Pregnancy, Ectopic

Implantation of a fertilized oocyte outside the uterine cavity.

1.3–2.4% of all pregnancies, but rate is increasing due to risk factors and better diagnostic methods.

Risk factors: High-tubal surgery, prior ectopic pregnancy, use of an IUD, interutero exposure to diethylstilbestrol, moderate assisted reproductive technologies, pelvic inflammatory disease, smoking, tubal pathology; maternal age >40 y.

Fallopian “tubal” pregnancy is most common (97–99%).

Leading cause of pregnancy-related maternal deaths in first trimester; 4–10% of all pregnancy-related deaths.

Mortality rate has declined from 1.15 to 0.5 maternal deaths per 100,000 live births owing to improved detection and treatment. Deaths are 6.8 times more common among African Americans and 3.5 times more common among women >35 y.

Highest mortality with intraabdominal and interstitial tubal pregnancies because of increased fetal size, blood flow, and subsequent tissue involvement.

Death principally due to hemorrhage, shock, and renal failure

Blood availability; may need type-specific or O-negative blood

Full-stomach/aspiration risk

Physiologic changes of pregnancy (see Pregnancy, Intra-Abdominal )

Effects of CO ₂ insufflation and steep Trendelenburg position on ventilation in the case of laparoscopy

Primary concerns for airway, intravascular volume, and blood/coagulation management.

Approach similar to that in the case of a trauma pt with profound hypovolemia.

Dx made by history, physical (pelvic pain, 95%; amenorrhea, 75%; uterine bleeding, 60–80%); β-hCG (higher sensitivity of radioimmunoassay method) and ultrasound. 70% are diagnosed prior to rupture.

Differential Dx: Appendicitis, any intraabdominal infection or process.

Mechanical factors: Salpingitis, peritubal adhesions, previous ectopic, prior tubal surgery, multiple prior abortions

Functional factors: External ovum migration, menstrual reflux, altered tubal motility