Penetration of a prophylactic antibiotic into peritoneal fluid

Preventing pancreatic infection in acute pancreatitis

In acute pancreatitis, pancreatic inflammation may be complicated by the development of pancreatic infection with a high associated mortality. Pancreatic infection is related to the extent of pancreatic inflammation and necrosis and typically occurs in the second or third week of severe disease. It may be associated with a wide range of Gram-positive and Gram-negative bacteria, notably enterobacteria and also with Candida spp. Current surgical practice in the UK is to use prophylactic antimicrobial therapy in patients with severe disease, with the aim of preventing secondary pancreatic infection. Experimental evidence demonstrates that prophylactic antibacterial therapy prevents pancreatic infection and reduces mortality. Furthermore, studies of antibacterial prophylaxis in patients with acute pancreatitis suggest that prophylactic antibacterial therapy is associated with a reduction in mortality, particularly in those with severe disease. In general, broad-spectrum antibiotics have been used in animal and human studies. However, current evidence does not allow comparisons to be made between different antimicrobial agents. Nutritional strategies may also be important in the prevention of pancreatic infection. Enteral, rather than parenteral, nutrition has been associated with an improved clinical outcome in severe pancreatitis.

Efficacy of metronidazole lavage in treatment of intraperitoneal sepsis. A prospective study

In a prospective study, 182 consecutive patients were included for the treatment of intraabdominal sepsis with adjuvant metronidazole lavage that was carried out at the end of the operative procedures. Eighty of them underwent emergency surgery for peritonitis and 102 elective surgery for a variety of lesions. Although fecal peritonitis was found in 23 and malignant tumors in 84 patients, there was not a single instance of intraabdominal abscess in 182 patients, but the incidence of wound infection was 2.66% in the emergency group and 0% in the elective group; mortality was 5% and 3.9%, respectively. Therefore, adjuvant metronidazole lavage provides confidence in the treatment of intraperitoneal abscess, and it enhances a quick recovery. It is safe to use and cost effective.

Pre-, intra-, and postoperative antibiotics

Endogenous contamination from perforation or rupture of the gastrointestinal tract; exogenous contamination from missiles, knives, or invasive lines and tubes; and immunodepression related to the severity of injury are responsible for the increased infectious complications noted in patients who have undergone laparotomy for abdominal trauma. Perioperative use of clindamycin and an aminoglycoside, a second- or third-generation cephalosporin, or an enhanced-spectrum penicillin is clearly beneficial in lowering the incidence of intra-abdominal and wound infections. A 12- to 48-hour length of administration of antibiotics after operation is as effective as regimens of longer duration, although presently used dosages may be inadequate in severely injured patients. Adjunctive surgical maneuvers such as peritoneal irrigation with saline-containing antibiotic(s) remain controversial. Perioperative use of antibiotic prophylaxis, coupled with early operation and appropriate surgical technique, results in a 4.4% rate of intra-abdominal abscesses and a 5.1% rate of wound infections after laparotomy for abdominal trauma in modern trauma centers.

Penetration of prophylactic antibiotics into peritoneal fluid

This study evaluates the penetration of cephalosporins into the peritoneal fluid. Forty-six patients scheduled for abdominal surgery were randomized into three groups. On call to the operating room each patient was given a single 1 g dose of cefazolin, cefuroxime, or ceftazidime. Samples of the peritoneal fluid and blood were simultaneously obtained immediately after opening the peritoneal cavity. The mean serum cefazolin concentration was the highest. High peritoneal fluid levels of all three antibiotics were found; however, the antibacterial activity against common intestinal pathogens varied significantly. Cefazolin is the only study drug that possesses marginal in vitro activity against Streptococcus faecalis, a species generally considered resistent to cephalosporins. This study suggests that prophylactic second and third generation cephalosporins are not superior to cefazolin.

Review of the new second-generation cephalosporins: cefonicid, ceforanide, and cefuroxime

The new second-generation cephalosporins, cefonicid, ceforanide, and cefuroxime, have recently become available. These agents are generally less active against gram-positive cocci than first-generation cephalosporins and, at best, equal to cefoxitin and cefamandole against many gram-negative bacteria. Cefuroxime, however, is the most active cephalosporin for beta-lactamase-producing Haemophilus influenzae. These newer agents have superior pharmacokinetic characteristics over cefoxitin and cefamandole. Smaller doses, longer dosing intervals and, potentially, a reduction in total drug cost may be the real advantage of these agents. Open trials and a limited number of comparative studies have documented the effectiveness of cefonicid, ceforanide, and cefuroxime in the treatment of most mild-to-serious infectious diseases, although failures with cefonicid in the treatment of staphylococcal infections have been reported. Notably, cefuroxime has received approval for the treatment of common pediatric bacterial meningitis infections. Replacement of cefamandole or cefoxitin with one of these "longer-acting" agents may be cost-beneficial; however, clinicians must be on alert for the development of bacterial resistance or decreased efficacy.