The Predictive Validity of the Berlin Definition of Acute Respiratory Distress Syndrome for Patients With COVID-19-Related Respiratory Failure Treated With High-Flow Nasal Oxygen: A Multicenter, Prospective Cohort Study.

OBJECTIVES: The Berlin definition of acute respiratory distress syndrome (ARDS) was constructed for patients receiving invasive mechanical ventilation (IMV) with consideration given to issues related to reliability, feasibility, and validity. Notwithstanding, patients with acute respiratory failure (ARF) may be treated with high-flow nasal oxygen (HFNO) and may not fall within the scope of the original definition. We aimed to evaluate the predictive validity of the Berlin definition in HFNO-treated patients with COVID-19-related respiratory failure who otherwise met ARDS criteria. DESIGN: Multicenter, prospective cohort study. SETTING: Five ICUs of five centers in Argentina from March 2020 to September 2021. PATIENTS: We consecutively included HFNO-treated patients older than 18 years with confirmed COVID-19-related ARF, a Pa o2 /F io2 of less than 300 mm Hg, bilateral infiltrates on imaging, and worsening respiratory symptoms for less than 1 week. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We evaluated the predictive validity of mortality at day 28 using the area under the receiver operating characteristics curve (AUC), compared the predictive validity across subgroups, and characterized relevant clinical outcomes. We screened 1,231 patients and included 696 ARDS patients [30 (4%) mild, 380 (55%) moderate, and 286 (41%) severe]. For the study cohort, the AUC for mortality at day 28 was 0.606 (95% CI, 0.561-0.651) with the AUC for subgroups being similar to that of the overall cohort. Two hundred fifty-six patients (37%) received IMV. By day 28, 142 patients (21%) had died, of whom 81 (57%) had severe ARDS. Mortality occurred primarily in patients who were transitioned to IMV. CONCLUSIONS: The predictive validity of the Berlin ARDS definition was similar for HFNO-treated patients as compared with the original population of invasively ventilated patients. Our findings support the extension of the Berlin definition to HFNO-treated patients with ARDS.

Pressure- vs. volume-controlled ventilation and their respective impact on dynamic parameters of fluid responsiveness: a cross-over animal study.

BACKGROUND AND GOAL OF STUDY: Pulse pressure variation (PPV) and stroke volume variation (SVV), which are based on the forces caused by controlled mechanical ventilation, are commonly used to predict fluid responsiveness. When PPV and SVV were introduced into clinical practice, volume-controlled ventilation (VCV) with tidal volumes (VT) ≥ 10 ml kg- 1 was most commonly used. Nowadays, lower VT and the use of pressure-controlled ventilation (PCV) has widely become the preferred type of ventilation. Due to their specific flow characteristics, VCV and PCV result in different airway pressures at comparable tidal volumes. We hypothesised that higher inspiratory pressures would result in higher PPVs and aimed to determine the impact of VCV and PCV on PPV and SVV. METHODS: In this self-controlled animal study, sixteen anaesthetised, paralysed, and mechanically ventilated (goal: VT 8 ml kg- 1) pigs were instrumented with catheters for continuous arterial blood pressure measurement and transpulmonary thermodilution. At four different intravascular fluid states (IVFS; baseline, hypovolaemia, resuscitation I and II), ventilatory and hemodynamic data including PPV and SVV were assessed during VCV and PCV. Statistical analysis was performed using U-test and RM ANOVA on ranks as well as descriptive LDA and GEE analysis. RESULTS: Complete data sets were available of eight pigs. VT and respiratory rates were similar in both forms. Heart rate, central venous, systolic, diastolic, and mean arterial pressures were not different between VCV and PCV at any IVFS. Peak inspiratory pressure was significantly higher in VCV, while plateau, airway and transpulmonary driving pressures were significantly higher in PCV. However, these higher pressures did not result in different PPVs nor SVVs at any IVFS. CONCLUSION: VCV and PCV at similar tidal volumes and respiratory rates produced PPVs and SVVs without clinically meaningful differences in this experimental setting. Further research is needed to transfer these results to humans.

A Randomized Trial of Convalescent Plasma in Covid-19 Severe Pneumonia.

BACKGROUND: Convalescent plasma is frequently administered to patients with Covid-19 and has been reported, largely on the basis of observational data, to improve clinical outcomes. Minimal data are available from adequately powered randomized, controlled trials. METHODS: We randomly assigned hospitalized adult patients with severe Covid-19 pneumonia in a 2:1 ratio to receive convalescent plasma or placebo. The primary outcome was the patient's clinical status 30 days after the intervention, as measured on a six-point ordinal scale ranging from total recovery to death. RESULTS: A total of 228 patients were assigned to receive convalescent plasma and 105 to receive placebo. The median time from the onset of symptoms to enrollment in the trial was 8 days (interquartile range, 5 to 10), and hypoxemia was the most frequent severity criterion for enrollment. The infused convalescent plasma had a median titer of 1:3200 of total SARS-CoV-2 antibodies (interquartile range, 1:800 to 1:3200). No patients were lost to follow-up. At day 30 day, no significant difference was noted between the convalescent plasma group and the placebo group in the distribution of clinical outcomes according to the ordinal scale (odds ratio, 0.83; 95% confidence interval [CI], 0.52 to 1.35; P = 0.46). Overall mortality was 10.96% in the convalescent plasma group and 11.43% in the placebo group, for a risk difference of -0.46 percentage points (95% CI, -7.8 to 6.8). Total SARS-CoV-2 antibody titers tended to be higher in the convalescent plasma group at day 2 after the intervention. Adverse events and serious adverse events were similar in the two groups. CONCLUSIONS: No significant differences were observed in clinical status or overall mortality between patients treated with convalescent plasma and those who received placebo. (PlasmAr ClinicalTrials.gov number, NCT04383535.).

Prevención de hemorragias en el posoperatorio temprano de cirugía bariátrica: Papel de la vitamina K / Prevention of hemorrhage in the early postoperative period of bariatric surgery: Role of vitamin K

Introducción: la cirugía bariátrica es el tratamiento más eficaz para la obesidad mórbida. La hemorragia se presenta en el 0,5-5% de las pacientes. La preparación prequirúrgica con dieta líquida y el uso de antibióticos para Helicobacter pylori podría alterar el metabolismo de la vitamina K y asociarse a hemorragia. Objetivo: describir el comportamiento de la concentración de protrombina (basal = B-PT y prequirúrgica = preQ-PT) en estos pacientes. Material y métodos: se realizó un estudio de cohorte prospectivo donde se comparó la concentración de B-PT (15-180 días previos a la cirugía) y la preQ-PT (24 horas previas a la cirugía). Resultados: se incluyeron 194 pacientes, de los cuales el 72% (n = 139) fueron mujeres, de entre 19 y 69 años, con BMI (IMC) 45 (33 a 58) y pérdida de peso prequirúrgica del 7% (-2 a 17). El promedio de B-PT fue 91,9% (DE 9,529), el promedio de la preQ-PT fue 81,1% (DE 10,760); descendió un 10,8% (p < 0,001). No hubo diferencias significativas cuando se comparó el comportamiento en la preQ-PT entre los diferentes subgrupos (uso de antibióticos para Helicobacter pylori, de acuerdo con la pérdida de peso y en relación con la suplementación de vitamina K); sin embargo, siempre se detectó descenso de la preQ-PT. No hubo ninguna complicación hemorrágica (necesidad de transfusiones o reoperación); tampoco hubo muerte por hemorragias ni eventos tromboembólicos. Conclusión: realizar dosaje de protrombina 24 horas antes de la cirugía bariátrica permite detectar alteraciones iatrogénicas de la coagulación inducidas por la dieta y el uso de antibióticos.

Background: bariatric surgery is the most efficient treatment for morbid obesity. Bleeding occurs in 0.5-5% of patients. Pre-surgical preparation with liquid diet and the use of antibiotics for Helicobacter pylori could alter the metabolism of vitamin K and be associated with hemorrhage. Objective: to describe the behavior of the concentration of Prothrombin (basal = B-PT and pre-surgical = preQ-PT) in these patients. Material and methods: a prospective cohort study comparing B-PT concentration (15-180 days prior to surgery) and preQ-PT (24 h prior to surgery) was performed. Results: a total of 194 patients were included in the study, with 72% (n = 139) women aged 19-69 years, BMI 45 (33 to 58) and preoperative weight loss of 7% (-2 to 17). The media B-PT was 91.9% (SD 9.529), the media pre-PT was 81.1% (SD 10.760); declined 10.8% (p <0.001). There was no significant difference when comparing the behavior in the preQ-PT among different subgroups (use of antibiotics for Helicobacter pylori, according to weight loss and in relation to vitamin K supplementation), however, there was always a decrease of the preQ-PT. There were no bleeding complications (need for transfusions or re-intervetion), nor was there death for bleeding or thromboembolic events. Conclusion: prothrombin measurement 24 hours before bariatric surgery allows the detection of iatrogenic coagulation alterations induced by diet and the use of antibiotics.

[Continuing medical education: a clinical research institutional project]. / Proyecto institucional para la educación médica continua en investigación clínica.

In Argentina, education in clinical investigation is based on courses with theoric content. In developed countries programs with ongoing and practical content exist, generating the proper context to learn. In 2006, the Hospital Italiano de Buenos Aires (HIBA) created an area to train physicians, Research Area in Internal Medicine, and enable them to participate in every step of the clinical investigation process. The objective of this study is to describe this teaching area and its impact on the investigation in Internal Medicine in the HIBA, in the period 2006-2008. This area counts with fellow positions and provides training in Clinical Investigation for rotating residents. It has different activities including lectures, project counseling and 3 ongoing Institutional Registers for prevalent medical problems, 33% (6/18) of Intern staff are currently participating, with 3 fellows and 7 monitors for the Registers; 25 residents rotated in the area and generated their own research projects. 59 posters were presented in local and international congresses. Currently 6 original articles are in process of publication and 2 in peer review evaluation. A survey was carried out to evaluate the area where 76% (35/46) of the participants believed that they have acquired new skills; with 93% (44/47) using these knowledges in their every day practice. A 100% thought that they were adequately oriented in their projects, their ideas being fully respected (97%) (45/46). The inclusion of the Research Area in Internal Medicine improved the knowledge of the process of clinical Investigation and increased independent scientific production.

Proyecto institucional para la educación médica continua en investigación clínica / Continuing medical education: A clinical research institutional project

En la Argentina, educar en investigación clínica consiste principalmente en cursos teóricos. En países desarrollados existen programas que generan el entorno propicio para un aprendizaje práctico y continuo. En el 2006, en el Servicio de Clínica Médica del Hospital Italiano de Buenos Aires se creó el Área de Investigación en Medicina Interna para formar profesionales capaces de participar en todas las etapas de la investigación clínica. El propósito de este estudio es describir el área y su impacto en la educación en investigación en medicina interna durante el período 2006-2008. El proyecto cuenta con un programa de capacitación en investigación clínica para residentes y otro de perfeccionamiento para becarios. Además de becas, asesoramiento en proyectos, ateneos sobre investigación clínica y registros de enfermedades prevalentes en medicina interna. Participan el 33% (6/18) de los clínicos de internación, se encuentran en formación 3 becarios y 7 monitores de investigación. 25 residentes pasaron por el programa de capacitación, completaron una propuesta de investigación 19 (76%). Se hicieron 59 presentaciones en congresos. Se encuentran en proceso de publicación 6 artículos originales y 2 en revisión por comités editoriales. De un cuestionario de evaluación del área, el 76% (35/46) considera que ha adquirido nuevas habilidades, y 93% (44/47) refiere que las utiliza en la práctica diaria. El 100% (47/47) considera que ha recibido orientación adecuada. El 97% (45/46) considera que sus ideas han sido respetadas. La implementación del área de investigación logró aumentar la capacitación y producción científica en investigación clínica independiente.

In Argentina, education in clinical investigation is based on courses with theoric content. In developed countries programs with ongoing and practical content exist, generating the proper context to learn. In 2006, the Hospital Italiano de Buenos Aires (HIBA) created an area to train physicians, Research Area in Internal Medicine, and enable them to participate in every step of the clinical investigation process. The objective of this study is to describe this teaching area and its impact on the investigation in Internal Medicine in the HIBA, in the period 2006-2008. This area counts with fellow positions and provides training in Clinical Investigation for rotating residents. It has different activities including lectures, project counseling and 3 ongoing Institutional Registers for prevalent medical problems, 33% (6/18) of Intern staff are currently participating, with 3 fellows and 7 monitors for the Registers; 25 residents rotated in the area and generated their own research projects. 59 posters were presented in local and international congresses. Currently 6 original articles are in process of publication and 2 in peer review evaluation. A survey was carried out to evaluate the area where 76% (35/46) of the participants believed that they have acquired new skills; with 93% (44/47) using these knowledges in their every day practice. A 100% thought that they were adequately oriented in their projects, their ideas being fully respected (97%) (45/46). The inclusion of the Research Area in Internal Medicine improved the knowledge of the process of clinical Investigation and increased independent scientific production.