Obstetrics Flashcards
Physiological Changes in Pregnancy - CVS (4)
Cardiac output and plasma volume: increased 50%
Systemic vascular resistance: decreased
MAP unchanged or slightly lower.
Pregnancy increases intravascular volume.
Physiological Changes in Pregnancy - Respiratory (4)
Respiratory rate unchanged
Tidal volume increased
Minute ventilation increased
Ventilation exceeds needs
Describe the characteristics of patients that present with lichen sclerosis, and the natural history of the disease.
Usually in the post-menopausal period. Can occur at any age.
Itching worse at night. - vaginal itching.
Skin classically described as “cigarette paper” as it appears crinkled and is fragile, thinned and atrophic.
Scratching can lead to scarring causing narrowing or complete closure of the vaginal introitus. Labia minora may fuse burying the clitoris behind the fused clitoral hood.
Recognize the anatomical boundaries of the vulva and aspects of good vulvar
hygiene.
The anatomic boundaries of the vulva extend from the mons pubis superiorly to the anus inferiorly and the genitocrural folds laterally.
Avoid irritants such as soaps and bubble baths, cessation of scratching the lesions, and wearing all cotton, white underwear may help to alleviate symptoms.
Identify current treatment regimes for lichen sclerosis (LS) and the followup
that is requisite.
Aimed at preventing relapses of intense pruritus and mainstay is corticosteroids. Initially a potent steroid ointment, Clobetasol, may be necessary to provide relief, and should be used daily until relief and then tapered.
Biopsy of Lichen Sclerosis
Thinned epidermis, hyperkeratosis and elongation of the rete pegs.
Lichen planus usually involves vagina which LS does not.
Bartholin Gland Abscess location and treatment
Located at the 5 and 7 o-clock locations of the labia majora.
Treatment include incision and placement of a small balloon catheter into the gland, or marsupialization (surgical fixation of the cyst wall everted against the mucosa of the vula. Biopsy if above 40 years of age.
Definition of Lichen Sclerosis
Chronic, inflammatory dermatologic disease characterized by pruritus and pain, which mainly affects the anogenital region.
Definition of Advanced maternal age
Pregnant woman who will be 35 years or beyond at the estimated date of delivery.
Ramification of low hemoglobin (<10.5 g/dL) in pregnancy and its next steps
Preterm delivery
Low fetal iron stores
Identify thalassemia
Mild-therapeutic trial of iron
Moderate-ferritin and Hb
electrophoresis
Ramification of negative rubella in pregnancy and its next steps
Nonimmune to rubella
Stay away from sick individuals, vaccinate postpartum
Live attenuated vaccine
Ramification of negative Rh factor in pregnancy and its next steps
May be susceptible to Rh disease
If antibody screen negative, give Rhogam at 28 weeks, and if baby
is Rh positive, then also after delivery
Ramification of positive antibody screen in pregnancy and its next steps
May indicate isoimmunization
Need to identify the antibody, and then titer
Lewis lives, Kell kills,Duffy
dies
Ramification of positive HIV ELISA in pregnancy and its next steps
May indicate infection with HIV
Western blot or PCR, if positive then place patient on anti-HIV medicines, offer elective cesarean, or IV ZDV in labor
Intervention reduces Vertical transmission from 25% to 2%
Ramification of positive RPR in pregnancy and its next steps
May indicate syphilis
Specific antibody such as MHA-TP, and if positive then stage disease
Less than 1 year, penicillin ×
1; > 1 year or unknown,
penicillin IM each week × 3
Ramification of positive gonorrhea test in pregnancy and its next steps
May cause preterm labor , blindness
Ceftriaxone IM
Ramification of positive Chlamydia in pregnancy and its next steps
May cause neonatal blindness, pneumonia
Azithromycin or amoxicillin orally
Ramification of positive Hepatitis B surface antigen in pregnancy and its next steps
Patient is infectious
Check LFTs and hepatitis serology to determine if chronic carrier vs active hepatitis
Baby needs HBIG and hepatitis B vaccine
Ramification of positive urine culture in pregnancy and its next steps
Asymptomatic bacteriuria may lead to pyelonephritis 25%
Treat with antibiotic and recheck urine culture
If GBS is organism, then give penicillin in labor
Ramification of positive pap smear in pregnancy and its next steps
Only invasive cancer would alter management
ASC-US = re-Pap postpartum;
LGSIL, HSIL = colposcopy
Reflexive HPV not recommended with ASC-US
Ramification of positive nuchal translucency (11-13 weeks) in pregnancy and its next steps
May indicate trisomy
Offer karyotype and follow-up ultrasounds
Increased NT means increased risk, not definitive diagnosis
Ramification of positive Trisomy screen (16 - 20 weeks) in pregnancy and its next steps
At risk for trisomy or NTD
Basic ultrasound for dates; if dates confirmed, offer genetic amniocentesis
Most common reason for abnormal serum screening - wrong dates
Ramification of elevated 1 h diabetic screen (26 - 28 weeks) in pregnancy and its next steps
May indicate gestational diabetes
Go to 3h GTT
About 15% of those screened will be positive
Ramification of 2 abnormal 3h glucose tolerance test in pregnancy and its next steps
Gestational diabetes
Try ADA diet, monitor blood sugards, if elevated may need meds or insulin
About 15% of abnormal 1h GCT will have gestational diabetes
Ramification of positive GBS culture (35 - 37 weeks) in pregnancy and its next steps
GBS colonizing genital tract
Penicillin during labor
Helps to prevent early GBS sepsis of newborn
Implications of twin gestation for a pregnancy (both maternal and fetal effects)
A higher rate of congenital malformations, a two-time increased risk of preeclampsia and postpartum hemorrhage, and twin-twin transfusion (TTT) syndrome.
Velamentous cord insertion
Umbilical vessels separate before reaching the placenta, protected only by a thin fold of amnion, instead of by the cord or the placenta itself; these vessels are susceptible to tearing after rupture of membranes.
OCP and its effects on twin pregnancy
Oral contraceptives (OCPs) slow tubal motility, so it is important
to know if a mother has used OCPs within 3 months of becoming pregnant.
This is associated with an increased incidence of twinning.
How does fertility treatments increase risk of twin gestations?
Clomiphene induces ovulation and promotes the maturation of multiple follicles, therefore increasing the number of eggs available for fertilization. In vitro fertilization involves the transfer of two to four embryos to the uterus. If more than one implants, a twin or higher order gestation occurs. All dizygotic twins are dichorionic/diamnionic.
Treatment of TTT
Laser ablation of the shared anastomotic vessels at special centers, or serial amniocentesis for decompression.
Differentiating fetal bleeding from maternal blood
Apt test and Kleihauer-Betke test
Pelvic diaphragm muscles (3 important ones)
pubococcygeus, puborectalis, iliococcygeus
Test for cystocele
Q-tip test. A positive Q-tip test of a 60-degree angle of excursion or greater indicates a hypermobile urethra.
Diagnostic criteria of PCOS
oligomenorrhea, hyperandrogenism and multiple small cysts of the ovary on transvaginal ultrasound
What does presence of acanthosis indicate in PCOS
Insulin resistance
Management of PCOS based on fertility desires
Combination oral contraceptives have been the primary management of
long-standing PCOS. They are effective in regulating dysfunctional bleeding
and limiting unopposed estrogen (thus reducing endometrial cancer risk),
increasing the sex hormone–binding globulin (decreases free androgen levels),
and suppresses ovarian androgen production. Weight loss can reduce both the
hyperinsulinemia and hyperandrogenism with as little as 5% weight loss from
initial weight. Insulin-lowering agents, such as metformin, can be helpful in
reducing the hyperinsulinism and thus limiting the risk of developing cardiovascular
disease and diabetes mellitus.
For patients desiring pregnancy, clomiphene citrate is the agent of choice,
while metformin is only an adjunct.
Lab studies to be considered in PCOS
TSH, prolactin, lipid profile, glucose-intolerance screening, endometrial biopsy (in patients with long-standing anovulation and unopposed estrogen exposure), 17-hydroxyprogesterone
(congenital adrenal hyperplasia).
Most common causes of abnormal serum screening
wrong dates and multiple gestations.
Elevated maternal serum AFP
Open neural tube defect
Low maternal serum AFP
fetal Down syndrome
Ultrasound findings suspicious for having Down syndrome
Identification of a thickened nuchal fold, shortened femur length, or echogenic bowel.
What is the triple test?
2 serum analyte: PAPP - A and free b-hCG
Nuchal translucency
A 23-year-old G1 P0 woman at 20 weeks’ gestation undergoes an ultrasound
examination for size greater than dates. The ultrasound reveals hydramnios with an amniotic fluid index of 30 cm. The fetal abdomen reveals a cystic mass in the right abdominal region, and a cystic mass in the left abdominal area. Which of the following is the most likely associated condition?
This baby has the “double bubble” of duodenal atresia. The hydramnios results from the inability of the baby to swallow.
Duodenal atresia is strongly associated with fetal Down syndrome.
window for serum screening for down syndrome?
15 - 21 weeks
A 42-year-old woman with an 8-month history of increasing hirsutism and irregular menses. She denies the use of steroid medications, weight
changes, or a family history of hirsutism. Pelvic examination shows an 8-cm, right adnexal mass. Most likely diagnosis?
An ovarian tumor, probable Sertoli–Leydig cell
tumor.
Differential diagnosis of hirsutism
Cushing syndrome, Adrenal tumor, Congenital adrenal hyperplasia, PCOS, Sertoli-Leydig cell tumour
Onset and duration of hirsutism and its differential diagnosis
(faster growth is associated with tumors of adrenal and ovary, whereas slow onset since menarche is more likely polycystic ovarian syndrome)
A 6-year-old girl is noted to have breast development and vaginal
spotting. No abnormal hair growth is noted. A 10-cm ovarian mass is
palpated on rectal examination
Granulosa-theca cell tumour
Isosexual (no virilization) precocious puberty with an adnexal mass usually is a granulosa cell tumor of the ovary.
Normal LH:FSH ratio?
PCOS ratio?
Normal 1:1
PCOS >2:1
Microscopy of bacterial vaginosis
Clue cells
Microscopy of trichomonal vaginitis
Trichomonads
Microscopy of candidal vulvovaginitis
Pseudohyphae
