Urogenital Surgery Flashcards
What is an ovariohysterectomy?
surgical removal of the ovaries and uterus
- entire uterine body removed in dogs in US and UK
What is an ovariectomy?
a quicker laparoscopic procedure for the removal of the ovaries
- countries other than US and UK, no long-term differences in outcome compared to OVH
What are 6 indications for ovariectomies/ovariohysterectomies
- elective sterilization
- ovarian or uterine disease
- prevent mammary neoplasia
- part of control of some diseases
- prevent recurrence of vaginal hyperplasia and prolapse
- eliminate recurrent pseudocyesis
What are 3 purposes of elective sterilization?
- decrease overpopulation
- decrease incidence of hereditary defects
- moke animal a more desirable pet
What is the top ovarian/uterine disease that OVH treat? What are 5 others?
pyometra and metritis (treating medically is questionable, likely to come back due to hormones)
- uterine torsion
- neoplasia of ovary or uterus
- uterine prolapse
- paraovarian cysts
- trauma
How can mammary tumors be prevented with OVH?
significant effect if done before first estrus in dogs and cats
What 2 secondary conditions can be controlled by OVH? How?
- idiopathic epilepsy
- diabetes mellitus
hormones and heat cycle decrease seizure threshold and affect metabolism
What are 3 advantages to early OVH? What is required before surgery?
- significant decrease in incidence of mammary neoplasia
- no risk of unwanted pregnancy
- surgical procedure is technically easy
complete vaccination
When is it too early to perform an OVH? Why? What are 3 disadvantages
< 3 months —> decreased hormones needed for proper growth
- juvenile vulva possibly leading to perivulvar dermatitis
- increased incidence of incontinence in dogs
- anesthetic challenge in small patients
What minimum pre-anesthetic evaluations are necessary before OVH?
- PE with careful cardiac auscultation
- hematology and serum biochemistry
What are 9 complications associated with OVH?
- hemorrhage
- dehiscence of abdominal incision
- ligation of ureter
- recurrent estrus
- uterine stump pyometra
- uterine/ovarian stump granuloma
- estrogen-sensitive urinary incontinence
- obesity
- perivulvar dermatitis
What is the most common fatal complication associated with OVH? What is it caused by? How is it treated?
hemorrhage (ovarian arteries arise directly from aorta!)
inadequate ligation of pedicles
religate vessels
What are the 3 most common clinical signs associated with post-OVH hemorrhage?
- pale from blood loss or peripheral vasoconstriction due to hypothermia
- prolonged CRT*
- normal PCV due to surgical fluids —> used for trends
When is vaginal hemorrhage most commonly seen post-OVH? What is it caused by? Treated?
4-16 days after —> slight bleeding within 12-24 hours is normal
erosion of uterine vessels associated with ligature
re-explore the abdomen and religate vessels individually
What are the 2 most common causes of abdominal incision dehiscence? Clinical signs? How is it treated?
- failure to close linea alba
- failure to restrict exercise following surgery
non-painful swelling
lavage of abdomen, debridement, and closure of incision
What are the most common clinical signs of ureter ligation? In what 3 ways can this avoided?
none if unilateral; anuric if bilateral
- careful identification of uterus before ligating
- emptying the urinary bladder
- not grasping blindly into a pool of blood to retrieve ovarian pedicles
How can a ligated ureter be treated?
- remove ligature
- nephroureterectomy
What can cause recurrent estrus following an OVH? How is it treated?
failure to remove all ovarian tissue by technical error or ectopic
re-explore while in heat when the tissue will be swollen and enlarged so the ovarian tissue can be removed
- no tissue identified = resect both ovarian stumps
What is the most common cause of uterine stump pyometra? Most common clinical signs?
break of aseptic technique with ligature too far apart on uterine pedicle
- LUT disease signs due to inflamed tissue
- fever
How is uterine stump pyometra treated?
surgical removal of remaining uterine tisue
- metritis due to contamination
What are 2 causes of uterine/ovarian stump granuloma? In what animals is it most common?
- multifilament nonabsorbable sutre material used for ligatures (fistula!)
- imperfect aseptic technique or excessive devitalized tissue in stump
dogs > cats
What are 2 complications associated with uterine/ovarian stump granulomas?
- chronic inflammatory granuloma develops at stump and may progress to fistula in flank
- granuloma may damage urinary bladder, colon, ureters, or kidneys
How can uterine/ovarian stump granulomas be prevented? How are they treated?
using absorbable suture material for ligatures
resection of all stumps plus reconstructive procedures —> partial cystectomy, partial nephrectomy, reimplantation of ureters, colonic resections/anastomosis
How does loss of estrogen cause urinary incontinence? What causes increased incidences? How is it treated?
estrogen decreases the threshold of response to alpha agonists
when OVH is performed before 3 months of age
alpha agonist (PPA) or estrogen (DES)
How does OVH affect BCS?
may adversely affect dog’s ability to regulate food intake —> decrease caloric intake and increase exercise
What is perivulvar dermatitis caused by? How is it treated?
recessed, infantile vulva and perivulvar folds secondary to obesity result in the accumulation of urine in the perivulvar area
- episioplasty: vulvoplasty removes redundant tissue
- weight reduction*
In what animals is a prolapsed uterus most common? When does it most commonly occur?
cats
following parturition
How is a prolapsed uterus treated?
- lavage with hypertonic solution to decrease swelling and assess tissue vitality
- good condition = manual reduction
- devitalized or irreducible = reduction and OVH
What is pyometra?
potentially life-threatening accumulation of purulent material in the uterus associated with cystic endometrial hyperplasia
What are the 5 most common bacterial causes of pyometra?
- E. coli
- Staphylococcus intermedius
- Streptococcus
- Pseudomonas
- Proteus
What increases the risk of developing pyometra?
increased number of non-gravid estrus cycles (progesterone!) —> act of pregnancy clears the uterus
What is the most common signalment associated with pyometra?
- dogs > cats
- middle-aged to older
- dogs of any age that have been given exogenous estrogen or progestins (mismating shots)
How does pyometra develop? What are the 2 types?
gradually after estrus or hormone administration
- OPEN - vaginal d/c, less clinical
- CLOSED - vomiting, diarrhea, fever, anorexia, PU/PD, abdominal distension, collapse, death (becomes septic!)
What 7 laboratory abnormalities are associated with pyometra?
- elevated WBC with absolute neutrophilia and left shift, progressing to degenerative left shift and neutropenia
- hyperproteinemia, hyperglobulinemia
- anemia - normocytic, normochromic, regenerative
- azotemia
- isosthenuria, proteinuria, bacteriuria (no cystocentesis!)
- hypoglycemia
- coagulopathy, hepatic dysfunction, cardiac arrhythmias
What is seen on radiography and ultrasonography in patients with pyometra?
fluid-filled uterus —> cannot be differentiated from hydrometra or mucometra
(no evidence of pregnancy)
When is medical treatment used for patients with pyometra? What 3 treatments are used?
open pyometra in valuable breeding animals
- prostaglandin or aglepristone + cloprostenol
- antibiotics
- breeding - must become pregnant at next cycle, or it will recur
What surgical treatment is recommended in patients with pyometra? How is the patient prepared before?
OVH
- IV antibiotics and fluids, treat shock if present
- DON’T delay surgery more than a few hours needed to correct dehydration, electrolyte imbalances, or anemia
How is the OVH used to treat pyometra different than usual?
- generous ventral midline approach and packing off of the cavity
- especially important to avoid rupture
- invert uterine stump or paint exposed endometrium with antiseptic solution
Where are the ovaries located? Uterine horns? Uterine body?
caudal pole of kidneys
dorsolateral in body cavity
between urinary bladder and colon, adjacent to ureters
Where are the vessels supplying the ovaries and uterus found? What is seen in dogs?
mesovarium and mesometrium
fat within ovarian bursa, mesovarium, and mesometrium can obscure vessels
What approach is used for OVH? What should be done if the uterus is distended? What should be avoided?
ventral midline —> umbilicus to 2-4 cm to pubis
enlarge incision to the pubis (avoid keyhole incisions)
How are the ovaries elevated? How are you able to manipulate them?
tearing the suspensory ligament
clamping the proper ligament
How are ovarian pedicles ligated?
3 clamp technique
- 3 forceps are placed through an opening in the mesovarium
- the most distal clamps are located proximal to the ovary
- circumferential ligature placed in the crush of the proximal clamp
- second ligature placed distal to the first while the second clamp is flashed on the first 2 throws, then closed again
- tissue transected between the middle and distal clamps
What may have to be done in the mesometrium of fat dogs?
ligation of uterine vessels before the mesometrium is cut/torn
How is the uterine body ligated in dogs and cats?
3 clamp technique —> Rochester-Carmalts
- DOGS: ligated and transected directly cranial to the cervix between the distal and middle forceps
- CATS: ligated and transected around the caudal 1/3 of the uterine body, since there is no obvious cervix
What is done after the ovaries and uterus is removed?
- pedicles are observed for bleeders using the mesoduodenum and mesocolon to retract abdominal contents
- check for loose sponges —> RFID tags!
- check ureters
- abdominal incision is closed
When is the use of hemoclips for ligation especially helpful?
young or small patients
What post-operative care is most important with OVH?
- exercise restriction
- prevent self-mutilation with E-collars
- isolate patients in estrus, since mating in early post-op period can cause severe abdominal bleeding or peritonitis
- pain control
What should be monitored for following OVH for pyometra treatment ? How long are fluids given? What are antibiotics based on?
shock, sepsis, and fluid/electrolyte abnormalities 24-48 hours post
until the animal is eating, drinking, and maintaining hydration
based on culture and sensitivity (10-14 days)
What is prognosis of pyometra like? What sign commonly takes longer for improvement?
good if complications of shock, sepsis, and renal damage are avoided
anemia —> monitor PCV for several weeks
What is a Caesarian section? What are 5 indications?
hysterotomy —> surgically opening of the gravid uterus to remove feti
- dystocia
- fetal death +/- putrefaction
- uterine rupture
- maternal toxemia
- prolonged gestation (72+ hr past due date)
What 4 pre-operative evaluations are done before Caesarian sections?
- PE
- rectal and sterile vaginal exam
- abdominal radiographs
- blood glucose and calcium
When is oxytocin administered for Caesarian sections?
ONLY if the cervix is dilated —> induces uterine contractions!
What are 3 important aspects of the anesthetic protocol in Caesarian sections?
- epidural anesthesia alone is not sufficient
- intubation
- use of sedative/anesthetic drugs that can be reversed in neonates
Where is the hysterotomy incision made in Caesarian sections? What is done next?
in the body of the uterus —> avoid cutting fetus or placenta!
- fetus removed by gentle traction with placental separation
- fetus handed off to non-sterile assistant
- milk remaining feti down to uterine incision
How is hemorrhage at placental attachment sites controlled?
- direct pressure
- oxytocin IM into uterus
How is the uterus closed following Caesarian section? When is the peritoneal cavity lavaged?
1 or 2 layers with absorbable suture
if spillage occurred
What is an en bloc Caesarian section?
spay with puppies inside —> clamp all pedicles, excise ovaries and uterus quickly (30-60 seconds) and handed off to a non-sterile assistant with will open the uterus if fetal survival is desired
What 3 complications are associated with Caesarian sections? How are they treated/prevented?
- hypovolemia/hypotension - IV fluids
- uterine hemorrhage - direct pressure, oxytocin
- peritonitis - avoid spillage
How are neonates cared for following Caesarian sections?
- remove amniotic sac
- remove fluid from oral and nasal cavities with bulb syringe or swab
- stimulate respiration by rubbing and swinging or using sublingual Doxapram
- ligate and divide umbilical cord
- reverse narcotics with naloxone
- keep warm and place with mother ASAP
What is uterine agenesis?
poor formation or lack of development of a side of the reproductive tract
What is indicative of ovarian remnant syndrome? What are 3 factors that increase risk?
signs of estrus following an OVH
- inadequate incision length
- poor exposure
- failure to examine the ovaries after removal
How is vaginal hyperplasia treated?
- OVH = involution
- episiotomy (avoid urethral papilla by placing a catheter)
(=/= prolapse, has no lumen, hyperplasia caused by hormone imbalance)
What are transmissible venereal tumors?
tumors of viral origin commonly found in the prepuce of Southern, feral dogs that can be transmitted to females upon mating —> looks like vaginal hyperplasia
(tx = vincristine, sx removal)
