Veterinary Surgery

Veterinary Surgery

Specialization in surgery
 
In the United States and Europe, veterinary surgery is one of 20 veterinary specialties recognized by the American Veterinary Medical Association respectively the European Board of Veterinary Specialisation. Those wishing to become board certified must undergo three years of intensive training in a residency program under direct supervision of Board Certified Veterinary Surgeons, including performance of a large number of surgical procedures in such categories as abdominal surgery, surgical treatment of angular limb deformities, arthroscopic surgery, surgery of the foot, fracture fixation, ophthalmic surgery, urogenital surgery, and upper respiratory surgery, etc. Once the minimum requirements of training are met residents are required to pass a rigorous certification examination before being admitted as members (Diplomates) of the American College of Veterinary Surgeons or European College of Veterinary Surgery.
 
 
Veterinary anesthesia
 
Anesthesia in animals has many similarities to human anesthesia, but some differences as well. Local anesthesia is primarily used for wound closure and removal of small tumors. Lidocaine, mepivacaine, and bupivacaine are the most commonly used local anesthetics used in veterinary medicine. Sedation without general anesthesia is used for more involved procedures. Sedatives commonly used include acepromazine, hydromorphine, midazolam, diazepam, xylazine, and medetomidine. α2 agonists like xylazine and medetomidine are especially useful because they can be reversed, xylazine by yohimbine and medetomidine by atipamezole. Xylazine is approved for use in dogs, cats, horses, deer, and elk in the United States, while medetomidine is only approved for dogs. Most surgeries in ruminants can be performed with regional anesthesia.
 
General anesthesia is commonly used in animals for major surgery. Animals are often premedicated intravenously or intramuscularly with a sedative, analgesic, and anticholinergic agent (dogs frequently receive buprenorphine, acepromazine, and glycopyrrolate). The next step is induction, usually with an intravenous drug. Dogs and cats commonly receive thiopental (no longer allowed in the UK), ketamine with diazepam, tiletamine with zolazepam (usually just in cats), and/or propofol. Alfaxalone is a steroid anaesthetic used in many practices in the UK to induce anaesthesia in cats and sometimes dogs. It is similar in physiological effect but different in composition to the now withdrawn Saffan. Horses commonly receive thiopental and guaifenesin. Following induction, the animal is intubated with an endotracheal tube and maintained on a gas anesthetic. The most common gas anesthetics in use in veterinary medicine are isoflurane, enflurane, and halothane, although desflurane and sevoflurane are becoming more popular due to rapid induction and recovery.
 

Common veterinary surgeries

 
Elective procedures
 
One of the most common elective surgical procedures in animals is neutering. Neutering in animals describes spaying or castration (also please see castration). To spay (medical term: ovariectomy or ovario-hysterectomy) is to completely remove the ovaries and often the uterus of a female animal. In a dog this is accomplished through a ventral midline incision into the abdomen. In a cat this is accomplished either by a ventral midline abdomenal incision, or by a flank incision (more common in the UK). With an ovariectomy ligatures are placed on the blood vessels above and below the ovary and the organ is removed. With an ovariohysterectomy the ligaments of the uterus and ovaries are broken down and the blood vessels are ligated and both organs are removed. The body wall, subcutis, and skin are sutured. To castrate (medical term: orchidectomy) is to remove the testicles of a male animal. Different techniques are used depending on the type of animal, including ligation of the spermatic cord with suture material, placing a band around the cord, or crushing the cord with a Burdizzo.
 
 
Neutering is usually performed to prevent breeding or prevent unwanted behavior or future medical problems. Please see spaying and neutering for more information on the advantages and disadvantages of this procedure. Neutering is also performed as an emergency procedure to treat pyometra and testicular torsion, and it is used to treat ovarian, uterine, and testicular cancer. It is also recommended in cases of cryptorchidism to prevent torsion and malignant transformation of the testicles.
 
Other common elective surgical procedures in the USA are declawing in cats (onychectomy), ear-cropping in dogs, and tail docking in dogs and horses. These procedures are illegal in some countries (declawing is illegal and tail docking is only allowed in working dogs in the UK) and face ethical challenges in others. Declawing consists of removal of the distal phalanges using either a scalpel, scissors or laser.
 
Laser surgery offers a number of benefits, including reduced risk of infection, less post-operative pain and swelling, reduced bleeding and improved visibility of the surgical field. Better hemostasis and visibility can in some cases minimize the need for anesthesia and/or reduce overall surgical time.
 
Dental surgery
 
Common dental surgical procedures:
  • Horses - Floating (grinding down) of uneven teeth edges and removal of wolf teeth.
  • Dogs - Dental prophylaxis is commonly performed to remove tartar and treat periodontal disease. This procedure is usually performed under anesthesia. Other common procedures include extraction of abscessed or broken teeth, extraction of deciduous teeth, root canals, and removal of gingival hyperplasia and epulides.
  • Cats - Dental prophylaxis as described above for the dog and treatment and extraction of teeth with feline odontoclastic resorptive lesions (FORLs).

Surgical oncology
 
In older dogs and cats tumors are a common occurrence. Common skin tumors include lipomas, mast cell tumors, melanomas, squamous cell carcinomas, basal cell carcinomas, fibrosarcomas, and histiocytomas. Skin tumors are removed through either simple incisions or through plastic surgery. Common oral tumors include melanomas, fibrosarcomas, squamous cell carcinomas, which are removed with as much surrounding tissue as possible, including parts of the mandible and maxilla. Other types of cancer requiring surgery include osteosarcoma, stomach and intestinal tumors, splenic masses, and urinary bladder tumors.
 
Ophthalmic surgery
 
Common ophthalmic surgeries in animals include:
  • Enucleation of the eye to treat glaucoma or eye proptosis.
  • Cataract surgery
  • Entropion surgery
  • Ectropion surgery
  • Eyelid tumor removal
  • Cherry eye surgery
  • Exenteration (complete removal) of the orbit, especially for squamous cell carcinoma in the cat and cow.
Orthopedic surgery
 
Common orthopedic surgeries in animals include:
  • Ruptured anterior cruciate ligament repair
  • For hip dysplasia:
  • Femoral head ostectomy
  • Triple pelvic osteotomy
  • Hip replacement
  • Leg amputation
  • Bone fracture repair
  • Arthroscopy
  • MPL - medial patellar luxation
  • APL - anterior patellar luxation

Other common procedures

 
Caesarean section
 
Caesarean sections are commonly performed in dogs, cats, horses, sheep, and cattle. Usually it is done as an emergency surgery due to difficulties in the birthing process. Certain dog breeds such as Bulldogs often need to have this surgery because of the size of the puppy's head relative to the width of the bitch's birth canal.
 
Bloat surgery
 
In dogs bloat or gastric dilatation volvulus (GDV) is a common condition where the stomach fills with gas and commonly twists. If the stomach is torsed it requires immediate surgical intervention to prevent necrosis of the stomach wall. After radiographs to confirm the GDV and blood tests to determine the lactate and general health of the dog, surgical intervention is required. The stomach is put back into its normal position, deflated and tacked (gastropexy) to the body wall. Sometimes a splenectomy or partial gastrectomy is also required.
 
Cystotomy
 
A cystotomy is a surgical opening of the urinary bladder. It is commonly performed in dogs and cats to remove bladder stones or tumors.
 
 
Wound repair
 
Bite wounds from other animals (and rarely humans) are a common occurrence. Wounds from objects that the animal may step on or run into are also common. Usually these wounds are simple lacerations that can be easily cleaned and sutured, sometimes using a local anesthetic. Bite wounds, however, involve compressive and tensile forces in addition to shearing forces, and can cause separation of the skin from the underlying tissue and avulsion of underlying muscles. Deep puncture wounds are especially prone to infection. Deeper wounds are assessed under anesthesia and explored, lavaged, and debrided. Primary wound closure is used if all remaining tissue is healthy and free of contamination. Small puncture wounds may be left open, bandaged, and allowed to heal without surgery. A third alternative is delayed primary closure, which involves bandaging and reevaluation and surgery in three to five days.
 
 
Wounds occurring in the udder and teats of cows are more difficult to repair, due to the difficult access and sensitivity of the organ, and because deep anaesthesia may not be applied to bovines. But some practitioners have acquired a great experience in dealing them.
 
Foreign body removal
 
A variety of objects are commonly swallowed by dogs, cats, and cattle. Foreign bodies can cause obstruction of the gastrointestinal tract causing severe vomiting and resulting electrolyte imbalances. The stomach (gastrotomy) or intestine (enterotomy) can be surgically opened to remove the foreign body. Necrotic intestine can be removed (enterectomy) and repaired with intestinal anastomosis. Foreign bodies can also be removed by endoscopy. The condition in cattle is known as hardware disease.
  • Recommend Us