must tolerate a short-term PSV trial and either (1) not meet general weaning criteria or (2) fail a 2-min Zero Continuous Positive Airway Pressure (CPAP) Trial using the rapid shallow breathing index, or (3) fail a spontaneous breathing trial (SBT), in this sequence. Then, participants in this study will be randomized to either PSV or PAV+ in a 1:1 ratio. PAV+ will be set according to a target of muscular pressure. The weaning process will be identical in the two arms. Time to liberation will be the primary outcome; ventilator-free days and other outcomes will be measured.

DISCUSSION

Meta-analyses comparing PAV+ to PSV suggest PAV+ may benefit patients and decrease healthcare costs but no powered study to date has targeted the difficult to wean patient population most likely to benefit from the intervention, or used consistent timing for the implementation of PAV+. Our enrolment strategy, primary outcome measure, and liberation approaches may be useful for studying mechanical ventilation and weaning and can offer important results for patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02447692 . Prospectively registered on May 19, 2015.

Association of Extracorporeal Membrane Oxygenation With New Mental Health Diagnoses in Adult Survivors of Critical Illness

IMPORTANCE

Extracorporeal membrane oxygenation (ECMO) is used as temporary cardiorespiratory support in critically ill patients, but little is known regarding long-term psychiatric sequelae among survivors after ECMO.

OBJECTIVE

To investigate the association between ECMO survivorship and postdischarge mental health diagnoses among adult survivors of critical illness.

DESIGN, SETTING, AND PARTICIPANTS

Population-based retrospective cohort study in Ontario, Canada, from April 1, 2010, through March 31, 2020. Adult patients (N=4462; age ≥18 years) admitted to the intensive care unit (ICU), and surviving to hospital discharge were included.

EXPOSURES

Receipt of ECMO.

MAIN OUTCOMES AND MEASURES

The primary outcome was a new mental health diagnosis (a composite of mood disorders, anxiety disorders, posttraumatic stress disorder; schizophrenia, other psychotic disorders; other mental health disorders; and social problems) following discharge. There were 8 secondary outcomes including incidence of substance misuse, deliberate self-harm, death by suicide, and individual components of the composite primary outcome. Patients were compared with ICU survivors not receiving ECMO using overlap propensity score-weighted cause-specific proportional hazard models.

RESULTS

Among 642 survivors who received ECMO (mean age, 50.7 years; 40.7% female), median length of follow-up was 730 days; among 3820 matched ICU survivors who did not receive ECMO (mean age, 51.0 years; 40.0% female), median length of follow-up was 1390 days. Incidence of new mental health conditions among survivors who received ECMO was 22.1 per 100-person years (95% confidence interval [CI] 19.5-25.1), and 14.5 per 100-person years (95% CI, 13.8-15.2) among non-ECMO ICU survivors (absolute rate difference of 7.6 per 100-person years [95% CI, 4.7-10.5]). Following propensity weighting, ECMO survivorship was significantly associated with an increased risk of new mental health diagnosis (hazard ratio [HR] 1.24 [95% CI, 1.01-1.52]). There were no significant differences between survivors who received ECMO vs ICU survivors who did not receive ECMO in substance misuse (1.6 [95% CI, 1.1 to 2.4] per 100 person-years vs 1.4 [95% CI, 1.2 to 1.6] per 100 person-years; absolute rate difference, 0.2 per 100 person-years [95% CI, -0.4 to 0.8]; HR, 0.86 [95% CI, 0.48 to 1.53]) or deliberate self-harm (0.4 [95% CI, 0.2 to 0.9] per 100 person-years vs 0.3 [95% CI, 0.2 to 0.3] per 100 person-years; absolute rate difference, 0.1 per 100 person-years [95% CI, -0.2 to 0.4]; HR, 0.68 [95% CI, 0.21 to 2.23]). There were fewer than 5 total cases of death by suicide in the entire cohort.

CONCLUSIONS AND RELEVANCE

Among adult survivors of critical illness, receipt of ECMO, compared with ICU hospitalization without ECMO, was significantly associated with a modestly increased risk of new mental health diagnosis or social problem diagnosis after discharge. Further research is necessary to elucidate the potential mechanisms underlying this relationship.

Sleep in the intensive care unit

PURPOSE OF REVIEW

Sleep is particularly important for critically ill patients. Here, we review the latest evidence on how sleep and circadian disruption in the intensive care unit (ICU) affects physiology and clinical outcomes, as well as the most recent advances in sleep and circadian rhythm promoting interventions including therapeutics.

RECENT FINDINGS

On a molecular level, clock genes dysrhythmia and altered immunity are clearly linked, particularly in sepsis. Melatonin may also be associated with insulin sensitivity in ICU patients. Clinically, changes in sleep architecture are associated with delirium, and sleep-promoting interventions in the form of multifaceted care bundles may reduce its incidence. Regarding medications, one recent randomized controlled trial (RCT) on melatonin showed no difference in sleep quality or incidence of delirium.

SUMMARY

Further investigation is needed to establish the clinical relevance of sleep and circadian disruption in the ICU. For interventions, standardized protocols of sleep promotion bundles require validation by larger multicenter trials. Administratively, such protocols should be individualized to both organizational and independent patient needs. Incorporating pharmacotherapy such as melatonin and nocturnal dexmedetomidine requires further evaluation in large RCTs.

Health-related quality-of-life and health-utility reporting in critical care

Mortality is a well-established patient-important outcome in critical care studies. In contrast, morbidity is less uniformly reported (given the myriad of critical care illnesses and complications of each) but may have a common end-impact on a patient’s functional capacity and health-related quality-of-life (HRQoL). Survival with a poor quality-of-life may not be acceptable depending on individual patient values and preferences. Hence, as mortality decreases within critical care, it becomes increasingly important to measure intensive care unit (ICU) survivor HRQoL. HRQoL measurements with a preference-based scoring algorithm can be converted into health utilities on a scale anchored at 0 (representing death) and 1 (representing full health). They can be combined with survival to calculate quality-adjusted life-years (QALY), which are one of the most widely used methods of combining morbidity and mortality into a composite outcome. Although QALYs have been use for health-technology assessment decision-making, an emerging and novel role would be to inform clinical decision-making for patients, families and healthcare providers about what expected HRQoL may be during and after ICU care. Critical care randomized control trials (RCTs) have not routinely measured or reported HRQoL (until more recently), likely due to incapacity of some patients to participate in patient-reported outcome measures. Further differences in HRQoL measurement tools can lead to non-comparable values. To this end, we propose the validation of a gold-standard HRQoL tool in critical care, specifically the EQ-5D-5L. Both combined health-utility and mortality (disaggregated) and QALYs (aggregated) can be reported, with disaggregation allowing for determination of which components are the main drivers of the QALY outcome. Increased use of HRQoL, health-utility, and QALYs in critical care RCTs has the potential to: (1) Increase the likelihood of finding important effects if they exist; (2) improve research efficiency; and (3) help inform optimal management of critically ill patients allowing for decision-making about their HRQoL, in additional to traditional health-technology assessments.

Protocol for a scoping review of sepsis epidemiology

INTRODUCTION

Sepsis is a common, life-threatening syndrome of physiologic, pathologic, and biochemical abnormalities that are caused by infection and propagated by a dysregulated immune response. In 2017, the estimated annual incidence of sepsis around the world was 508 cases per 100,000 (95% confidence interval [CI], 422-612 cases per 100,000), however, reported incidence rates vary significantly by country. A scoping review will identify knowledge gaps by systematically investigating the incidence of sepsis.

METHODS AND ANALYSIS

This scoping review will be guided by the updated JBI (formerly Joanna Briggs Institute) methodology. We will search the following electronic databases: MEDLINE, EMBASE, CINAHL, and Cochrane Database of Systematic Reviews/Central Register of Controlled Trials. In addition, we will search websites of trial and study registries. We will review titles and abstracts of potentially eligible studies and then full-texts by two independent reviewers. We will include any study that is focused on the incidence of sepsis or septic shock in any population. Data will be abstracted independently using pre-piloted data extraction forms, and we will present results according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis Protocols Extension for Scoping Reviews.

ETHICS AND DISSEMINATION

The results of this review will be used to create a publicly available indexed and searchable electronic registry of existing sepsis research relating to incidence in neonates, children, and adults. With input from stakeholders, we will identify the implications of study findings for policy, practice, and research. Ethics approval was not required given this study reports on existing literature.

Prophylactic acid suppressants in patients with primary neurologic injury: A systematic review and meta-analysis of randomized controlled trials

PURPOSE

Neurocritical care patients are at risk of stress-induced gastrointestinal ulceration. We performed a systematic review and meta-analysis of stress ulcer prophylaxis (SUP) in critically ill adults admitted with a primary neurologic injury.

MATERIALS AND METHODS

We included randomized controlled trials (RCTs) comparing SUP with histamine-2-receptor antagonists (H2RAs) or proton pump inhibitors (PPIs) to placebo/no prophylaxis, as well as to each other. The primary outcome was in-ICU gastrointestinal bleeding (GIB). Predefined secondary outcomes were all-cause 30-day mortality, ICU length of stay (LOS), nosocomial pneumonia, and other complications.

RESULTS

We identified 14 relevant trials enrolling 1036 neurocritical care patients; 11 trials enrolling 930 patients were included in the meta-analysis. H2RAs resulted in a lower incidence of GIB as compared to placebo or no prophylaxis (Risk ratio [RR] 0.42, 95% CI 0.30-0.58; p < 0.001); PPIs with a lower risk of GIB compared to placebo/no prophylaxis (RR 0.37, 95% CI 0.23-0.59; p < 0.001). No significant difference was observed in GIB comparing PPIs with H2RAs (RR 0.53, 95% CI 0.26-1.06; p = 0.07; I² = 0%).

CONCLUSIONS

In neurocritical care patients, the overall high or unclear risk of bias of individual trials, the low event rates, and modest sample sizes preclude strong clinical inferences about the utility of SUP.

Development of a repeated-measures predictive model and clinical risk score for mortality in ventilated COVID-19 patients

PURPOSE

The COVID-19 pandemic has caused intensive care units (ICUs) to reach capacities requiring triage. A tool to predict mortality risk in ventilated patients with COVID-19 could inform decision-making and resource allocation, and allow population-level comparisons across institutions.

METHODS

This retrospective cohort study included all mechanically ventilated adults with COVID-19 admitted to three tertiary care ICUs in Toronto, Ontario, between 1 March 2020 and 15 December 2020. Generalized estimating equations were used to identify variables predictive of mortality. The primary outcome was the probability of death at three-day intervals from the time of ICU admission (day 0), with risk re-calculation every three days to day 15; the final risk calculation estimated the probability of death at day 15 and beyond. A numerical algorithm was developed from the final model coefficients.

RESULTS

One hundred twenty-seven patients were eligible for inclusion. Median ICU length of stay was 26.9 (interquartile range, 15.4-52.0) days. Overall mortality was 42%. From day 0 to 15, the variables age, temperature, lactate level, ventilation tidal volume, and vasopressor use significantly predicted mortality. Our final clinical risk score had an area under the receiver-operating characteristics curve of 0.9 (95% confidence interval [CI], 0.8 to 0.9). For every ten-point increase in risk score, the relative increase in the odds of death was approximately 4, with an odds ratio of 4.1 (95% CI, 2.9 to 5.9).

CONCLUSION

Our dynamic prediction tool for mortality in ventilated patients with COVID-19 has excellent diagnostic properties. Notwithstanding, external validation is required before widespread implementation.

The evolution of mean arterial pressure in critically ill patients on vasopressors before and during a trial comparing a specific mean arterial pressure target to usual care

Background

In randomized clinical controlled trials, the choice of usual care as the comparator may be associated with better clinician uptake of the study protocol and lead to more generalizable results. However, if care processes evolve to resemble the intervention during the course of a trial, differences between the intervention group and usual care control group may narrow. We evaluated the effect on mean arterial pressure of an unblinded trial comparing a lower mean arterial pressure target to reduce vasopressor exposure, vs. a clinician-selected mean arterial pressure target, in critically ill patients at least 65 years old.

Methods

For this multicenter observational study using data collected both prospectively and retrospectively, patients were recruited from five of the seven trial sites. We compared the mean arterial pressure of patients receiving vasopressors, who met or would have met trial eligibility criteria, from two periods: [1] at least 1 month before the trial started, and [2] during the trial period and randomized to usual care, or not enrolled in the trial.

Results

We included 200 patients treated before and 229 after trial initiation. There were no differences in age (mean 74.5 vs. 75.2 years; p = 0.28), baseline Acute Physiology and Chronic Health Evaluation II score (median 26 vs. 26; p = 0.47) or history of chronic hypertension (n = 126 [63.0%] vs. n = 153 [66.8%]; p = 0.41). Mean of the mean arterial pressure was similar between the two periods (72.5 vs. 72.4 mmHg; p = 0.76).

Conclusions

The initiation of a trial of a prescribed lower mean arterial pressure target, compared to a usual clinician-selected target, was not associated with a change in mean arterial pressure, reflecting stability in the net effect of usual clinician practices over time. Comparing prior and concurrent control groups may alleviate concerns regarding drift in usual practices over the course of a trial or permit quantification of any change.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01529-w.

Effect of Probiotics on Incident Ventilator-Associated Pneumonia in Critically Ill Patients: A Randomized Clinical Trial

IMPORTANCE

Growing interest in microbial dysbiosis during critical illness has raised questions about the therapeutic potential of microbiome modification with probiotics. Prior randomized trials in this population suggest that probiotics reduce infection, particularly ventilator-associated pneumonia (VAP), although probiotic-associated infections have also been reported.

OBJECTIVE

To evaluate the effect of Lactobacillus rhamnosus GG on preventing VAP, additional infections, and other clinically important outcomes in the intensive care unit (ICU).

DESIGN, SETTING, AND PARTICIPANTS

Randomized placebo-controlled trial in 44 ICUs in Canada, the United States, and Saudi Arabia enrolling adults predicted to require mechanical ventilation for at least 72 hours. A total of 2653 patients were enrolled from October 2013 to March 2019 (final follow-up, October 2020).

INTERVENTIONS

Enteral L rhamnosus GG (1 × 1010 colony-forming units) (n = 1321) or placebo (n = 1332) twice daily in the ICU.

MAIN OUTCOMES AND MEASURES

The primary outcome was VAP determined by duplicate blinded central adjudication. Secondary outcomes were other ICU-acquired infections including Clostridioides difficile infection, diarrhea, antimicrobial use, ICU and hospital length of stay, and mortality.

RESULTS

Among 2653 randomized patients (mean age, 59.8 years [SD], 16.5 years), 2650 (99.9%) completed the trial (mean age, 59.8 years [SD], 16.5 years; 1063 women [40.1%.] with a mean Acute Physiology and Chronic Health Evaluation II score of 22.0 (SD, 7.8) and received the study product for a median of 9 days (IQR, 5-15 days). VAP developed among 289 of 1318 patients (21.9%) receiving probiotics vs 284 of 1332 controls (21.3%; hazard ratio [HR], 1.03 (95% CI, 0.87-1.22; P = .73, absolute difference, 0.6%, 95% CI, -2.5% to 3.7%). None of the 20 prespecified secondary outcomes, including other ICU-acquired infections, diarrhea, antimicrobial use, mortality, or length of stay showed a significant difference. Fifteen patients (1.1%) receiving probiotics vs 1 (0.1%) in the control group experienced the adverse event of L rhamnosus in a sterile site or the sole or predominant organism in a nonsterile site (odds ratio, 14.02; 95% CI, 1.79-109.58; P < .001).

CONCLUSIONS AND RELEVANCE

Among critically ill patients requiring mechanical ventilation, administration of the probiotic L rhamnosus GG compared with placebo, resulted in no significant difference in the development of ventilator-associated pneumonia. These findings do not support the use of L rhamnosus GG in critically ill patients.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02462590.

Delirium and long term cognition in critically ill patients

Delirium, a form of acute brain dysfunction, is very common in the critically ill adult patient population. Although its pathophysiology is poorly understood, multiple factors associated with delirium have been identified, many of which are coincident with critical illness. To date, no drug or non-drug treatments have been shown to improve outcomes in patients with delirium. Clinical trials have provided a limited understanding of the contributions of multiple triggers and processes of intensive care unit (ICU) acquired delirium, making identification of therapies difficult. Delirium is independently associated with poor long term outcomes, including persistent cognitive impairment. A longer duration of delirium is associated with worse long term cognition after adjustment for age, education, pre-existing cognitive function, severity of illness, and exposure to sedatives. Interestingly, differences in prevalence are seen between ICU survivor populations, with survivors of acute respiratory distress syndrome experiencing higher rates of cognitive impairment at early follow-up compared with mixed ICU survivor populations. Although cognitive performance improves over time for some ICU survivors, impairment is persistent in others. Studies have so far been unable to identify patients at higher risk of long term cognitive impairment; this is an active area of scientific investigation.

Health-Related Quality-of-Life and Cost Utility Analyses in Critical Care: A Systematic Review

OBJECTIVES

Cost utility analyses compare the costs and health outcome of interventions, with a denominator of quality-adjusted life year, a generic health utility measure combining both quality and quantity of life. Cost utility analyses are difficult to compare when methods are not standardized. It is unclear how cost utility analyses are measured/reported in critical care and what methodologic challenges cost utility analyses pose in this setting. This may lead to differences precluding cost utility analyses comparisons. Therefore, we performed a systematic review of cost utility analyses conducted in critical care. Our objectives were to understand: 1) methodologic characteristics, 2) how health-related quality-of-life was measured/reported, and 3) what costs were reported/measured.

DESIGN

Systematic review.

DATA SOURCES

We systematically searched for cost utility analyses in critical care in MEDLINE, Embase, American College of Physicians Journal Club, CENTRAL, Evidence-Based Medicine Reviews' selected subset of archived versions of UK National Health Service Economic Evaluation Database, Database of Abstracts of Reviews of Effects, and American Economic Association electronic databases from inception to April 30, 2020.

SETTING

Adult ICUs.

PATIENTS

Adult critically ill patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 8,926 citations, 80 cost utility analyse studies were eligible. The time horizon most commonly reported was lifetime (59%). For health utility reporting, health-related quality-of-life was infrequently measured (29% reported), with only 5% of studies reporting baseline health-related quality-of-life. Indirect utility measures (generic, preference-based health utility measurement tools) were reported in 85% of studies (majority Euro-quality-of-life-5 Domains, 52%). Methods of estimating health-related quality-of-life were seldom used when the patient was incapacitated: imputation (19%), assigning fixed utilities for incapacitation (19%), and surrogates reporting on behalf of incapacitated patients (5%). For cost utility reporting transparency, separate incremental costs and quality-adjusted life years were both reported in only 76% of studies. Disaggregated quality-adjusted life years (reporting separate health utility and life years) were described in only 34% of studies.

CONCLUSIONS

We identified deficiencies which warrant recommendations (standardized measurement/reporting of resource use/unit costs/health-related quality-of-life/methodological preferences) for improved design, conduct, and reporting of future cost utility analyses in critical care.

Abnormal Sleep, Circadian Rhythm Disruption, and Delirium in the ICU: Are They Related?

Delirium is a syndrome characterized by acute brain failure resulting in neurocognitive disturbances affecting attention, awareness, and cognition. It is highly prevalent among critically ill patients and is associated with increased morbidity and mortality. A core domain of delirium is represented by behavioral disturbances in sleep-wake cycle probably related to circadian rhythm disruption. The relationship between sleep, circadian rhythm and intensive care unit (ICU)-acquired delirium is complex and likely bidirectional. In this review, we explore the proposed pathophysiological mechanisms of sleep disruption and circadian dysrhythmia as possible contributing factors in transitioning to delirium in the ICU and highlight some of the most relevant caveats for understanding the relationship between these complex phenomena. Specifically, we will (1) review the physiological consequences of poor sleep quality and efficiency; (2) explore how the neural substrate underlying the circadian clock functions may be disrupted in delirium; (3) discuss the role of sedative drugs as contributors to delirium and chrono-disruption; and, (4) describe the association between abnormal sleep-pathological wakefulness, circadian dysrhythmia, delirium and critical illness. Opportunities to improve sleep and readjust circadian rhythmicity to realign the circadian clock may exist as therapeutic targets in both the prevention and treatment of delirium in the ICU. Further research is required to better define these conditions and understand the underlying physiologic relationship to develop effective prevention and therapeutic strategies.

Correction to: Understanding gender disparities in outcomes after sepsis

The original version of this article unfortunately contained a mistake. There was an error in figure one. The correct figure can be found below. We apologize for the mistake.

Challenges in conducting long-term outcomes studies in critical care

PURPOSE OF REVIEW

Evaluating longer term mortality, morbidity, and quality of life in survivors of critical illness is a research priority. This review details the challenges of long-term follow-up studies of critically ill patients and highlights recently proposed methodological solutions.

RECENT FINDINGS

Barriers to long-term follow-up studies of critical care survivors include high rates of study attrition because of death or loss to follow-up, data missingness from experienced morbidity, and lack of standardized outcome as well as reporting of key covariates. A number of recent methods have been proposed to reduce study patients attrition, including minimum data set selection and visits to transitional care or home settings, yet these have significant downsides as well. Conducting long-term follow-up even in the absence of such models carries a high expense, as personnel are very costly, and patients/families require reimbursement for their time and inconvenience.

SUMMARY

There is a reason why many research groups do not conduct long-term outcomes in critical care: it is very difficult. Challenges of long-term follow-up require careful consideration by study investigators to ensure our collective success in data integration and a better understanding of underlying mechanisms of mortality and morbidity seen in critical care survivorship.

Models of Peer Support to Remediate Post-Intensive Care Syndrome: A Report Developed by the Society of Critical Care Medicine Thrive International Peer Support Collaborative

OBJECTIVES

Patients and caregivers can experience a range of physical, psychologic, and cognitive problems following critical care discharge. The use of peer support has been proposed as an innovative support mechanism.

DESIGN

We sought to identify technical, safety, and procedural aspects of existing operational models of peer support, among the Society of Critical Care Medicine Thrive Peer Support Collaborative. We also sought to categorize key distinctions between these models and elucidate barriers and facilitators to implementation.

SUBJECTS AND SETTING

Seventeen Thrive sites from the United States, United Kingdom, and Australia were represented by a range of healthcare professionals.

MEASUREMENTS AND MAIN RESULTS

Via an iterative process of in-person and email/conference calls, members of the Collaborative defined the key areas on which peer support models could be defined and compared, collected detailed self-reports from all sites, reviewed the information, and identified clusters of models. Barriers and challenges to implementation of peer support models were also documented. Within the Thrive Collaborative, six general models of peer support were identified: community based, psychologist-led outpatient, models-based within ICU follow-up clinics, online, groups based within ICU, and peer mentor models. The most common barriers to implementation were recruitment to groups, personnel input and training, sustainability and funding, risk management, and measuring success.

CONCLUSIONS

A number of different models of peer support are currently being developed to help patients and families recover and grow in the postcritical care setting.

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.

Long-Term Quality of Life After Extracorporeal Membrane Oxygenation in ARDS Survivors: Systematic Review and Meta-Analysis

PURPOSE

Extracorporeal membrane oxygenation (ECMO) is an increasingly prevalent treatment for acute respiratory failure (ARF). To evaluate the impact of ECMO support on long-term outcomes for critically ill adults with ARF.

METHODS

We searched electronic databases 1948 through to November 30 2016; selected controlled trials or observational studies of critically ill adults with acute respiratory distress syndrome, examining long-term morbidity specifically health-related quality of life (HRQL); 2 authors independently selected studies, extracted data, and assessed methodological quality.

ANALYSIS

Of the 633 citations, 1 randomized controlled trial and 5 observational studies met the selection criteria. Overall quality of observational studies was moderate to high (mean score on Newcastle-Ottawa scale, 7.2/9; range, 6-8). In 3 studies (n = 245), greater decrements in HRQL were seen for survivors of ECMO when compared to survivors of conventional mechanical ventilation (CMV) as measured by the Short Form 36 (SF-36) scores ([ECMO-CMV]: 5.40 [95% confidence interval, CI, 4.11 to 6.68]). As compared to CMV survivors, those who received ECMO experienced significantly less psychological morbidity (2 studies; n = 217 [ECMO-CMV]: mean weighted difference [MWD], -1.31 [95% CI, -1.98 to -0.64] for depression and MWD, -1.60 [95% CI, -1.80 to -1.39] for anxiety).

CONCLUSIONS

Further studies are required to confirm findings and determine prognostic factors associated with more favorable outcomes in survivors of ECMO.

An Official American Thoracic Society Systematic Review: The Effect of Nighttime Intensivist Staffing on Mortality and Length of Stay among Intensive Care Unit Patients

BACKGROUND

Studies of nighttime intensivist staffing have yielded mixed results.

GOALS

To review the association of nighttime intensivist staffing with outcomes of intensive care unit (ICU) patients.

METHODS

We searched five databases (2000-2016) for studies comparing in-hospital nighttime intensivist staffing with other nighttime staffing models in adult ICUs and reporting mortality or length of stay. We abstracted data on staffing models, outcomes, and study characteristics and assessed study quality, using standardized tools. Meta-analyses used random effects models.

RESULTS

Eighteen studies met inclusion criteria: one randomized controlled trial and 17 observational studies. Overall methodologic quality was high. Studies included academic hospitals (n = 10), community hospitals (n = 2), or both (n = 6). Baseline clinician staffing included residents (n = 9), fellows (n = 4), and nurse practitioners or physician assistants (n = 2). Studies included both general and specialty ICUs and were geographically diverse. Meta-analysis (one randomized controlled trial; three nonrandomized studies with exposure limited to nighttime intensivist staffing with adjusted estimates of effect) demonstrated no association with mortality (odds ratio, 0.99; 95% confidence interval, 0.75-1.29). Secondary analyses including studies without risk adjustment, with a composite exposure of organizational factors, stratified by intensity of daytime staffing and by ICU type, yielded similar results. Minimal or no differences were observed in ICU and hospital length of stay and several other secondary outcomes.

CONCLUSIONS

Notwithstanding limitations of the predominantly observational evidence, our systematic review and meta-analysis suggests nighttime intensivist staffing is not associated with reduced ICU patient mortality. Other outcomes and alternative staffing models should be evaluated to further guide staffing decisions.

A study protocol for an observational cohort investigating COGnitive outcomes and WELLness in survivors of critical illness: the COGWELL study

INTRODUCTION

Up to 9 out of 10 intensive care unit (ICU) survivors will suffer some degree of cognitive impairment at hospital discharge and approximately half will have decrements that persist for years. The mechanisms for this newly acquired brain injury are poorly understood. The purpose of this study is to describe the prevalence of sleep abnormalities and their association with cognitive impairment, examine a well-known genetic risk factor for dementia (Apolipoprotein E ε4) that may allow for genetic risk stratification of ICU survivors at greatest risk of cognitive impairment and determine if electroencephalography (EEG) is an independent predictor of long-term cognitive impairment and possibly a candidate intermediate end point for future clinical trials.

METHODS AND ANALYSIS

This is a multisite, prospective, observational cohort study. The setting for this trial will be medical and surgical ICUs of five large tertiary care referral centres. The participants will be adult patients admitted to a study ICU and invasively ventilated for ≥3 days . Participants will undergo follow-up within 7 days of ICU discharge, 6 months and 1 year. At each time point, patients will have an EEG, blood work (biomarkers; gene studies), sleep study (actigraphy), complete a number of questionnaires as well as undergo neuropsychological testing. The primary outcome of this study will be long-term cognitive function at 12 months follow-up as measured by the Repeatable Battery for the Assessment of Neuropsychological Status and Trails Making Test B.

ETHICS AND DISSEMINATION

The study has received the following approvals: University Health Network Research Ethics Committee (13-6425-BE), Sunnybrook Health Centre Research Ethics Committee (365-2013), Mount Sinai Research Ethics Committee (14-0194-E) and St. Michael's Hospital Research Ethics Committee (14-295). Results will be made available to critical care survivors, their caregivers, the funders, the critical care societies and other researchers.

TRIAL REGISTRATION NUMBER

NCT02086877; Pre-results.

Association of Intensive Care Unit Patient-to-Intensivist Ratios With Hospital Mortality

IMPORTANCE

The patient-to-intensivist ratio (PIR) across intensive care units (ICUs) is not standardized and the association of PIR with patient outcome is not well established. Understanding the impact of PIR on outcomes is necessary to optimize senior medical staffing and deliver high-quality care.

OBJECTIVE

To test the hypotheses that: (1) there is significant variation in the PIR across ICUs and (2) higher PIRs are associated with higher hospital mortality for ICU patients.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort analysis of patients (≥16 years) admitted to ICUs staffed by a single intensivist during daytime hours in the United Kingdom from 2010 to 2013.

EXPOSURES

Patient-to-intensivist ratios, which we defined for each patient as the number of patients cared for by the intensivist each day averaged over the patient's stay.

MAIN OUTCOMES AND MEASURES

Using standard summary statistics, we evaluated PIR variation across ICUs. We used multivariable, mixed-effect, logistic regression analysis to evaluate the association between PIR and hospital mortality at ultimate discharge from acute hospital (primary outcome) and at ICU discharge.

FINDING

Among 49 686 adults in 94 ICUs, median age was 66 (interquartile range [IQR], 52-76) years, and 45.1% were women. The ultimate hospital mortality was 25.7%. The median PIR for patients was 8.5 (IQR, 6.9-10.8; full range, 1.0-23.5), and varied substantially among individual ICUs. The association between PIR and ultimate hospital mortality was U-shaped; there was a reduction in the odds of mortality associated with an increasing PIR up to 7.5 after which the odds of mortality increased again significantly (average patient mortality for lowest PIR, 22%; PIR of 7.5, 15%; highest PIR, 19%; P = .003). A similar U-shaped association was seen for PIR and mortality in the ICU (nadir of mortality at a PIR of 7.8, P < .001).

CONCLUSIONS AND RELEVANCE

PIR varied across UK ICUs. The optimal PIR in this cohort of UK ICU patients was 7.5, with significantly increased ICU and hospital mortality above and below this ratio. The number of patients cared for by 1 intensivist may impact patient outcomes.

Critical Illness-Associated Cerebral Microbleeds

BACKGROUND AND PURPOSE

Cerebral microbleeds (petechial hemorrhages) are a well-known consequence of cerebral amyloid angiopathy and chronic hypertension among other causes. We report 12 patients with a clinically and radiologically distinct microbleed phenomenon in the cerebral white matter.

METHODS

These patients were assessed at the University Health Network (Toronto, Canada) between 2004 and 2014.

RESULTS

Median age was 40 years (range, 27-63 years), and 7 out of 12 patients were women. All patients had brain magnetic resonance imaging during or immediately after an intensive care unit admission. All patients had respiratory failure, 11 out of 12 received mechanical ventilation, and 3 out of 12 received extracorporeal life support. Magnetic resonance imaging in all 12 patients showed extensive microbleeds, diffusely involving the juxtacortical white matter and corpus callosum but sparing the cortex, deep and periventricular white matter, basal ganglia, and thalami. Several patients also had internal capsule or posterior fossa involvement.

CONCLUSIONS

We have described a distinct microbleed phenomenon in the cerebral white matter of patients with critical illness. The specific cause of the microbleeds is unclear, but the pathogenesis may involve hypoxemia as the microbleeds are similar to those described with high-altitude exposure.

The RECOVER Program: Disability Risk Groups and 1-Year Outcome after 7 or More Days of Mechanical Ventilation

RATIONALE

Disability risk groups and 1-year outcome after greater than or equal to 7 days of mechanical ventilation (MV) in medical/surgical intensive care unit (ICU) patients are unknown and may inform education, prognostication, rehabilitation, and study design.

OBJECTIVES

To stratify patients for post-ICU disability and recovery to 1 year after critical illness.

METHODS

We evaluated a multicenter cohort of 391 medical/surgical ICU patients who received greater than or equal to 1 week of MV at 7 days and 3, 6, and 12 months after ICU discharge. Disability risk groups were identified using recursive partitioning modeling.

MEASUREMENTS AND MAIN RESULTS

The 7-day post-ICU Functional Independence Measure (FIM) determined the recovery trajectory to 1-year after ICU discharge and was an independent risk factor for 1-year mortality. The 7-day post-ICU FIM was predicted by age and ICU length of stay. By 2 weeks of MV, ICU patients could be stratified into four disability groups characterized by increasing risk for post ICU disability, ICU and post-ICU healthcare use, and disposition. Patients less than 42 years with ICU length of stay less than 2 weeks had the best function and fewest deaths at 1 year compared with patients greater than 66 years with ICU length of stay greater than 2 weeks who sustained the worst disability and 40% 1-year mortality. Depressive symptoms (17%) and post-traumatic stress disorder (18%) persisted at 1 year.

CONCLUSIONS

ICU survivors of greater than or equal to 1 week of MV may be stratified into four disability groups based on age and ICU length of stay. These groups determine 1-year recovery and healthcare use and are independent of admitting diagnosis and illness severity. Clinical trial registered with www.clinicaltrials.gov (NCT 00896220).

Depressive symptoms and functional decline following coronary interventions in older patients with coronary artery disease: a prospective cohort study

BACKGROUND

Depressive symptoms are prevalent in patients with coronary artery disease (CAD). It is unclear, however, how depressive symptoms change over time and the impact of these changes on long-term functional outcomes. We examined the association between different trajectories of depressive symptoms over 1 year and change in functional status over 30 months among patients undergoing coronary angiography.

METHODS

This was a prospective cohort study of 350 patients aged 60 and older undergoing non-emergent cardiac catheterization (October 2003-February 2007). A dynamic measure of significant depressive symptoms (i.e., Geriatric Depression Scale score 5+) capturing change over 12 months was derived that categorized patients into the following groups: (i) no clinically important depressive symptoms (at baseline, 6 and 12 months); (ii) baseline-only symptoms (at baseline but not at 6 and 12 months); (iii) new onset symptoms (not at baseline but present at either 6 or 12 months); and, (iv) persistent symptoms (at baseline and at either 6 or 12 month assessment). Primary outcomes were mean change in Older Americans Resources and Services (OARS) instrumental (IADL) and basic activities of daily living (BADL) scores (range 0-14 for each) across baseline (pre-procedure) and 6, 12, and 30 months post-procedure visits.

RESULTS

Estimates for the symptom categories were 71 % (none), 9 % (baseline only), 8 % (new onset) and 12 % (persistent). In adjusted models, patients with persistent symptoms showed a significant decrease in mean IADL and BADL scores from baseline to 6 months (-1.32 [95 % CI -1.78 to -0.86] and -0.63 [-0.97 to -0.30], respectively) and from 12 to 30 months (-0.79 [-1.27 to -0.31] and -1.00 [-1.35 to -0.65], respectively). New onset symptoms were associated with a significant decrease in mean IADL scores at 6 months and from 6 to 12 months. Patients with no depressive symptoms showed little change in scores whereas those with baseline only symptoms showed significant improvement in mean IADL at 6 months.

CONCLUSIONS

Patients with persistent depressive symptoms were at greatest risk for worse functional status 30 months following coronary interventions. Proactive screening and follow-up for depression in this population offers prognostic value and may facilitate the implementation of targeted interventions.

One-Year Outcomes in Caregivers of Critically Ill Patients

BACKGROUND

Few resources are available to support caregivers of patients who have survived critical illness; consequently, the caregivers' own health may suffer. We studied caregiver and patient characteristics to determine which characteristics were associated with caregivers' health outcomes during the first year after patient discharge from an intensive care unit (ICU).

METHODS

We prospectively enrolled 280 caregivers of patients who had received 7 or more days of mechanical ventilation in an ICU. Using hospital data and self-administered questionnaires, we collected information on caregiver and patient characteristics, including caregiver depressive symptoms, psychological well-being, health-related quality of life, sense of control over life, and effect of providing care on other activities. Assessments occurred 7 days and 3, 6, and 12 months after ICU discharge.

RESULTS

The caregivers' mean age was 53 years, 70% were women, and 61% were caring for a spouse. A large percentage of caregivers (67% initially and 43% at 1 year) reported high levels of depressive symptoms. Depressive symptoms decreased at least partially with time in 84% of the caregivers but did not in 16%. Variables that were significantly associated with worse mental health outcomes in caregivers were younger age, greater effect of patient care on other activities, less social support, less sense of control over life, and less personal growth. No patient variables were consistently associated with caregiver outcomes over time.

CONCLUSIONS

In this study, most caregivers of critically ill patients reported high levels of depressive symptoms, which commonly persisted up to 1 year and did not decrease in some caregivers. (Funded by the Canadian Institutes of Health Research and others; ClinicalTrials.gov number, NCT00896220.).

Is critical care ready for an economic surrogate endpoint?

Intensive care is expensive, and thus a body of research has focused on strategies to reduce its costs. However, efforts to reduce the total cost of intensive care have met with limited success, partly because of the challenges of calculating how much a day in the ICU actually costs. We discuss these challenges and introduce the concept of total cost savings as an outcome of critical care trials, assuming statistically negative effects on mortality and quality of life.

Does this patient have an exudative pleural effusion? The Rational Clinical Examination systematic review

IMPORTANCE

Thoracentesis is performed to identify the cause of a pleural effusion. Although generally safe, thoracentesis may be complicated by transient hypoxemia, bleeding, patient discomfort, reexpansion pulmonary edema, and pneumothorax.

OBJECTIVE

To identify the best means for differentiating between transudative and exudative effusions and also to identify thoracentesis techniques for minimizing the risk of complications by performing a systematic review the evidence.

DATA SOURCES

We searched The Cochrane Library, MEDLINE, and Embase from inception to February 2014 to identify relevant studies.

STUDY SELECTION

We included randomized and observational studies of adult patients undergoing thoracentesis that examined diagnostic tests for differentiating exudates from transudates and evaluated thoracentesis techniques associated with a successful procedure with minimal complications.

DATA EXTRACTION AND SYNTHESIS

Two investigators independently appraised study quality and extracted data from studies of laboratory diagnosis of pleural effusion for calculation of likelihood ratios (LRs; n = 48 studies) and factors affecting adverse event rates (n = 37 studies).

RESULTS

The diagnosis of an exudate was most accurate if cholesterol in the pleural fluid was greater than 55 mg/dL (LR range, 7.1-250), lactate dehydrogenase (LDH) was greater than 200 U/L (LR, 18; 95% CI, 6.8-46), or the ratio of pleural fluid cholesterol to serum cholesterol was greater than 0.3 (LR, 14; 95% CI, 5.5-38). A diagnosis of exudate was less likely when all Light's criteria (a ratio of pleural fluid protein to serum protein >0.5, a ratio of pleural fluid LDH to serum LDH >0.6, or pleural fluid LDH >two-thirds the upper limit of normal for serum LDH) were absent (LR, 0.04; 95% CI, 0.02-0.11). The most common complication of thoracentesis was pneumothorax, which occurred in 6.0% of cases (95% CI, 4.0%-7.0%). Chest tube placement was required in 2.0% of procedures (95% CI, 0.99%-2.9%) in which a patient was determined to have radiographic evidence of a pneumothorax. With ultrasound, a radiologist's marking the needle insertion site was not associated with decreased pneumothorax events (skin marking vs no skin marking odds ratio [OR], 0.37; 95% CI, 0.08-1.7). Use of ultrasound by any experienced practitioner also was not associated with decreased pneumothorax events (OR, 0.55; 95% CI, 0.06-5.3).

CONCLUSIONS AND RELEVANCE

Light's criteria, cholesterol and pleural fluid LDH levels, and the pleural fluid cholesterol-to-serum ratio are the most accurate diagnostic indicators for pleural exudates. Ultrasound skin marking by a radiologist or ultrasound-guided thoracentesis were not associated with a decrease in pneumothorax events.

The effect of telemedicine in critically ill patients: systematic review and meta-analysis

INTRODUCTION

Telemedicine extends intensivists' reach to critically ill patients cared for by other physicians. Our objective was to evaluate the impact of telemedicine on patients' outcomes.

METHODS

We searched electronic databases through April 2012, bibliographies of included trials, and indexes and conference proceedings in two journals (2001 to 2012). We selected controlled trials or observational studies of critically ill adults or children, examining the effects of telemedicine on mortality. Two authors independently selected studies and extracted data on outcomes (mortality and length of stay in the intensive care unit (ICU) and hospital) and methodologic quality. We used random-effects meta-analytic models unadjusted for case mix or cluster effects and quantified between-study heterogeneity by using I² (the percentage of total variability across studies attributable to heterogeneity rather than to chance).

RESULTS

Of 865 citations, 11 observational studies met selection criteria. Overall quality was moderate (mean score on Newcastle-Ottawa scale, 5.1/9; range, 3 to 9). Meta-analyses showed that telemedicine, compared with standard care, is associated with lower ICU mortality (risk ratio (RR) 0.79; 95% confidence interval (CI), 0.65 to 0.96; nine studies, n = 23,526; I2 = 70%) and hospital mortality (RR, 0.83; 95% CI, 0.73 to 0.94; nine studies, n = 47,943; I² = 72%). Interventions with continuous patient-data monitoring, with or without alerts, reduced ICU mortality (RR, 0.78; 95% CI, 0.64 to 0.95; six studies, n = 21,384; I² = 74%) versus those with remote intensivist consultation only (RR, 0.64; 95% CI, 0.20 to 2.07; three studies, n = 2,142; I2 = 71%), but effects were statistically similar (interaction P = 0.74). Effects were also similar in higher (RR, 0.83; 95% CI, 0.68 to 1.02) versus lower (RR, 0.69; 95% CI, 0.40 to 1.19; interaction, P = 0.53) quality studies. Reductions in ICU and hospital length of stay were statistically significant (weighted mean difference (telemedicine-control), -0.62 days; 95% CI, -1.21 to -0.04 days and -1.26 days; 95% CI, -2.49 to -0.03 days, respectively; I2 > 90% for both).

CONCLUSIONS

Telemedicine was associated with lower ICU and hospital mortality among critically ill patients, although effects varied among studies and may be overestimated in nonrandomized designs. The optimal telemedicine technology configuration and dose tailored to ICU organization and case mix remain unclear.

Trends in Canadian hospital standardised mortality ratios and palliative care coding 2004-2010: a retrospective database analysis

BACKGROUND

The hospital standardised mortality ratio (HSMR), anchored at an average score of 100, is a controversial macromeasure of hospital quality. The measure may be dependent on differences in patient coding, particularly since cases labelled as palliative are typically excluded.

OBJECTIVE

To determine whether palliative coding in Canada has changed since the 2007 national introduction of publicly released HSMRs, and how such changes may have affected results.

DESIGN

Retrospective database analysis.

SETTING

Inpatients in Canadian hospitals from April 2004 to March 2010.

PATIENTS

12 593 329 hospital discharges recorded in the Canadian Institute for Health Information (CIHI) Discharge Abstract Database from April 2004 to March 2010.

MEASUREMENTS

Crude mortality and palliative care coding rates. HSMRs calculated with the same methodology as CIHI. A derived hospital standardised palliative ratio (HSPR) adjusted to a baseline average of 100 in 2004-2005. Recalculated HSMRs that included palliative cases under varying scenarios.

RESULTS

Crude mortality and palliative care coding rates have been increasing over time (p<0.001), in keeping with the nation's advancing overall morbidity. HSMRs in 2008-2010 were significantly lower than in 2004-2006 by 8.55 points (p<0.001). The corresponding HSPR rises dramatically between these two time periods by 48.83 points (p<0.001). Under various HSMR scenarios that included palliative cases, the HSMR would have at most decreased by 6.35 points, and may have even increased slightly.

LIMITATIONS

Inability to calculate a definitively comparable HSMR that include palliative cases and to account for closely timed changes in national palliative care coding guidelines.

CONCLUSIONS

Palliative coding rates in Canadian hospitals have increased dramatically since the public release of HSMR results. This change may have partially contributed to the observed national decline in HSMR.

Lung function and quality of life in survivors of the acute respiratory distress syndrome (ARDS)

Recent studies have begun to describe the long-term outcomes of acute respiratory distress syndrome (ARDS) survivors. These patients experience a number of physical, mental and psychological morbidities that significantly impair their health-related quality of life (HRQL). The trajectory of pulmonary recovery in survivors of ARDS, as it relates to lung function, structure and health-related quality of life (HRQL), is predictable and often persists years after hospital discharge. True pulmonary parenchymal morbidity is uncommon and when present, persistent restrictive disease is likely related to diaphragmatic weakness with a mild reduction in diffusion capacity (DLCO). Future research should focus on identifying patients at risk for long-term functional limitations and the design of rehabilitation interventions tailored to individual patient needs.

Long-term outcomes in patients surviving acute respiratory distress syndrome

Recent studies have begun to describe the long-term outcomes of acute respiratory distress syndrome (ARDS) survivors. These patients experience several physical, mental, and psychological morbidities that significantly impair their health-related quality of life (HRQL). Persistent for years after hospital discharge, decrements in functional and neuropsychological outcomes result in lost savings, employment reduction, and a reduction in HRQL among survivors and their caregivers. Future research should focus on the early identification of patients and their family members at risk for long-term sequelae, the mechanisms of injury leading to long-term ARDS consequences, and therapeutic modalities designed to prevent or decrease these morbidities. Clinicians, caregivers, and patients should be made aware of the deleterious long-term effects of the intensive care unit stay because they are currently poorly recognized and potentially modifiable.

Recruitment maneuvers for acute lung injury: a systematic review

RATIONALE

There are conflicting data regarding the safety and efficacy of recruitment maneuvers (RMs) in patients with acute lung injury (ALI).

OBJECTIVES

To summarize the physiologic effects and adverse events in adult patients with ALI receiving RMs.

METHODS

Systematic review of case series, observational studies, and randomized clinical trials with pooling of study-level data.

MEASUREMENTS AND MAIN RESULTS

Forty studies (1,185 patients) met inclusion criteria. Oxygenation (31 studies; 636 patients) was significantly increased after an RM (PaO2): 106 versus 193 mm Hg, P = 0.001; and PaO2/FiO2 ratio: 139 versus 251 mm Hg, P < 0.001). There were no persistent, clinically significant changes in hemodynamic parameters after an RM. Ventilatory parameters (32 studies; 548 patients) were not significantly altered by an RM, except for higher PEEP post-RM (11 versus 16 cm H2O; P = 0.02). Hypotension (12%) and desaturation (9%) were the most common adverse events (31 studies; 985 patients). Serious adverse events (e.g., barotrauma [1%] and arrhythmias [1%]) were infrequent. Only 10 (1%) patients had their RMs terminated prematurely due to adverse events.

CONCLUSIONS

Adult patients with ALI receiving RMs experienced a significant increase in oxygenation, with few serious adverse events. Transient hypotension and desaturation during RMs is common but is self-limited without serious short-term sequelae. Given the uncertain benefit of transient oxygenation improvements in patients with ALI and the lack of information on their influence on clinical outcomes, the routine use of RMs cannot be recommended or discouraged at this time. RMs should be considered for use on an individualized basis in patients with ALI who have life-threatening hypoxemia.

Efficacy and safety evaluation of human reovirus type 3 in immunocompetent animals: racine and nonhuman primates

PURPOSE

Human reovirus type 3 has been proposed to kill cancer cells with an activated Ras signaling pathway. The purpose of this study was to investigate the efficacy of reovirus in immunocompetent glioma animal models and safety/toxicity in immunocompetent animals, including nonhuman primates.

EXPERIMENTAL DESIGN

Racine glioma cells 9L and RG2 were implanted s.c. or intracranially in Fisher 344 rats with or without reovirus antibodies, followed by treatment of reovirus. To study whether reovirus kills contralateral tumors in the brain and to determine viral distribution, we established an in situ dual tumor model followed by reovirus intratumoral inoculation only into the ipsilateral tumor. To evaluate neurotoxicity/safety of reovirus, Cynomolgus monkeys and immunocompetent rats were given intracranially with reovirus, and pathological examination and/or behavioral studies were done. Viral shedding and clinical biochemistry were systematically studied in monkeys.

RESULTS

Intratumorally given reovirus significantly suppressed the growth of both s.c. and intracranially tumors and significantly prolonged survival. The presence of reovirus-neutralizing antibodies did not abort the reovirus' antitumor effect. Reovirus inhibited glioma growth intracranially in the ipsilateral but not the contralateral tumors; viral load in ipsilateral tumors was 15 to 330-fold higher than the contralateral tumors. No encephalitis or behavioral abnormalities were found in monkeys and rats given reovirus intracranially. No treatment-related clinical biochemistry changes or diffuse histopathological abnormality were found in monkeys inoculated intracranially with Good Manufacturing Practice prepared reovirus. Microscopic changes were confined to the region of viral inoculation and were dose related, suggesting reovirus intracranially was well tolerated in nonhuman primates.

CONCLUSIONS

These data show the efficacy and safety of reovirus when it is used in the treatment of gliomas in immunocompetent hosts. Inoculation of reovirus into the brain of nonhuman primates did not produce significant toxicities.

Reovirus as an oncolytic agent against experimental human malignant gliomas

BACKGROUND

Reovirus is a naturally occurring oncolytic virus that usurps activated Ras-signaling pathways of tumor cells for its replication. Ras pathways are activated in most malignant gliomas via upstream signaling by receptor tyrosine kinases. The purpose of this study was to determine the effectiveness of reovirus as an experimental treatment for malignant gliomas.

METHODS

We investigated whether reovirus would infect and lyse human glioma cell lines in vitro. We also tested the effect of injecting live reovirus in vivo on human gliomas grown subcutaneously or orthotopically (i.e., intracerebrally) in mice. Finally, reovirus was tested ex vivo against low-passage cell lines derived from human glioma specimens. All P values were two-sided.

RESULTS

Reovirus killed 20 (83%) of 24 established malignant glioma cell lines tested. It caused a dramatic and often complete tumor regression in vivo in two subcutaneous (P =.0002 for both U251N and U87) and in two intracerebral (P =.0004 for U251N and P =.0009 for U87) human malignant glioma mouse models. As expected, serious toxic effects were found in these severely immunocompromised hosts. In a less immunocompromised mouse model, a single intratumoral inoculation of live reovirus led to a dramatic prolongation of survival (compared with control mice treated with dead virus; log-rank test, P<.0001 for both U251N and U87 cell lines). The animals treated with live virus also appeared to be healthier and gained body weight (P =.0001). We then tested the ability of reovirus to infect and kill primary cultures of brain tumors removed from patients and found that it killed nine (100%) of nine glioma specimens but none of the cultured meningiomas.

CONCLUSIONS

Reovirus has potent activity against human malignant gliomas in vitro, in vivo, and ex vivo. Oncolysis with reovirus may be a potentially useful treatment for a broad range of human cancers.

Marked inhibition of tumor growth in a malignant glioma tumor model by a novel synthetic matrix metalloproteinase inhibitor AG3340

Synthetic matrix metalloproteinase (MMP) inhibitors have activity against a variety of tumors in preclinical models but have not been studied in gliomas. We determined the effect of AG3340, a novel synthetic MMP inhibitor with Ki values against gelatinases in the low picomolar range, on the growth of a human malignant glioma cell line (U87) in SCID-NOD mice. Mice were injected s.c. with U87 cells. Tumors were allowed to grow to a size of approximately 0.5 x 0.5 cm (after about 3 weeks), and the mice were randomized to receive either: (a) 100 mg/kg AG3340 in vehicle; or (b) vehicle control (0.5% carboxymethyl cellulose, 0.1% pluronic F68), both given daily i.p. Tumor area was measured twice weekly, and animals were sacrificed when moribund, or earlier if premorbid histology was examined. In vivo inhibition of tumor growth was profound, with AG3340 decreasing tumor size by 78% compared with controls after 31 days (when controls were sacrificed; P < 0.01, Wilcoxon test). Control animals survived 31 days after the i.p. injections began, and AG3340 mice survived 71 days, representing a >2-fold increase in survival associated with tumor growth delay. Histological examination found that AG3340-treated tumors were smaller, had lower rates of proliferation, and significantly less invasion than control-treated tumors. Hepatic or pulmonary metastases were not seen in either group. In a separate experiment, the tumors were smaller and sampled after a shorter duration of treatment; the changes in proliferation were more marked and occurred earlier than differences in tumor invasion between the two groups. Furthermore, in vitro cell growth was not inhibited at AG3340 concentrations of <1 mM. AG3340 plasma concentrations in vivo, 1 h after administration, ranged from 67 to 365 nM. Thus, AG3340 produced a profound inhibition of glioma tumor growth and invasion. AG3340 markedly increased survival in this in vivo glioma model. Treatment with AG3340 may be potentially useful in patients with malignant gliomas.