Clinical findings for dogs undergoing elective and nonelective cholecystectomies for gall bladder mucoceles

Histologic findings of gastrointestinal biopsies and clinical outcome in dogs undergoing cholecystectomy for gallbladder mucoceles: 71 cases (2014-2021)

OBJECTIVES

To determine the presence and categorise the severity of enteritis in dogs with gallbladder mucoceles, and evaluate for any associations with enteritis. This study also aimed to report clinical outcome following cholecystectomy and evaluate for associations with survival.

MATERIALS AND METHODS

Medical records were retrospectively reviewed (2014 to 2021) for dogs undergoing cholecystectomy and duodenal biopsy procedures for gallbladder mucocele. Signalment, bloodwork, abdominal ultrasound findings, surgical details, histology results and outcomes were reported. Surgeries were considered elective or emergent based on each dog's clinical presentation. Enteritis was categorised based on cell type and severity. Inflammation and clinical outcome were statistically evaluated.

RESULTS

Seventy-one dogs met the study criteria. Enteritis was present in 85.9% (61/71) of cases with the majority being lymphoplasmacytic (53.5%). Twelve dogs (16.9%) underwent gastrointestinal biopsies from multiple sites, which revealed the same enteritis type at each location. A total of 87.3% (n = 62) dogs survived, including 90.4% elective and 86% emergent cases. No significant differences in enteritis severity or patient survival were found between elective and emergent cases. Septic peritonitis was diagnosed in two dogs (2.82%). Mortality was significantly associated with leukocytosis, with nonsurviving dogs having a mean WBC count of 27.6 G/L (95% confidence interval: 10.6 to 21.5).

CLINICAL SIGNIFICANCE

Enteritis is present in a majority of dogs with gallbladder mucocele, especially mild to moderate with lymphoplasmacytic cell type. Obtaining a duodenal biopsy had minimal impact on patient outcome. Compared to previous studies, improved survival in emergent cases was noted. Further studies with long-term follow-up are needed to determine if enteropathy-related signs persist after cholecystectomy.

Increased lipogenesis and lipidosis of gallbladder epithelium in dogs with gallbladder mucocele formation

BACKGROUND

Gallbladder disease in people is frequently associated with disorders of lipid metabolism and metabolic syndrome. A recently emergent gallbladder disease of dogs, referred to as mucocele formation, is characterized by secretion of abnormal mucus by the gallbladder epithelium and is similarly associated with hyperlipidemia, endocrinopathy, and metabolic dysfunction. The cause of gallbladder mucocele formation in dogs is unknown.

METHODS

A prospective case-controlled study was conducted to gain insight into disease pathogenesis by characterization of plasma lipid abnormalities in 18 dogs with gallbladder mucocele formation and 18 age and breed matched control dogs using direct infusion mass spectrometry for complex plasma lipid analysis. This analysis was complemented by histochemical and ultrastructural examination of gallbladder mucosa from dogs with gallbladder mucocele formation and control dogs for evidence of altered lipid homeostasis of the gallbladder epithelium.

RESULTS

Gallbladder mucocele formation in dogs carried a unique lipidomic signature of increased lipogenesis impacting 50% of lipid classes, 36% of esterified fatty acid species, and 11% of complex lipid species. Broad enrichment of complex lipids with palmitoleic acid (16:1) and decreased abundance within complex lipids of presumptive omega-3 fatty acids eicosapentaenoic (20:5) and docosahexaenoic (22:6) was significant. Severe lipidosis of gallbladder epithelium pinpoints the gallbladder as involved causally or consequently in abnormal lipid metabolism.

CONCLUSION

Our study supports a primary increase in lipogenesis in dogs with mucocele formation and abnormal gallbladder lipid metabolism in disease pathogenesis.

Determining the patency of biliary tracts in dogs with gallbladder mucocele using near-infrared cholangiography with indocyanine green

Cholecystectomy is indicated for gallbladder mucoceles (GBM). Evaluating the patency of the biliary duct and precise biliary tree visualization is crucial for reducing the risk of compromised bile flow after surgery. Therefore, intraoperative cholangiography (IOC) is recommended during cholecystectomy to prevent biliary tract injury. Although indocyanine green (ICG) cholangiography has been extensively reported in human medicine, only one study has been conducted in veterinary medicine. Therefore, this study aimed to demonstrate the use of ICG for IOC to identify fluorescent biliary tract images and determine the patency of the common bile duct during cholecystectomy in dogs. This study comprised 27 dogs, consisting of 17 with gallbladder mucoceles (GBM) and 10 controls, specifically including dogs that had undergone elective cholecystectomy for GBM. ICG injection (0.25 mg/kg) was administered intravenously at least 45 minutes before surgery. During the operation, fluorescent images from cholangiography were displayed on the monitor and obtained in black-and-white mode for the comparison of fluorescence intensity (FI). The FI values of the gallbladders (GBs) and common bile duct (CBD) were measured using FI analyzing software (MGViewer V1.1.1, MetapleBio Inc.). The results demonstrated successful CBD patency identification in all cases. Mobile GBM showed partial gallbladder visibility, whereas immobile GBM showed limited visibility. Additionally, insights into the adequate visualization of the remaining extrahepatic biliary tree anatomy were provided, extending beyond the assessment of CBD patency and gallbladder intensity. Our study demonstrates the potential of fluorescent IOC using intravenous injection of ICG for assessing the patency of the cystic duct and common bile duct during cholecystectomy in patients with GBM, eliminating the need for surgical catheterization and flushing of the biliary ducts. Further research is warranted to investigate and validate the broader applicability of ICG cholangiography in veterinary medicine.

Occurrence and clinical relevance of postoperative hypernatremia in dogs undergoing cholecystectomy

BACKGROUND

Patients undergoing cholecystectomy have not been reported previously to develop clinically relevant postoperative hypernatremia.

OBJECTIVES

Describe the frequency of postoperative hypernatremia in dogs undergoing cholecystectomy and its clinical relevance (duration of hospitalization and survival).

ANIMALS

Thirty-seven dogs undergoing cholecystectomy at 2 private referral hospitals.

METHODS

Retrospective study of dogs undergoing cholecystectomy with available preoperative and postoperative serum sodium concentrations.

RESULTS

Postoperative hypernatremia (>150 mEq/L) was common (56%; 95% confidence interval [CI], 40%-70%) and was associated with significantly higher mortality compared to nonhypernatremic patients (52%; 95% CI, 30%-70% vs 12.5%; 95% CI, 2%-40%; P = .02). Nonsurvivors had higher mean postoperative peak serum sodium concentrations (155 mEq/L; range, 146-172) than survivors (150 mEq/L; range, 142-156; P = .01). Dogs developing hypernatremia within 6 hours after surgery had 7.7 higher odds of nonsurvival (odds ratio [OR], 7.7; 95% CI, 5.9-9.4). A delta value (serum sodium concentration on admission [T0] - serum sodium concentration 6 hours postoperatively [T2]) of ≥10 mEq/L carried 3.3 higher odds of mortality (OR, 3.3; 95% CI, 1.6-5.1). All dogs with a postoperative peak sodium concentration >160 mEq/L did not survive. Admission acute patient physiologic laboratory evaluation fast (APPLEfast ) scores were not different between survivors and nonsurvivors or between postoperative hypernatremic and normonatremic patients. Hospitalization time was no different between hypernatremic and normonatremic patients (6 days vs 4.5 days; P = .15). Dogs with gallbladder mucocele were more likely to develop postoperative hypernatremia and have poorer outcomes.

CONCLUSIONS

Hypernatremia was a common and clinically relevant postoperative complication in dogs after cholecystectomy. Detection of hypernatremia within 6 hours after surgery may be associated with poorer outcomes.

Clinical Outcomes in Dogs Undergoing Cholecystectomy via a Transverse Incision: A Meta-Analysis of 121 Animals Treated between 2011 and 2021

Although many studies have been conducted on the use of median and transverse incisions in various surgeries in the field of human medicine, related studies in veterinary medicine are lacking. This study aimed to present treatment options for dogs requiring cholecystectomy by reporting the pros and cons of 121 cholecystectomies performed via transverse incision at our hospital over 10 years. In most included cases, nonelective cholecystectomy was performed in an unstable emergency situation. The perioperative mortality rate was 23.14%, which was not significantly different from that of cholecystectomy performed via the conventional midline approach. However, the overall operation time (46.24 ± 6.13 min; range 35-65 min) was shortened by securing an adequate surgical field of view. The transverse incision approach facilitates fast and accurate surgery without increasing the fatality rate in small-breed dogs, in whom securing an adequate surgical field of view is difficult. Thus, transverse incision should be actively considered in dogs undergoing cholecystectomy due to emergency conditions, such as bile leakage or biliary tract obstruction, since prolonged anesthesia can be burdensome. This study may improve cholecystectomy outcomes in small-breed dogs with difficult-to-secure surgical fields.

Laparoscopic cholecystectomy using the subserosal layer dissection technique in dogs: 34 cases (2015‐2021)

OBJECTIVES

To describe a standardised subserosal layer dissection technique and evaluate its outcomes in canine laparoscopic cholecystectomy.

MATERIALS AND METHODS

Medical records of dogs undergoing laparoscopic cholecystectomy using the standardised subserosal layer dissection technique for the treatment of cholecystolithiasis, cholecystitis, and gall bladder mucocele at a single veterinary hospital from January 2015 to September 2021 were extracted. Operative time, subserosal layer dissection achievement rate, open conversion rate, and complication rate were evaluated.

RESULTS

Thirty-four dogs were included. The most common preoperative diagnosis was cholecystolithiasis (n=29). Operative time was 190 minutes (range: 110 to 330 minutes). Subserosal layer dissection of more than 90% of the gall bladder bed was achieved in 27 (79%) dogs. Conversion to open surgery was required in three (8.8%) dogs. There were no cases of intraoperative bleeding, bile duct injury, or reoperation.

CLINICAL SIGNIFICANCE

This study showed that laparoscopic cholecystectomy using the standardised subserosal layer dissection technique could be performed successfully in dogs. Future prospective clinical studies are needed to determine safety and effectiveness of this technique compared to standard techniques.

Preoperative serum C-reactive protein concentration can be used to detect gallbladder rupture in dogs with gallbladder mucocele

OBJECTIVE

To determine whether serum C-reactive protein (CRP) concentration could be used to detect gallbladder rupture (GBR) prior to surgery in dogs undergoing cholecystectomy for treatment of gallbladder mucocele (GBM).

ANIMALS

45 dogs that underwent cholecystectomy because of GBM at a companion animal referral hospital from 2017 to 2020.

PROCEDURES

Electronic medical records were reviewed, and dogs were included if serum CRP concentration had been measured within 24 hours prior to cholecystectomy. Dogs were grouped as to whether the gallbladder was found to be ruptured or intact during surgery. Accuracy of using preoperative CRP concentration to predict GBR was compared with accuracy of abdominal ultrasonography and other preoperative blood tests.

RESULTS

GBR was present in 15 dogs at the time of surgery. Median preoperative CRP concentration was significantly higher in dogs with GBR (15.1 mg/dL; interquartile range, 7.4 to 16.8 mg/dL) than in dogs with an intact gallbladder (2.65 mg/dL; interquartile range, 0.97 to 13.4 mg/dL). Sensitivity, specificity, and accuracy of using preoperative CRP concentration to predict GBR were 100%, 67%, and 78%, respectively.

CLINICAL RELEVANCE

Measurement of preoperative CRP concentration provided excellent sensitivity and moderate specificity for detection of GBR in dogs undergoing cholecystectomy because of GBM. Accuracy of using preoperative CRP concentration for detection of GBR was not superior to the accuracy of preoperative abdominal ultrasonography. However, when CRP concentration was combined with results of ultrasonography, the sensitivity, specificity, and accuracy for detection of GBR were 100%, 93%, and 96%, respectively.