Patient Recruitment Rate in Multicentered Randomized Trials in Critical Care

Early Serial Echocardiographic and Ultrasonographic Findings in Critically Ill Patients With COVID-19

Background

Cardiac function of critically ill patients with COVID-19 generally has been reported from clinically obtained data. Echocardiographic deformation imaging can identify ventricular dysfunction missed by traditional echocardiographic assessment.

Research Question

What is the prevalence of ventricular dysfunction and what are its implications for the natural history of critical COVID-19?

Study Design and Methods

This is a multicenter prospective cohort of critically ill patients with COVID-19. We performed serial echocardiography and lower extremity vascular ultrasound on hospitalization days 1, 3, and 8. We defined left ventricular (LV) dysfunction as the absolute value of longitudinal strain of < 17% or left ventricle ejection fraction (LVEF) of < 50%. Primary clinical outcome was inpatient survival.

Results

We enrolled 110 patients. Thirty-nine (35.5%) died before hospital discharge. LV dysfunction was present at admission in 38 patients (34.5%) and in 21 patients (36.2%) on day 8 (P = .59). Median baseline LVEF was 62% (interquartile range [IQR], 52%-69%), whereas median absolute value of baseline LV strain was 16% (IQR, 14%-19%). Survivors and nonsurvivors did not differ statistically significantly with respect to day 1 LV strain (17.9% vs 14.4%; P = .12) or day 1 LVEF (60.5% vs 65%; P = .06). Nonsurvivors showed worse day 1 right ventricle (RV) strain than survivors (16.3% vs 21.2%; P = .04).

Interpretation

Among patients with critical COVID-19, LV and RV dysfunction is common, frequently identified only through deformation imaging, and early (day 1) RV dysfunction may be associated with clinical outcome.

High-Dose IV Hydroxocobalamin (Vitamin B12) in Septic Shock: A Double-Blind, Allocation-Concealed, Placebo-Controlled Single-Center Pilot Randomized Controlled Trial (The Intravenous Hydroxocobalamin in Septic Shock Trial)

BACKGROUND

Elevated hydrogen sulfide (H₂S) contributes to vasodilatation and hypotension in septic shock, and traditional therapies do not target this pathophysiologic mechanism. High-dose IV hydroxocobalamin scavenges and prevents H₂S formation, which may restore vascular tone and may accentuate recovery. No experimental human studies have tested high-dose IV hydroxocobalamin in adults with septic shock.

RESEARCH QUESTION

In adults with septic shock, is comparing high-dose IV hydroxocobalamin with placebo feasible?

STUDY DESIGN AND METHODS

We conducted a phase 2 single-center, double-blind, allocation-concealed, placebo-controlled, parallel-group pilot randomized controlled trial comparing high-dose IV hydroxocobalamin with placebo in critically ill adults with septic shock. Patients meeting Sepsis 3 criteria were randomized 1:1 to receive a single 5-g dose of high-dose IV hydroxocobalamin or equivalent volume 0.9% saline solution as placebo. The primary outcome was study feasibility (enrollment rate, clinical and laboratory compliance rate, and contamination rate). Secondary outcomes included between-group differences in plasma H₂S concentrations and vasopressor dose before and after infusion.

RESULTS

Twenty patients were enrolled over 19 months, establishing an enrollment rate of 1.05 patients per month. Protocol adherence rates were 100% with zero contamination. In the high-dose IV hydroxocobalamin group, compared to placebo, there was a greater reduction in vasopressor dose between randomization and postinfusion (-36% vs 4%, P < .001) and randomization and 3-h postinfusion (-28% vs 10%, P = .019). In the high-dose IV hydroxocobalamin group, the plasma H₂S level was reduced over 45 mins by -0.80 ± 1.73 μM, as compared with -0.21 ± 0.64 μM in the placebo group (P = .3).

INTERPRETATION

This pilot trial established favorable feasibility metrics. Consistent with the proposed mechanism of benefit, high-dose IV hydroxocobalamin compared with placebo was associated with reduced vasopressor dose and H₂S levels at all time points and without serious adverse events. These data provide the first proof of concept for feasibility of delivering high-dose IV hydroxocobalamin in septic shock.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT03783091; URL: www.

CLINICALTRIALS

gov.

A systematic review and meta-analysis of enrollment into ARDS and sepsis trials published between 2009 and 2019 in major journals

BACKGROUND

Enrollment problems are common among randomized controlled trials conducted in the ICU. However, little is known about actual trial enrollment rates and influential factors. We set out to determine the overall enrollment rate in recent randomized controlled trials (RCTs) of patients with acute respiratory distress syndrome (ARDS), acute lung injury (ALI), or sepsis, and which factors influenced enrollment rate.

METHODS

We conducted a systematic review by searching Pubmed using predefined terms for ARDS/ALI and sepsis to identify individually RCTs published among the seven highest impact general medicine and seven highest impact critical care journals between 2009 and 2019. Cluster randomized trials were excluded. Data were extracted by two independent reviewers using an electronic database management system. We conducted a random-effects meta-analysis of the eligible trials for the primary outcome of enrollment rate by time and site.

RESULTS

Out of 457 articles identified, 94 trials met inclusion criteria. Trials most commonly evaluated pharmaceutical interventions (53%), were non-industry funded (78%), and required prospective informed consent (81%). The overall mean enrollment rate was 0.83 (95% confidence interval: 0.57-1.21) participants per month per site. Enrollment in ARDS/ALI and sepsis trials were 0.48 (95% CI 0.32-0.70) and 0.98 (95% CI 0.62-1.56) respectively. The enrollment rate was significantly higher for single-center trials (4.86; 95% CI 2.49-9.51) than multicenter trials (0.52; 95% CI 0.41-0.66). Of the 36 trials that enrolled < 95% of the target sample size, 8 (22%) reported slow enrollment as the reason.

CONCLUSIONS

In this systematic review and meta-analysis, recent ARDS/ALI and sepsis clinical trials had an overall enrollment rate of less than 1 participant per site per month. Novel approaches to improve critical care trial enrollment efficiency are needed to facilitate the translation of best evidence into practice.