Increased airway mucins after cardiopulmonary bypass associated with postoperative respiratory complications in children.
OBJECTIVE
Airway mucins may play an important role in the mechanism of respiratory complications after cardiopulmonary bypass in infants and children. Our aim was to measure airway mucin levels before and after cardiopulmonary bypass and to determine whether changes in mucin levels were associated with the development of respiratory complications.


METHODS
Airway glycoprotein and mucins (MUC5AC, MUC5B, and MUC2) in serial small-volume airway lavage samples from 39 young children who underwent cardiac operations with cardiopulmonary bypass were measured by slot-blot assay with specific antimucin peptide antibodies. The relationship between mucin changes and post-cardiopulmonary bypass respiratory complications was investigated. Airway lavage samples were also collected from 11 children before and after operation without cardiopulmonary bypass, and changes in mucin levels were compared with those in subjects who underwent cardiopulmonary bypass. Airway lavage sample DNA was also measured to investigate the relationship between mucin changes and lung injury.


RESULTS
Glycoprotein, MUC5AC, and MUC5B levels were significantly increased after cardiopulmonary bypass (P <.001) whereas MUC2 level was not. Children with respiratory complications showed significantly higher glycoprotein and MUC5AC levels than did children without respiratory complications before and after cardiopulmonary bypass (P <.05). Increase of total mucin (MUC5AC, MUC5B, and MUC2) during cardiopulmonary bypass showed positive correlation with DNA increase during cardiopulmonary bypass (r = 0.73), PaCO(2) (r = 0.62) and alveolar-arterial oxygen difference (r = 0.55) immediately after cardiopulmonary bypass. Increase of total mucin was associated with postoperative respiratory complications and their severity. There were no significant changes detected in airway mucin during operations without cardiopulmonary bypass.


CONCLUSIONS
Airway mucins were increased during cardiopulmonary bypass, and this increase was associated with markers of lung injury after cardiopulmonary bypass and with the development of postoperative respiratory complications.
Imura
Hajime
H
Bristol Heart Institute, United Kingdom.
Duncan
Heather P
HP
Corfield
Anthony P
AP
Myerscough
Neil
N
Caputo
Massimo
M
Angelini
Gianni D
GD
Wolf
Andrew R
AR
Henderson
A John
AJ
D015415:Biomarkers / Q000032:analysis; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D002648:Child; D002669:Child Welfare; D002675:Child, Preschool; D006023:Glycoproteins / Q000378:metabolism; D006330:Heart Defects, Congenital / Q000378:metabolism / Q000601:surgery; D006801:Humans; D007223:Infant; D007229:Infant Welfare; D009077:Mucins / Q000145:classification / Q000378:metabolism*; D010100:Oxygen / Q000097:blood; D011183:Postoperative Complications / Q000209:etiology* / Q000378:metabolism*; D011184:Postoperative Period; D012128:Respiratory Distress Syndrome / Q000209:etiology* / Q000378:metabolism*; D020545:Respiratory Mucosa / Q000378:metabolism; D012720:Severity of Illness Index; D013223:Statistics as Topic; D013997:Time Factors; D014132:Trachea / Q000378:metabolism*; D016896:Treatment Outcome; D006113:United Kingdom
D015415:Biomarkers; D006023:Glycoproteins; D009077:Mucins; D010100:Oxygen