T. Justesen

Wound sepsis after elective cholecystectomy. Restriction of prophylactic antibiotics to risk groups.

This prospective study of elective cholecystectomy investigated the frequency and type of bacteria in gallbladder bile at operation, the factors predicting the presence of bacteria in bile, and the relationship between bacteria in bile and subsequent wound sepsis. In 148 consecutive cases 23% of bile cultures were positive. The overall wound infection rate was 15%, but 91% of all wound infections occurred in patients with positive bile cultures. Eighty-five per cent of all positive bile cultures and 86% of all wound infections occurred in 37% of the patients, characterized by age over 60 years and/or a history of previous attacks of acute cholecystitis. We suggest that in elective cholecystectomy prophylactic antibiotics should be restricted to this group of patients to limit the use of antibiotics.

Comparison of an open and a closed tube system for collection of jejunal juice.

When jejunal juice is obtained by means of open pernasal tubes, the risk of the aspirates being contaminated is presumably high. The present study compares jejunal aspirates obtained from an open and from a closed tube system. Ten patients suspected of having abnormal jejunal flora and five healthy human volunteers were investigated. The pH values of aspirates obtained from the open tubes were significantly lower than the values registered in aspirates from the closed tube system, with a median difference of 0.70 (p less than 0.02). No differences between the two types of aspirate were registered with regard to total number of bacteria, number of bacterial species, lipase, total protein, total amylase or its fractions of pancreatic and salivary isoamylases. For the investigation of pH-sensitive substances in jejunal juice, a closed tube system is therefore recommended, whereas the use of such a device does not seem necessary for the study of bacterial microflora and pancreatic enzymes.

Bacterial Flora of the Small Intestine and Bile Acid Metabolism in Patients with Hepatico-Jejunostomy Roux-en-Y

Duodenal and jejunal bacterial flora and bile acid metabolism were investigated in 14 patients with hepatico-jejunostomy Roux-en-Y. Anaerobic culture procedures were based on the use of a glove-box with an oxygen-free atmosphere and pre-reduced, anaerobically sterilized media. Anaerobic transport was based on evacuation of atmospheric air from transport-tubes and transport-time less than 30 minutes. Bile acid metabolism was evaluated from concentrations of toal bile acids and deconjugated bile acids, glycine/taurine ratio and breath test. In 92 per cent of the patients an abnormal flora-containing anaerobic and/or aerobic bacteria was found in the most proximal part of the jejunum at the site of the entero-entero anastomosis (cf. Fig. 1 and Table 1). Total bile acid concentrations were low in half of the patients, whereas deconjugated bile acids or elevated glycine/taurine ratio was found in one patient only (cf. Table II). An abnormal breath test was found in 5 patients, but without any clear correlation between the breath test and the bacterial flora.

Tube for Sampling of Uncontaminated Small-Bowel Juice

A tube system for the collection of uncontaminated small-bowel juice is described. It consists of an outer guide tube, its distal end being closed by a membrane, and an inner aspiration tube. When the outer tube is placed at the desired site of aspiration, the membrane is perforated by advancing the sterile inner tube. The device was tested in 90 healthy human volunteers. The procedure was completely or partly unsuccessful in 9 cases (95% confidence limits, 4.7-18.0). Median intubation time was 12 min; range, 5-14 min. The time used for aspiration of 5 ml of intestinal juice varied from 1 to 30 min; median, 10 min. The site of aspiration in jejunum distal to the ligament of Treitz varied from 0 to 14 cm; median, 3 cm. No complications of the procedure were registered.

Experimental animal model of surgical wound infection applicable to antibiotic prophylaxis.

Wound infection, defined as accumulation of pus draining spontaneously or after opening of the Wound, developed in 19 out of 22 guinea pigs (86 %) after intraincisional contamination with 107Escherichia coli plus 108Bacteroides fragilis before wound closure. Antibiotic prophylaxis with gentamicin plus clindamycin significantly reduced the wound sepsis rate from 86 % to 29 % (p<0,001). Pus for bacteriological studies was available in all cases of wound infection but one, and culture always revealed bothEscherichia coli andBacteroides fragilis. The animal model Presented employs widely accepted criteria for wound infection, and avoids culture of tissue homogenates.

Wound infection rates after intraincisional plus systemic antibiotic prophylaxis in an animal model.

The effect of intraincisional application of antibiotics in addition to systemic antibiotic prophylaxis was evaluated in a randomized blind study using a guinea pig model of surgical wound infection. Wounds were contaminated with 107Escherichia coli plus 108Bacteroides fragilis. Wound infection was defined as accumulation of pus draining spontaneously or after opening the wound. Systemic antibiotic prophylaxis with gentamicin plus clindamycin significantly reduced the wound sepsis rate from 83% in the control group to 20% in the treated group (p < 0.001). Intraincisional application of antibiotics in addition to systemic prophylaxis did not further reduce the rate of wound sepsis (p > 0.8).

Wound infection rates following preoperative versus intraoperative commencement of antibiotic prophylaxis

The effect of antibiotic prophylaxis initiated one hour prior to contamination or at the time of contamination was evaluated in a randomized blind study using a guinea pig model of surgical wound infection. Wound infection, defined as accumulation of pus draining spontaneously or after opening of the wound, developed in 135 guinea pigs after intraincisional contamination before wound closure with 107Escherichia coli plus 108Bacteroides fragilis. Antibiotic prophylaxis with gentamicin plus clindamycin significantly reduced the wound sepsis rate from 82 % in the control group of 61 animals to 19 % in the two treated groups of 68 and 67 animals (p<0.001). However, the timing of antibiotic prophylaxis did not influence wound sepsis rates, rectal temperature during the postoperative period, or bacterial recovery from wound infections.

Pediatric tube system for collection of uncontaminated jejunal juice.

Summary: A tube system for collection of uncontaminated jejunal juice in children is described. It consists of an outer tube, the distal end of which is closed with a membrane, and an inner aspiration tube. When the outer tube is positioned at the site of aspiration, the membrane is perforated by applying air pressure through the outer tube. The tube was tested in 72 Danish children. With only one intubation having to be repeated, aspiration was achieved in all the children (95% confidence limits, 92.60‐99.97%). The median intubation time was 10 min (range, 2‐35 min). Mean time for aspiration of 1 ml of jejunal juice varied from 1 to 30 min (median, 5 min). The site of aspiration in the jejunum—expressed as the position of the tip of the inner tube—was from 0 to 6 cm distal to the ligament of Treitz (median, 3 cm). There were no complications.