Obstetrics Flashcards
- Placenta previa
- Implantation of placenta over/near the cervical os
- Types: complete, partial, marginal or low-laying placenta
- Risk factors: prior placenta previa, multiple gestation, prior c-section, smoking
- Clinical: painless vag. bleeding 3rd trimester, contractions
- Diagnosis: transabd. US
- Management: dep. on gest. age. (c-section if lots of bleeding, vag. delivery possible is low-laying placenta)
- Complications: transverse lie, PPROM, IUGR
- Other placental abnormalities (not placenta previa)
- abnormal attachment of placenta through myometrium as a result of defective decidual formation
- Types:: superficial (accreta), villi extends more deeply (increta), villi extending through uterine serosa (pacreta)
- Risk factors: prior c-section, Asherman syndrome, placenta previa, high maternal age
- Clinical: delayed delivery of placenta w. profuse bleeding
- Management: laporatomy w. high vol. hemorrhage expected, schedulaed c-section + hysterectomy is done at w. 34, leaving placenta in situ
- Multiple gestation
≥ 2 embryos/fetuses occupy the uterus simultanously
Types
Monozygotic: splitting of an embryo
* Division within 72h: dichorionic, diamniotic(30%)
* Division after 4-8d: monochorionic, diamniotic (69%)
* Divison after 8-13d: monochorionic, monoamniotic (1%)
* Division ≥ 13 days: conjoined twins
Dizygotic: fetilization of ≥ 2 eggs produced in a single menstrual cycle
Increased risk: fam. history, high materna age, IVF, ovarian stimulation (clomiphen)
Management:
* Vertex-vertex: vag. delivery
* Other presentations: c-section
Abnormalities of twinning process:
* Interplacental vascular anestemosis (arterial-venous most common)
* Twin-twin transfusion syndrome (worse for the recipient, not the donor).* Donor: IUGR, hypoveolemia, hypoT. Recipient: HF*
* Fetal malformations (in e.g. arterial-arterial anest.)
* Retained dead fetus syndrome: can result in DIC if not reabsorbed within w.23
- placental abruption
premature seperation of a normally implanted placenta from the uterus, usuallt after 20w of gestation
Order of events
* Hemorrhage into decidua basalis, then formation of decidual hematoma. This results in further hemorrhage and seperation, compression and destruction of placental tissue.
* Blood can travel up (concealed hemorrhage) or downwards (external/revealed bleeding)
Risk factors
* Maternal hypertension!!
* Recurrent abruptions
* Old maternal age, polyhydramnios, trauma, chorioamnionitis
* Smoking, cocaine use
Clinical presentation
* Painful caginal bleeding w. uterine tenderness, increased tone and hyperactivity
* Hemorrhagic shock, signs of DIC
Diagnosis: clinical (US only detect 2%)
Treatment:
* Maternal and fetal monitoring of hemodynamic state
* Checking Ht and coag. profile
* Delivery if maternal or fetal instability, severe hemorrhage or near-term pregnancy
Complications:
* Blood loss –> hemodynamic instability, shock, DIC (placental abruption no.1 cause of DIC in pregnancy)
* Sheehan syndrome (late complication)
* Fetal death
33. Amniotic fluid
- Amniotic fluid
Clear, yellowish liquid (98% H2O) sorrounding the fetus during pregnancy.
Volume changes
* 30 ml at week 20
* 800 ml at week 34
* 600 ml at week 40
Functions:
* Protecting fetus for trauma
* Creating a physical space for fetal movement
* Fetal swallowing essential for GI and lung dev.
* Guards against umbilical compression
Fluid amount regulation
* Fetal swallowing (750ml/day)
* Lung secretion (350ml/day, but immediatly swallowed)
* Urinary production (1L/day)
* Intramembranous transfer
Fluid measurement
* No safe way of duing this, so using US to measure the AFI
* Oligo = AFI < 5cm
* Poly = AFI > 23-25 cm
33. Polyhydramnios
- Polyhydramnios
AFI > 23-25cm
Etiology
* Fetal malformations (especially regarding swallowing, e.g. GI abnormalities)
* Maternal diabetes
* Multiple gestation
* Fetal disorders: anemia, infections etc.
Clinical: Usually asymp., mother can have difficulty breathing and it can be difficult hearing/feeling the baby
Diagnosis:
* AFI > 23-25cm
* Find the cause: OGTT on mother, checking for infections, look for fetal abnormalities on US
Treatment:
* Individual assessment
* Planned delivery at w39
* Monitoring (NST 1/week)
Complications
* PROM, preterm labor
* Fetal death
* Umbilical cord prolapse
* Maternal respiratory compromise
- Oligohydramnios
Etiology
* Fetal malformations (especially regarding urine production)
* Postterm pregnancy
* PROM
* Uteroplacental insuficciency (preeclampsia, HT, placental abruption etc.)
* Drugs (ACE inh., NSAIDS)
Clinical: Usually asymp., decreased movements of the fetus, painful movements
Diagnosis:
* AFI > 5 cm
* Find the cause: US for fetal malformations, PROM?, amniocentesis, check umbilical artery using doppler
Treatment:
* Individual assessment
* If > 36 w = delivery
* Monitoring (NST/ 4 weeks, AFI)
Complications
* IUGR
* Fetal death
* Limb contractures
* Delayed lung maturation
- Postpartum hemorrhage
Definition: Blood loss of >500ml in vag. delivery or >1000ml in c-section
Etiology:
* uterine atony (75%)
* Vaginal/cervical lacerations
* Retained placenta
* DIC
Diangosis: clinical, inspection, palpation
* Doughy uterus = atony
* Firm uterus = retained placenta
* Absent uterus = inversion
Management: ABC, Crystalloids, CBC, coag profile, treat underlying cause, D&C, embolisaiton of the uterine a.
- Inversio uteri
Corpus turns inside out and protrudes into vagina or beyond the introitus. Can be caused by too much traction applied to umbilical cord in an attempt to deliver the placenta. Diagnosis is clinical.
Treatment: manual reduction by pushing up the fundus until the uterus is returned to norkmal (before removing placenta if it’s still attached). IV analgestics and sedatives sometimes neeedd. Start oxytocin once uterus is in place.
- Lesions in the birth canal. Uterine rupture.
- Vulvovaginal lacerations
- Cervical lacerations
- Perineal lacerations
- Uncontrolled, traumatic or operative
- 1st degree: perineal mucosa
- 2nd degree: perineal muscles
- 3rd degree: ext. anal sphincter
- 4th degree: int. anal sphincter + rectal mucosa
Uterine rupture
Spontanous tearing of the uterus, may result in expelling of the fetus into peritoneal cavity. High morbidity and mortality.
* Most commonly over healed c-section scars
* Etiology: uterine overdistension, excessive use to uterotonics, fetal version, failure to recognize labor dystocia
* Clinical: fetal brady, variable decelerations, hypovolemia, abd. pain
* Diagnosis and tr: laparatomy + c-section + hysterectomy
- Management of newborn after delivery
Apgar score at 1 min and 5 min after birth
* Activity, pulse, grimace, appearance, respiration
* 7-10: excellent
* < 6 at 5 min linked to higher morbidity and mortality
Evaluation of gross deformities
Clamp and cut umbilical cord (check for 2a and 1v)
Adm. vit K 1 mg IM to prevent hemorrhagic disease
Weigh and measure newborn
* weight: 2500-4300kg
* length: 50 cm
* head circ: 35 cm
* abd. circ: 20 cm
Wrap baby, give to mother, early breastfeeding
- Breast diseases
Mastitis
Fibrocytic changes
Hyperplasia
Galactocele
Fibroadenoma
- Physiologic changes in renal system
- RBF and GFR increase (reaches 40-50% above normal mid-gestation)
- Frequent urination due to compression of bladder
- Increased capacity of bladder (from 300ml-1500ml)
- Sodium and water retention (activation of RAAS, incr. angt2
- Blood volume incr. with 40% (constricting peripheral vasculature)
- Physiologic hormonal changes
- Enlargement of thyroid gland (estrogen incr TBG, incr. tot. thyroid hormones. TSH, free T3-4 unchanged)
- BMR incr. 10-30%
- Decr. Ca2+ –> Incr. PTH
- Enlargement of pituitary, incr. risk of Sheehan’s syndrome
- ACTH and cortisol increased (might contribute to gestational diabetes
Others: hCG, hPL,’ CRH, prolcatin, progesterone, estrogen, oxytoxin
- Signs of pregnancy
Presumptive
Probable
Positive
