Evaluation of transvesical intra-abdominal pressure measurement in hospitalized dogs

Objectives - To (1) evaluate intra-abdominal pressure (IAP) measurements in dogs with possible risk factors for the development of intra-abdominal hypertension (IAH); (2) determine intra-observer variability of IAP measurements; and (3) determine interobserver variability of IAP measurements. Design - Prospective, observational, pilot study. Setting - Veterinary teaching hospital. Animals - Fourteen client-owned dogs, requiring urinary catheterization, admitted to the ICU. Interventions - Using the risk factors for IAH established for human patients as defined by the World Society of Abdominal Compartment Syndrome, dogs were assigned to either an IAH risk or no risk group. A commercially available IAP monitoring system was used to obtain 3 direct, transvesical IAP measurements. The primary investigator obtained the first 2 IAP measurements. A secondary investigator obtained the third IAP measurement. Measurements and Main Results - Dogs in the IAH risk group (n = 9/14) had significantly higher mean IAPs (9.4 +/- 3.4 mm Hg) than dogs in the no risk group (n = 5/14; 4.1 +/- 0.9 mm Hg) (P < 0.05). Measurements recorded by the primary investigator were compared to determine intra-observer variability. Pearson's correlation coefficient was 0.98 (P < 0.0001). Bland-Altman analysis determined a mean difference in IAP measurements of -0.3 mm Hg (95% confidence interval from 0.13 to -0.71 mm Hg) indicating an intra-observer variability of less than 0.8 mm Hg. Measurements recorded by the primary and secondary investigator were compared to determine interobserver variability. Pearson's correlation coefficient was 0.95 (P < 0.0001). Bland-Altman analysis determined a mean difference in IAP measurements of 0 mm Hg (95% confidence interval from 1.1 to -1.1 mm Hg) indicating an interobserver variability of less than 2.0 mm Hg. Conclusions - Dogs with predefined human risk factors for IAH had higher IAP than dogs without risk factors. IAP monitoring appears to have low variability within and across observers.