109. Ovary and Uterus Flashcards
anatomy of the ovary
capsule –tunica albuginea (covered by peritoneum)ovarian bursa–double fold of peritoneum, blocked during ovulation by fimbriae of the infundibulumcortex—contains folliclesmesovarium from which arises the suspensory ligament and continuous with proper ligament and round ligament (passes thru inguinal canal)mesometrium/broad ligament
vascular supply to the ovary
–ovarian arteries from aorta–ovarian vein (R—VC, L–left renal vein)
what marks the junction of the peritoneum (mesosalpinx) with the mucus membrane lining of the uterine tube
fimbriae of the infundibulum near the opening of the ovarian bursaopening of the uterine tube into the uterine horn is called uterine osmium (tubulouterine junction–sphincter for passage of sperm and blastocysts)
layers or tunics of the uterus
–serosa–muscularis (myometrium)–smooth muscle inner thick circular, outter thing longitudinal –mucosa (endometrium)***thickest consists of epithelial cells that are occasionally ciliated and simple branched tubular glands
difference in dog vs cat cervix
dogs—diagonal across uterovaginal jxn (internal faces dorsal)cats—lies horizontal
vascular supply to the uterus
uterine arteries (branch of vaginal artery) anastomose with ovarian arteries
typical cycle stages and hormone release
–anestrus (low P, LH but E slowly climbs up)–proestrus (peak E, slow climb P during late proestrus, LH surge right before estrus/ovulation)–estrus (LH and E come back down, steady increase P) **cornified epithelial cells–metestrus/diestrus (steady decrease in P if no pregnancy or stays elevated if pregnant) 21-28 days of the ovarian cyclecats have a fifth stage of NONestrus during non cycling periods
difference in ovulation dogs vs cats
cats—induced (not dependent on E) ovulators (the formation of CL requires induced ovulation and the CL stays functional for 37 days)dogs—spontaneous ovulates (dependent on E) and then P maintains CL for 60-100 d in non pregnant bitches before it regresses
gestational length in bitches
57-72 days from first mating64 days from ovulation64-66 days from LH surge*accurate65 days +/- 3 days from P levels >1.5 ng/ml
detecting a fetal skeleton on radiographs
DAY 42 (or ~ 20 days before birth)
minimum data base abnormalities of a pregnant bitch
–normochromic anemia—hemodilution by increased plasma volume–mild leukocytosis, hypercholesterolemia, hyperproteinemia–HYPERGLYCEMIA from insulin resistance
signs of impending parturition
- < 2-3 ng/ml P 18-30 hr before giving birth2. temp drops <99-100 F 10-14 hr before giving birth (unreliable in cats)3. transcutaneous whelping monitors
three stages of parturition
I. nonvisable uterine contractions, nesting behavior–24 hrII and III. alternate as each fetus (II) and placenta (III) are passed; active uterine contractions presentlasts up to 36 hrsafter whelping, uterus involutes, lochia (odorless green brown hemorrhagic discharge) 4-6 weeks or longer
signs of distress during parturition
though normal pregnancy can take up to 36 hrs….dystocia should be considered if……1. lack of progression from stage I to II within 12-24 hrs2. active abdominal straining > 30 min b4 a puppy is seen3. time lag btwn puppies should not > 4 hrs4. failure to deliver pups within 36 hr5. lochia without delivery6. obstructed birth canal/fetal malposition on digital examination7. lack of Ferguson’s reflex (massage cervix and release endogenous oxytocin)8. signs of toxemia/systemic illness
time btwn first and last kittens was less the 6 hours in how many parturitions
86%(quicker than in dogs)
benefits of sterilization
- counteracts overpopulation2. decreases the likelihood of an animal being relinquished 3. may correct sexually dimorphic aggression (aggression btwn male and females in a house; NOT resolve nonsexual dimorphic behaviors)4. reduces the risk of mammary neoplasia 5. reduces the risk of pyometra and other uterine/ovarian diseases
incidence of pyometra in dogs
25% of intact bitches require treatment for pyometra by 10 yrs of agehormonal changes (diestrus) lead to cystic endometrial hyperplasia and secondary infxn (usually under P which stimulates gland secretion, suppresses uterine contraction and decreases ability of mononuclear cells to proliferate which dampens the immune response)ECOLItx with surgery OHE led to excellent px and survival in > 90%; peritonitis present 70% (with drains)
tumor types and diseases that have been overrepresented in gonadectomized animals
–TCC–OSA–HSA–Diabetes mellitus (cats)–Hypothyroidism (female dogs)–OBESTITY/decr metabolic rate (most common reported factor)–USMI (female—20% spayed dogs; multifactorial dz)–UTI (female dogs)–CCLR?
risks of timing of OHE to early
traditionally 6-9 mo (others 4 mo/after immunizations)shelters 6-16 weeks: riskS1. severe hypothermia— incr SA:V and less fat/vasoconstrictive reflexes, shaving/solutions2. hypoglycemia–inadequate liver stores and fx; avoid prolong fasting, give dextrose fluids3. immature liver/kidney fx–lack p450 enzymes in liver, leading to higher unbound drugs in circulation, risk side effects–need lower doses; inadequate kidney fx and low USG; inadequate RAAS system–prone to NSAID side effects4. incr demand on heart–avoid antichoinergicsIF appropriate surgery and anesthesia, prepubertal OHE does NOT carry incr risk
T/Fanticholinergics are recommended in pediatrics
FALSEdo NOT use anticholinergics in pediatric animals bcthey lack vagal tone and brady cardia may actually be more indicative of hypoxia (supplement oxygen)neonates (< 3weeks) may benefit from anticholinergics bc CO is more related to HR
T/Fprepubertal OHE is associated with incr MM
FALSE—not if good measures and considerations are performedIF appropriate surgery and anesthesia, prepubertal OHE does NOT carry incr riskdogs spayed at >2 yr had incr risk bc incr BW and int surgery timelong term effects of spay are independent of spay timing (no difference if spayed 7 mo vs 7 wk)
incidence of perioperative complications following OHE
12 % cats19% dogs(< 20%)—incisional, hemorrhage (<3%), infection, etc**surgery time significantly associated with occurrence of complications
hemorrhage as a complication of OHE in dogs
~3%in dogs weighing > 25 kg , hemorrhage was the most common complicationhemorrhage was the most common cause of death after OHE in large dogsmay come from: perirenal capsule, incomplete ligations around pedicles, and loose ligatures around pedicles
methods to decrease risk hemorrhage
—strum suspensory ligament lateral to medial–avoid perirenal capsule when applying traction–correctly ID mesovarium from mesometrium to ligate appropriate ovarian pedicle—tight ligations, surgeons throw (based on TJ) and FLASH
Trendelenburg position
15 degrees head down for laparoscopy
methods for ligation during laparoscopic OE
- bipolar sealing device2. US harmonic scalpel/sealing device3. pretied loop ligature4. extracorporeal suture (and knot pusher)5. hemoclips6. electrocauterysealing devices have been associated wit bless hemorrhage and a shorter surgery time
uterine pressures after stump sealing with bipolar sealing device
300 mm Hg
T/Flong term studies have failed to show significant advantage of OHE vs OE alone unless the uterus has pathologic changes
trueno diff in OE vs OHE (as long as full ovary is removed, P is gone and pyometra should not occur unless exogenously administered)urinary incontinence and obesity are not significantly different for OHE vs OE
ovarian remnant syndrome
– low LH indicates ovarian remnant bc spayed dogs have hi LHor–persistent hi E (> 15 pg/ml) and P (>2ng/ml)–vaginal cytology: cornified epithelium (>80%) indicates estrus (ddx: functional neoplasia, ovarian remnant, functional cysts)–cats are overrepresented 63%
ovarian neoplasia
originate from germ cells, epithelial cells, or sex cord stromal cellsmets is uncommontransabdominal seeding risk—-DO NOT RECOMMEND ASPIRATION or NEEDLE BIOPSY of ovary
type of ovarian tumor seen on rads as space occupying mass caudal to kidney with calcification
teratoma
most common sex cord tumor of the ovary
granulosa cell tumor (50% of ovarian tumors)–produce E, P, or both–20% metestrogen may cause bone marrow suppression/aplasia and possibly irreversible pancytopeniaotherwise goo prognosis if single mass, no mets and surgically removed
ovarian cysts
–functional (ovarian) or nonfunctional (incidental–periovarian)–functional cysts are lined with granulosa cells and secrete E +/- P–10-50 mm big vs 4-10 mm big preovulatory follicle –med mgmt with GnRH if valuable bitch–ovariectomy is curative
true hermaphrodite chimera
XX/XY or XX/XXXY chromosomemay have testicular and ovarian tissue in seperate or the same gonadal structure female external appearance and a large clitoris or hypoplastic penisfail to exhibit estrus or a complete ovarian cyclevulvar pruritis bc of protruding clitoral tissue
clinical signs of pyometra
–polyuria 70% (potential glomerular damage)—vaginal discharge 50-85%–SIRS 50-60%–high WBC, w regen left shift, hypo alb, elevations in liver enzymes, thrombocytopenia–high protein C (incr morbidity as indicated by incr hospital stay)
T/FDO NOT OVERSEW UTERINE STUMP OF PYOMETRA
TRUE
indications for medical mgmt of pyometra
–high breeding value–NOT systemically ill–OPEN cervix and drainingPGF2 alpha causes myometrium contraction and relaxation of the cervix (but 48 hr lag time)—systemic and local therapy reportedsystemic AB+/- transcervical uterine cannulationunknown recurrence
primary clinical sign of cystic endometrial hyperplasia
failure to conceive
differenitials for enlarged fluid filled/mixed echogenicity uterus
—cystic endometrial hyperplasia—hydrometra–pyometra–mucometra–hematometriasignalment, history, clinical signs, bloodwork may help ddx
at what stage of the ovarian cycle does metritis occur
metritis—post partumpyometra–diestrusboth cause systemic illnessvaginal smears are NOT diagnosticfoul smelling vaginal dischargeculture and ABsurgery if retained fetus/placenta (hysterotomy or OHE)
antibiotics safe for pregnant or nursing bitches
penicillinserythromycincephalosporinsclindamycin
dystocia pathophysiology
maternal causes (75%): PRIMARY uterine inertia, small pelvic canal or pelvic malunionfetal causes (25%): malpositioned fetus, fetal malformation, oversize causes of primary uterine inertia: low oxytocin, large litter overstretch, small litter under stimulate, hypoCa, low prostaglandin metabolites, poor nutrition
fetal HR
normal fetal HR 220- bpmif 150-180 bpm in awake dam, SEVERE FETAL DISTRESS
medical mgmt of dystocia
–oxytocin after making sure bloodworm was normalCONTRAINDICATED IF…1. obstruction palpated2. fetal stress3. abdominal contracts > 30 minutes without puppy 4. failed 2 doses of oxytocin
of bitches with dystocia, how many need a c section
60-65%regional anesthesia or GA w/o premed, propofol induction, light isoflurane, atropine if fetal HR is low surgery options:–OHE enbloc (fetuses should be removed within 60 sec)–hysterotomy, fetus removal, OHE–hysterotomysurvival bitches 99% and neonates 87% (brachycephalics had lower survival rates)
neonatal rescucitation
- clear fluid from oral cavity/nostrils with suction2. vigorously rub to stimulate respiration3. DO NOT SWING (intracerebral hemorrhage)4. reverse any opiates (naloxone)5. O2 supplement (face make, intubation)6. NO ANTICHOLINERGICS (may increase oxygen demand)can give epinephrine through umbilical vein7. doxapram respiratory stimulant is no longer indicated bc increases myocardial oxygen consumption and is ineffective if hyperemic8. dried and warmed9. clean mother teats from antiseptic solution prior to nursing
T/FOHE does not influence milk production
TRUEOHE does not influence milk production
most common uterine tumors in dogs vs cats
dogs mesenchymal tumorsleiomyomas 90% leimyosarcomas 10%excellent prognosis cats endometrial originadenocarcinomas–mets commongaurded prognosis
birt-hogg-dube gene
GSD–hereditary mutationnodular dermatofibrosismultiple uterine leiomyomasrenal cystadenocarcinoma
congenital abnormality of the uterus
uterus unicornisaplasia, hypoplasia, segmental aplasia. double cervix etccan be associated with kidney agenesis
