Invasive Mechanical Ventilation in COVID-19

Patients with severe COVID-19 pneumonia present with severe hypoxemic respiratory failure, typically meet the clinical criteria for acute respiratory distress syndrome (ARDS) and often require invasive mechanical ventilation. While peculiar pathophysiological aspects deserve discussion to better tailor the mechanical ventilation settings in these patients, most recommendations on the ventilatory management of these patients are derived from studies in patients with ARDS from causes other than COVID-19. Protective ventilation is recommended in most COVID-19 patients, tidal volume should be kept around 6 mL per kg of predicted body weight, positive end-expiratory pressure (PEEP) should be titrated individually considering that in many patients with COVID-19 improvement of oxygenation at higher PEEP is often accompanied by worsening of respiratory system compliance. Therefore, attention should be paid in limiting plateau and driving pressures to avoid excessive strain potentially resulting in ventilator-induced lung injury. Prone positioning has been used extensively in COVID-19 patients, but its impact on mortality is uncertain. Inhaled nitric oxide, extracorporeal CO2 removal (ECCO2R), and extracorporeal membrane oxygenation (ECMO) should be considered in selected patients as rescue measures. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.

Extracorporeal carbon dioxide removal with the Advanced Organ Support system in critically ill COVID-19 patients.

Disturbed oxygenation is foremost the leading clinical presentation in COVID-19 patients. However, a small proportion also develop carbon dioxide removal problems. The Advanced Organ Support (ADVOS) therapy (ADVITOS GmbH, Munich, Germany) uses a less invasive approach by combining extracorporeal CO2 -removal and multiple organ support for the liver and the kidneys in a single hemodialysis device. The aim of our study is to evaluate the ADVOS system as treatment option in-COVID-19 patients with multi-organ failure and carbon dioxide removal problems. COVID-19 patients suffering from severe respiratory insufficiency, receiving at least two treatments with the ADVOS multi system (ADVITOS GmbH, Munich, Germany), were eligible for study inclusion. Briefly, these included patients with acute kidney injury (AKI) according to KDIGO guidelines, and moderate or severe ARDS according to the Berlin definition, who were on invasive mechanical ventilation for more than 72 hours. In total, nine COVID-19 patients (137 ADVOS treatment sessions with a median of 10 treatments per patient) with moderate to severe ARDS and carbon dioxide removal problems were analyzed. During the ADVOS treatments, a rapid correction of acid-base balance and a continuous CO2 removal could be observed. We observed a median continuous CO2 removal of 49.2 mL/min (IQR: 26.9-72.3 mL/min) with some treatments achieving up to 160 mL/min. The CO2 removal significantly correlated with blood flow (Pearson 0.421; P < .001), PaCO2 (0.341, P < .001) and HCO 3 - levels (0.568, P < .001) at the start of the treatment. The continuous treatment led to a significant reduction in PaCO2 from baseline to the last ADVOS treatment. In conclusion, it was feasible to remove CO2 using the ADVOS system in our cohort of COVID-19 patients with acute respiratory distress syndrome and multiorgan failure. This efficient removal of CO2 was achieved at blood flows up to 300 mL/min using a conventional hemodialysis catheter and without a membrane lung or a gas phase.

Ten golden rules for individualized mechanical ventilation in acute respiratory distress syndrome.

Considerable progress has been made over the last decades in the management of acute respiratory distress syndrome (ARDS). Mechanical ventilation(MV) remains the cornerstone of supportive therapy for ARDS. Lung-protective MV minimizes the risk of ventilator-induced lung injury (VILI) and improves survival. Several parameters contribute to the risk of VILI and require careful setting including tidal volume (VT), plateau pressure (Pplat), driving pressure (ΔP), positive end-expiratory pressure (PEEP), and respiratory rate. Measurement of energy and mechanical power allows quantification of the relative contributions of various parameters (VT, Pplat, ΔP, PEEP, respiratory rate, and airflow) for the individualization of MV settings. The use of neuromuscular blocking agents mainly in cases of severe ARDS can improve oxygenation and reduce asynchrony, although they are not known to confer a survival benefit. Rescue respiratory therapies such as prone positioning, inhaled nitric oxide, and extracorporeal support techniques may be adopted in specific situations. Furthermore, respiratory weaning protocols should also be considered. Based on a review of recent clinical trials, we present 10 golden rules for individualized MV in ARDS management.