CANINE MEDICINE agulation factors . Continue therapy until bile flow is normal , typically two to four days after surgery .
During surgery , a complete abdominal exploratory is recommended so that concurrent or occult problems can be identified and addressed . While several surgical techniques are described , cholecystectomy has many advantages , as removal of the gallbladder prohibits secondary gallbladder infection and rupture . 18 Other surgeries that have been described include cholecystotomy , cholecystoduodenostomy , and cholecystojejunostomy . 25 Cholecystotomy is a suboptimal choice given the disease process and possible associated gallbladder wall compromise .
The surgical evaluation should also include expressing or cannulating the common bile duct , performing liver biopsy , and collecting bile and liver samples for aerobic and anaerobic culture . In patients with biliary rupture , extensively flush the peritoneal cavity , and place abdominal drains .
Perioperative care includes broad-spectrum antibiotics ( adjusted based on culture results ), hepatoprotectants , and a low-fat diet . The most common complications of cholecystectomy include pancreatitis and bile peritonitis ; death is also common . 14 , 17 , 18 Chronic vomiting occurs infrequently . The perioperative mortality rate associated with cholecystectomy is moderate , with 22 % to 40 % of patients dying within 14 days
14 , 17 , 18 of surgery .
Patients that survive this period have excellent longterm survival rates . In general , the morbidity and mortality rates of patients with extrahepatic biliary duct obstruction undergoing biliary diversion procedures are higher than those undergoing cholecystotomy . 26 Unfortunately , no reliable predictors for survival exist .
Medical Management Medical management can be considered in asymptomatic and mildly symptomatic patients without evidence of extrahepatic biliary duct obstruction or gallbladder rupture , as long as the clinician and client are aware of the potential complications . 1 , 21
Antibiotics . Because some mucocoeles are associated with bacterial infection , performing an ultrasound-guided cholecystocentesis to obtain a sample for aerobic and anaerobic bacterial culture is recommended . Although considered relatively safe , rare complications of percutaneous cholecystocentesis may include bile leakage , bradycardia due to a vasovagal reaction , bacteremia , and local hemorrhage . 27,28 Studies have indicated that risks associated with percutaneous cholecystocentesis in normal dogs and those with cholecystitis are minimal , but complication rates have not been determined in dogs with mucocoeles . 27 , 29 If bacteria are isolated , a six- to eight-week course of antibiotics is recommended . Gram-negative anaerobes are the most common bacteria isolated , but infections may be mixed . For this reason , antibiotic therapy with a combination of two medications is often pursued . In cases in which ultrasound-guided cholecystocentesis is not feasible , empirical antibiotic therapy should be prescribed ( Table 2 ). 21 Use caution when prescribing antibiotics in patients with hepatic insufficiency since they may be unable to metabolize certain antibiotics appropriately .
Choleretics . Choleretics , drugs that stimulate hepatic bile excretion , should be administered ( Table 2 ). Ursodiol ( ursodeoxycholic acid ) is a naturally occurring bile acid that increases bile flow by decreasing the cholesterol content of bile and thinning biliary secretions by producing bicarbonate-rich enhanced bile flow . Ursodiol is also considered hepatoprotective since it reduces the hepatotoxic effects of bile salts and protects liver cells from endogenous hydrophobic bile acids such as lithocholate and deoxycholate . 30 It is important to note that ursodiol is contraindicated in cases of extrahepatic biliary duct obstruction . Anecdotally , mucocoeles have recurred after ursodiol discontinuation .
Other hepatoprotectants . Silymarin ( milk thistle ) should also be instituted ( Table 2 ). This nutraceutical alters the composition of hepatocyte membranes and limits the entry of hepatotoxins into cells . 31 It also stimulates protein synthesis and hepatic regeneration . 31 Silymarin contains flavonoids such as silybin , silydianin , and silychristin , which increase glutathione concentrations and provide antioxidant effects . 31 Inhibition of the inflammatory effects of leukotrienes is also reported . 31
S-adenosylmethionine ( SAMe ) is a precursor to glutathione and has antioxidant effects ( Table 2 ). 32 It also enhances DNA repair . 32 While studies clearly indicate that milk thistle and SAMe protect hepatocytes from damage , studies have not confirmed that either is useful in dogs with mucocoeles
31 , 32
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Monitoring . Re-examine dogs undergoing medical therapy for mucocoeles after four to six weeks . The recheck should include abdominal ultrasonography , a complete blood count , and a serum chemistry profile . In one report involving two dogs , alanine aminotransferase and alkaline phosphatase activities and total bilirubin concentrations remained elevated for weeks to months after ultrasonographic resolution of the mucocele . 1 These persistent elevations are most likely associated with the extension of pathological processes from the gallbladder to the liver or from a concurrent hepatic or endocrine ( e . g . hyperadrenocorticism , hypothyroidism , diabetes mellitus ) condition .
Prognosis . The prognosis for patients treated medically appears to be variable . In one study , seven of 25 patients with mucocoeles were treated with ursodiol and SAMe . Two died within two weeks , two were lost to follow-up , and three survived without complications for at least six months . 12 In a recent case study , two clinically ill patients with
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