Positive end-expiratory pressure titration with electrical impedance tomography and pressure–volume curve in severe acute respiratory distress syndrome

Abstract

BackgroundThe study objective was to compare titration of positive end-expiratory pressure (PEEP) with electrical impedance tomography (EIT) and with ventilator-embedded pressure–volume loop in severe acute respiratory distress syndrome (ARDS).MethodsWe have designed a prospective study with historical control group. Twenty-four severe ARDS patients (arterial oxygen partial pressure to fractional inspired oxygen ratio, PaO2/FiO2 < 100 mmHg) were included in the EIT group and examined prospectively. Data from another 31 severe ARDS patients were evaluated retrospectively (control group). All patients were receiving medical care under identical general support guidelines and protective mechanical ventilation. The PEEP level selected in the EIT group was the intercept point of cumulated collapse and overdistension percentages curves. In the control group, optimal PEEP was selected 2 cmH2O above the lower inflection point on the static pressure–volume curve.ResultsPatients in the EIT group were younger (P < 0.05), and their mean plateau pressure was 1.5 cmH2O higher (P < 0.01). No differences in other baseline parameters such as APACHE II score, PaO2/FiO2, initial PEEP, driving pressure, tidal volume, and respiratory system compliance were found. Two hours after the first PEEP titration, significantly higher PEEP, compliance, and lower driving pressure were found in the EIT group (P < 0.01). Hospital survival rates were 66.7% (16 of 24 patients) in the EIT group and 48.4% (15 of 31) in the control group. Identical rates were found regarding the weaning success rate: 66.7% in the EIT group and 48.4% in the control group.ConclusionIn severe ARDS patients, it was feasible and safe to guide PEEP titration with EIT at the bedside. As compared with pressure–volume curve, the EIT-guided PEEP titration may be associated with improved oxygenation, compliance, driving pressure, and weaning success rate. The findings encourage further randomized control study with a larger sample size and potentially less bias in the baseline data.Trial Registration NCT03112512Electronic supplementary materialThe online version of this article (10.1186/s13613-019-0484-0) contains supplementary material, which is available to authorized users.

Influence of overdistension/recruitment induced by high positive end-expiratory pressure on ventilation–perfusion matching assessed by electrical impedance tomography with saline bolus

“…It remains challenging for physicians to balance the regional recruitment and overdistension induced by PEEP. EIT has been used to assess the effect of PEEP on regional recruitment and overdistension in clinical practice [19][20][21][22][23]. Franchineau et al defined an optimal PEEP would keep regional collapse < 10% with minimum overdistension [20].…”

“…Franchineau et al defined an optimal PEEP would keep regional collapse < 10% with minimum overdistension [ 20 ]. Zhao et al set the PEEP to the cross point of cumulated collapse and overdistension curve [ 22 ]. Both studies calculated collapse and overdistension according to the regional compliance curves along PEEP changes.…”

The use of electrical impedance tomography for individualized ventilation strategy in COVID-19: a case report

“…The protocol for EIT-guided PEEP titration increases pressure starting at 8 cmH 2 O with 2-min steps of 2 cmH 2 O till 20 cmH 2 O, and then decreases it with 2 cmH 2 O steps [ 4 ]. At each step, fractions of regional collapse and overdistention are calculated and the PEEP level selected (12 cmH 2 O) at the intercept point, to provide the best compromise between collapsed and overdistended lung (Fig.…”

Electrical Impedance Tomography for Cardio-Pulmonary Monitoring

“…Mauri et al [50] showed an improved homogeneous ventral-to-dorsal ventilation distribution during assisted ventilation at a high PEEP-level when compared with control mechanical ventilation. Zhao et al [51] compared individualized PEEP levels which were obtained from ODLC measurements to PEEP levels which were derived from global P/V curves (PEEP 2 cmH 2 O above LIP) and demonstrated that EIT-based PEEP titration might improve lung mechanics, gas exchange, and weaning success. ODLC measurements were also used to individually titrate PEEP in ARDS patients during ultra-protective mechanical ventilation (using a V T of 4 mL/kg BW or below) who underwent extra corporeal membrane oxygenation [52].…”