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Published on: June 20, 2015
Changes in intraocular pressure during cardiac surgery with and without cardiopulmonary bypass
Hironobu Hayashi1, Masahiko Kawaguchi, Kyoko Hasuwa
1Department of Anesthesiology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan.
Purpose:
Data on intraocular pressure (IOP) during cardiac surgery with cardiopulmonary bypass (CPB) and anesthetic management are limited. This study was conducted to investigate changes in IOP during cardiac surgery with and without CPB.
Methods:
IOP was intraoperatively measured in patients undergoing elective cardiac surgery with (n = 35) or without (n = 11) CPB. Measurements were performed using a Tonopen(®) XL hand-held tonometer at the following five time points in patients with CPB: (1) 30 min after anesthesia induction (baseline), (2) prior to CPB, (3) 60 min after the beginning of CPB, (4) before cessation of CPB, and (5) at the end of operation; and in patients without CPB: (1) 30 min after anesthesia induction (baseline), (2) prior to anastomosis, (3) during left anterior descending artery anastomosis, (4) during left circumflex or right coronary artery anastomosis (head-down position), and (5) at the end of operation.
Results:
In patients with CPB, IOP values at points 3 and 4 were significantly decreased compared with baseline values and returned to baseline levels at point 5. In patients without CPB, values were significantly increased and peaked at point 4 in the head-down position compared with baseline and prior to anastomosis.
Conclusion:
Results indicate that during cardiac surgery, IOP values decreased during CPB and increased during anastomosis in the head-down position in patients without CPB.
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