What are the plasma half-lives of piperacillin and tazobactam in healthy subjects receiving piperacillin + tazobactam?

In healthy subjects receiving single or multiple doses of piperacillin + tazobactam, the plasma half-lives of both piperacillin and tazobactam ranged from 0.7 to 1.2 hours, unaffected by dose or infusion duration.