Zak Grunwald, MD, PGY-1
The Article: Morgan et al. “Effect of Emergency Physician–Performed Point-of-Care Ultrasound and Radiology Department–Performed Ultrasound Examinations on the Emergency Department Length of Stay Among Pregnant Women at Less Than 20 Weeks’ Gestation.” J Ultrasound Med 2018; 0278-4297. doi:10.1002/jum.14607
The Idea: Over 5 million women visit emergency departments in the United States each year for problems related to pregnancy. When their presentation is with abdominal pain or vaginal bleeding, the life-threatening diagnosis of ectopic pregnancy must be ruled out by demonstrating an intrauterine pregnancy (IUP) on ultrasound (US). Historically, these scans have been performed by radiologists, but retrospective studies have demonstrated that ED length of stay (LOS) can be be reduced by ~20% when they are performed by emergency physicians; however, these findings had never been validated in a prospective study. The intention of this research by Morgan et al. was to prospectively examine whether point-of-care ultrasound (POCUS) for excluding ectopic pregnancy would decrease ED length of stay when compared to radiology department performed ultrasound.
The Study:
This study was a multicenter randomized controlled clinical trial performed at an urban academic safety net hospital and two Naval medical centers starting in 2013.
Inclusion Criteria: pregnant women aged 18-55 presenting to the ED with a chief concern of abdominal pain or vaginal bleeding
Exclusion Criteria: prior documentation of an IUP, estimated gestational age >20 weeks by last menstrual period, open cervical os on exam, peritoneal abdomen, unstable vital signs, or if patient is incarcerated
Interventions: Emergency attending physicians and residents were provided with a short lecture and video presentation on US criteria for IUP, as well as an overview of study selection criteria. A convenience sample of patients was enrolled and randomly assigned to either POCUS or radiology ultrasound (RDUS). Patients randomized to POCUS could additionally undergo radiology US at the discretion of the emergency attending physician.
Primary Endpoint: ED length of stay, defined as time from placement in ED examination room to time of discharge or admission order
Secondary Endpoint: Time to diagnostic result, defined as time from placement in ED examination room to time ED attending recorded becoming aware of US result
Results: 106 patients were randomized to RDUS arm, 116 to POCUS arm. In the POCUS arm, 65 patients only underwent POCUS, while 53 patients underwent POCUS and RDUS. Patients in this last group were younger and at earlier gestational age than patients only undergoing POCUS. For the primary endpoint, ED LOS was shorter in the POCUS arm (181 minutes, 95%CI 152-206 minutes) compared to the RDUS arm (201 minutes, 95%CI 193-221 minutes; p = .014). For the secondary outcome, time to diagnostic result was also shorter in the POCUS arm (87 minutes, 95%CI 61-120 minutes) compared to the RDUS arm (136 minutes, 95%CI 116-148 minutes; p = .003). Adjusting for institutional variation, ED LOS in the POCUS arm was 31 minutes faster (95%CI -64-1 minute) than the RDUS arm, and time to diagnostic result was 36 minutes faster (95%CI -67- -5 minutes). In a subgroup analysis dividing the POCUS arm into patients who only underwent POCUS and those who underwent POCUS and RDUS, patients only receiving POCUS had the shortest LOS (126 minutes, 95%CI 105-140 minutes) and time to diagnostic result (45 minutes, 95%CI 30-51 minutes), and patients receiving both POCUS and RDUS had the longest ED LOS (246 minutes, 95%CI 210-286 minutes) and time to diagnostic result (180 minutes, 95%CI 158-211 minutes).
The Takeaway: This was the first prospective randomized trial to demonstrate that ED point-of-care ultrasound for ruling out ectopic pregnancy in pregnant women with abdominal pain or vaginal bleeding reduces ED length of stay and time to diagnosis when compared to radiology performed ultrasound. While patients ultimately requiring both ED POCUS and RDUS for their diagnosis had the longest ED LOS and time to diagnosis in this study, this was offset by the reduced ED LOS and time to diagnosis in the whole ED POCUS arm. While this study did not examine clinical outcomes, e.g. number of missed ectopics, these results support the use of ED POCUS from a systems perspective given the frequency of this common ED chief concern.