Peritoneal fluid lactic acid and diagnostic dilemmas in acute abdominal disease.

Our previous canine research suggested that the determination of peritoneal fluid lactic acid levels may be helpful in the evaluation of potential acute abdomen cases. To investigate the clinical significance of those findings, we obtained simultaneous peritoneal and plasma lactic acid values from patients undergoing emergency celiotomy or in whom surgical consultation was sought to rule out an acute abdomen. The lactic acid value was significantly higher in peritoneal fluid than in plasma in patients who were found to have hollow viscus perforation, gangrenous intestine, peritonitis, or intra-abdominal abscess. In contrast, the values were similar in patients who did not have those conditions. Our findings suggest that the calculated difference between simultaneous peritoneal and plasma lactic acid values is a helpful diagnostic index for patients in whom the diagnosis of acute abdomen is not otherwise obvious.