I think if you're going to circ you'd better opt for as high a dose of Vit K as you can get -- you're already putting your LO at risk by circumcising; I wouldn't compound the risk by trying to guess at an oral Vit K dosage. In fact, I'd be surprised if any ped would agree to do a circumcision on a baby who has not received a Vit K injection.
I would guess that the oral Vit. K. is intended as a "just in case" supplement for babies who have no complications, bruising, etc. during birth, and is certainly NOT intended for babies who are going under the knife within a few hours of birth.
Please, for the sake of your little one's health and safety -- I would gently encourage you to visit the Case Against Circumcision forum and read some of the resources and links there, and reconsider your decision to circ. It is a medically unnecessary procedure, has all the risks of any elective surgery, and will permanently disfigure your baby. IMO, there is no reason strong enough to argue for it.
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