We. Durston et al., Ultrasound availability in the evaluation of ectopic pregnancy in the ED: Comparison of quality and cost-effectiveness with different approaches, AM J EMER M, 18(4), 2000, pp. 408-417
The liberal use of ultrasonography has been advocated in patients with firs
t trimester cramping or bleeding to avoid misdiagnosis of ectopic pregnancy
in the emergency department (ED). The cost-effectiveness of different appr
oaches to ultrasound availability has not been previously reported. in this
study, we investigated measures of quality and cost-effectiveness in detec
ting ectopic pregnancy in the ED over a 6-year period, divided into three a
pproximately equal epochs with three distinct approaches to ultrasound avai
lability The study retrospectively identified 120 cases of ectopic pregnanc
y seen in the ED over 6 years. There was significant improvement in the per
centage of patients with ectopic pregnancy who were documented to have abse
nce of intrauterine pregnancy (IUP) at the first visit from 76% during Epoc
h 1, when there was limited availability of ultrasound through medical imag
ing (MI Sono), to 88% in Epoch 2, when MI Sono was readily available, to 96
% in Epoch 3, when both Mi Sono and ultrasound by emergency physicians (ED
Sane) were readily available (P = .02). The estimated number of MI Sonos or
dered by emergency physicians in patients at risk for ectopic pregnancy inc
reased from 5.2 per ectopic pregnancy in Epoch 1 to 11.8 per ectopic pregna
ncy in Epoch 2, and declined to 5.5 per ectopic pregnancy in Epoch 3, when
19.9 ED Sonos per ectopic pregnancy were also done. The cost of ED Sono in
Epoch 3 was more than offset by savings from avoiding calling in ultrasound
technicians after regular medical imaging department hours. The specificit
y of ED Sono in ruling in an IUP was 100% (95% Ct 98.3 to 100%), but analys
is of secondary quality indicators reflecting times from first ED visit to
treatment in Epoch 3 raised the possibility that an adnexal mass or signs o
f tubal rupture may have been missed on some ED Sonos. We conclude that inc
reased availability of ultrasonography leads to improved quality in the det
ection of ectopic pregnancy in the ED, but at the expense of a disproportio
nate increase in the number of ultrasound studies done per ectopic pregnanc
y detected. Out study suggests that the most cost-effective strategy is for
emergency physicians to screen all patients with first trimester cramping
and bleeding with ED Sonos, and to obtain MI Sonos at the time of the initi
al ED visit in all cases in which the ED Sono is indeterminate or shows no
IUP.