The unrestricted global effort to complete the COOL trial

BACKGROUND

Severe complicated intra-abdominal sepsis (SCIAS) has an increasing incidence with mortality rates over 80% in some settings. Mortality typically results from disruption of the gastrointestinal tract, progressive and self-perpetuating bio-mediator generation, systemic inflammation, and multiple organ failure. A further therapeutic option may be open abdomen (OA) management with negative peritoneal pressure therapy (NPPT) to remove inflammatory ascites and attenuate the systemic damage from SCIAS, although there are definite risks of leaving the abdomen open whenever it might possibly be closed. This potential therapeutic paradigm is the rationale being assessed in the Closed Or Open after Laparotomy (COOL trial) ( https://clinicaltrials.gov/ct2/show/NCT03163095 ). Initially, the COOL trial received Industry sponsorship; however, this funding mandated the use of a specific trademarked and expensive NPPT device in half of the patients allocated to the intervention (open) arm. In August 2022, the 3 M/Acelity Corporation without consultation but within the terms of the contract canceled the financial support of the trial. Although creating financial difficulty, there is now no restriction on specific NPPT devices and removing a cost-prohibitive intervention creates an opportunity to expand the COOL trial to a truly global basis. This document describes the evolution of the COOL trial, with a focus on future opportunities for global growth of the study.

METHODS

The COOL trial is the largest prospective randomized controlled trial examining the random allocation of SCIAS patients intra-operatively to either formal closure of the fascia or the use of the OA with an application of an NPPT dressing. Patients are eligible if they have free uncontained intraperitoneal contamination and physiologic derangements exemplified by septic shock OR severely adverse predicted clinical outcomes. The primary outcome is intended to definitively inform global practice by conclusively evaluating 90-day survival. Initial recruitment has been lower than hoped but satisfactory, and the COOL steering committee and trial investigators intend with increased global support to continue enrollment until recruitment ensures a definitive answer.

DISCUSSION

OA is mandated in many cases of SCIAS such as the risk of abdominal compartment syndrome associated with closure, or a planned second look as for example part of "damage control"; however, improved source control (locally and systemically) is the most uncertain indication for an OA. The COOL trial seeks to expand potential sites and proceed with the evaluation of NPPT agnostic to device, to properly examine the hypothesis that this treatment attenuates systemic damage and improves survival. This approach will not affect internal validity and should improve the external validity of any observed results of the intervention.

TRIAL REGISTRATION

National Institutes of Health ( https://clinicaltrials.gov/ct2/show/NCT03163095 ).

Study of Alteplase for Respiratory Failure in SARS-CoV-2 COVID-19: A Vanguard Multicenter, Rapidly Adaptive, Pragmatic, Randomized Controlled Trial

Background

Pulmonary vascular microthrombi are a proposed mechanism of COVID-19 respiratory failure. We hypothesized that early administration of tissue plasminogen activator (tPA) followed by therapeutic heparin would improve pulmonary function in these patients.

Research Question

Does tPA improve pulmonary function in severe COVID-19 respiratory failure, and is it safe?

Study Design and Methods

Adults with COVID-19-induced respiratory failure were randomized from May14, 2020 through March 3, 2021, in two phases. Phase 1 (n = 36) comprised a control group (standard-of-care treatment) vs a tPA bolus (50-mg tPA IV bolus followed by 7 days of heparin; goal activated partial thromboplastin time [aPTT], 60-80 s) group. Phase 2 (n = 14) comprised a control group vs a tPA drip (50-mg tPA IV bolus, followed by tPA drip 2 mg/h plus heparin 500 units/h over 24 h, then heparin to maintain aPTT of 60-80 s for 7 days) group. Patients were excluded from enrollment if they had not undergone a neurologic examination or cross-sectional brain imaging within the previous 4.5 h to rule out stroke and potential for hemorrhagic conversion. The primary outcome was Pao₂ to Fio₂ ratio improvement from baseline at 48 h after randomization. Secondary outcomes included Pao₂ to Fio₂ ratio improvement of > 50% or Pao₂ to Fio₂ ratio of ≥ 200 at 48 h (composite outcome), ventilator-free days (VFD), and mortality.

Results

Fifty patients were randomized: 17 in the control group and 19 in the tPA bolus group in phase 1 and eight in the control group and six in the tPA drip group in phase 2. No severe bleeding events occurred. In the tPA bolus group, the Pao₂ to Fio₂ ratio values were significantly (P < .017) higher than baseline at 6 through 168 h after randomization; the control group showed no significant improvements. Among patients receiving a tPA bolus, the percent change of Pao₂ to Fio₂ ratio at 48 h (16.9% control [interquartile range (IQR), –8.3% to 36.8%] vs 29.8% tPA bolus [IQR, 4.5%-88.7%]; P = .11), the composite outcome (11.8% vs 47.4%; P = .03), VFD (0.0 [IQR, 0.0-9.0] vs 12.0 [IQR, 0.0-19.0]; P = .11), and in-hospital mortality (41.2% vs 21.1%; P = .19) did not reach statistically significant differences when compared with those of control participants. The patients who received a tPA drip did not experience benefit.

Interpretation

The combination of tPA bolus plus heparin is safe in severe COVID-19 respiratory failure. A phase 3 study is warranted given the improvements in oxygenation and promising observations in VFD and mortality.

Trial Registry

ClinicalTrials.gov; No.: NCT04357730; URL: www.clinicaltrials.gov

Urinary Glycosaminoglycans Predict Outcomes in Septic Shock and Acute Respiratory Distress Syndrome

RATIONALE

Degradation of the endothelial glycocalyx, a glycosaminoglycan (GAG)-rich layer lining the vascular lumen, is associated with the onset of kidney injury in animal models of critical illness. It is unclear if similar pathogenic degradation occurs in critically ill patients.

OBJECTIVES

To determine if urinary indices of GAG fragmentation are associated with outcomes in patients with critical illnesses such as septic shock or acute respiratory distress syndrome (ARDS).

METHODS

We prospectively collected urine from 30 patients within 24 hours of admission to the Denver Health Medical Intensive Care Unit (ICU) for septic shock. As a nonseptic ICU control, we collected urine from 25 surgical ICU patients admitted for trauma. As a medical ICU validation cohort, we obtained serially collected urine samples from 70 patients with ARDS. We performed mass spectrometry on urine samples to determine GAG (heparan sulfate, chondroitin sulfate, and hyaluronic acid) concentrations as well as patterns of heparan sulfate/chondroitin sulfate disaccharide sulfation. We compared these indices to measurements obtained using dimethylmethylene blue, an inexpensive, colorimetric urinary assay of sulfated GAGs.

MEASUREMENTS AND MAIN RESULTS

In septic shock, indices of GAG fragmentation correlated with both the development of renal dysfunction over the 72 hours after urine collection and with hospital mortality. This association remained after controlling for severity of illness and was similarly observed using the inexpensive dimethylmethylene blue assay. These predictive findings were corroborated using urine samples previously collected at three consecutive time points from patients with ARDS.

CONCLUSIONS

Early indices of urinary GAG fragmentation predict acute kidney injury and in-hospital mortality in patients with septic shock or ARDS. Clinical trial registered with www.clinicaltrials.gov (NCT01900275).

Analysis of Total Human Urinary Glycosaminoglycan Disaccharides by Liquid Chromatography-Tandem Mass Spectrometry

The determination of complex analytes, present at low concentrations, in biological fluids poses a difficult challenge. This study relies on an optimized method of recovery, enzymatic treatment, and disaccharide analysis by liquid chromatography-tandem mass spectrometry to rapidly determine low concentrations of glycosaminoglycans in human urine. The approach utilizes multiple reaction monitoring (MRM) of glycosaminoglycan disaccharides obtained from treating urine samples with recombinant heparin lyases and chondroitin lyase. This rapid and sensitive method allows the analysis of glycosaminoglycan content and disaccharide composition in urine samples having concentrations 10- to 100-fold lower than those typically analyzed from patients with metabolic diseases, such as mucopolysaccharidosis. The current method facilitates the analysis low (ng/mL) levels of urinary glycosaminoglycans present in healthy individuals and in patients with pathological conditions, such as inflammation and cancers, that can subtly alter glycosaminoglycan content and composition.

Diagnostic peritoneal lavage: accuracy in predicting necessary laparotomy following blunt and penetrating trauma

The purpose of this study was to evaluate the ability of diagnostic peritoneal lavage (DPL) to predict intra-abdominal injuries that required surgical repair. To do this, we retrospectively reviewed 944 patients with blunt and penetrating abdominal trauma who underwent 975 DPLs. Initial DPL in 608 patients sustaining blunt trauma had a sensitivity of 87%, a specificity of 97%, an accuracy of 95%, a positive predictive value (PPV) of 85%, and a negative predictive value (NPV) of 97%. Initial DPL in 336 patients with penetrating trauma had a sensitivity of 87%, a specificity of 89%, an accuracy of 89%, a PPV of 75%, and a NPV of 95%. When utilizing final lavage results on the 944 patients, DPL had a sensitivity of 91%, a specificity of 94%, an accuracy of 93%, a PPV of 80%, and a NPV of 98% in predicting intra-abdominal injury requiring surgical repair.

A plea for sensible management of myocardial contusion

The purpose of this study was to define the relative risk of life-threatening sequelae in patients at risk for myocardial contusion. During a 3-year period, 280 patients sustaining blunt chest trauma were admitted to the surgical intensive care unit to exclude myocardial contusion. Patients were evaluated by electrocardiogram and creatine phosphokinase (CPK) MB enzyme levels every 8 hours for a minimum of 48 hours. Myocardial contusion was identified in 35 patients (13 percent); the diagnosis was established by transient electrocardiographic changes (30), CPK-MB more than 3 percent (9) or both criteria (4). Two patients (1 percent) died from cardiac decompensation 4 and 12 hours postinjury, and seven (3 percent) required early (12 hours postinjury) intensive care unit treatment of arrhythmias or myocardial failure. None of the remaining 271 patients developed cardiac symptoms. This clinical experience underscores the low incidence of cardiac sequelae among patients at risk for myocardial contusion. Complications were always manifest within 12 hours of injury. The clinical diagnosis of myocardial contusion can be excluded pragmatically in the asymptomatic patient with a normal electrocardiogram and CPK-MB levels during the initial 24-hour postinjury period.

Presumptive antibiotics for penetrating abdominal wounds

The optimal antimicrobial agent or agents for penetrating abdominal injuries remains undetermined. During the three year period ending August 1987, 317 consecutive patients undergoing celiotomy for penetrating abdominal trauma were prospectively randomized to receive either mezlocillin, 4 grams every six hours, or clindamycin, 600 milligrams every six hours, and gentamicin, loading dose of 2.0 milligrams per kilogram, then 1.5 kilograms every eight hours. Antibiotics were begun in the emergency department with duration of coverage based on the pattern of injury: the colon, five days; other hollow visceral injury, two days, and all others, one day. Twenty-three patients were excluded because of breach of protocol and 16 others died within 72 hours of presentation. The two study groups, 136 patients receiving mezlocillin and 142 patients receiving gentamicin and clindamycin, were comparable with respect to age, sex, mechanism of injury, shock, intraoperative replacement of blood, abdominal trauma index and distribution of hollow visceral injuries. The over-all incidence of septic morbidity was similar: infections developed in 21 (15 per cent) of the patients receiving mezlocillin compared with 19 (13 per cent) of patients receiving gentamicin and clindamycin. There was no significant difference in major infections (lobar pneumonia and intra-abdominal abscess), with 13 per cent in each group. The offending pathogens were similar. The most common isolates in intra-abdominal abscess were Escherichia coli, Klebsiella and Enterococcus species and anaerobic Bacteroides species. Mezlocillin, an extended spectrum penicillin, achieved similar results, compared with the expensive and potentially toxic combination regimen in patients with penetrating abdominal injuries.