Antibiotic Abdominal Lavage in Colorectal Surgery

The purpose of the study was to evaluate the effects of peritoneal lavage with normal saline or an antibiotic solution (clindamycin-gentamicin) on intra-abdominal abscesses and wound infection and to determine the microbiologic impact of both irrigations on peritoneal contamination.  

An open surgical approach was used in all patients. The patients were randomized by means of an Internet randomization module into two groups: those undergoing an intra-abdominal lavage with normal saline (group 1) and those first undergoing an intra-abdominal lavage with normal saline followed by a second lavage with a clindamycin-gentamicin solution (group 2). Perioperative systemic antibiotics (ciprofloxacin 400 mg and metronidazole 1,500 mg; single-dose preoperatively, within 30 minutes of incision, and re-dosed after four hours when the surgery is prolonged over that time) were used in both groups. No mechanical bowel preparation took place in any patient.

• The study had 103 total patients (51 patients in group 1, 52 patients in group 2).  
• The mean age in group 1 was 68.5 years (SD = 10.2). The mean age in group 2 was 69.9 years (SD = 11.5).
• For group 1, 62% of participants were male and 38% were female. For group 2, 60% of participants were male and 40% were female.
• All patients had a diagnosis of adenocarcinoma.
• Comorbidities included diabetes mellitus (32% of participants in group 1, 29% of participants in group 2), hypertension (48% of participants in group 1, 50% of participants in group 2), dyslipidemia (32% of participants in group 1, 36% of participants in group 2), and cardiomyopathy (24% of participants in group 1, 20% of participants in group 2).
   

A single-site inpatient setting (the coloproctology unit of the General University Hospital of Elche)
 

 Active treatment

Prospective, randomized, placebo-controlled study

• Wound infection was measured by the presence of purulent discharge from the surgical wound, confirmed by microbiologic culture, and determined by a wound treatment nurse blinded to the treatment groups.    
• Intra-abdominal abscess was defined as the presence of a fluid collection on computed tomography (CT) scan in a symptomatic patient, presenting with fever, abdominal pain, prolonged postoperative ileus, or septic stratus. Determined by a radiologist blinded to treatment groups.
   

Wound infection rates were 14% in group 1 and 4% in group 2 (p = 0.009). Intra-abdominal abscess rates were 6% in group 1 and 0% in group 2 (p = 0.014).

In this study, antibiotic lavage was shown to be very effective, reducing the rate of positive culture by 59% after saline lavage to 4% after antibiotic lavage. These data show that, if the peritoneal cavity remains sterile, there is a lower risk of bacteria migrating from the abdominal cavity through the fascia to the subcutaneous tissue. The study also showed reduced intra-abdominal abscess rates.

A lower incidence of infection was noted in patients with antibiotic lavage during contaminated bowel surgery.

Findings would not be generalizable to other groups of patients.

Findings suggest that antibiotic intra-abdominal lavage may reduce surgical infectious complications in patients undergoing bowel surgery.