Impact of Arterial Cannulation Site on Vasopressor Requirement in Cardiac Surgery

Choice of arterial cannulation site during cardiac surgery is controversial. Some physicians in our institution prefer radial artery site, others prefer aortic site (via femoral artery or brachial artery). The investigators aim to compare these two strategies for vasopressor requirement. The study hypothesis is that radial artery cannulation is associated with a larger dose of vasopressor due aortic to radial arterial pressure gradient phenomenon.