Practices associated with reduced infection risk included prophylaxis with second-generation cephalosporins ( HR : @ ; @ % CI : @ to @ ) , whereas post-operative antibiotic duration > @ h ( HR : @ ; @ % CI : @ to @ ) , stress hyperglycemia ( HR : @ ; @ % CI : @ to @ ) ; intubation time of @ to @ h ( HR : @ ; @ % CI : @ to @ ) ; and ventilation > @ h ( HR : @ ; @ % CI : @ to @ ) were associated with increased risk .