Pre-operatively, the patients are assessed in the Preanaesthetic clinic as necessary. Blood tests including CBC and differential, blood type and antibody screen, creatinine and electrolytes are routinely obtained. Urine samples will be sent preoperatively for culture and sensitivity. If the urine culture is positive, organism specific antibiotics will be prescribed prior to treatment. If the urine culture is negative, prophylactic antibiotics will be ordered and administered, prior to the induction of anaesthesia, by the treating surgeon.