High oxygen concentration exacerbates cardiopulmonary bypass-induced lung injury.
OBJECTIVE
To investigate the effect of ventilation with 100% oxygen on lung injury associated with surgery involving cardiopulmonary bypass (CPB).


METHODS
A prospective randomized study.


METHODS
University hospital.


METHODS
Thirty patients undergoing coronary artery bypass graft surgery with CPB.


METHODS
Patients were randomized to receive 100% oxygen (Oxygen group) or 50% oxygen (Air group) throughout surgery. During CPB, patients' lungs in the Air group were flushed with air and in the Oxygen group with 100% oxygen.


RESULTS
Lung injury was evaluated by arterial oxygen tension-inspired oxygen concentration (PaO2-FIO2) ratio and cytokine levels (tumor necrosis factor-alpha and interleukin-8) in blood and bronchoalveolar lavage fluid measured before and after CPB. The lowest PaO2-FIO2 value was observed after 40 minutes following the completion of CPB in both groups. PaO2-FIO2 values 6 hours after CPB were not different from baseline in the Air group but remained lower (359+/-63 mmHg and 298+/-78 mmHg; p = 0.013) in the Oxygen group. Blood cytokine levels rose during surgery in both groups. Bronchoalveolar lavage levels of interleukin-8 did not change, whereas tumor necrosis factor-alpha increased only in the Oxygen group (p = 0.035).


CONCLUSIONS
A significant decrease of oxygenation was observed in the early post-CPB period in both groups of patients, with delay in recovery in patients treated with 100% oxygen. A larger increase of the proinflammatory cytokines was found in patients treated with 100% oxygen. High oxygen concentrations during surgery with CPB should be used only when specifically required.
Pizov
R
R
Department of Anesthesiology and CCM, Hadassah Medical Center, Jerusalem, Israel.
Weiss
Y G
YG
Oppenheim-Eden
A
A
Glickman
H
H
Goodman
S
S
Koganov
Y
Y
Barak
V
V
Merin
G
G
Kramer
M R
MR
D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis; D010100:Oxygen / Q000633:toxicity*; D011446:Prospective Studies; D012128:Respiratory Distress Syndrome / Q000209:etiology*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D016209:Interleukin-8; D014409:Tumor Necrosis Factor-alpha; D010100:Oxygen