Ovaries and uterus Flashcards
In a study by Adams 2022 in Vet Surg, were puppies delivered by emergency or elective caesarian more likely to survive?
Elective caesarian. No difference in survival between brachycephalic and non-brachycephalic breeds.
In a study by Pailler 2022 in JAVMA, what were 3 factors associated with a higher risk of uterine rupture in queens with pyometra? What was overall survival to discharge?
Increased rectal temperature, closed pyometra, or heart murmur.
100% survival to discharge was reported in this study.
According to Benka 2023 in JAVMA, did gonadectomy increase the risk of developing an overweight or obese body condition score in dogs? Was the risk greater for males or females?
Yes an increased risk was observed. This risk was greater for males, and tended to be increased in patients sterilized after 1 year of age.
In a study by Guest 2023 in JAVMA, was concurrent ovariohysterectomy at the time of caesarian associated with an increased risk of mortality, intra- or post-operative complications, or decreased mothering ability?
No - concurrent OVH was not associated with any of these issues. Only difference was an increased perception of post-operative pain as per the owners.
In a study by Owen 2023 in JAVMA, was laparoscopic assisted ovary sparing hysterectomy associated with an increased risk of stump pyometra compared to OVE?
No - there was no increased risk observed.
In a study by Bruckner 2024 in JAVMA, were there any benefits to lap-assisted OVH compared to open OVH for treatment of pyometra?
No benefits observed, although LapOVH took longer.
In a study by Pegram 2019 in JSAP, what 3 factors increased the incidence of urinary incontinence in bitches? What factor was not correlated with urinary incontinence?
In a second study by the same author, what 4 risk factors were identified as risk factors for early onset urinary incontinence (<8 years)?
Spaying and increasing age and bodyweight.
Age of spay was not associated with an increased risk of incontinence.
In a second study spey, age at spay (<6 months), increasing age and bodyweight were all associated with increased risk of early onset incontinence.
In a study by Demeli 2023 in JSAP, what 5 CBC/biochem parameters were increased with pyometra, what 3 parameters were reduced?
Increased: leukocytes, monocytes, AST, ALP, BUN.
Decreased: HCT, hemoglobin, albumin.
In a study by Nilsson 2023 in VRU, what percentage of dogs had free peritoneal fluid on post-operative ultrasound at 1, 4-6, and 10-15 days post-surgery for pyometra?
45%, 41%, and 9%.
Presence of pneumoperitoneum was detected in 95%, 82%, and 14% of dogs at the same time points.
In a study by Fudge 2021 in JFMS, did pregnant or non-pregnant cats have higher blood loss during OHE?
Pregnant cats had higher blood loss. They were also relatively hypercoaguable and had an increased rate of clot lysis, although no clinically relevant bleeding conditions occurred.
In a study by Maniaki 2021 in JFMS, did neutering/spaying cats before 6 months of age result in an increase of owner reported mobility changes at 6 years of age? What 3 other risk factors for decreased mobility were identified?
No neutering/spaying before 6 months of age actually reduced the risk of mobility changes.
Outdoor, overweight cats with a history of trauma were at an increased risk of mobility issues.
In a study by Bailin 2022 in JFMS, in what percentage of cats presenting to an emergency service was dystocia related to maternal v. fetal factors? In what percentage of cats was medical management of dystocia successful? What percentage of queens and neonates survived to discharge?
Maternal factors were responsible for 69% of dystocias, and fetal factors were responsible for 31%. No queens were hypoglycemic or hypocalcemic.
Medical management was successful in 29% of cases.
Maternal survival was 94%. Neonatal survival was 66%. Surgically delivered neonates had the lowest survival rates (50%, compared to 64% for medical management).
In a study by Flock 2022 in JFMS, was anti-mullerian hormone a useful tool for detection of ovarian remnant syndrome in queens?
Yes, could be used to differentiate between spayed and cats with ovarian remnant syndrome. This was regardless of the hormonal activity of the remnant ovarian tissue.
What is the capsule of the ovary called?
Tunica albuginea
What structures constitute the broad ligament?
Mesovarium and mesometrium.
What is the arterial supply to the ovaries?
The paired ovarian arteries, arise from the aorta cranial to the deep circumflex iliac arteries and caudal to the renal arteries.
What is the venous drainage of the ovaries?
Right ovarian vein: caudal vena cava.
Left ovarian vein: left renal vein.
Both veins anastomose with the uterine veins.
What is the lymphatic drainage of the ovaries?
Lumbar lymph nodes.
What is the opening of the uterine tube into the uterine horn called?
Uterine ostium.
What is located at the ovarian end of the uterine tube?
Infundibulum fringed with fimbriae.
What are the three layers of the uterus?
Serosa, muscularis (myometrium), mucosa (endometrium). Endometrium is the thickest of the three.
The myometrium has a thick inner circular layer and thin outer longitudinal layer.
What is the difference in cervical position between dogs and cats?
Dogs: diagonally positioned with the external orifice positioned toward the vaginal floor.
Cat: relatively horizontal.
What is the vascular supply to the uterus?
Anastomosing blood supply from the ovarian and uterine arteries. The uterine artery is a branch of the vaginal artery.
Uterine veins follow the arteries.
What is the lymphatic drainage of the uterus?
Hypogastric and lumbar lymph nodes.
What are the four phases of the estrus cycle?
Proestrus, estrus, diestrus, anestrus. The feline cycle has a fifth ‘nonestrus’ phase during non-cycling periods.
What are the main differences in ovulation between the dog and cat?
Cats are induced ovulators. Following ovulation they have progesterone dominance (functional corpus luteum) for 37 days.
Dogs ovulate spontaneously and have progesterone dominance for 60-100 days.
What is the gestational length of dogs and cats?
Dogs: 64 days
Cats: 66 days
What are methods to measure gestational length/stage in the dog?
- Accurate when measured from progesterone elevation >1.5 ng/mL.
- Ultrasound (before day 39 of pregnancy).
- Measured from luteinizing hormone peak.
When do canine fetal skeletons become visible on radiographs?
42 days, fetal pelvises by day 57.
When are canine fetal heartbeats detectable on ultrasound?
1-2 days after implantation of blastocysts on the uterine wall (day 21-22).
What are some bloodwork changes seen in the pregnant bitch?
CBC: normocytic normochromic anemia due to hemodilution (PCV <40% @ day 35, <35% at term).
Biochem: leukocytosis, hypercholesterolemia, hyperproteinemia, increased protein C and fibrinogen +/- hyperglycemia (insulin resistance).
What progresterone changes are observed in the bitch just prior to parturition?
Sudden drop in progesterone (<2-3 ng/mL) occurs 18-30 hours prior to parturition. This is typically followed by a fall in body temperature (<37.2-37.8 degrees) 10-14 hours later.
What are the three stages of parturition in the bitch?
Stage 1: externally nonvisible uterine contractions (can last up to 24 hours). Bitch appears restless, exhibits nesting behaviours.
Stage 2: expulsion of the fetus.
Stage 3 (alternating with stage 2): expulsion of the placenta.
Duration of stages 2 and 3 can last up to 36 hours, but active straining should not exceed 30 minutes, and time lag between puppies should not exceed 4 hours.
What is lochia?
An odorlous green, dark red-brown or hemorrhagic vaginal discharge associated with uterine involution. Can last for 4-6 weeks.
How can gestation length of queens be determined?
- Measured from the rise in progesterone >2.5 ng/mL.
- Ultrasound
When is mineralization of feline fetuses observed?
Day 25-29 post parturition (1 week earlier than dogs).
When does trophoblastic attachment occur in the queen?
Day 15
What are some bloodwork changes typically seen in pregnant queens?
Anemia (20% reduction in hematocrit).
Is temperature drop an accurate indicator of impending parturition in cats?
No
What is the typical time taken between the first and last kitten in queens?
6 hours, although some queens will act as though parturition has finished for up to 48 hours before recommencement (<1% litters).
What are some health problems related to ovariohysterectomy?
Neoplasia: osteosarcoma more common in Rottweilers spayed < 1 year of age, spayed Vizslas have an increased risk of mast cell or hemangiosarcoma.
Endocrine: increased risk of diabetes mellitus in cats and hypothryoidism in dogs.
Weight: obesity is 2 x more likely in spayed female dogs.
Urinary: urethral sphincter mechanism incontinence reported in up to 20% of spayed bitches. Larger dogs (15 kg) 7 x as likely to develop this condition.
What are some physiologic considerations when performing prepubertal OHE?
Pediatric animals have an immature hepatic and renal function, increased risk of hypothermia and hypoglycemia, and greater reliance on heart rate for cardiac output.
Fasting should be limited to <4 hours, glucose supplementation may be required, active warming is essential.
Judicious use of drugs required and at lower doses (underdeveloped microsomal P-450 enzyme activity prior to 4.5 months and lower plasma protein concentrations = higher fraction of unbound drugs).
RAAS does not become functional before 6 weeks and therefore renal bloodflow is entirely dependent on arterial blood pressure. Care with fluid administration required.
Anticholinergics may be required to maintain cardiac output. If nonresponsive may be due to hypoxemia and O2 supplementation should be administered.
Is prepubertal OHE associated with an increased risk of complications?
No - dogs older than 2 years of age, with increasing body weight and surgical time associated with higher short-term complications.
What size uterine body can vessel sealing devices safely ligate?
9mm (low mean bursting pressure observed for uterine bodies sealed >9mm).
What are some diagnostic criteria that indicate primary uterine inertia that may benefit from medical management?
What are some diagnostic criteria for dystocia that indicate need for immediate caesarean section?
