For congenital extrahepatic portosystemic shunts (PSS) have been treated with surgical ligation of the primary shunting vessel along with the cnservative therapy. However, in some cases, the complete ligation of the anomalous vessel would result in life-threatening portal hypertension caused by increased resistance of blood flow through a poorly developed hepatoportal vascular system. Gradual occlusion of shunt vessels with the ameroid constrictor (AC) has been reported to prevent such acute problems. In this study, we performed the surgical treatment with AC in 4 young dogs with clinical signs of PSS. Three of 4 dogs had an extrahepatic portocaval shunt and the remaining one had a portoazygos shunt. After the treatment with AC, any signs associate with portal hypertension did not appear and their clinical conditions were improved quickly. AC can slow down the occlusion rate of the shunting vessel, which may allow more time for hepatic regeneration to accommodate increased portal blood flow to the liver and prevent from the portal hypertension and the subsequent development of multiple collateral shunts. It is also suggested that measurement of portal pressure may not be necessary when the shunt vessel is occluded by AC.

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This study was undertaken to examine the applicability and usefulness of one lung ventilation (OLV) in canine surgeries. The cardiovascular parameters and blood gas were analysed in dogs that had left OLV during general anesthesia for 60 min and the following 90 min under thoracentesis. In the OLV group of 6 dogs, mean pulmonary arterial pressure and pulmonary vascular resistance increased gradually in comparison with the two lung ventilation group of 6 dogs. However, the arterial O₂ tension decreased remarkably to 87, 6 mmHg with the lowered arterial pH, although arterial CO₂ tension increased during OLV. In conclusion, dogs with OLV have the disadvantage of the deterioration of respiratory condition in spite of hypoxic pulmonary vasoconstriction. Therefore, it is necessary to use assisted ventilation or other improvement to prevent atalectasis, for the safer application of OLV in dogs.

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We examined the effect of intravenous (IV) rapid infusion of hypotonic Ringer's (RG) or Hartmann's replacement solutions with glucose (HG) on the hemodynamic status and acid-base equilibrium of heifers. Six heifers were equally divided into two groups. The animals were given 30 ml/kg of either RG or HG (20ml/kg/hr), and were monitored for 360 min after the initiation of fluid replacement. The RG and HG infusion induced an increase in relative plasma volume (rPV), reaching 124.6±12.1 % and 133.2±10.4 % at the end of fluid replacement. No changes were seen in the arterial pressure or plasma osmotic pressure. Infusion of RG induced diluted acidification, resulting from significant decreases in venous blood pH (-0.068), bicarbonate (-2.67 mmol/l) and base excess concentrations (-3.67 mmol/l) compared to pre infusion values. No significant changes were observed in these parameters in the HG group ; HG infusion inhibited diluted acidification. Thus, it appears that 30 ml/kg of hypotonic solution at a flow rate of 20 ml /kg/hr can be safely infused into cattle. Infusion of HG may be more beneficial than RG for rehydrating cattle with metabolic acidosis.

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Bone-invasive acanthomatous epulis located in the caudal area of oral cavity was diagnosed in three dogs. The mean age of the patients was 12.3 years old. In all three dogs, the tumor went into complete remission with surgical excision combined with radiation therapy. Two dogs were still alive and the remaining one died of the cause not related to the tumor, renal failure. The mean progression-free survival time was 30.3 months. Malignant transformation was not observed in any cases.

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