Out of Place, Out of Time: Ectopic Pregnancy in the ED

-Case-

A 29-year-old woman presents to the emergency department with 6 hours of lower abdominal pain and vaginal bleeding. She reports her last menstrual period was six weeks ago and mentions intermittent lightheadedness. Her vital signs are notable for tachycardia to 110 bpm and a blood pressure of 100/65 mmHg. A urine pregnancy test is positive.

Given her presentation, vitals, and labs thus far, what potential causes come to mind?

-Evaluation-

Any patient of reproductive age with vaginal bleeding should prompt concern for an ectopic pregnancy! Let’s break down the most common presentations of this pathology:

• Abdominal pain (typically unilateral, sharp, or crampy, but a presentation not like this by no means suggest no ectopic)
• Vaginal bleeding
• Lightheadedness or syncope
• In more progressed cases, signs of hemodynamic instability 

Risk factors for an ectopic include a prior ectopic pregnancy, a history of pelvic inflammatory disease, prior tubal surgery or sterilization, IUD use, smoking, and advanced maternal age.

With this in mind, let’s talk diagnosis! In short, this process is actually fairly algorithmic, and it all starts with a urine pregnancy test! If the b-hCG is negative, we’ve successfully ruled out an ectopic. Assuming it’s positive and vitals are not unstable, however, we move on to other labs, particularly a type and screen, CBC, and CMP – while our patient is stable now, that can change very quickly, so getting ahead of the blood resuscitation process is key!

Next, a bedside vaginal US/formal ultrasound can help us figure out if there is a true intrauterine pregnancy or not. A transvaginal ultrasound is the gold standard and here, we are mostly looking for the absence of an intrauterine pregnancy, presence of an adnexal mass, or free fluid in the pelvis to validate our concern for an ectopic.

-Management-

Alright – now we know our patient has an ectopic pregnancy. What comes next? At this point, please make sure our friends over at OBGYN are aware to help guide you along…

First are foremost – is our patient still stable? If not, we give STAT IV fluids and blood products as needed. Additionally, our patient is likely already on their way to the OR.

If they are (thankfully) still stable, we opt for medical management. Methotrexate (MTX) is the MVP for unruptured ectopic pregnancies in stable patients. The qualifying criteria can be quite strict, but it includes no fetal cardiac activity, adnexal mass <4 cm, and hCG <5,000. Additionally, patients who are breastfeeding or have known renal/hepatic disease should not be taking MTX. On the other hand, if your patient does not fit into this laundry list of qualifications for MTX, despite them being stable, surgery is indicated.

-Fast Facts-

Ectopic pregnancy isn’t just a medical emergency; it’s a diagnostic puzzle. Keep your suspicion high, especially for patients with risk factors and classic symptoms. Timing is everything – get it right, and you might just save a life.

Want to learn more? Read our in-depth study guide about ectopic pregnancy!

Cheers,

Tamir Zitelny, MD

-References-

1. Bontempo LJ, Cosby KS. Updates in emergency medicine: ectopic pregnancy. Am J Emerg Med. 2023;71:143-150. doi:10.1016/j.ajem.2023.03.040
2. Elson CJ, Jurkovic D. A fresh look at treatment for ectopic pregnancy. Lancet. 2022;400(10364):550-552. doi:10.1016/S0140-6736(23)00181-2
3. Stein JC, Wang R, Adler N, Boscardin J, Jacoby VL, Callen PW. Emergency medicine myths: ectopic pregnancy evaluation, risk factors, and presentation. J Emerg Med. 2017;52(4):449-456. doi:10.1016/j.jemermed.2016.10.025
4. Hahn SA, Promes SB, Brown MD, et al. Clinical policy: critical issues in the initial evaluation and management of patients presenting to the emergency department in early pregnancy. Ann Emerg Med. 2012;60(3):381-390.e28. doi:10.1016/j.annemergmed.2012.04.005
5. Vinson DR. Evaluation and management of ectopic pregnancy in the emergency department. J Emerg Med Reports. 2017;38(20):237-243.