Adaptive Support Ventilation and Lung-Protective Ventilation in ARDS

Elias N Baedorf Kassis; Andres Brenes Bastos; Maximillian S Schaefer; Krystal Capers; Benjamin Hoenig; Valerie Banner-Goodspeed; Daniel Talmor

doi:10.4187/respcare.10159

Adaptive Support Ventilation and Lung-Protective Ventilation in ARDS

Respir Care. 2022 Dec;67(12):1542-1550. doi: 10.4187/respcare.10159. Epub 2022 Aug 16.

Authors

Elias N Baedorf Kassis¹, Andres Brenes Bastos², Maximillian S Schaefer³, Krystal Capers³, Benjamin Hoenig⁴, Valerie Banner-Goodspeed³, Daniel Talmor³

Affiliations

¹ Division of Pulmonary, Critical Care and Sleep Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; and Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts. enbaedor@bidmc.harvard.edu.
² Department of Anesthesia, Yale School of Medicine, New Haven, Connecticut.
³ Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
⁴ Albany Medical College, Albany, New York.

PMID: 35973716
DOI: 10.4187/respcare.10159

Abstract

Background: Adaptive support ventilation (ASV) is a partially closed-loop ventilation mode that adjusts tidal volume (V_T) and breathing frequency (f) to minimize mechanical work and driving pressure. ASV is routinely used but has not been widely studied in ARDS.

Methods: The study was a crossover study with randomization to intervention comparing a pressure-regulated, volume-targeted ventilation mode (adaptive pressure ventilation [APV], standard of care at Beth Israel Deaconess Medical Center) set to V_T 6 mL/kg in comparison with ASV mode where V_T adjustment is automated. Subjects received standard of care (APV) or ASV and then crossed over to the alternate mode, maintaining consistent minute ventilation with 1-2 h in each mode. The primary outcome was V_T corrected for ideal body weight (IBW) before and after crossover. Secondary outcomes included driving pressure, mechanics, gas exchange, mechanical power, and other parameters measured after crossover and longitudinally.

Results: Twenty subjects with ARDS were consented, with 17 randomized and completing the study (median P_aO₂ /F_IO₂ 146.6 [128.3-204.8] mm Hg) and were mostly passive without spontaneous breathing. ASV mode produced marginally larger V_T corrected for IBW (6.3 [5.9-7.0] mL/kg IBW vs 6.04 [6.0-6.1] mL/kg IBW, P = .035). Frequency was lower with patients in ASV mode (25 [22-26] breaths/min vs 27 [22-30)] breaths/min, P = .01). In ASV, lower respiratory-system compliance correlated with smaller delivered V_T/IBW (R² = 0.4936, P = .002). Plateau (24.7 [22.6-27.6] cm H₂O vs 25.3 [23.5-26.8] cm H₂O, P = .14) and driving pressures (12.8 [9.0-15.8] cm H₂O vs 11.7 [10.7-15.1] cm H₂O, P = .29) were comparable between conventional ventilation and ASV. No adverse events were noted in either ASV or conventional group related to mode of ventilation.

Conclusions: ASV targeted similar settings as standard of care consistent with lung-protective ventilation strategies in mostly passive subjects with ARDS. ASV delivered V_T based upon respiratory mechanics, with lower V_T and mechanical power in subjects with stiffer lungs.

Keywords: ARDS; ASV; driving pressure; esophageal balloon; lung-protective ventilation; mechanical ventilation; transpulmonary pressure.

Publication types

Randomized Controlled Trial

MeSH terms

Cross-Over Studies
Humans
Lung
Respiration, Artificial*
Respiratory Distress Syndrome* / therapy
Tidal Volume