TY - JOUR
T1 - Tidal lung recruitment and exhaled nitric oxide during coronary artery bypass grafting in patients with and without chronic obstructive pulmonary disease
AU - Carvalho, Alysson R.
AU - Ichinose, Fumito
AU - Schettino, Ivany A.
AU - Hess, Dean
AU - Rojas, Javier
AU - Giannella-Neto, Antonio
AU - Agnihotri, Arvind
AU - Walker, Jennifer
AU - MacGillivray, Thomas E.
AU - Vidal Melo, Marcos F.
PY - 2011/12
Y1 - 2011/12
N2 - Background: 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). Methods: 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. Results: 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 H 2O -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. Conclusions: 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.
AB - Background: 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). Methods: 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. Results: 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 H 2O -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. Conclusions: 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.
KW - Acute lung injury
KW - Chronic obstructive
KW - Coronary artery bypass surgery
KW - Nitric oxide
KW - Perioperative period
KW - Pulmonary disease
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U2 - 10.1007/s00408-011-9325-0
DO - 10.1007/s00408-011-9325-0
M3 - Article
C2 - 21952833
AN - SCOPUS:83555173680
SN - 0341-2040
VL - 189
SP - 499
EP - 509
JO - Lung
JF - Lung
IS - 6
ER -