Can double-effect reasoning justify lethal organ donation?

The dead donor rule (DDR) prohibits retrieval protocols that would be lethal to the donor. Some argue that compliance with it can be maintained by satisfying the requirements of double-effect reasoning (DER). If successful, one could support organ donation without reference to the definition of death while being faithful to an ethic that prohibits intentionally killing innocent human life. On the contrary, I argue that DER cannot make lethal organ donation compatible with the DDR, because there are plausible ways it fails DER's requirements. A key takeaway is that the theories of intention and proportionality assumed in DER matter for its plausibility as a constraint on practical reasoning.