Makindo Medical Notes.com

An ectopic pregnancy must be suspected in any woman with a positive pregnancy test, amenorrhoea and abdominal or pelvic pain or PV bleeding, as delayed or misdiagnosis can be fatal.

About

• The Commonest cause of maternal death in the first trimester
• Suspect in any woman with a positive pregnancy test, amenorrhoea and pelvic pain or PV bleeding.
• A positive β-HCG plus an empty uterus and an adnexal mass on Ultrasound are the classic signs.
• Digital vaginal exam should be deferred until resuscitation facilities are at hand as it may provoke a rupture
• In a normal pregnancy, serum β-HCG doubles every 2 days

Aetiology

• Ectopic pregnancy is defined as a pregnancy that is not normally positioned in the uterine cavity.
• It is seen in 1 in 200 pregnancies and incidence increases with maternal age.
• A positive pregnancy test and an empty uterus on scanning strongly suggests the diagnosis of ectopic pregnancy.
• The Commonest site to implant is the ampullary region of the fallopian tube

Physiology

• Fertilisation i.e., the sperm entering the ovum occurs within the uterine (fallopian) tubes.
• The fertilised egg must then pass down the tubes into the uterine cavity where it implants.
• Any defect due to scarring or infection predisposes to failure of this passage and implantation outside the uterus.

Risk of ectopic increases with

• Previous ectopic pregnancy
• Previous PID or IUCD or Endometriosis
• Previous abdominal/pelvic surgery
• Previous sterilisation reversal
• In vitro fertilisation / GIFT
• Ovarian/Uterine cysts or tumour s

Classical clinical features pre-rupture: Pain and PV bleeding

• Amenorrhoea, usually 5-8 weeks post LMP
• Unilateral Lower abdominal pain - in either side
• Vaginal bleeding - "prune juice appearance" in 1st trimester
• Rupture can lead to haemorrhagic shock or syncope.
• Vasovagal episodes

Investigations

• Urine β-HCG only positive in 50% need to do serum β-HCG - repeated levels. Serial levels may be needed if no sac is viewed on ultrasound, and usually doubles every 48 hours. In an ectopic pregnancy, the levels fail to rise.
• Ultrasound can confirm an extrauterine pregnancy or show free fluid in the pouch of Douglas. A transvaginal scan may be needed if the test is negative.
• Transvaginal USS - shows empty uterus, adnexal tubal sac, free fluid
• Rhesus status - should be checked as anti-D immunoglobulin may be required
• Laparoscopy is definitive procedure
• Clotting may be assessed if there is concern about DIC

Differential

• Acute appendicitis
• Acute PID

Management

• ABCs and resuscitation as needed. Blood cross-matching x6 units, IV Cannulas x 2, emergency laparotomy and salpingotomy or salpingectomy. If stable enough then laparoscopic surgery may be considered
• Laparoscopic surgery should be considered as a first-line treatment option when the woman has significant pain, adnexal mass is 3.5 cm or larger, a fetal heartbeat is visible on ultrasound scan and/or serum hCG is 5000 IU/L or more.
• Medical treatment with IM Methotrexate useful in selected patients, e.g. a sac < 4 cm and a β-HCG < 1500 iu/L. The β-HCG is monitored at intervals following methotrexate. It may avoid surgery with its inherent dangers, especially haemorrhage with cervical, interstitial or intramural pregnancies
• A choice of either using Methotrexate or surgical management should be given to women when asymptomatic, with an adnexal mass of less than 3.5 cms and serum hCG levels between 1500 IU/L to 5000 IU/L. (NICE guidelines 154 December 2012)
• Conservative or expectant management of ectopic pregnancy should only be considered in women that are asymptomatic, with hCG levels less than 1000 IU/L and a small adnexal mass of 2 cms or fewer. Again, the success of treatment depends on the level of support and counselling provided to women.
• When using medical and expectant management of an ectopic pregnancy, follow up for patients in EPAU till serum hCG is negative. The drop in serum hCG levels should be at least more than 15% every visit for conservative management to succeed
• Anti-D rhesus prophylaxis at a dose of 250 IU should be offered to all rhesus negative women who have a surgical procedure to manage an ectopic pregnancy or miscarriage.