Low-frequency ventilation during cardiopulmonary bypass for lung protection: A randomized controlled trial

J Card Surg. 2019 Jun;34(6):385-399. doi: 10.1111/jocs.14044. Epub 2019 May 2.


Objective: Pulmonary dysfunction is a common complication in patients undergoing heart surgery. Current clinical practice does not include any specific strategy for lung protection. To compare the anti-inflammatory effects of low-frequency ventilation (LFV), as measured by nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) p65 pathway activation, for the entire cardiopulmonary bypass (CPB) vs both lungs left collapsed in patients undergoing coronary artery bypass grafting (CABG).

Methods: Two groups parallel randomized controlled trial. The primary outcome was inflammation measured by NF-κB p65 activation in pre- and post-CPB lung biopsies. Secondary outcomes were additional inflammatory markers in both biopsy tissue and blood.

Results: Thirty-seven patients were randomly allocated to LFV (18) and to both lungs left collapsed (19). The mean concentration of NF-κB p65 in the biopsies before chest closure (adjusted for pre-CPB concentration) was higher in the LFV group compared to both lungs left collapsed group but this was not significant (0.102, 95% confidence interval, -0.022 to 0.226, P = 0.104). There were no significant differences between groups in the other inflammatory markers measured in tissue and blood.

Conclusions: In patients undergoing elective CABG, the use of LFV during CPB when compared to both lungs left collapsed does not seem to reduce inflammation in lung biopsies and blood.

Keywords: cardiopulmonary bypass; low-frequency ventilation; lung biopsy; lung protection; nuclear factor κ-light-chain-enhancer of activated B cells.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Biomarkers / metabolism
  • Cardiopulmonary Bypass*
  • Coronary Artery Bypass*
  • Female
  • Humans
  • Inflammation / diagnosis
  • Intraoperative Complications / diagnosis
  • Intraoperative Complications / pathology
  • Intraoperative Complications / prevention & control*
  • Lung / metabolism
  • Lung / pathology
  • Male
  • Middle Aged
  • Pulmonary Atelectasis / diagnosis
  • Pulmonary Atelectasis / pathology
  • Pulmonary Atelectasis / prevention & control*
  • Respiration, Artificial / methods*
  • Transcription Factor RelA / metabolism


  • Biomarkers
  • Transcription Factor RelA