is necessary because definitive treatment may require taking the patient to
the OR to relieve the obstruction. An old surgical adage states “Never let
the sun set or rise on a bowel obstruction.” Broad-spectrum antibiotics
(b and d)are appropriate when surgery is planned or when there is suspi-
cion for vascular compromise or bowel perforation.
Stool softener and enemas (c)have no role in acute intestinal obstruc-
tions caused by mechanical causes. Adult SBO are diagnosed with an
abdominal plain film, or CT scan (e),not by ultrasound.
101.The answer is b.(Rosen, pp 1176-1185.)The patient’s presentation is
worrisome for an AAA. If the patient was hemodynamically unstable, he
should be brought immediately to the OR for definitive repair. However, in
thestablepatient, imaging studies can aid in the diagnosis of an AAA.
Ultrasoundis almost 100% sensitivein detecting AAA, it is noninvasive,
and can be performed rapidly at the patient’s bedside. If the entire abdom-
inal aorta is visualized and found to be of normal diameter, it is safe to say
that the patient’s symptoms are not from an AAA. An alternative to ultra-
sound in the stable patient is a CT scan, which is essentially 100% accurate
in determining the presence of an AAA. The CT scan is less subject to tech-
nical and interpretation errors than an ultrasound.
(a)Angiography has no role in the early diagnosis of an AAA. Often
the lumen of the aorta is narrowed by mural thrombus, but appearing
falsely normal. (c)MRI is often used to follow the growth of a known AAA
over a period of months or years. (d)An enlarged calcific aorta can some-
times be detected by plain abdominal radiograph; however, the sensitivity
is low. (e)D-dimer is not an established marker in the diagnosis of an AAA,
but may be considered a first step in the management of low probability
deep venous thrombosis (DVT) and pulmonary embolism (PE) patients.
102.The answer is c.(Rosen, pp 2416-2419.)Any woman with abdomi-
nal pain, vaginal bleeding, and a positive pregnancy test needs to be ruled
out for an ectopic pregnancy.Her vital signs are stable so that she can
undergo a transvaginal ultrasound.This is used to document an intrauter-
ine pregnancy and the health of the fetus. If no intrauterine pregnancy is
observed, the suspicion for an ectopic pregnancy increases.
(a)Laparoscopy is an accurate diagnostic and therapeutic procedure
that can be used in the patient with an unclear ultrasound and peritoneal
signs on examination.(b)If an intrauterine pregnancy is documented and
there is low suspicion for an ectopic pregnancy, yet the patient complains
Abdominal and Pelvic Pain Answers 117