Clinical determination of preoperative and postoperative intra-abdominal pressures in dogs

Intra-abdominal pressure (IAP) was indirectly measured, using a transurethral catheterization technique, in 20 client-owned dogs before and after elective ovariohysterectomy. Mean preoperative IAP was 4.50 +/- 0.44 cm H2O. Elective abdominal surgery caused significant elevations in mean postoperative IAP (mean 7.50 +/- 0.45 cm H2O, range 0 to 15 cm H2O) that persisted for at least 24 hours. However, the increase in IAP caused no clinically evident complications; thus, after elective abdominal surgery an elevation in IAP up to 15 cm H2O is to be expected. Intra-abdominal pressure was also measured in 20 consecutive clinical cases with gross abdominal distension, before or after laparotomy, or both. Included in this group were dogs with gastric dilation and volvulus, closed pyometra, hemoperitoneum, acute ascites, and diaphragmatic hernias. All dogs with gross abdominal distension had an elevated IAP (> or = 16 cm H2O) either before or after surgery. Severe elevations of IAP were associated with anuria in two dogs, necessitating surgical decompression; one with hemoperitoneum (47 cm H2O) and one after repair of a chronic diaphragmatic hernia (30 cm H2O).