Liver: lobectomy in Cats (Felis) | Vetlexicon
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Liver: lobectomy

ISSN 2398-2950


Synonym(s): Hepatic lobectomy

Introduction

  • Partial lobectomy implies removal of part of a liver lobe with parenchyma divided anywhere except the hilus.
  • Complete lobectomy implies removal at the level of the hilus.
  • Partial hepatectomy implies removal of more than one lobe at the same surgery.
  • Although guidelines for canine patients suggest up to 70% loss can be tolerated, there are no guidelines available for feline patients.

Uses

General considerations

  • ​In the cat, the common bile duct and the major pancreatic duct usually fuse before forming a common entry to the small intestine at the major duodenal papilla.
  • Congenital anomalies of the biliary tract are not uncommon in cats - up to 12% incidence - including duplicate gall bladder, divided gall bladder and multiple ductular bladders with one gallbladder. The majority of these are not of clincal significance and do not require intervention if noted at surgery.
  • If the hepatic disease has caused biliary obstruction Bile duct: disease, cats with prolonged biliary obstruction are at risk for coagulopathic problems due to malabsorption of vitamin K.
  • Many cats with liver tumors not infrequently have pre-operative azotemia Azotemia; this must be taken into account for anesthetic and perioperative management.

Requirements

Personnel

Anesthetist expertise

Materials required

Recommended equipment

  • Full surgical kit Surgical instruments including atraumatic forceps (eg Debakey, Adson-Brown); a range of hemostats of different sizes, both curved and straight; Mayo scissors (curved and straight); Metzenbaum scissors (curved and straight).
  • Surgical suction - both to remove lavage fluid and in case of significant hemorrhage.
  • Abdominal retractors, eg Balfour, Gosset appropriate for a feline patient size.
  • Hand held malleable retractors for use with a scrubbed assistant.
  • Surgical diathermy (bipolar and monopolar).
  • Vessel sealing devices (eg electrothermal bipolar system).
  • Good operating room lights +/- additional light sources.

Recommended consumables

  • Surgical stapling equipment facilitates surgery - in cats either 2.0 mm or 3.5 mm stapling devices are most appropriate.
  • Laparotomy sponges in addition to standard surgical swabs.
  • Gelatin sponges or oxidized regenerated cellulose can be useful for capsular oozing.
  • Monofilament absorbable suture, eg polydioxanone, poliglecaprone 25 Suture materials: absorbable.

Preparation

Other preparation

Preoperative

  • Ensure all necessary pre-operative tests have been performed, eg advanced imaging if there is doubt whether a tumor is resectable or to identify the presence of metastatic disease.
  • Ensure all necessary consumables are available in the appropriate sizes for a feline patient.
  • Cross-match blood Blood: crossmatching.

Restraint

Technique

Approach

Preparation and surgical approach

  • Dorsal midline recumbency with a wide area clipped and aseptically Surgery: asepsis prepped over the ventral abdomen.
  • In some cases additional exposure may require extension to a caudal sternotomy - ensure the clip and surgical prep incorporates this area if potentially necessary.
  • Routine midline celiotomy Laparotomy: midline approach from the xiphoid process caudally.
  • Place abdominal retractors over soaked sterile swabs to reduce abdominal wall bruising.
  • Once a full abdominal evaluation has been performed, the abdominal contents caudal to the liver can be covered with soaked swabs to reduce desiccation and contamination.

Core procedure

Partial lobectomy and complete lobectomy

  • Partial lobectomy and complete lobectomy can be performed by hand if necessary but more hemorrhage is likely intra-operatively than when using vessel sealing devices or surgical stapling equipment.
  • Partial lobectomy is done by gently crushing the parenchyma using the 'finger fracture' technique with ligation of individual blood vessels and bile ducts thus exposed.
  • Complete lobectomy by hand involves careful dissection of the liver around the hilus then individual vessel ligation. A single encircling ligature should not be used; if it dislodges or loosens at all then significant hemorrhage may ensue.
  • If using stapling devices, the 2.0 mm and 3.5 mm devices are best suited to cats.
  • Additional hemostatic control may be required to augment the staple line as the B-shape of staples doesn't always completely occlude vessels, eg gelatin sponge, vascular clips.
  • As with dogs, central and right lobectomies are more challenging due to the close proximity of major blood vessels including the vena cava.
  • Temporary inflow occlusion of the hepatic artery and portal vein has been suggested with either a bulldog vascular clamp or Rumel tourniquet but is not routinely performed in clinical practice.

Exit

Step 1 - Closure

  • Once the abdomen has been lavaged with 100-200 ml warmed sterile saline/kg bodyweight, all surgical sites are checked for hemostasis prior to routine abdominal closure Laparotomy: midline.

Aftercare

Immediate Aftercare

Potential complications

  • Patients  should be closely monitored for evidence of hemorrhage. Hemorrhage is the most commonly reported complication following liver lobectomy in human and canine patients; it has also been reported in cats following lobectomy but the numbers reported are too small for meaningful analysis.
  • If hepatic dysfunction exists, drug metabolism may be different to normal so discretion should be exercised with regard to dose and dose interval.
  • Continue intravenous fluid therapy until oral nutritional intake resumes.
  • Monitor renal function.

Outcomes

Complications

  • The literature regarding feline liver lobectomy is sparse, but reported complications have been similar to those seen in canine patients.
  • Bile peritonitis Peritonitis  Peritoneal fluid: bile from leakage of incompletely occluded biliary vessels or iatrogenic trauma to the biliary tree during dissection/lobectomy.
  • Liver abscess is a potential but very rare complication.
  • In cats it seems that benign liver masses, eg cystadenoma may be slightly more common than malignant tumors, eg bile duct carcinoma. Prognosis following resection of a discrete liver mass via lobectomy will depend on the primary disease.
  • Hepatic abscesses are uncommon in cats, but the available evidence suggests they are associated with significant mortality (79% in one study).

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Pavia P R, Kovak-McClaren J & Lamb K (2014) Outcome following liver lobectomy using thoracoabdominal staplers in cats. JSAP 55 (1), 22-27 PubMed.
  • Sergeeff J S, Armstrong P J, Bunch S E (2004) Hepatic abscesses in cats: 14 cases (1985-2002). JVIM 18 (3), 295-300 PubMed.
  • Trout N J, Berg R J, McMillan M C et al (1995) Surgical treatment of hepatobiliary cystadenomas in cats - five cases (1988-1993). JAVMA 206 (4), 505-507 PubMed.
  • Lawrence H J, Erb H N, Harvey H J (1994) Nonlymphomatous hepatobiliary masses in cats - 41 cases (1972 to 1991). Vet Surg 23 (5), 365-368 PubMed.

Other sources of information

  • McClaran J K & Buote N J (2014) Liver and Biliary tract. In: Feline Soft Tissue and General Surgery. Langley-Hobbs S J, Demetriou J L & Ladlow J F (eds), Saunders, Elsevier. pp 345-359.