Which of the following statements about bowel preparation for colon surgery is/are true?

A. Bowel preparation is accomplished by a combination of mechanical cleansing and nonabsorbable antibiotics

C. Commercial electrolyte-polyethylene glycol solutions provide mechanical cleansing without inducing electrolyte imbalance

D. Nonabsorbable antibiotics such as neomycin and erythromycin base are administered the day before the operation in three doses.

DISCUSSION: Bowel preparation is accomplished by a combination of mechanical cleansing and nonabsorbable antibiotics. In the past, 3 days of clear liquids was used as a means of mechanical cleansing; this was neither sufficient nor practical. Presently, an electrolyte-polyethylene glycol solution is commercially available that provides effective mechanical cleansing without inducing electrolyte imbalance. Nonabsorbable antibiotics such as neomycin and erythromycin base are administered the day before the operation, usually at 1 P.M., 2 P.M., and 11 P.M. Intravenous antibiotics are administered within hours of surgery to achieve maximal levels in the tissues during the operation.