Yukihiro Akiya

The usefulness of conducting investigations on intra-abdominal bacterial contamination in digestive tract operations.

A bacteriological study of 108 cases of gastrointestinal surgery was conducted by analyzing intra-abdominal bacterial contamination (IABC) and postoperative surgical site infections (SSI). We utilized an anaerobic porter to detect intra-abdominal bacterial infection and transport bacteria to the laboratory. The positive IABC rate was 42.9% for gastric cancer surgery, 22.6% for biliary tract surgery, and 85.7% for colorectal cancer surgery. Most cases of SSI were IABC-positive, and isolated bacterial species from the SSI were similar to those from the IABC. In colorectal cancer surgery, a preoperative chemical intestinal preparation and the prophylactic use of antibiotics had a major influence on the sensitivity of bacteria isolated from the SSI. These data suggest that prophylactic antibiotics should be chosen from among those to which bacteria from the IABC are highly sensitive, and that therapeutic antibiotics should be chosen from among those to which bacteria isolated from the SSI are highly sensitive. Finally, the exploration of IABC enables us to predict the incidence of SSI.

Increases in pulmonary artery pressure and cardiac output due to the inhibition of nitric oxide synthesis during operative stress

Pulmonary artery pressure (PAP), cardiac output (CO), and urinary nitrate, a stable endproduct of nitric oxide (NO), were measured pre- and postoperatively in eight patients who underwent esophagectomy for squamous cell carcinoma of the thoracic esophagus. A significant elevation of PAP and CO on the day of operation (POD 0) was accompanied by a low concentration of urinary nitrate. A reduction in PAP and CO, and an increase in nitrate to the preoperative levels, were found on PODs 2 and 3, respectively, but urinary nitrate decreased again after POD 3. Consequently, the changes in PAP and CO were closely correlated with the nitrate concentration. These results suggest that operative stress inhibited NO synthesis with a transitory induction of endogenous NO synthesis postoperatively.