Wounds are classified according to the likelihood of bacterial contamination. Which of the following statement(s) is/are true concerning wound classifications?

a. A clean-contaminated wound would be that associated with an elective colon resection with adequate mechanical and antibiotic bowel preparation

b. A contaminated wound would include a resection of obstructed bowel with gross spillage of intestinal contents 

c. In a clean wound, no viscus is entered

d. Antibiotic prophylaxis should be administered for all clean-contaminated and contaminated wounds and selectively in patients involving a clean wound

Wounds are classified under three classes according to the likelihood of bacterial contamination: 1) clean (no viscus is entered; e.g., herniorrhaphy); 2) clean-contaminated (minimal contamination; e.g., elective colon resection with adequate mechanical and antibiotic bowel preparation, and 3) contaminated (heavily contaminated surgery; e.g., resection of unprepared, obstructed bowel with gross spillage of intestinal contents or stool, drainage of abscesses, debridement of traumatic neglected wounds). Antibiotic prophylaxis generally should be administered for class 2 and 3 types of wounds, but patients undergoing clean surgery do not always require antimicrobial antibiotic prophylaxis. An exception to this tenet involves cases in which a prosthetic material may be used (artificial joint, heart valve, tissue patch).