Increased peritoneal fluid lactic acid values and progressive bowel strangulation in dogs.

In the present study, we determined values for peritoneal fluid and blood ammonia, amylase, and lactic acid content in 11 dogs after experimental bowel strangulation. In the nine survivors of this group, we demonstrated a near linear increase in peritoneal fluid lactic acid over a 24-hour period, during which the plasma lactic acid remained relatively constant. A significant increase in peritoneal fluid ammonia was also demonstrated, but this did not occur until more than 16 hours after strangulation. In a second group of two dogs in which simple obstruction was produced, no significant increase in peritoneal fluid lactic acid or ammonia occurred. We did not find significant changes in peritoneal fluid amylase in this study. These data suggest that the determination of peritoneal fluid lactic acid content, especially when compared with concomitant plasma lactic acid, may be useful in the accurate preoperative diagnosis of bowel strangulation.