Dataset Information

Effects of PEEP on regional ventilation-perfusion mismatch in the acute respiratory distress syndrome.

ABSTRACT:

Purpose

In the acute respiratory distress syndrome (ARDS), decreasing Ventilation-Perfusion [Formula: see text] mismatch might enhance lung protection. We investigated the regional effects of higher Positive End Expiratory Pressure (PEEP) on [Formula: see text] mismatch and their correlation with recruitability. We aimed to verify whether PEEP improves regional [Formula: see text] mismatch, and to study the underlying mechanisms.

Methods

In fifteen patients with moderate and severe ARDS, two PEEP levels (5 and 15 cmH₂O) were applied in random order. [Formula: see text] mismatch was assessed by Electrical Impedance Tomography at each PEEP. Percentage of ventilation and perfusion reaching different ranges of [Formula: see text] ratios were analyzed in 3 gravitational lung regions, leading to precise assessment of their distribution throughout different [Formula: see text] mismatch compartments. Recruitability between the two PEEP levels was measured by the recruitment-to-inflation ratio method.

Results

In the non-dependent region, at higher PEEP, ventilation reaching the normal [Formula: see text] compartment (p = 0.018) increased, while it decreased in the high [Formula: see text] one (p = 0.023). In the middle region, at PEEP 15 cmH₂O, ventilation and perfusion to the low [Formula: see text] compartment decreased (p = 0.006 and p = 0.011) and perfusion to normal [Formula: see text] increased (p = 0.003). In the dependent lung, the percentage of blood flowing through the non-ventilated compartment decreased (p = 0.041). Regional [Formula: see text] mismatch improvement was correlated to lung recruitability and changes in regional tidal volume.

Conclusions

In patients with ARDS, higher PEEP optimizes the distribution of both ventilation (in the non-dependent areas) and perfusion (in the middle and dependent lung). Bedside measure of recruitability is associated with improved [Formula: see text] mismatch.

SUBMITTER: Pavlovsky B

PROVIDER: S-EPMC9272883 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Effects of PEEP on regional ventilation-perfusion mismatch in the acute respiratory distress syndrome.

Pavlovsky Bertrand B Pesenti Antonio A Spinelli Elena E Scaramuzzo Gaetano G Marongiu Ines I Tagliabue Paola P Spadaro Savino S Grasselli Giacomo G Mercat Alain A Mauri Tommaso T

Critical care (London, England) 20220711 1

<h4>Purpose</h4>In the acute respiratory distress syndrome (ARDS), decreasing Ventilation-Perfusion [Formula: see text] mismatch might enhance lung protection. We investigated the regional effects of higher Positive End Expiratory Pressure (PEEP) on [Formula: see text] mismatch and their correlation with recruitability. We aimed to verify whether PEEP improves regional [Formula: see text] mismatch, and to study the underlying mechanisms.<h4>Methods</h4>In fifteen patients with moderate and sever ...[more]

PMID: 35818077

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Dataset Information

Effects of PEEP on regional ventilation-perfusion mismatch in the acute respiratory distress syndrome.

Purpose

Methods

Results

Conclusions

Publications

Effects of PEEP on regional ventilation-perfusion mismatch in the acute respiratory distress syndrome.

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