Emergency Medicine

GYNAECOLOGICAL CAUSES OF ACUTE ABDOMINAL PAIN

Obstetric and Gynaecological Emergencies 377

Ruptured ectopic pregnancy

DIAGNOSIS

1 Ectopic pregnancy is more common in patients with a previous ectopic pregnancy,
pelvic inflammatory disease, previous tubal surgery, assisted reproductive tech -
niques, and in patients using an intrauterine contraceptive device (IUCD).
(i) However 50% occur with no predisposing risk factors.

2 Ectopic pregnancy usually presents from the 5th to the 9th weeks of preg-
nancy. Patients may not realize they are pregnant, although they may give a
history of breast tenderness, nausea or recent unprotected intercourse.
(i) Consider an ectopic in every female patient with menstrual
irregularities, vaginal bleeding, lower abdominal pain or collapse.

3 The predominant feature on history is lower abdominal pain, which is
present in over 90% of presentations. Vaginal bleeding is usually mild.

4 Haemodynamically unstable patient:
(i) Unstable patients present with sudden abdominal pain, often
referred to the shoulder tip, followed by scanty vaginal bleeding,
proceeding to circulatory collapse and haemorrhagic shock.
(ii) On examination the patient is pale, collapsed and hypotensive
with a tender, rigid silent abdomen.

5 Haemodynamically stable patient:
(i) Stable patients present with a recent history of a missed period
or sometimes erratic periods, lower abdominal pain and slight
vaginal bleeding that is typically dark brown (‘prune juice’),
although the bleeding can be fresh red.
(ii) There is localized lower abdominal tenderness and guarding
to one side, and a smaller uterus than expected on bimanual
palpation for the duration of apparent amenorrhoea.

6 Perform a pelvic examination.
(i) Be gentle to avoid the potential for traumatic tubal rupture.
(ii) Examine for discomfort and swelling in the lateral fornix.

7 Insert one or two large-bore i.v. cannulae and send blood for full blood count
(FBC), urea and electrolytes (U&Es), blood sugar, and group and save (G&S).
Note the rhesus status.

8 Perform a pregnancy test.
(i) A serum radioimmunoassay pregnancy test for -hCG in blood is
highly sensitive, with a negative test ruling out a recent ectopic or
miscarriage, although it takes time to do and may not be available
after hours.
(ii) Alternatively, test for urinary -hCG. This urine dipstick test can
be done rapidly in the emergency department (ED), and may be
positive even before the first missed period. Again, a negative test
virtually rules out an ectopic.