Analysis of pH, pO2 and pCO2 in drainage fluid allows for rapid detection of infectious complications during the follow-up period after abdominal surgery.

Low pH (< 7.1) and pO2 (< 6.5 kPa) and high pCO2 (> 8 kPa) of peritoneal fluid have been previously associated with the presence of intra-abdominal infection. These parameters were monitored in drainage fluid following emergency laparotomy in 40 patients operated on for intra-abdominal infections and also in 15 patients who underwent laparotomy for another reason than infection. Significant differences were observed beginning on the fourth postoperative day between the 48 patients who improved or were cured and the seven patients in whom therapy failed due to anastomotic breakdown or abscess formation. Anastomotic leaks or abscesses were radiologically confirmed. In five of the seven failures, complications were first detected by analysis of pH, pO2 and pCO2 before clinical symptoms became evident. Specificity for each of these parameters in drainage fluid samples obtained after the second postoperative day was > 94%. Assessment of the three parameters allowed for simple, cost-effective, rapid and early detection of infectious complications following abdominal surgery.