emDOCs Podcast – Episode 30: Ectopic Pregnancy
- Jun 8th, 2021
- Brit Long
Today on the emDOCs cast with Brit Long, MD (@long_brit), we cover ectopic pregnancy.
– Ectopic pregnancy affects up to 2% of all pregnancy, but up to 16% of those with pregnancy related issue in the ED. Leading cause of trimester maternal death.
– Most common location is in fallopian tube. Others include interstitial, corneal, cervical.
– Heterotopic rate 1/30,000, but in those with assisted reproduction, the rate is 1/100.
– Most deaths occur prior to or just after ED arrival.
– Not present in half of patients. Factors include prior tubal surgery/ectopic pregnancy, previous PID, assisted fertility, smoking.
– Consider in all women of childbearing age with abdomen/pelvic pain, flank pain, syncope, hypotension. Shock and rebound pain can present in those with ruptured ectopic pregnancy (< 20%). Vital signs can be falsely reassuring or demonstrate bradycardia in the setting of significant bleeding.
– Triad: abdominal pain (80-90%), missed menses 4-12 weeks after last menstrual period (75-90%), vaginal bleeding (50-80%). Full triad not present in up to 25%, and 10% have no symptoms.
– Exam: adnexal tenderness (75-90%), adnexal mass (50%), uterine enlargement (25%), orthostasis (10%)
– Evaluation: 1) Evaluate for pregnancy and 2) Stable or unstable?
– Unstable -> FAST -> if positive, assume ectopic and resuscitate
– Stable and FAST +/- -> TVUS
– Labs: serum β-hCG, CBC, CMP, blood type
– US – intrauterine vs ectopic pregnancy
– Coordinate management with OBGYN
β-hCG:Urine β-hCG may be falsely negative, so obtain serum β-hCG. No hCG level or series of hCG levels can rule out ectopic. US has moderately high sensitivity in diagnosing ectopic pregnancy in patients with β-hCG < 1000 IU/I. ACEP’s recent clinical policy states at a Level B recommendation, “Do not use the β-hCG value to exclude the diagnosis of ectopic pregnancy in patients who have an indeterminate ultrasound.” β-hCG can be rising, falling, plateau or even zero.
Transvaginal US is the best test to exclude/diagnose ectopic pregnancy. Gestational sac alone should not be used to confirm IUP. Obtain US, no matter β-hCG (even if negative).
1) Gestational sac with yolk sac or embryo in uterus -> IUP
2) Gestational sac with or without yolk sac outside the uterus -> ectopic pregnancy -> medical vs. surgical management of ectopic
3) No pregnancy -> non-diagnostic -> pregnancy may be too early to be visualized. 8-40% of these turn out to be ectopic. Discriminatory zone varies between 1000 to 2000 IU/L. However, there are many issues with β-hCG levels, as an ectopic can present at any level. If β-hCG is greater than this level and no IUP is seen on US, an ectopic may be present. If the β-hCG is less than this zone, pregnancy is an early IUP, spontaneous miscarriage, or ectopic. Patient needs follow-up.
– Hemodynamically stable or tubal rupture -> surgery.
– Methotrexate (MTX) is a folic acid antagonist that is 95% effective in certain patients: β-hCG <5000 mIU/mL, no fetal cardiac activity, mass < 3-4 cm in largest diameter, no heterotopic pregnancy, not currently breastfeeding, no lab abnormalities to MTX, patient is willing and able to follow up. If the patient does not meet these criteria, she is not eligible for MTX.
– Expectant: Stable patients with β-hCG < 200, not increasing, 75% resolve on their own. These patients require close follow up.
– Rhogam: Give Anti-D immunoglobulin to non-sensitized RhD negative women to prevent development of RhD antibodies. It should be given as soon as possible after the immunizing event (within 72 hours) and effects last for 12 weeks.
– Patient who received MTX may experience abdominal pain, which is a common side effect. This may be due to tube rupture (4-6% of patients, usually within 2 weeks of receiving MTX). Obtain CBC, β-hCG, and US. Consult OBGYN. If unstable, positive FAST -> OR.