<prompt> Regarding antibiotics true areNo prophylaxis for clean contaminated surgeryNo prophylaxis for gastric ulcer surgeryProphylaxis for colorectal surgeryLocal irrigation with antibiotic contraindicated when systemic antibiotics given  <response>: In clean contaminated surgeries ex : gastric , Prophylactic antibiotics are used In contaminated surgeries , lke colorectal surgeries prophylactic antibiotics are used 