Papel de la ecografía en la insuficiencia respiratoria aguda y en el weaning de la ventilación mecánica

Resumen La evaluación integral mediante ecografía se ha convertido en una herramienta indispensable para facilitar el diagnóstico y el manejo terapéutico en los pacientes críticos con insuficiencia respiratoria aguda (IRA). Existe evidencia que apoya el uso de la ecografía para el diagnóstico de neumotórax, síndrome de distrés respiratorio agudo, edema pulmonar cardiogénico, neumonía, tromboembolismo pulmonar agudo y el paciente con COVID-19. Además, en los últimos años se ha desarrollado el uso de la ecografía para evaluar la respuesta a los tratamientos en los pacientes críticos con IRA, brindando una herramienta no invasiva para la titulación de la presión positiva al final de la espiración, monitorizar las maniobras de reclutamiento y la respuesta al prono, así como para facilitar la retirada de la ventilación mecánica. El objetivo de esta revisión es resumir los conceptos básicos sobre la utilidad de la ecografía en el diagnóstico y la monitorización de los pacientes críticos con IRA. Comprehensive ultrasound assessment has become an essential tool to facilitate diagnosis and therapeutic management in critically ill patients with acute respiratory failure (ARF). There is evidence supporting the use of ultrasound for the diagnosis of pneumothorax, acute respiratory distress syndrome, cardiogenic pulmonary edema, pneumonia, acute pulmonary thromboembolism, and the patient with COVID-19. In addition, in recent years, the use of ultrasound to evaluate response to treatments in critically ill patients with ARF has been developed, providing a non-invasive tool for titrating positive end-expiratory pressure, monitoring recruitment maneuvers and response to prone, as well as to facilitate weaning from mechanical ventilation. The objective of this review is to summarize the basic concepts on the utility of ultrasound in the diagnosis and monitoring of critically ill patients with ARF.

Lung ultrasound response to awake prone positioning predicts the need for intubation in patients with COVID-19 induced acute hypoxemic respiratory failure: an observational study.

BACKGROUND: Awake prone positioning (APP) reduces the intubation rate in COVID-19 patients treated by high-flow nasal cannula (HFNC). However, the lung aeration response to APP has not been addressed. We aimed to explore the lung aeration response to APP by lung ultrasound (LUS). METHODS: This two-center, prospective, observational study enrolled patients with COVID-19-induced acute hypoxemic respiratory failure treated by HFNC and APP. LUS score was recorded 5-10 min before, 1 h after APP, and 5-10 min after supine in the first APP session within the first three days. The primary outcome was LUS score changes in the first three days. Secondary outcomes included changes in SpO2/FiO2 ratio, respiratory rate and ROX index (SpO2/FiO2/respiratory rate) related to APP, and the rate of treatment success (patients who avoided intubation). RESULTS: Seventy-one patients were enrolled. LUS score decreased from 20 (interquartile range [IQR] 19-24) to 19 (18-21) (p < 0.001) after the first APP session, and to 19 (18-21) (p < 0.001) after three days. Compared to patients with treatment failure (n = 20, 28%), LUS score reduction after the first three days in patients with treatment success (n = 51) was greater (- 2.6 [95% confidence intervals - 3.1 to - 2.0] vs 0 [- 1.2 to 1.2], p = 0.001). A decrease in dorsal LUS score > 1 after the first APP session was associated with decreased risk for intubation (Relative risk 0.25 [0.09-0.69]). APP daily duration was correlated with LUS score reduction in patients with treatment success, especially in dorsal lung zones (r = - 0.76; p < 0.001). CONCLUSIONS: In patients with acute hypoxemic respiratory failure due to COVID-19 and treated by HFNC, APP reduced LUS score. The reduction in dorsal LUS scores after APP was associated with treatment success. The longer duration on APP was correlated with greater lung aeration. Trial registration This study was prospectively registered on clinicaltrials.gov on April 22, 2021. Identification number NCT04855162 .

Echocardiographic assessment of COVID19 sequelae in survivors with elevated cardiac biomarkers.

AIMS: We sought to determine, using advanced echocardiography, the prevalence and type of cardiovascular sequelae after COVID19 infection with marked elevation of cardiovascular biomarkers (CVB), and their prognostic implications. METHODS: All patients admitted from March 1st to May 25th, 2020 to a tertiary referral hospital were included. Those with cardiovascular diseases or dead during admission were excluded. Patients with hs-TnI > 45 ng/L, NT-proBNP>300 pg/mL, and D-dimer >8000 ng/mL were matched with COVID controls (three biomarkers within the normal range) based on intensive care requirements and age, and separately analyzed. RESULTS: From 2025 patients, 80 patients with significantly elevated CVB and 29 controls were finally included. No differences in baseline characteristics were observed among groups, but elevated CVB patients were sicker. Follow-up echocardiograms showed no differences among groups regarding LVEF and only slight differences between groups within the normal range. Hs-TnI patients had lower myocardial work and longitudinal strain. The presence of an abnormal echocardiogram was more frequent in the elevated CVB group compared to controls (23.8 vs 10.3%, P = 0.123) but mainly associated with mild abnormalities in deformation parameters. Management did not change in any case and no major cardiovascular events except deep vein thrombosis occurred after a median follow-up of 7 months. CONCLUSION: Minimal abnormalities in cardiac structure and function are observed in COVID19 survivors without previous cardiovascular diseases who presented a significant CVB rise at admission, with no impact on patient management or short-term prognosis. These results do not support a routine screening program after discharge in this population.

Extracorporeal Membrane Oxygenation Retrieval in Coronavirus Disease 2019: A Case-Series of 19 Patients Supported at a High-Volume Extracorporeal Membrane Oxygenation Center.

OBJECTIVE: To evaluate the performance of the extracorporeal membrane oxygenation retrieval team at a high-volume extracorporeal membrane oxygenation center during the coronavirus disease 2019 pandemic. DESIGN: Observational study including all adult patients with confirmed infection due to severe acute respiratory syndrome coronavirus-2 cannulated at other centers and transported on extracorporeal membrane oxygenation to the ICU of the Vall d'Hebron University Hospital between 15 March and 10 June 2020. SETTING: The ICU (capacity expanded to 200 during the pandemic) of the Vall d'Hebron University Hospital (a 1,100-bed public university hospital in Barcelona), the referral center for extracorporeal respiratory support in Catalonia (7.5 million inhabitants). PATIENTS: Extracorporeal membrane oxygenation was considered if the Pao2/Fio2 ratio less than 80 mm Hg (refractory to prone position) and/or Paco2 greater than 80 mm Hg and pH less than 7.25 for more than 6 hours, and no contraindications for extracorporeal support were present. INTERVENTIONS: Venovenous extracorporeal membrane oxygenation was initiated in the primary center. Then, patients were transferred to the ICU of the Vall d'Hebron University Hospital where they received support until respiratory improvement. After decannulation, patients were discharged for rehabilitation at the primary center. MEASUREMENTS AND MAIN RESULTS: Nineteen patients with severe acute respiratory syndrome coronavirus-2 infection and with a mean Pao2/Fio2 ratio of 71 mm Hg (57-118 mm Hg) despite prone positioning and a mean Paco2 of 70 mm Hg (47-110 mm Hg) were transferred to our center from their primary hospital after cannulation and received venovenous extracorporeal membrane oxygenation support. Prior to cannulation, six patients (31.5%) presented vascular thrombosis, and nine (47.4%) were already receiving anticoagulant therapy. Eighteen transfers were carried out with no significant complications. While on extracorporeal membrane oxygenation, thrombotic events were recorded in nine patients (47.4%) and hemorrhagic events in 13 (68.4%). Thirteen patients (68.4%) were successfully weaned, and 12 (63.1%) were discharged home. CONCLUSIONS: Extracorporeal membrane oxygenation retrieval can rescue young, previously healthy patients with severe coronavirus disease 2019 in whom all the conventional respiratory measures have failed. Thrombotic and hemorrhagic complications are frequent in this cohort.

Closed-loop oxygen control improves oxygen therapy in acute hypoxemic respiratory failure patients under high flow nasal oxygen: a randomized cross-over study (the HILOOP study).

BACKGROUND: We aimed to assess the efficacy of a closed-loop oxygen control in critically ill patients with moderate to severe acute hypoxemic respiratory failure (AHRF) treated with high flow nasal oxygen (HFNO). METHODS: In this single-centre, single-blinded, randomized crossover study, adult patients with moderate to severe AHRF who were treated with HFNO (flow rate ≥ 40 L/min with FiO2 ≥ 0.30) were randomly assigned to start with a 4-h period of closed-loop oxygen control or 4-h period of manual oxygen titration, after which each patient was switched to the alternate therapy. The primary outcome was the percentage of time spent in the individualized optimal SpO2 range. RESULTS: Forty-five patients were included. Patients spent more time in the optimal SpO2 range with closed-loop oxygen control compared with manual titrations of oxygen (96.5 [93.5 to 98.9] % vs. 89 [77.4 to 95.9] %; p < 0.0001) (difference estimate, 10.4 (95% confidence interval 5.2 to 17.2). Patients spent less time in the suboptimal range during closed-loop oxygen control, both above and below the cut-offs of the optimal SpO2 range, and less time above the suboptimal range. Fewer number of manual adjustments per hour were needed with closed-loop oxygen control. The number of events of SpO2 < 88% and < 85% were not significantly different between groups. CONCLUSIONS: Closed-loop oxygen control improves oxygen administration in patients with moderate-to-severe AHRF treated with HFNO, increasing the percentage of time in the optimal oxygenation range and decreasing the workload of healthcare personnel. These results are especially relevant in a context of limited oxygen supply and high medical demand, such as the COVID-19 pandemic. Trial registration The HILOOP study was registered at www. CLINICALTRIALS: gov under the identifier NCT04965844 .

To prone or not to prone ARDS patients on ECMO.

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2021. Other selected articles can be found online at  https://www.biomedcentral.com/collections/annualupdate2021 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from  https://link.springer.com/bookseries/8901 .

Hemadsorption as a Treatment Option for Multisystem Inflammatory Syndrome in Children Associated With COVID-19. A Case Report.

Multisystem Inflammatory Syndrome in Children (MIS-C) associated with COVID-19 is characterized by hypercytokinemia leading to overwhelming inflammation. We describe the use of a hemadsorption device as part of the supportive treatment for cytokine storm.