Quantitative assessment of lung involvement on chest CT at admission: Impact on hypoxia and outcome in COVID-19 patients.

BACKGROUND: The aim of this study was to quantify COVID-19 pneumonia features using CT performed at time of admission to emergency department in order to predict patients' hypoxia during the hospitalization and outcome. METHODS: Consecutive chest CT performed in the emergency department between March 1st and April 7th 2020 for COVID-19 pneumonia were analyzed. The three features of pneumonia (GGO, semi-consolidation and consolidation) and the percentage of well-aerated lung were quantified using a HU threshold based software. ROC curves identified the optimal cut-off values of CT parameters to predict hypoxia worsening and hospital discharge. Multiple Cox proportional hazards regression was used to analyze the capability of CT quantitative features, demographic and clinical variables to predict the time to hospital discharge. RESULTS: Seventy-seven patients (median age 56-years-old, 51 men) with COVID-19 pneumonia at CT were enrolled. The quantitative features of COVID-19 pneumonia were not associated to age, sex and time-from-symptoms onset, whereas higher number of comorbidities was correlated to lower well-aerated parenchyma ratio (rho = -0.234, p = 0.04) and increased semi-consolidation ratio (rho = -0.303, p = 0.008). Well-aerated lung (≤57%), semi-consolidation (≥17%) and consolidation (≥9%) predicted worst hypoxemia during hospitalization, with moderate areas under curves (AUC 0.76, 0.75, 0.77, respectively). Multiple Cox regression identified younger age (p < 0.01), female sex (p < 0.001), longer time-from-symptoms onset (p = 0.049), semi-consolidation ≤17% (p < 0.01) and consolidation ≤13% (p = 0.03) as independent predictors of shorter time to hospital discharge. CONCLUSION: Quantification of pneumonia features on admitting chest CT predicted hypoxia worsening during hospitalization and time to hospital discharge in COVID-19 patients.

Echocardiography in Pandemic: Front-Line Perspective, Expanding Role of Ultrasound, and Ethics of Resource Allocation.

The grave clinical context of the coronavirus disease 2019 (COVID-19) pandemic must be understood. Italy is immersed in the COVID-19 pandemic. Most of the world will soon follow. The United States currently has the most documented cases of COVID-19 of any nation. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-associated acute cardiomyopathy is common in critical care patients and is associated with a high mortality rate. Patients with COVID-19 frequently require mechanical support for adequate oxygenation. A severe shortfall of ventilators is predicted. Of equal concern is the projected shortage of trained professionals required to care for patients on mechanical ventilation. Ultrasonography is proving to be a valuable tool for identifying the pulmonary manifestations and progression of COVID-19. Lung ultrasound also facilitates successful weaning from mechanical ventilation. Ultrasonography of the lung, pleura, and diaphragm are easily mastered by experienced echocardiographers. Echocardiography has an established role for optimal fluid management and recognition of cardiac disease, including SARS-CoV-2-associated acute cardiomyopathy. Cardiologists, anesthesiologists, sonographers, and all providers should be prepared to commit their full spectrum of skills to mitigate the consequences of the pandemic. We should also be prepared to collaborate and cross-train to expand professional services as necessary. During a declared health care crisis, providers must be familiar with the ethical principles, organizational structure, practical application, and gravity of limited resource allocation.

Editor's Choice - A Rotational Thromboelastometry Driven Transfusion Strategy Reduces Allogenic Blood Transfusion During Open Thoraco-abdominal Aortic Aneurysm Repair: A Propensity Score Matched Study.

OBJECTIVE: Open repair of thoraco-abdominal aortic aneurysm (TAAA) is a challenging procedure, associated with high rates of peri-operative bleeding and blood product transfusions. A large intra-operative volume transfusion has been associated with higher in hospital mortality and prolonged mechanical ventilation. A propensity score matched study was carried out to assess whether the introduction of a rotational thromboelastometry (ROTEM) based transfusion strategy reduces allogenic blood transfusion and affects morbidity in patients undergoing open TAAA repair. METHODS: All patients undergoing open TAAA repair at the San Raffaele Scientific Institute between 2009 and 2017 were included. Until 2016, a protocol based on estimated blood loss and conventional coagulation tests was used. After March 2016 a ROTEM guided transfusion protocol was developed and adopted. To account for selection bias, propensity score matching was performed. RESULTS: Five hundred and forty-seven consecutive patients were included. After propensity score matching, 77 patients in the ROTEM algorithm group were successfully matched with 77 patients in the standard algorithm group. Patients managed with ROTEM received fewer red blood cells units (3.5 [range 0-11] vs. 4 [range 0-17]; p = .026) and a lower volume of fresh frozen plasma (286 ± 496 vs. 2,050 ± 1,120; p < .001). In addition, fewer patients received fresh frozen plasma (35% vs. 97%; p < .001). Patients in the ROTEM group showed a significant decrease in the occurrence of pulmonary complications (44% vs. 83%; p = .01). Cost analysis showed a relevant reduction of per-patient expense after the introduction of ROTEM (€834 ± €577 vs. €1,285 ± €851; p < .001) CONCLUSION: A ROTEM guided transfusion strategy significantly limited the quantity of transfused blood products during open TAAA repair, improving clinical outcomes while reducing costs, allowing for better resource distribution in a setting where blood loss is relevant.

Assessment of diaphragmatic dysfunction in the critically ill patient with ultrasound: a systematic review.

PURPOSE: Diaphragmatic dysfunction (DD) has a high incidence in critically ill patients and is an under-recognized cause of respiratory failure and prolonged weaning from mechanical ventilation. Among different methods to assess diaphragmatic function, diaphragm ultrasonography (DU) is noninvasive, rapid, and easy to perform at the bedside. We systematically reviewed the current literature assessing the usefulness and accuracy of DU in intensive care unit (ICU) patients. METHODS: Pubmed, Cochrane Database of Systematic Reviews, Embase, Scopus, and Google Scholar Databases were searched for pertinent studies. We included all original, peer-reviewed studies about the use of DU in ICU patients. RESULTS: Twenty studies including 875 patients were included in the final analysis. DU was performed with different techniques to measure diaphragmatic inspiratory excursion, thickness of diaphragm (Tdi), and thickening fraction (TF). DU is feasible, highly reproducible, and allows one to detect diaphragmatic dysfunction in critically ill patients. During weaning from mechanical ventilation and spontaneous breathing trials, both diaphragmatic excursion and diaphragmatic thickening measurements have been used to predict extubation success or failure. Optimal cutoffs ranged from 10 to 14 mm for excursion and 30-36 % for thickening fraction. During assisted mechanical ventilation, diaphragmatic thickening has been found to be an accurate index of respiratory muscles workload. Observational studies suggest DU as a reliable method to assess diaphragm atrophy in patients undergoing mechanical ventilation. CONCLUSIONS: Current literature suggests that DU could be a useful and accurate tool to detect diaphragmatic dysfunction in critically ill patients, to predict extubation success or failure, to monitor respiratory workload, and to assess atrophy in patients who are mechanically ventilated.

A Bayesian network meta-analysis for binary outcome: how to do it.

This study presents an overview of conceptual and practical issues of a network meta-analysis (NMA), particularly focusing on its application to randomised controlled trials with a binary outcome of interest. We start from general considerations on NMA to specifically appraise how to collect study data, structure the analytical network and specify the requirements for different models and parameter interpretations, with the ultimate goal of providing physicians and clinician-investigators a practical tool to understand pros and cons of NMA. Specifically, we outline the key steps, from the literature search to sensitivity analysis, necessary to perform a valid NMA of binomial data, exploiting Markov Chain Monte Carlo approaches. We also apply this analytical approach to a case study on the beneficial effects of volatile agents compared to total intravenous anaesthetics for surgery to further clarify the statistical details of the models, diagnostics and computations. Finally, datasets and models for the freeware WinBUGS package are presented for the anaesthetic agent example.

Cardiac index assessment by the pressure recording analytic method in critically ill unstable patients after cardiac surgery.

OBJECTIVE: The authors measured cardiac index in unstable patients after cardiac surgery with the Pressure Recording Analytic Method (PRAM) and compared it with the reference method of thermodilution (ThD) with the pulmonary artery catheter; using the hypothesis that there were no significant differences between the 2 methods. DESIGN: A prospective study. SETTING: Cardiac surgery intensive care unit in a teaching hospital. PARTICIPANTS: Ninety-four measurements from 59 patients with ongoing high doses of inotropic drugs and/or an intra-aortic balloon pump for low-cardiac-output syndrome after cardiac surgery were studied. INTERVENTIONS: The pulmonary artery catheter and the radial or femoral arterial catheter for measuring blood pressure were already in place for standard hemodynamic monitoring. MEASUREMENTS AND MAIN RESULTS: The mean of the total CI measurements was 2.94 ± 0.67 L/min/m(2) with PRAM and 2.95 ± 0.63 L/min/m(2) with ThD, with no significant difference according to the linear mixed models analysis. The PRAM and ThD techniques were similar in unstable patients without atrial fibrillation (mean bias 0.047 ± 0.395 L/min/m(2) and a percentage error of 29%), while no agreement between PRAM and ThD was found in unstable patients with atrial fibrillation (mean bias 0.195 ± 0.885 L/min/m(2) and a percentage error of 69%). CONCLUSION: Cardiac index measurements after cardiac surgery performed with PRAM and with ThD showed a good agreement in hemodynamically unstable patients given high doses of inotropes and/or an IABP in patients in sinus rhythm, but not in those with atrial fibrillation.

Dynamic assessment of 'valvular reserve capacity' in patients with rheumatic mitral stenosis.

AIMS: Mitral stenosis (MS) may exhibit a dynamic valvular reserve. When resting gradients and systolic pulmonary pressure (sPAP) do not reflect the real severity of the disease, a dynamic evaluation becomes necessary. The aim of the study was to assess the clinical utility of exercise echocardiography in symptomatic patients with apparently subcritical MS. METHODS AND RESULTS: One hundred and thirty consecutive patients were referred for symptomatic MS. Patients with unimpressive resting MVA (>1-1.5 cm(2)) and mean PG (≥5-9 mmHg) underwent exercise echocardiography. Cardiac performance and mitral indices (MVA, peak/mean PG, sPAP) were measured. Exhaustion of valvular reserve capacity under exercise was defined as appearance of symptoms and sPAP > 60 mmHg. Forty-six patients (35%) (age: 53 ± 10 years; 74%, female) with resting MVA (1.2 ± 0.36 cm(2)), mean PG (6.8 ± 2.7 mmHg), and sPAP (38 ± 7 mmHg) inconsistent with symptoms underwent stress echocardiography. Exercise was stopped for dyspnoea (76%) or fatigue (24%). At peak workloads (57.2 ± 21.8 Watts), increased mean PG (17.2 ± 4.8 mmHg, P< 0.001) and sPAP (67.4 ± 11.4 mmHg; P< 0.0001) were observed, without change in MVA (1.25 ± 0.4 cm(2); P= n.s.). At univariate analysis, predictors of adaptation to exercise were age (-0.345; P = 0.024), mean PG (0.339; P= 0.023), and sPAP (0.354; P= 0.024); at multivariate analysis, best predictor was resting mean PG, although correlation was poor (-0.339; P= 0.015). CONCLUSION: In MS with limiting symptoms despite unimpressive findings at rest, valvular capacity exhaustion should be tested on a dynamic background, as no single resting index can predict potential haemodynamic adaptation to exercise. In such context, the contribution of exercise echocardiography remains extremely valuable.

Cardiac index assessment by the pressure recording analytic method in unstable patients with atrial fibrillation.

OBJECTIVE: Most-Care (powered by the pressure-recording analytic method [PRAM]; Vytech HealthTM, Padova, Italy) is a minimally invasive cardiac output monitoring. This system already has been studied and validated in cardiac surgery and in children. It already showed a correlation with thermodilution methods in hemodynamically unstable patients. The purpose of this study was to confirm the reliability of cardiac index determinations by Most-Care in unstable patients with atrial fibrillation. DESIGN: A prospective study. SETTING: A teaching hospital. PARTICIPANTS: Forty-nine patients. INTERVENTIONS: Simultaneous cardiac index measurements by bolus thermodilution and by PRAM from a standard arterial access (radial and femoral) were obtained. The thermodilution cardiac index was calculated as the mean of 3 separate measurements. Because PRAM is a beat-to-beat monitoring system, the mean cardiac index of 12 consecutive beats was considered for the analysis. Correlations were calculated and differences compared by Bland-Altman analysis. MEASUREMENTS: Eight patients were excluded because the signal was altered by the arterial catheter resonance so that the study described the remaining 41 patients. The overall estimates of cardiac index measured by PRAM did not show agreement with the reference cardiac index by thermodilution (mean difference = 0.136 L/min/m(2) [0,43 L/min/m(2)-0.15 L/min/m(2)], with an upper limit of agreement of 1.94 L/min/m(2) and a lower limit of agreement of -1.665 L/min/m(2), respectively). The median (interquartile) value of cardiac index assessed by thermodilution was 2.42 L/min/m(2) (2.21-2.98 L/min/m(2)), and by PRAM it was 2.48 L/min/m(2) (1.80-3.00 L/min/m(2), p = 0.6). CONCLUSIONS: The authors concluded that PRAM did not compare well with thermodilution in unstable patients with atrial fibrillation.