, Volume 189, Issue 6, pp 499–509 | Cite as

Tidal Lung Recruitment and Exhaled Nitric Oxide During Coronary Artery Bypass Grafting in Patients With and Without Chronic Obstructive Pulmonary Disease

  • Alysson R. Carvalho
  • Fumito Ichinose
  • Ivany A. Schettino
  • Dean Hess
  • Javier Rojas
  • Antonio Giannella-Neto
  • Arvind Agnihotri
  • Jennifer Walker
  • Thomas E. MacGillivray
  • Marcos F. Vidal Melo



We studied the occurrence of intraoperative tidal alveolar recruitment/derecruitment, exhaled nitric oxide (eNO), and lung dysfunction in patients with and without chronic obstructive pulmonary disease (COPD) undergoing coronary artery bypass grafting (CABG).


We performed a prospective observational physiological study at a university hospital. Respiratory mechanics, shunt, and eNO were assessed in moderate COPD patients undergoing on-pump (n = 12) and off-pump (n = 8) CABG and on-pump controls (n = 8) before sternotomy (baseline), after sternotomy and before cardiopulmonary bypass (CPB), and following CPB before and after chest closure. Respiratory system resistance (R rs), elastance (E rs), and stress index (to quantify tidal recruitment) were estimated using regression analysis. eNO was measured with chemiluminescence.


Mechanical evidence of tidal recruitment/derecruitment (stress index <1.0) was observed in all patients, with stress index <0.8 in 29% of measurements. Rrs in on-pump COPD was larger than in controls (p < 0.05). Ers increased in controls from baseline to end of surgery (19.4 ± 5.5 to 27.0 ± 8.5 ml cm H2O−1, p < 0.01), associated with increased shunt (p < 0.05). Neither Ers nor shunt increased significantly in the COPD on-pump group. eNO was comparable in the control (11.7 ± 7.0 ppb) and COPD on-pump (9.9 ± 6.8 ppb) groups at baseline, and decreased similarly by 29% at end of surgery(p < 0.05). Changes in eNO were not correlated to changes in lung function.


Tidal recruitment/derecruitment occurs frequently during CABG and represents a risk for ventilator-associated lung injury. eNO changes are consistent with small airway injury, including that from tidal recruitment injury. However, those changes are not correlated with respiratory dysfunction. Controls have higher susceptibility to develop complete lung derecruitment.


Acute lung injury Pulmonary disease Chronic obstructive Coronary artery bypass surgery Nitric oxide Perioperative period 



The authors acknowledge Dr. Hui Zheng for reviewing the statistical analysis, and RNs Michelle Curran Cereno, Laura Collier, Cindy Cooney, Rosemary Daggett, Adrianne Diamond, Valerie Buckley, Danielle Faldetta, Barbara Hill, Jennifer Mills, Karen Parmenter, Joann Pellegrino, Valery Petit-Ton, Christine Tetrault Angelini, Sharon Zisk who helped with the intraoperative measurements and blood samples.

Conflict of interest

There is no conflict of interest.


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Alysson R. Carvalho
    • 1
  • Fumito Ichinose
    • 2
  • Ivany A. Schettino
    • 2
  • Dean Hess
    • 2
  • Javier Rojas
    • 2
  • Antonio Giannella-Neto
    • 4
  • Arvind Agnihotri
    • 3
  • Jennifer Walker
    • 3
  • Thomas E. MacGillivray
    • 3
  • Marcos F. Vidal Melo
    • 2
  1. 1.Laboratory of Respiration PhysiologyCarlos Chagas Filho Institute of BiophysicsRio de JaneiroBrazil
  2. 2.Department of Anesthesia, Critical Care, and Pain MedicineMassachusetts General Hospital, Harvard Medical SchoolBostonUSA
  3. 3.Department of SurgeryMassachusetts General Hospital, Harvard Medical SchoolBostonUSA
  4. 4.Biomedical Engineering ProgramFederal University of Rio de JaneiroRio de JaneiroBrazil

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