Wednesday 30 January 2013

Ectopic pregnancy



ECTOPIC PREGNANCY


Definition: a gestation that implants outside the endometrial cavity.
An ectopic pregnancy is estimated to occur in 1 of every 80 spontaneously conceived pregnancies
Site of implantation: 95% fallopian tube (including the ampullary 70-80%, isthmic 12%, infundibular and fimbrial 6-11% and interstiatial 2%) others less common site, ovary, uterine cervix and uterine horn
Risk factors:
History of tubal infection
Cigarette smoking (increased relative risk 1.26)
Prior ectopic pregnancy
History of tubal sterilization within the past 1 to 2 years (higher incidence if cauterization was used)
History of tubal reconstructive surgery
Pregnancy with current intrauterine device,  depot medroxyprogesterone acetate or emergency contraceptive pill use.
Infertility due to tubal factors
Use of assisted reproductive technology

Complication:
1.       Tubal rupture: with resulting intraperitoneal hemorrhage
2.       Pregnancy resorption: as a result of the restricted blood supply
3.       Tubal abortion into the peritoneal cavity

The classic triad of symptoms of ectopic pregnancy
1.       Prior missed menses( period of amenorrhea)
2.       Vaginal bleeding(2nd symptoms may present or may not present)
3.       Lower  abdominal pain(pain come first)

But it depends on if patient came with acutely ruptured ectopic pregnancy
-          severe abdominal pain and dizziness.
-           Ipsilateral shoulder pain
-          Hemodynamically innstabilty
-          Abdomen: distended and acutely tender with guarding and rebound tenderness
-          +ve cervical excitation
-          Slightly enlarged, globular uterus
(facilitate by UPT +ve and scan: empty uterus with free fluid in POD)

Differential diagnosis for ectopic preganancy
Gynaecology problem
Threatened  or incomplete abortion
Ruptured corpus luteum cyst
Acute PID
adnexal torsion
Degenerating fibroid(especially in pregnancy)
Non-gynae
Acute appendicitis
Pyelonephritis
Pacreatitis

Diagnostic test
1.       Serum BhcG
Healthy normal pregnancy usually the doubling time of BhcG in the serum varies from 1.2 days shortly after implantation to 3.5 days at 2 months after the last menstrual period
normal pregnancies show doubling of hcG levels every 48 hours in the first few weeks of pregnancy or at least 66% and the slowest range is 53%. Therefore, if hcG levels rises below 53%, diagnosis of abnormal IUP or ectopic pregnancy
2.       TVS
Although some IUP may be seen at lower level of hcG but every IUP should be visualized by the time the hcG reach the levels of so called discriminatory zone.
DZ defined as titer of hcG at which an IUGS should be seen by TVS.
On average 1500-2000mIU/ml for singleton pregnancy. So if above this level but no IUGS seen diagnostic of ectopic pregnancy



Inhomogeneous mass
 


 




Tubal
An empty endometrial cavity with:(1) an inhomogeneousadnexal mass or 
(2) anempty extra-uterine sac
or (3) a yolk sac or fetalpole _ cardiac activity in an extra-uterine sac


Interstitial   
An empty endometrial  cavity with products of 
conception located outside of the endometrial echo,
surrounded by a continuous rim of myometrium, within the
interstitial area.
 


Cervical 
 An empty endometrial cavity, with a gestational
sac present below the level of the internal os.
An absent ‘‘sliding sign’’and visible blood flow
around the gestation sac using colour Doppler.
  




Caesarean section scar
An empty endometrial cavity and cervical canal with a gestational
sac implanted within the lower anterior segment of uterine wall,
with evidence of myometrial dehiscence




 

    serum progesterone
Levels greater than 25ng/ml normal IUP and below 5ng/ml indicates abnormal pregnancy. But difficult to determine as most of the values usually falls on range between 5-25ng/ml

Management
        i.            Surgical management
Laparatomy vs laparascopic. If hemodynamically stable may choose laparascopic
Salpingectomy when there is significant damage to the tube
Partial salpingectomy is done only when ectopic pregnancy is implanted at mid-ampullary portion.
Salpingotomy and salpingostomy are both procedures in which the ectopic pregnancy is identified and vasoconstrictive agents are injected beneath the the implantation site prior to an incision. For salpingotomy the incision will be closed later.
      ii.            Medical management with MTX
Indications:
hemodynamically stable without active bleeding or signs of hemoperitoneum.
Patient desires future fertility
GA poses a significant risk
    iii.            Expectant management
Only if they are stable and the diagnosis of ectopic is not yet certain and the symptoms spontaneously resolving