PEEP-FiO2 table versus EIT to titrate PEEP in mechanically ventilated patients with COVID-19-related ARDS.

RATIONALE: It is unknown how to titrate positive end-expiratory pressure (PEEP) in patients with COVID-19-related acute respiratory distress syndrome (ARDS). Guidelines recommend the one-size-fits-all PEEP-FiO2 table. In this retrospective cohort study, an electrical impedance tomography (EIT)-guided PEEP trial was used to titrate PEEP. OBJECTIVES: To compare baseline PEEP according to the high PEEP-FiO2 table and personalized PEEP following an EIT-guided PEEP trial. METHODS: We performed an EIT-guided decremental PEEP trial in patients with moderate-to-severe COVID-19-related ARDS upon intensive care unit admission. PEEP was set at the lowest PEEP above the intersection of curves representing relative alveolar overdistention and collapse. Baseline PEEP was compared with PEEP set according to EIT. We identified patients in whom the EIT-guided PEEP trial resulted in a decrease or increase in PEEP of ≥ 2 cmH2O. MEASUREMENTS AND MAIN RESULTS: We performed a PEEP trial in 75 patients. In 23 (31%) patients, PEEP was decreased ≥ 2 cmH2O, and in 24 (32%) patients, PEEP was increased ≥ 2 cmH2O. Patients in whom PEEP was decreased had improved respiratory mechanics and more overdistention in the non-dependent lung region at higher PEEP levels. These patients also had a lower BMI, longer time between onset of symptoms and intubation, and higher incidence of pulmonary embolism. Oxygenation improved in patients in whom PEEP was increased. CONCLUSIONS: An EIT-guided PEEP trial resulted in a relevant change in PEEP in 63% of patients. These results support the hypothesis that PEEP should be personalized in patients with ARDS.

Advanced respiratory monitoring in mechanically ventilated patients with coronavirus disease 2019-associated acute respiratory distress syndrome.

PURPOSE OF REVIEW: To summarize the current knowledge about the application of advanced monitoring techniques in coronavirus disease 2019 (COVID-19). RECENT FINDINGS: Due to the heterogeneity between patients, management of COVID-19 requires daily monitoring of and/or aeration and inspiratory effort. Electrical impedance tomography can be used to optimize positive end-expiratory pressure, monitor the response to changes in treatment or body position and assess pulmonary perfusion and ventilation/perfusion matching. Lung ultrasound is more readily available and can be used to measure and monitor recruitment, provide an indication of diaphragm function and pulmonary perfusion disturbances. Esophageal pressure measurements enable the calculation of the transpulmonary pressure and inspiratory effort in order to prevent excessive stress on the lung. While esophageal pressure measurements are the golden standard in determining inspiratory effort, alternatives like P0.1, negative pressure swing during a single airway occlusion and change in central venous pressure are more readily available and capable of diagnosing extreme inspiratory efforts. SUMMARY: Although there is little data on the effectiveness of advanced monitoring techniques in COVID-19, regular monitoring should be a central part of the management of COVID-19-related acute respiratory distress syndrome (C-ARDS).