Secondary pneumomediastinum in COVID-19 patient: A case managed with VV-ECMO.

Air leak syndrome, including pneumomediastinum (PM), pneumopericardium, pneumothorax, or subcutaneous emphysema, is primarily caused by chest trauma, cardiothoracic surgery, esophageal perforation, and mechanical ventilation. Secondary pneumomediastinum (SP) is a rare complication, with a much lower incidence reported in patients with coronavirus disease 2019 (COVID-19). Our patient was a 44-year-old nonsmoker male with a previous history of obesity (Body Mass Index [BMI] 35 kg/m2), hyperthyroidism, hypokinetic cardiopathy and atrial fibrillation in treatment with flecainide, who presented to the emergency department with 6 days of fever, cough, dyspnea, and respiratory distress. The COVID-19 diagnosis was confirmed based on a polymerase chain reaction (PCR) test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). After initiation of mechanical ventilation, a chest computed tomography (CT) on the first day revealed bilateral multifocal ground-glass opacities, consolidation and an extensive SP and pneumoperitoneum. Our therapeutic strategy was initiation of veno-venous extracorporeal membrane oxygenation (VV-ECMO) as a bridge to recovery after positioning 2 drains (mediastinal and pleural), for both oxygenation and carbon dioxide clearance, to allow protective and ultra-protective ventilation to limit ventilator-induced lung injury (VILI) and the intensity of mechanical power for lung recovery. After another chest CT scan which showed a clear reduction of the PM, 2 pronation and neuromuscular relaxation cycles were also required, with improvement of gas exchange and respiratory mechanics. On the 15th day, lung function recovered and the patient was then weaned from VV-ECMO, and ultimately made a good recovery and was discharged. In conclusion, SP may be a reflection of extensive alveolar damage and should be considered as a potential predictive factor for adverse outcome in critically ill SARS-CoV2 patients.

Incidence of Acute Kidney Injury in Polytrauma Patients and Predictive Performance of TIMP2 × IGFBP7 Biomarkers for Early Identification of Acute Kidney Injury.

Background: Acute kidney injury (AKI) is a common cause of organ failure in trauma patients who survive their initial injuries. It is independently associated with increased morbidity and mortality and prolongs the length of hospital stays. The objectives of this study were to describe the incidence of early AKI and influence of risk factors in polytrauma patients and evaluate the predictive potential of TIMP2 × IGFBP7 biomarkers in this patient cohort. Methods: We conducted a retrospective cohort study of severely injured adult patients who were consecutively admitted to a multidisciplinary ICU from May 2017 to May 2019. Detailed patient data was retrieved from ICU medical records. Fluid balance, urinary output, and sCr values up to 72 h were collected. Urine samples for measuring TIMP2 × IGFBP7 concentrations were obtained and analyzed from ICU admission to 72 h. Results: Among the 153 patients eligible for analysis, 45 were included in the AKI, and 108 in the no AKI cohorts. The incidence of AKI within 72 h, based on KDIGO criteria, was 28.8%. There were no differences in ISS, type and mechanism of injury, heart rate, and systolic BP at admission between groups. Patients with early AKI were older (68 vs. 49 years, p < 0.001), obese (BMI 26.2 vs. 24.7, p < 0.048), and more likely to have previous cardiac disease (27% vs. 5.6%, p < 0.001). TIMP2 × IGFBP7 values on ICU admission were associated with subsequent AKI in patients without evidence of AKI at the time of ICU admission. They were also higher in the AKI cohort and significantly correlated with renal replacement therapy (RRT) and episodes of hypotension. Multivariable analysis confirmed age, previous cardiac disease, and NephroCheck as the variables mostly associated with AKI, with AUC 0.792. Conclusions: TIMP2 × IGFBP7 may help identify trauma patients with tubular damage that may evolve into a clinically manifested syndrome. Prospective studies of TIMP2 × IGFBP7, as a trigger for early AKI bundle care, are warranted.

Flow Dynamic Analysis by Contrast-Enhanced Imaging Techniques of Medium Cutoff Membrane Hemodialyzer.

INTRODUCTION: Medium cutoff (MCO) membranes represent an interesting innovation in the field of hemodialysis. Given the correlation between large (PM >25 kDa) middle molecules (LMM) and clinical outcomes, the possibility to broaden the spectrum of solutes removed in hemodialysis with MCO membranes introduces a new perspective for end-stage kidney disease patients. Due to low diffusion coefficients of LMM, the use of convection is required to maximize extracorporeal clearance. High convective rates are achieved with high-flux membranes in hemodiafiltration, a technique not available in the US. In case of the MCO membrane, remarkable clearances of LMM are achieved combining the permeability of the membrane with a significant amount of internal convection. The mechanism of filtration-backfiltration inside the dialyzer enables effective removal of LMM in a technique called expanded hemodialysis (HDx). Given such theoretical explanation, it is important to demonstrate the blood and ultrafiltration rheology inside the MCO dialyzer. METHOD: This study for the first time describes flow dynamic parameters and internal cross-filtration, thanks to specific radiology and nuclear imaging techniques. RESULTS: Flow dynamic analysis of the blood and dialysate compartment confirms excellent distribution of velocities and an excellent matching of blood and dialysate. Average blood flow velocity allows for wall shear rates adequate to avoid protein stagnation at the blood membrane interface and increase in blood viscosity. Cross-filtration analysis demonstrates a remarkable filtration/backfiltration flux reaching values >30 mL/min at a blood flow of 300 mL/min and zero net filtration. CONCLUSION: The MCO dialyzer Theranova 400 appears to have a design optimized to perform expanded hemodialysis (HDx).

Vancomycin Adsorption During in vitro Model of Hemoperfusion with HA380 Cartridge.

INTRODUCTION: A critical point for using blood purification during sepsis may be the potential interaction with antimicrobial therapy, the mainstay of sepsis treatment. The aim of our study was to investigate the vancomycin removal during hemoperfusion (HP) using HA380 cartridge. METHODS: This is an experimental study, in which 500 mL of solution was circulated in a closed-circuit (blood flow of 250 mL/min) simulating HP ran using HA380. Vancomycin was added to reach a through concentration or a very high concentration to evaluate the removal ratio (RR) during 120 min of HP. Comparison between blood-crystalloid solution and balanced solution was performed by using Kruskal-Wallis test. The kinetics of vancomycin removal and the adsorption isotherm were evaluated. RESULTS: We found a complete removal of vancomycin at baseline through concentration of 23.0 ± 7.4 mg/L. Using extremely high concentration (baseline 777.0 ± 62.2 mg/L), RR was 90.1 ± 0.6% at 5 min and 99.2 ± 0.6% at 120 min. No difference in terms of RR was found between blood-crystalloid mixture and balanced solution. The kinetics of the vancomycin reduction followed an exponential decay. Repeated boluses (total amount of 2,000 mg) resulted in cumulative adsorption of 1,919.4 mg with RR of 96.6 ± 1.4%, regardless of the amount injected (100 vs. 500 mg). Vancomycin adsorption onto HA380 followed the Langmuir isotherm model. CONCLUSIONS: A considerable amount of vancomycin was rapidly removed during in vitro HP with HA380. Clinical studies are needed to determine whether this may lead to underdosing. Drug therapeutic monitoring is highly recommended when using HA380 for blood purification in patients receiving vancomycin.

Extracorporeal carbon dioxide removal in heart-beating donor with acute severe asthma: A case report.

Status asthmaticus is a life-threatening disorder that can manifest in dangerous levels of hypercapnia and acidosis. The use of extracorporeal carbon dioxide removal (ECCO2R) has been used successfully to control pH and PaCO2 in patients with acute severe asthma. The present report describes the use of this technology in near-fatal asthma with brain death, and awaiting organ harvest. The ProLUNG® system consists of a veno-venous hemoperfusion circuit with an artificial lung polymethylpentene membrane coated with phosphorylcholine with a surface of 1.81 m2. The system can reach a blood flow of 450 ml/min trough a double-lumen central venous catheter (13.0 Fr) placed in femoral, subclavian or jugular vein. The platform is provided with automated management of airflow and VCO2 monitoring during treatment. The patient was maintained on extracorporeal treatment ensuring stable arterial pH control and PaCO2 control. In acute status asthmaticus, complicated with cardiac arrest, mini-invasive ECCO2R was an effective method of controlling pH and PaCO2, for optimizing hemodynamic and aerobic metabolism and for performing protective ventilation for an optimal organ donor preservation until the organ harvest occurs.