The objective of this study was to describe diagnosis and management of ectopic pregnancy using bedside transvaginal ultrasound (US) in an established emergency US program.

This was a retrospective study on patients presenting over a 2-year period performed at a level I urban academic emergency department (ED). The ED sees 78 000 patients annually and has a residency and active US program. Patients were eligible for inclusion if they were pregnant, seen in the ED for a first-trimester complication, and underwent a bedside emergency US suggesting an ectopic pregnancy.

Emergency department US logs were reviewed for findings suggestive of ectopic pregnancy. Medical records were reviewed for history, physical examination findings, laboratory results, additional diagnostic testing, management, hospital course, and a discharge diagnosis by the admitting obstetric service (OB). Patients with incomplete data were excluded from analysis. Statistical analysis consisted of descriptive statistics.

Results

Seventy-four patients ranging in age from 16 to 39 years (mean, 25 years) were included in the study. Eight patients with incomplete data were excluded from analysis. Emergency-physician US diagnoses included definite ectopic pregnancy (6/74), probable ectopic pregnancy (28/74), and possible ectopic pregnancy (40/74). Forty-seven (64%) of these patients were eventually diagnosed with definite ectopic pregnancy by the OB. During initial consultation, the OB disagreed with the diagnosis of ectopic pregnancy in 15 (32%) of the 47 eventual patients with ectopic pregnancy, calling them miscarriages. Other eventual diagnoses included 9 (12%) patients with possible ectopic pregnancy, 11 (14%) patients with miscarriage, and 7 (9%) with intrauterine pregnancy. Emergency sonologists found tubal rings in 9 (19%) patients with eventual ectopic pregnancy, complex adnexal mass in 29 (61%) patients, and a large amount of echogenic fluid in the cul-de-sac in 10 (21%) patients. Six (13%) patients had live ectopic pregnancy. The OB ordered a radiology US in 10 cases but did not change the diagnosis or management. β-Human chorionic gonadotropin (β-hCG) levels ranged from 41 to 59 846 mIU/mL (mean, 4602 mIU/mL), but for live ectopic pregnancy, the range was 2118 to 59 846 mIU/mL (mean, 36 341 mIU/mL). Seventeen (36%) patients had β-hCG levels of lower than 1000 mIU/mL. Of 47 eventual ectopic pregnancies, 29 (62%) patients underwent operative intervention, 17 (36%) patients received methotrexate, and 1 patient left against medical advice. Five (11%) of these patients with definite ectopic pregnancy were initially managed by emergency physicians with follow-up ED visits and serial US examinations without OB consultation.

Conclusion

Our study demonstrates that with increased experience, emergency sonologists can accurately diagnose ectopic pregnancy. Furthermore, patients at risk for ectopic pregnancy should not be denied US examinations if their β-hCG levels fall below an arbitrary discriminatory zone.

Srikar Adhikari MD, Michael Blaivas MD, RDMS and Matthew Lyon MD, RDMS
Section of Emergency Ultrasound, Department of Emergency Medicine, Medical College of Georgia, Augusta, Georgia 30912-4007, USA
Section of Emergency Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, USA
Received 27 June 2006;  revised 31 October 2006;  accepted 12 November 2006.  Available online 30 June 2007.