Objectives

Soluble suppression of tumorigenicity-2 is a biomarker of myocardial strain and inflammation. The characteristics of acute respiratory distress syndrome include inflammation and cardiovascular dysfunction. We sought to determine whether plasma soluble suppression of tumorigenicity-2 concentration is associated with outcome and response to conservative fluid management and whether soluble suppression of tumorigenicity-2 concentration discriminates acute respiratory distress syndrome from decompensated heart failure.

Design

A retrospective analysis of the Fluid and Catheter Treatment Trial, a multi-center randomized controlled trial of conservative fluid management in the acute respiratory distress syndrome, as well as of a cohort of patients with decompensated heart failure.

Setting

Twenty acute care hospitals.

Patients

Eight hundred twenty-six patients with acute respiratory distress syndrome and 209 patients with acutely decompensated heart failure.

Measurements and main results

Nonsurvivors had higher day 0 (p < 0.0001) and day 3 (p < 0.0001) soluble suppression of tumorigenicity-2 concentrations. After adjustment for severity of illness, higher soluble suppression of tumorigenicity-2 concentration was associated with mortality, with odds ratioadj 1.47 (95% CI, 0.99-2.20; p = 0.06) at day 0, 2.94 (95% CI, 2.00-4.33; p < 0.0001) at day 3, and 3.63 (95% CI, 2.38-5.53; p < 0.0001) if soluble suppression of tumorigenicity-2 increased between days. Cumulative fluid balance was more positive among patients with higher day 0 (median, 5,212 mL [interquartile range, 200-12,284 mL] vs median, 2,020 mL [interquartile range, -2,034 to 7,091 mL]; p < 0.0001) and day 3 soluble suppression of tumorigenicity-2 (median, 7,678 mL [interquartile range, 2,217-14,278 mL] vs median, 1,492 mL [interquartile range, -2,384 to 6,239 mL]; p < 0.0001). Soluble suppression of tumorigenicity-2 showed excellent discriminative ability between the Fluid and Catheter Treatment Trial and heart failure populations (area under receiver-operating characteristic curve = 0.98; p < 0.0001).

Conclusions

Higher soluble suppression of tumorigenicity-2 concentrations are associated with worse outcome in acute respiratory distress syndrome and may have value for discriminating acute respiratory distress syndrome from heart failure.

Objectives

Soluble suppression of tumorigenicity-2 and interleukin-6 concentrations have been associated with the inflammatory cascade of acute respiratory distress syndrome. We determined whether soluble suppression of tumorigenicity-2 and interleukin-6 levels can be used as prognostic biomarkers to guide weaning from mechanical ventilation and predict the need for reintubation.

Design, setting, and patients

We assayed plasma soluble suppression of tumorigenicity-2 (n = 826) concentrations and interleukin-6 (n = 755) concentrations in the Fluid and Catheter Treatment Trial, a multicenter randomized controlled trial of conservative fluid management in acute respiratory distress syndrome. We tested whether soluble suppression of tumorigenicity-2 and interleukin-6 levels were associated with duration of mechanical ventilation, the probability of passing a weaning assessment, and the need for reintubation.

Measurements and main results

In models adjusted for Acute Physiology and Chronic Health Evaluation score and other relevant variables, patients with higher day 0 and day 3 median soluble suppression of tumorigenicity-2 and interleukin-6 concentrations had decreased probability of extubation over time (day 0 soluble suppression of tumorigenicity-2: hazard ratio, 0.85; 95% CI, 0.72-1.00; p = 0.05; day 0 interleukin-6: hazard ratio, 0.64; 95% CI, 0.54-0.75; p < 0.0001; day 3 soluble suppression of tumorigenicity-2: hazard ratio, 0.64; 95% CI, 0.54-0.75; p < 0.0001; and day 3 interleukin-6: hazard ratio, 0.73; 95% CI, 0.62-0.85; p = 0.0001). Higher biomarker concentrations were also predictive of decreased odds of passing day 3 weaning assessments (soluble suppression of tumorigenicity-2: odds ratio, 0.62: 95% CI, 0.44-0.87; p = 0.006 and interleukin-6: odds ratio, 0.61; 95% CI, 0.43-0.85; p = 0.004) and decreased odds of passing a spontaneous breathing trial (soluble suppression of tumorigenicity-2: odds ratio, 0.45; 95% CI, 0.28-0.71; p = 0.0007 and interleukin-6 univariate analysis only: odds ratio, 0.55; 95% CI, 0.36-0.83; p = 0.005). Finally, higher biomarker levels were significant predictors of the need for reintubation for soluble suppression of tumorigenicity-2 (odds ratio, 3.23; 95% CI, 1.04-10.07; p = 0.04) and for interleukin-6 (odds ratio, 2.58; 95% CI, 1.14-5.84; p = 0.02).

Conclusions

Higher soluble suppression of tumorigenicity-2 and interleukin-6 concentrations are each associated with worse outcomes during weaning of mechanical ventilation and increased need for reintubation in patients with acute respiratory distress syndrome. Biomarker-directed ventilator management may lead to improved outcomes in weaning of mechanical ventilation in patients with acute respiratory distress syndrome.

Background

Treatment with bone-marrow-derived mesenchymal stromal cells (MSCs) has shown benefits in preclinical models of acute respiratory distress syndrome (ARDS). Safety has not been established for administration of MSCs in critically ill patients with ARDS. We did a phase 2a trial to assess safety after administration of MSCs to patients with moderate to severe ARDS.

Methods

We did a prospective, double-blind, multicentre, randomised trial to assess treatment with one intravenous dose of MSCs compared with placebo. We recruited ventilated patients with moderate to severe ARDS (ratio of partial pressure of oxygen to fractional inspired oxygen <27 kPa and positive end-expiratory pressure [PEEP] ≥8 cm H₂O) in five university medical centres in the USA. Patients were randomly assigned 2:1 to receive either 10 × 10⁶/kg predicted bodyweight MSCs or placebo, according to a computer-generated schedule with a variable block design and stratified by site. We excluded patients younger than 18 years, those with trauma or moderate to severe liver disease, and those who had received cancer treatment in the previous 2 years. The primary endpoint was safety and all analyses were done by intention to treat. We also measured biomarkers in plasma. MSC viability was tested in a post-hoc analysis. This trial is registered with ClinicalTrials.gov, number NCT02097641.

Findings

From March 24, 2014, to Feb 9, 2017 we screened 1038 patients, of whom 60 were eligible for and received treatment. No patient experienced any of the predefined MSC-related haemodynamic or respiratory adverse events. One patient in the MSC group died within 24 h of MSC infusion, but death was judged to be probably unrelated. 28-day mortality did not differ between the groups (30% in the MSC group vs 15% in the placebo group, odds ratio 2·4, 95% CI 0·5-15·1). At baseline, the MSC group had numerically higher mean scores than the placebo group for Acute Physiology and Chronic Health Evaluation III (APACHE III; 104 [SD 31] vs 89 [33]), minute ventilation (11·1 [3·2] vs 9·6 [2·4] L/min), and PEEP (12·4 [3·7] vs 10·8 [2·6] cm H₂O). After adjustment for APACHE III score, the hazard ratio for mortality at 28 days was 1·43 (95% CI 0·40-5·12, p=0·58). Viability of MSCs ranged from 36% to 85%.

Interpretation

One dose of intravenous MSCs was safe in patients with moderate to severe ARDS. Larger trials are needed to assess efficacy, and the viability of MSCs must be improved.

Funding

National Heart, Lung, and Blood Institute.

Background

No effective pharmacotherapy for acute respiratory distress syndrome (ARDS) exists, and mortality remains high. Preclinical studies support the efficacy of mesenchymal stem (stromal) cells (MSCs) in the treatment of lung injury. We aimed to test the safety of a single dose of allogeneic bone marrow-derived MSCs in patients with moderate-to-severe ARDS.

Methods

The STem cells for ARDS Treatment (START) trial was a multicentre, open-label, dose-escalation, phase 1 clinical trial. Patients were enrolled in the intensive care units at University of California, San Francisco, CA, USA, Stanford University, Stanford, CA, USA, and Massachusetts General Hospital, Boston, MA, USA, between July 8, 2013, and Jan 13, 2014. Patients were included if they had moderate-to-severe ARDS as defined by the acute onset of the need for positive pressure ventilation by an endotracheal or tracheal tube, a PaO2:FiO2 less than 200 mm Hg with at least 8 cm H2O positive end-expiratory airway pressure (PEEP), and bilateral infiltrates consistent with pulmonary oedema on frontal chest radiograph. The first three patients were treated with low dose MSCs (1 million cells/kg predicted bodyweight [PBW]), the next three patients received intermediate dose MSCs (5 million cells/kg PBW), and the final three patients received high dose MSCs (10 million cells/kg PBW). Primary outcomes included the incidence of prespecified infusion-associated events and serious adverse events. The trial is registered with ClinicalTrials.gov, number NCT01775774.

Findings

No prespecified infusion-associated events or treatment-related adverse events were reported in any of the nine patients. Serious adverse events were subsequently noted in three patients during the weeks after the infusion: one patient died on study day 9, one patient died on study day 31, and one patient was discovered to have multiple embolic infarcts of the spleen, kidneys, and brain that were age-indeterminate, but thought to have occurred before the MSC infusion based on MRI results. None of these severe adverse events were thought to be MSC-related.

Interpretation

A single intravenous infusion of allogeneic, bone marrow-derived human MSCs was well tolerated in nine patients with moderate to severe ARDS. Based on this phase 1 experience, we have proceeded to phase 2 testing of MSCs for moderate to severe ARDS with a primary focus on safety and secondary outcomes including respiratory, systemic, and biological endpoints.

Funding

The National Heart, Lung, and Blood Institute.

Introduction

About one-third of critically ill patients with acute kidney injury (AKI) develop persistently decreased kidney function, known as acute kidney disease (AKD), which may progress to chronic kidney disease (CKD). Although sepsis is the most common cause of AKI, little is known about sepsis-associated AKD.

Methods

Using data from a large randomized trial including 1341 patients with septic shock, we studied patients with stage 2 or 3 AKI on day 1 of hospitalization. We defined AKD as a persistently reduced glomerular filtration rate for >7 days. In addition to clinical data, we measured several urinary biomarkers (tissue inhibitor of metalloproteinases-2 and insulin-like growth factor-binding protein 7 [TIMP-2∗IGFBP7], neutrophil gelatinase-associated lipocalin [NGAL], kidney injury molecule-1 [KIM-1], liver-type fatty acid binding protein, and type 4 collagen) at 0, 6, and 24 hours, to predict AKD.

Results

Of 598 patients, 119 (19.9%) died within 7 days, 318 (53.2%) had early reversal of AKI within the first 7 days, whereas 161 (26.9%) developed AKD. In patients with early reversal, 45 (14.2%) had relapsed AKI after early reversal, and only about one-third of these recovered. Among patients developing AKD, only 15 (9.3%) recovered renal function prior to discharge. Male sex, African American race, and underlying CKD were more predominant in patients developing AKD. None of the biomarkers tested performed well for prediction of AKD, although NGAL modestly increased the performance of a clinical model.

Conclusions

AKD is common in patients with septic shock, especially among African American males and those with underlying CKD. Existing AKI biomarkers have limited utility for predicting AKD but might be useful together with clinical variables. Novel predictive biomarkers for renal recovery are needed.