The purpose of this study is to determine the tissue kinetics of ertapenem in colonic tissue from three hours up to six hours (25% of dosing interval) after administration of ertapenem.

The purpose of this study is to determine the tissue kinetics of ertapenem in colorectal tissue from three hours up to six hours (25% of dosing interval) after administration of ertapenem before an elective surgical intervention (open or laparoscopic surgery) at the colon/rectum. Subjects are patients. Hospitalized patients 18 years or older requiring elective surgical intervention (open or laparoscopic surgery) at the colon will be eligible for this study.

Inclusion Criteria:

• Hospitalized patients 18 years or older requiring elective surgical intervention (open or laparoscopic surgery) at the colon will be eligible for this study.
• Patients with benignant disorders (e.g. colonic diverticulosis) will be preferred.

Exclusion Criteria:

• Pregnancy or lactation in women
• Emergency surgery, history of serious allergy or intolerance to β-lactam antibiotics and other carbapenems
• Systemic antimicrobial therapy with ceftazidime (internal standard of high-performance liquid chromatography / mass spectrometry) within a 7 days period prior to study entry
• Ongoing intraabdominal infections
• Terminal illness
• Chronic immunosuppressive therapy
• Severe diseases of the liver, e.g. cirrhosis of the liver with ALT or AST > 6 x upper limit of normal (ULN) and bilirubin > 3 x ULN, severe renal insufficiency with a creatinine clearance ≤30 mL/min., neutrophil count < 1000 cells/mm3, platelets < 75000 cells/mm3 and coagulation studies (INR) > 1.5 x ULN, ongoing therapy with valproin acid.