Which of these is true of pre-operative preparation for hysterectomy?

Prophylactic antibiotic: single dose 30 to 60 minutes before skin incision (and not at the time of incision) Cefazolin 1 to 2 g and increased to 3 g for obese patients is recommended. Re-dosing is recommended after 3 hours of surgery and with excessive bleeding. Chlorhexidine-alcohol-based skin preparations have a lower odds of surgical site infection compared with povidone-iodine preparations. Concentrations of 4% or less can be used in the vagina Although treating all patients with bacterial vaginosis may decrease vaginal cuff cellulitis, universal screening preoperatively is not recommended as a routine.