Physiological effect of high flow oxygen therapy measured by electrical impedance tomography in single-lung transplantation / Efectos fisiológicos del alto flujo de oxígeno medido por tomografía de impedancia eléctrica en trasplante unipulmonar

Abstract In patients with chronic obstructive pulmonary dis ease (COPD), single lung transplantation (SLT) is some times performed as an alternative to bilateral lung trans plantation due to limited organ availability. However, the postoperative management of SLT presents challenges, including complications related to the distinct compli ance of each lung. This case report presents the case of a 65-year-old male patient who underwent SLT and was in the weaning period from mechanical ventilation. High-flow oxygen therapy (HFOT) was administered, and the physiological effects were measured using electrical impedance tomography (EIT). The results demonstrated that the application of HFOT increased air trapping and overdistention in the native lung without benefiting the transplanted lung. HFOT through a tracheostomy tube or nasal cannula resulted in a more heterogeneous distri bution of ventilation, with increased end expiratory lung impedance, prolonged expiratory time constants, and an increase in silent spaces. The drop in tidal impedance after applying HFOT did not indicate hypoventilation but rather overdistention and air trapping in the native lung, while the transplanted lung showed evidence of hypoventilation. These findings suggest that HFOT may not be beneficial for SLT patients and could potentially worsen outcomes. However, due to the limited scope of this case report, further prospective studies with larger patient cohorts are needed to confirm these results.

Resumen En pacientes con enfermedad pulmonar obstructiva crónica (EPOC), el trasplante pulmonar unilateral (SLT, por sus siglas en inglés) se realiza como alternativa a la disponibilidad limitada de donantes para el trasplante pulmonar bilateral. Sin embargo, el manejo postoperato rio del SLT presenta desafíos, incluyendo complicaciones relacionadas con la distinta complacencia de cada pul món. Este reporte presenta el caso de un paciente varón de 65 años que fue sometido a un SLT y se encontraba en el proceso de destete de la ventilación mecánica. Se administró terapia de oxígeno de alto flujo (HFOT, por sus siglas en inglés) y se midieron los efectos fisiológicos utilizando la tomografía de impedancia eléctrica (EIT, por sus siglas en inglés). Los resultados demostraron que la aplicación de HFOT aumentó la retención de aire y la hiperinflación en el pulmón nativo sin beneficiar al pulmón trasplantado. Tanto la HFOT a través de un tubo de traqueostomía como a través de cánula nasal resultaron en una distribución más heterogénea de la ventilación, con un aumento en la impedancia pulmonar al final de la espiración, prolongación de las constantes de tiempo espiratorias y un aumento en los espacios silentes. La disminución de la impedancia tidal después de aplicar HFOT no indicó hipoventilación, sino más bien hiperinsuflación y retención de gas en el pulmón nativo, mientras que el pulmón trasplantado mostró evidencia de hipoventilación. Estos hallazgos sugieren que el HFOT puede no ser beneficioso para los pacientes con SLT y podría empeorar los resultados. Sin embargo, debido al alcance limitado de este informe de caso, se necesitan estudios prospectivos con cohortes de pacientes más amplias para confirmar estos resultados.

Clinical characteristics of critically ill patients with COVID-19 / Características clínicas de los pacientes críticos con COVID-19

Abstract Coronavirus disease 2019 (COVID-19) pandemic poses a major challenge for healthcare systems. In South America, local information about the incidence and clinical characteristics of critically ill patients diagnosed with COVID-19 is still limited. In this observational and retrospective study, we aimed to de scribe critically ill patients' clinical and respiratory characteristics with COVID-19. The study was performed over 6 months in an intensive care unit (ICU) of a high complexity hospital in Buenos Aires, Argentina. Patients older than 18 years with laboratory-confirmed COVID-19 by reverse tran scriptase-polymerase chain reaction (RT-PCR) for SARS-CoV-2 were included in the study. Demographic characteristics such as sex and age, comorbidities, laboratory results, imaging results, ventilatory mechanics data, complications, and mortality were recorded. A total of 168 critically ill patients with COVID-19 were included. Sixty-six percent were men with a median age of 65 years (58-75); 79.7% had at least one comorbidity. The most frequent comorbidity was arterial hypertension, affecting 52.4%. A 67.9% required invasive mechanical ventilation (MV), and no one was treated with non-invasive ventilation. Most of the patients in MV (73.7%) required neuromuscular blockade due to severe hypoxemia. A 36% was ventilated in the prone position. The length of stay in the ICU was 13 days (6-24) and ICU's mortality was 25%.

Resumen La pandemia de la enfermedad por coronavirus 2019 (COVID-19) plantea un gran desafío para los sistemas de salud. En América del Sur, la información local sobre la incidencia y las características clínicas de los pacientes crítica mente enfermos diagnosticados con COVID-19 aún es limitada. En este estudio observacional y retrospectivo, nuestro objetivo fue describir las características clínicas y respiratorias de los pacientes críticamente enfermos con COVID-19. El estudio se realizó durante 6 meses en una unidad de cuidados intensivos (UCI) de un hospital de alta complejidad en Buenos Aires, Argentina. Se incluyeron en el estudio pacientes mayores de 18 años con COVID-19 confirmado por laboratorio mediante la reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR) para SARS-CoV-2. Se registraron características demográficas como sexo y edad, comorbilidades, resultados de laboratorio, resultados de imagen, datos de mecánica ventilatoria, complicaciones y mortalidad. Se incluyeron un total de 168 pacientes críticamente enfermos con COVID-19. El 66% eran hombres con una mediana de edad de 65 años (58-75). El 79.7% presentaba al menos una comorbilidad. La comorbilidad más frecuente fue la hipertensión arterial, afectando al 52.4%. El 67.9% requirió ventilación mecánica invasiva (VM) y ninguno fue tratado con ventilación no invasiva. La mayoría de los pacientes en VM (73.7%) requirieron bloqueo neuromuscular por hipoxemia grave. Un 36% de ellos fueron ventilados en decúbito prono. La estancia en UCI fue de 13 días (6-24) y la mortalidad en UCI fue del 25%.

Modificações no manejo e desfechos clínicos de pacientes críticos sem COVID-19 durante a pandemia / Changes in the management and clinical outcomes of critically ill patients without COVID-19 during the pandemic

RESUMO Objetivo: Analisar se as modificações na atenção médica em razão da aplicação dos protocolos para COVID-19 afetaram os desfechos clínicos de pacientes sem a doença durante a pandemia. Métodos: Este foi um estudo observacional de coorte retrospectiva conduzido em uma unidade de terapia intensiva clínica e cirúrgica com 38 leitos, localizada em hospital privado de alta complexidade na cidade de Buenos Aires, Argentina, e envolveu os pacientes com insuficiência respiratória admitidos à unidade de terapia intensiva no período compreendido entre março e abril de 2020 em comparação com o mesmo período no ano de 2019. Compararam-se as intervenções e os desfechos dos pacientes sem COVID-19 tratados durante a pandemia em 2020 e os pacientes admitidos em 2019. As principais variáveis avaliadas foram os cuidados respiratórios na unidade de terapia intensiva, o número de exames de tomografia computadorizada do tórax e lavados broncoalveolares, complicações na unidade de terapia intensiva e condições quando da alta hospitalar. Resultados: Observou-se, em 2020, uma redução significante do uso de cânula nasal de alto fluxo: 14 (42%), em 2019, em comparação com 1 (3%), em 2020. Além disso, em 2020, observou-se aumento significante no número de pacientes sob ventilação mecânica admitidos à unidade de terapia intensiva a partir do pronto-socorro, de 23 (69%) em comparação com 11 (31%) em 2019. Contudo, o número de pacientes com ventilação mecânica 5 dias após a admissão foi semelhante em ambos os anos: 24 (69%), em 2019, e 26 (79%) em 2020. Conclusão: Os protocolos para unidades de terapia intensiva com base em recomendações internacionais para a pandemia de COVID-19 modificaram o manejo de pacientes sem COVID-19. Observamos redução do uso da cânula nasal de alto fluxo e aumento no número de intubações traqueais no pronto-socorro. Entretanto, não se identificaram alterações na percentagem de pacientes intubados na unidade de terapia intensiva, número de dias sob ventilação mecânica ou número de dias na unidade de terapia intensiva.

Abstract Objective: To analyze whether changes in medical care due to the application of COVID-19 protocols affected clinical outcomes in patients without COVID-19 during the pandemic. Methods: This was a retrospective, observational cohort study carried out in a thirty-eight-bed surgical and medical intensive care unit of a high complexity private hospital. Patients with respiratory failure admitted to the intensive care unit during March and April 2020 and the same months in 2019 were selected. We compared interventions and outcomes of patients without COVID-19 during the pandemic with patients admitted in 2019. The main variables analyzed were intensive care unit respiratory management, number of chest tomography scans and bronchoalveolar lavages, intensive care unit complications, and status at hospital discharge. Results: In 2020, a significant reduction in the use of a high-flow nasal cannula was observed: 14 (42%) in 2019 compared to 1 (3%) in 2020. Additionally, in 2020, a significant increase was observed in the number of patients under mechanical ventilation admitted to the intensive care unit from the emergency department, 23 (69%) compared to 11 (31%) in 2019. Nevertheless, the number of patients with mechanical ventilation after 5 days of admission was similar in both years: 24 (69%) in 2019 and 26 (79%) in 2020. Conclusion: Intensive care unit protocols based on international recommendations for the COVID-19 pandemic have produced a change in non-COVID-19 patient management. We observed a reduction in the use of a high-flow nasal cannula and an increased number of tracheal intubations in the emergency department. However, no changes in the percentage of intubated patients in the intensive care unit, the number of mechanical ventilation days or the length of stay in intensive care unit.

Traqueobronquitis necrotizante secundaria a aspergilosis invasiva en paciente inmunocompetente / Necrotizing tracheobronchitis due to invasive aspergillosis in an immunocompetent patient

Resumen La traqueobronquitis aspergilar es una forma poco frecuente de aspergilosis invasiva reportada excepcionalmente en el paciente inmunocompetente. Su diagnóstico es difícil, y los tratamientos propuestos hasta ahora son de escasa efectividad, todo lo cual constituye un verdadero problema para el equipo de salud. Presentamos el caso de una paciente de 28 años, inmunocompetente y sin antecedentes epidemiológicos, que desarrolló traqueobronquitis necrotizante por aspergilosis invasiva y recibió tratamiento con voriconazol con instilación local por broncoscopia con buena respuesta.

Abstract Aspergillus tracheobronchitis is a rare form of invasive aspergillosis reported exceptionally in the immunocompetent patient. Its diagnosis is difficult, and the treatments proposed so far are of little effectiveness, all of which constitute a real problem for the health team. We present the case of an immunocompetent 28 yearsold woman, with no epidemiological background, who developed necrotizing tracheobronchitis due to invasive aspergillosis and received voriconazole with local instillation by bronchoscopy with a good response.