Pocket ObGyn – Uterine Inversion / Amniotic Fluid Embolism / Malpresentation / Fetal Meconium / Chorioamnionitis / Endomyometritis
See Abbreviations

Definition and Epidemiology

• Complete: Internal lining of fundus extrudes through cervical os
• Incomplete: Portion of fundus extrudes to the cervix but not through the os
• 1 in 2500 deliveries (J Reprod Med 1989;34:173)

Etiology

• Excessive umbilical cord traction during 3rd stage of labor on a fundally implanted placenta
• Impaired uterine contraction after deliv of placenta
• Uterine Abn placentation (eg, placenta accreta)

Physical Exam

• Visualization of endometrial lining through the cervical os (meaty, red tissue)
• Inability to palpate fundus of uterus

Treatment and Medications

• Reinvert the uterus w/ constant/gentle pres, in a cephalad direction, on the fundally inv portion of the Reinversion becomes more difficult w/ delay. Bleeding ­­­
• General anesthesia & tocolytic agents may be needed to assist w/ replacing the uterus; monit closely for HoTN & increased bleeding, such as:

Magnesium sulfate 2 g IV Terbutaline 0.25 mg IV or IM Nitroglycerine 50 mcg IV

Halogenated anesthesia (isoflurane, sevoflurane)

• Obstetrical emergency if reinversion is not successful ® laparotomy ® elevate fundus by round ligaments & restore cephalad with a hand below in the vagina.

Aminiotic Fluid Embolism

Definition and Epidemiology

• Presence of amniotic fluid in mat circulation, occurring usually at deliv
• Incid of 7/100000 births. Unpredictable & unpreventable

Pathology

• Poorly Amniotic fluid enters mat circulation ® precipitation of DIC & shock in mother (cardiogenic vs. distributive)
• Thought to be due to tumultuous labor or uterine manipulation, but unk

Clinical Manifestation and Physical Exam

• Sudden profound HoTN from cardiogenic shock, hypoxemia, DIC
• Acute in onset & sev, life threatening ® ICU Often rapidly fatal
• Acute destabilization of vital signs – usually becoming unresponsive rapidly

Diagnostic Workup/Studies

• Clinical dx: HoTN, hypoxemia, cardiorespiratory failure
• Ddx: Placental abruption, uterine rupture, peripartum cardiomyopathy, sepsis, PE, anaphylaxis, MI

Treatment and Medications

• If deliv has not yet occurred, emergent (often bedside) deliv of the fetus is warranted
• Supportive rx of hemodynamic instability is the mainstay of Call for help.

Malpresentation

Definition and Epidemiology

• Fetal presentation refers to the presenting part of the fetus (lowest or nearest cervix). Poss presentations include:

Cephalic presentation divided into vertex, sinciput, brow, & face Breech presentation divided into frank, complete, & footling

Incid of breech presentation declines w/ increasing gestational age, starting at

~33% at 21–24 w ® 11% at 32 w ® 3–4% at ³37 w Other presentation: back (up or down), shoulder, etc

 

Breech presentations
Frank breech	Footling breech	Complete breech
Fetal hips flexed, fetal knees extended; “butt 1st”	Fetal foot or knee is below the breech; “foot 1st”	Fetal hips flexed, fetal knees flexed

Etiology and Diagnosis

• Uterine anomalies (bicornuate, septum), fibroids, placentation defects (previa), multiparity, poly/oligohydramnios, contracted mat pelvis, fetal or neuro defect, short umbilical cord
• Presenting part is felt w/ vaginal exam, identified on Leopold Verify w/ sono.

Treatment

• Breech & mentum post face presentations ® usually Planned vaginal breech deliv a/w ­ perinatal mortality, neonat mortality, & serious neonat morbidity than planned CD (5% vs. 1.6%) (Lancet 2000;356:1375)
• External cephalic version may be attempted (at >36 w, usu 36–38 weeks) to convert a breech presentation to a cephalic. Contraindicated in pregnancies where CD is indicated (eg, placenta previa), gestational age <36 w (high rate of reversion).

(ACOG Practice Bulletin #17, Reaffirmed 2012)

Fetal Meconium

Definition and Epidemiology

• Fetal mec stool usu passed in the 1st days of If prior to deliv ® meconiumstained amniotic fluid, which if breathed by fetus can ® mec aspiration syn
• Meconium-stained amniotic fluid in ~9% of live births w/ 1% mec aspiration syn
• Most common in pregnancies reaching 41–42 w gest (post term)

Pathology

• Aspiration of mec by the fetus ® dz in neonat Hypoxemia in neonate secondary to pulm injury
• Injury from mechanical obst of the airway, inflamm damage caused by irritation in the lungs, or by inactivation of surfactant w/i alveoli

Clinical Manifestations

• Dark brown to green amniotic fluid when membranes rupture or after (describe as thin, mod, thick)
• Note color & presence or absence of particulate matter

Diagnostic Workup/Studies

• Mec aspiration can occur during deliv – mec aspiration syn is diagnosed w/ neonat hypoxemia in the presence of aspiration

Treatment and Medications

• Amnioinfusion does not prevent mec aspiration syn
• Peds should be at deliv when mec is noted on rupture of membranes
• To prevent aspiration, nonvigorous neonates should not be initially stimulated at the perineum. Allow peds to evaluate & perform tracheal suction w/

Chorioamnionitis

Definition and Epidemiology

• Infxn of the amniotic membrane & chorion of the placenta
• Complicates 1–4% of all births in US
• Risk factors – ­ duration of membrane rupture, GBS bacteriuria, prolonged labor, multi vaginal exams, internal monitoring

Etiology

• Infxn is present in the chorionic membranes, umbilical cord, or placenta
• May be transmitted via ascending infxn from lower genital tract, transplacentally from mat bld stream, or iatrogenically (eg, via amniocentesis)
• Typical organisms: Ureaplasma, Mycoplasma hominis (more common in ascending infections), GBS, Escherichia coli, Gardnerella vaginalis, Listeria monocytogenes (more common w/ transplacental spread from mat infxn)

Physical Exam

• Mat: Fever (>38°C or 4°F), fundal tenderness, purulent or foul smelling discharge, tachy >100 bpm. Fetal: tachy >160 bpm
• Mat fever + tachy is highly Clinical dx.
• Rule out other causes fever/tachy (eg, epidural fever, administration of ephedrine)

Diagnostic Workup/Studies

• Clinical dx: Mat fever is the most important marker of the condition
• Lab eval: Rarely performed, though amniotic fluid culture is the gold std for dx; other suggestive amniotic fluid markers include gluc £15 mg/dL, IL-6 >9 ng/mL, positive MMP, WBC > 30/mm³, leukocyte esterase positive on dipstick. IL-6, MMP, & leukocyte esterase ­ sens/spec.

Treatment and Medications

• Acetaminophen for fever control ® ¯ incid of neonat encephalopathy
• IV Abx:

Vaginal deliv: Ampicillin 2 g IV q6h + Gentamicin 1.5 mg/kg IV q8h until deliv; one additional dose after deliv of each antibiotic ® ¯ endomyometritis

CD: Same as vaginal deliv + Clindamycin 900 mg IV once OR Metronidazole 500 mg IV once; consider continuing Abx until pt is afebrile for 24–48h (generally w/ Gentamicin/Clindamycin or Ampicillin/Gentamicin/Clindamycin).

Definition and Epidemiology

• Infxn of the endometrial, parametrial, or myometrial tissue usually >24 h after deliv (low grade mat fever common during this period). Clinical suspicion guides
• Incid varies w/ mode of deliv:

Vaginal deliv: 0.2–0.9%; higher if chorio was present

CD: 5–30%; decreased w/ perioperative prophylactic Abx

Etiology

• Similar to chorio (ascending infxn from lower genital tract). Also introduced infxn from surgical trauma. Usually polymicrobial.
• Infxn from genital tract can invade the surgical wound

Physical Exam

• Physical exam is similar to chorio w/ mat fever & fundal tenderness
• Malodorous lochia may be present

 

Diagnostic Workup/Studies

• ­ WBC (although commonly elevated in labor & postoperatively anyway)
• Largely clinical dx & depends on context/suspicion. Imaging generally unnecessary unless suspecting pelvic abscess or larger/progressing
• Cx for chlamydia & gonorrhea could be considered if not already obtained
• Routine endometrial culturing is not helpful secondary to genital tract contamination

Treatment and Medications

• Treat w/ broad spectrum >90% respond to Gentamicin (5 mg/kg IV q24h) + Clindamycin (900 mg IV q8h). IV Abx until asymptomatic/afebrile for 24–48 h; no data exist to support continued oral antibiotic rx. Clinical response guides antibiotic coverage/spectrum (eg, broaden if no response in ~24 h or clinically worsening) and duration of treatment.
• Acetaminophen/Ibuprofen for mat Breastfeeding okay.

See Abbreviations