Clinical value of electrical impedance tomography (EIT) in the management of patients with acute respiratory failure: a single centre experience

Abstract

Objective. We will describe our clinical experience using electrical impedance tomography (EIT) in the management of mechanical ventilation in patients with acute respiratory failure and to determine to which extent EIT-guided positive end-expiratory pressure (PEEP) setting differed from clinically set values. Approach. We conducted a retrospective, observational cohort study performed in a hub centre for the treatment of acute respiratory failure and veno-venous extracorporeal membrane oxygenation (ECMO). Main results. Between January 2017 and December 2019, EIT was performed 54 times in 41 patients, not feasible only in one case because of signal instability. More than 50% was on veno-venous ECMO support. In 16 cases (30%), EIT was used for monitoring mechanical ventilation, i.e. to evaluate recruitability or sigh setting. In 37 cases (70%), EIT was used to set PEEP both with incremental (11 cases in nine patients) and decremental (26 cases, 18 patients) PEEP trial. Clinical PEEP before the decremental PEEP trial (PEEPPRE) was 14.1 ± 3.4 cmH2O and clinical PEEP set by clinicians after the PEEP trial (PEEPPOST) was 13.6 ± 3.1 (p = ns). EIT analyses demonstrated that more hypoxic patients were higher derecruited when compared to less hypoxic patients that were, on the contrary, more overdistended (p < 0.05). No acute effects of PEEP adjustment based on EIT on respiratory mechanics or regional EIT parameters modification were observed. Significance. The variability of EIT findings in our population confirmed the need to provide ventilation settings individually tailored and EIT was confirmed to be an optimal useful clinical bedside noninvasive tool to provide real-time monitoring of the PEEP effect and ventilation distribution.

Bedside Selection of Positive End Expiratory Pressure by Electrical Impedance Tomography in Patients Undergoing Veno-Venous Extracorporeal Membrane Oxygenation Support: A Comparison between COVID-19 ARDS and ARDS from Other Etiologies

“…Data of patients with C-ARDS were collected as part of the STORM study (Spallanzani Institute approval number 84/2020; NCT04424992), which did not include the present evaluation as a pre-specified endpoint. Data obtained in patients with NC-ARDS for a recent retrospective study were used for comparison [ 19 ]. Informed consent was waived.…”

“…Data of 12 patients with NC-ARDS on ECMO support were retrieved (as a subset of the original 41 patients) from the database of our previous study [ 19 ], which included all patients who underwent a clinical EIT-guided PEEP trial in our general ICU from January 2017 to December 2019. For the C-ARDS population, we included all adult patients with ARDS who were mechanically ventilated under ECMO support with a confirmed diagnosis of COVID-19 admitted to our 10-bed ICU between January 2021 and May 2021 and who underwent an EIT examination to set PEEP.…”

“…According to our clinical practice, we approached PEEP setting with a decremental PEEP trial, starting from a PEEP level 2 to 4 cm H 2 O above the pre-existing PEEP level. As previously described [ 19 ], the decremental PEEP trial was preceded by a recruitment manoeuvre (35 cm H 2 O for 30 s), followed by 2 cm H 2 O decremental steps lasting 10 min each. At each PEEP level, mechanical respiratory parameters and regional EIT data (i.e., tidal volume distribution in the ventral to dorsal regions of interest) were recorded.…”

“…In our intensive care unit (ICU), EIT has been widely used for research purposes [ 13 , 14 , 15 , 16 , 17 , 18 ]. A recent paper described our clinical experience using EIT to individualize and optimize ventilation management in patients with critical NC-ARDS (with or without ECMO) [ 19 ]. More recently, during the outbreak of SARS-CoV-2-related respiratory failure, the use of EIT to set PEEP was routinely implemented [ 9 , 10 ].…”

Spatial Ventilation Inhomogeneity Determined by Electrical Impedance Tomography in Patients With Chronic Obstructive Lung Disease

“…The number of clinical studies studying the performance of EIT in identifying airway obstruction in patients suffering from COPD is still rather limited. In contrast to the relatively broad interest in EIT applications in mechanically ventilated patients ( Kobylianskii et al, 2016 ; Frerichs et al, 2017 ; Zhao et al, 2020b ; Bronco et al, 2021 ), there exists only a handful of research groups investigating the use of EIT in spontaneously breathing patients with COPD. Hence, the general data availability from this patient group is low and many aspects of data acquisition, analysis, and interpretation are not clarified yet.…”