Ampicillin prophylaxis is given in -

• Prophylactic antibiotics in biliary surgery are designed to reduce the incidence of postoperative wound infections. • The efficacy of antibiotics in the prevention of wound infections has been demonstrated with first, second and third generation cephalosporins, ampicillin associated with clavulanate, ureido-penicillins, aminoglycosides, sulfonamides and quinolones.