The major recommendations for the emergency department management of women of childbearing age presenting with undifferentiated vaginal bleeding and/or abdominal pain suggestive of ectopic pregnancy are provided in the form of an algorithm, "Undifferentiated Vaginal Bleeding/Abdominal Pain Suggestive of Ectopic Pregnancy Clinical Pathway."
The grades of the strength and consistency of evidence (A1, A2, B1, B2, C1, C2, D) are defined at the end of the "Major Recommendations" field.
Definitions
Quantitative beta human chorionic gonadotropin (beta-hCG): expressed in mIU/mL per the World Health Organization Third International Standard (International Reference Preparation)
Clinical Evaluation
Data suggest that women with normal intrauterine pregnancies rarely experience pain or vaginal bleeding at below-threshold beta-hCG levels (1,000, 1,500, or 2,000 mIU/mL) and that women who do present to the emergency department (ED) with pain and/or vaginal bleeding and low beta-hCG levels are much more likely to have ectopic or abnormal intrauterine pregnancies (Kohn et al., 2003). Therefore, a conservative approach to the evaluation of women of childbearing age presenting to the ED with abdominal pain and/or vaginal bleeding suggestive of ectopic pregnancy has been adopted.
- Women of childbearing age presenting to the ED with abdominal pain and/or vaginal bleeding will receive a urine test for pregnancy at triage ("Clinical policy," 2000. Evidence Grade = B1).
- Women with positive urine pregnancy tests who have not previously had an intrauterine pregnancy document by ultrasound will receive quantitative beta-hCG testing and a formal endovaginal ultrasound (Bloch, Baumann, & Strout, 2006; Dart, Kaplan, & Cox, 1997; Kaplan, et al., 1996. Evidence Grade = C1).
- Women with vaginal bleeding will also undergo blood type and screen for Rh as well as hematocrit evaluation (Royal College of Obstetricians & Gynaecologists, 2004; "Clinical policy," 2003. Evidence Grade = B1).
- Endovaginal ultrasound will not be dependent upon beta-hCG level (Gracia & Barnhart, 2001. Evidence Grade = B2)
- For women without intrauterine pregnancy observed by endovaginal ultrasound, an Obstetrics/Gynecology consult will be obtained (Tayal, Cohen, & Norton, 2004. Evidence Grade = D).
General Considerations
- Always consider the possibility of heterotopic gestation, particularly in women who have utilized assisted reproductive technologies such as in vitro fertilization or gamete intrafallopian transfer (Dimitry et al., "Heterotopic pregnancy," 1990; Dimitry et al., "Nine cases of heterotopic pregnancies," 1990; Molloy et al., 1990. Evidence Grade = D).
- For women who have conceived naturally, the presence of an intrauterine pregnancy makes the likelihood of ectopic pregnancy extremely rare as the incidence of heterotopic gestation has been reported to be between 1 in 4,000 and 1 in 8,000 (Hann, Bachman, & McArdle, 1984; Reece et al., 1983; Bello et al., 1986; van Dam, Vanderheyden, & Uyttenbroeck, 1988; Vanderheyden & van Dam, 1987. Evidence Grade = D).
- It should be noted that several studies have shown a prevalence of normal ultrasound examination in 5% to 27% of women who actually have ectopic pregnancy (Stabile, Campbell, & Grudzinskas, 1988; Mahoney, et al., 1985; Nyberg et al., 1987. Evidence Grade = C1).
Definitions:
Evidence Grading
A1 = Evidence from well-designed meta-analysis or well-done systematic review with results that consistently support a specific action
A2 = Evidence from one or more randomized controlled trials with consistent results
B1 = Evidence from high quality evidence-based practice guideline
B2 = Evidence from one or more quasi experimental studies with consistent results
C1 = Evidence from observational studies with consistent results (e.g., correlational, descriptive studied)
C2 = Inconsistent evidence from observational studied or controlled trials
D = Evidence from expert opinion, multiple case reports, or national consensus reports.