This 2017 ACEP Clinical Policy examines two questions in patients that present to emergency department with a positive pregnancy test.  The policy reviews the literature and looks at HCG values and makes recommendations on the use of ultrasound and HCG levels.  All these policies should  be used in conjunction with clinical judgment.

1. Should the emergency physician obtain a pelvic ultrasound in a clinically stable pregnant patient who presents to the ED with abdominal pain and/or vaginal bleeding and a β-hCG level below a discriminatory threshold?

There is a Level B recommendation to Perform or obtain a pelvic ultrasound for symptomatic pregnant patients with any β-hCG level.

Potential Benefit of Implementing the Recommendations: Improved patient safety by decreasing the risk of missing an ectopic pregnancy among patients with a low β-hCG value. In addition, the potential for earlier diagnosis of a viable intrauterine pregnancy in many patients will likely reduce the need for further follow-up testing for ectopic pregnancy.Potential Harm of Implementing the Recommendations: Increased use of ultrasound with associated costs and increased ED length of stay for patients, as well as a potential increase in unnecessary specialty consultations for false-positive or equivocal ultrasound results.

2. In patients who have an indeterminate transvaginal ultrasound result, what is the diagnostic utility of β-hCG for predicting possible ectopic pregnancy?

There is a Level B recommendation to not use the β-hCG value to exclude the diagnosis of ectopic pregnancy in patients who have an indeterminate ultrasound result.

Potential Benefit of Implementing the Recommendations: Reduced risk of missing an ectopic pregnancy in patients with an indeterminate ultrasound result.Potential Harm of Implementing the Recommendations: Additional resource use, including potential admissions and/or an increase in invasive management of patients without an ectopic pregnancy who have an indeterminate ultrasound result.

Source: Clinical Policy: Critical Issues in the Initial Evaluation and Management of Patients Presenting to the Emergency Department in Early Pregnancy – Annals of Emergency Medicine