A Cochrane review ¹ included 47 studies with a total of 17,039 subjects. 23 of the studies (n=14,367) included participants undergoing non-cardiac surgery. Overall, α-2 adrenergic (clonidine, dexmedetomidine, or mivazerol) agonists led to a similar risk of all-cause mortality compared with placebo and inactive control. Additionally, the risk of cardiac mortality and myocardial infarction was similar between treatment groups. There was no associated effect on the risk of stroke. Conversely, α-2 adrenergic agonists probably increase the risks of clinically significant bradycardia and hypotension.

SOF table in Cochrane database (licence required) https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD004126.pub3/fu...