INDIRECT MEASUREMENT OF ABDOMINAL PRESSURE IN HORSES
Paulo Aléscio Canola; João Henrique Perotta; Déborah Martins Penteado Dias; Júlio
Carlos Canola; Carlos Augusto Araújo Valadão
Introduction: The abdomen and its constituents might be considered not compressive
and exclusively fluid-filled in character, and by that it is submitted to the Pascal’s law.
Because of that the abdominal pressure (Pab) might be measured in almost any part of
the abdomen. In human beings, the homogeneous transmission of the pressure inside the
abdomen allows it to be estimated by bladder, rectum or stomach. Objectives: Evaluate
the correlation between vesical (Pves) and abdominal (Pab) pressures in horses.
Material and Methods: A catheter with a balloon manually built was used for in vitro
tests and in vivo measurement of the Pves for comparison with the real Pab values. For
that seven mares were used and the Pves obtained after insufflation of the balloon with
2,0ml of air and distention of the bladder with 3,0ml.kg-1 of saline after previously
empting it. Results: There was difference (p•0,05) between both variables in all animals
studied. Discussion: Possibly there was an excessive distention of the bladder that could
be responsible for the lack of correlation between the variables. The wall of the bladder is
not merely a membrane that is capable of transcript the abdominal pressure to its interior.
The compliance of the bladder wall varies in between patients and it is dependent of age,
weight and filling capacity. Instead of that the stress of the manipulation and placement
of the catheter might have contributed for this to happen because the functioning of the
bladder in horses is mediated by alga and beta adrenergic receptors. High levels of
circulating catecholamine also might be the responsible for the high values of the Pves
compared to the Pab. Although other studies measured the Pves and found higher values
than those observed in here, but they are also different from the real Pab values. In
human beings this technique is considered the gold standard for measuring the Pab.
Conclusions: This was the first attempt to estimate the Pab by Pves values in horses.
Based on the results obtained here there is no correlation between Pves and Pab values
for horses as strongly suggested in human beings. Therefore this reinforces the
questioning of other authors that the abdominal pressure might not follow the Pascal’s
law as sugested.
Author adress: Alameda Zenon Vargas da Silva, 170. Jaboticabal – SP. CEP: 14883-344.
[email protected].
Ethical Committee: CEBEA FCAV – UNESP- Jaboticabal protocol nº 024177-05.
Author adress: Alameda Zenon Vargas da Silva, 170. Jaboticabal – SP. CEP: 14883-344.
[email protected].