RUPTURE OF THE URINARY-BLADDER AND URACHUS IN NEWBORN FOALS - A REVIEW OF THE LITERATURE

It is well documented that the incidence of rupture of the urinary bladder or urachus is highest in newborn male foals and occurs during the (usually uncomplicated) parturition. Important clinical symptoms include frequent passing of small quantities of urine, abdominal distention and positive abdominal undulation. Hyperkalaemia, hyponatraemia, hypochloraemia and an elevated serum creatinine level are often present. The serum blood urea nitrogen concentration may be normal or only slightly elevated. The creatinine concentration in the peritoneal fluid is invariably higher than that in serum, and this finding is of importance in the diagnosis. A method for field diagnosis of bladder rupture is to instill a sterile solution of a dye into the bladder followed by its retrieval in the peritoneal fluid. Surgical treatment is indicated as soon as possible after diagnosis. Prior to inducing anaesthesia (oxygen, nitrous oxide and halothane by mask), fluid losses and electrolyte imbalance should be corrected and slow decompression of the abdomen should be performed in order to reduce the risk of cardiac dysrhythmias and hypovolaemic shock. The bladder defect is usually closed in two layers of inverting continuous sutures. If the diagnosis of bladder rupture is timely established, its prognosis is usually favourable.