Obstetric and Gynecologic Emergencies



Obstetric and Gynecologic Emergencies


Glenn Updike



I. Introduction

A wide variety of emergent obstetric and gynecologic issues lead women to seek care. This chapter outlines the pathophysiology, diagnosis, and management of the common obstetric and gynecologic conditions encountered by surgeons and emergency physicians.


Ectopic Pregnancy


I. Introduction

Ectopic pregnancies are those pregnancies that occur outside of the fundus of the uterus. While most ectopic pregnancies are in the fallopian tube, extrauterine pregnancies may also occur in the cervix, abdomen, cornua of the uterus, ovary, or in a previous cesarean scar. Rarely, an ectopic pregnancy may co-exist with a normal intrauterine pregnancy (a heterotopic pregnancy). Ectopic pregnancy can result in maternal morbidity or death. Prompt diagnosis and appropriate management, whether medical or surgical, is critical to prevent hemorrhage and its complications.


II. Incidence and Epidemiology



  • Approximately 20 per 1,000 pregnancies.


  • Most commonly occurs in the fallopian tube (98%).


  • Risk factors include:



    • Previous ectopic pregnancy. In a patient with a prior ectopic pregnancy, subsequent ectopic pregnancy occurs in 8% to 15%.


    • A history of tubal surgery including tubal ligation. Nearly 50% of pregnancies are ectopic in location after having tubal ligation.


    • Previously documented tubal pathology


    • In utero diethylstilbestrol exposure


    • Previous pelvic inflammatory disease (PID) or ruptured appendicitis


    • Infertility


    • Increasing number of lifetime sexual partners


    • Cigarette smoking


III. Diagnosis of Tubal Ectopic Pregnancy



  • The triad of a missed menstrual cycle, vaginal bleeding, and abdominal pain raises the suspicion for ectopic pregnancy.


  • The most common symptom is abdominal pain (greater than 95% of patients).


  • Physical examination may reveal abdominal tenderness or an adnexal mass. Rebound tenderness or guarding may be present.


  • Screen by using a urine pregnancy test.


  • When ectopic pregnancy is suspected, the patient should have a pelvic ultrasound by a sonographer experienced in gynecologic ultrasound.


  • The absence of an intrauterine gestational sac on transvaginal ultrasound with a corresponding serum hCG of greater than 1,500 mIU/mL should raise the suspicion for ectopic pregnancy.


  • An adnexal mass may be visualized by ultrasound with ectopic pregnancy. An adnexal gestational sac, yolk sac, and embryo may be visualized. There may be evidence of free fluid (blood) in the abdomen with ectopic pregnancy. The classic description of a tubal ectopic pregnancy on ultrasound includes a hyperechoic ring with surrounding vascular flow on Doppler, the so-called “ring of fire.”



  • If there is no extrauterine or intrauterine pregnancy visualized, order a serum quantitative hCG; if that serum hCG is less than 1,500 mIU/mL, repeat in 48 hours in the otherwise stable patient.


  • In a normal pregnancy, the serum quantitative hCG should approximately double every 48 hours. In rare circumstances, the 48 hour increase in serum hCG may be as low as 35%.


  • If the serum quantitative hCG is rising abnormally but it is unclear by ultrasound whether the pregnancy is extra- or intrauterine, a diagnostic dilation and curettage may be performed to assess for the presence of villi. The absence of villi and intermediate trophoblast cells on pathologic examination suggests the presence of an ectopic pregnancy. Additionally, following dilation and curettage the hCG should decline substantially within 24 hours with an intrauterine pregnancy, but will not decline significantly in the setting of an extrauterine pregnancy.


IV. Management of Tubal Ectopic Pregnancy



  • Expectant management



    • Reserved only for highly specialized circumstances.


    • Patients should be highly compliant with a documented falling quantitative serum hCG that is less than 1,000 mIU/mL.


  • Medical management



    • Also reserved for specialized circumstances in the compliant patient.


    • Absolute contraindications to medical management include:



      • Poor compliance


      • Hemodynamic instability


      • Medical contraindications to methotrexate therapy


    • Relative contraindications to medical management include:



      • Adnexal mass greater than 3.5 cm


      • Presence of embryonic cardiac activity


      • High quantitative hCG level. Success of single-dose therapy is lower in tubal ectopic pregnancies with a quantitative hCG level greater than 5,000 mIU/mL.


    • Therapy consists of the administration of methotrexate delivered as a single dose of 50 mg/m2.


    • The serum hCG is assessed on days 4 and 7 after administration.


    • If the serum hCG has not fallen by at least 15% between days 4 and 7, the patient may be given a second dose of methotrexate or offered surgical management after reassessment.


    • If the serum hCG decreases by 15% between days 4 and 7, the serum quantitative hCG should be assessed at weekly intervals until it is less than 20 mIU/mL.


    • Multi-dose treatment protocols for methotrexate are available for select patient with risk factors for failure of the single-dose regimen.


  • Surgical management



    • This remains the traditional management of ectopic pregnancy.


    • Laparoscopic approach is favored in most cases except in the setting of hemodynamic instability.


    • Options for surgical management include salpingostomy (the tubal pregnancy is removed through an incision in the fallopian tube) and salpingectomy (complete removal of the fallopian tube).


    • Patients undergoing salpingostomy must have serial assessment of the quantitative hCG post-operatively to ensure complete resolution of the pregnancy.


    • The relative benefits of salpingostomy as compared to salpingectomy with regard to future fertility are unclear.


Miscarriage


II. Introduction

Spontaneous abortion is defined as loss of the pregnancy prior to 20 weeks of gestation. When women experience bleeding during pregnancy, they often present to the emergency department for initial care. The term threatened abortion is used when there is vaginal bleeding in the first half of pregnancy and the cervical os is
closed. A missed abortion is a pregnancy in which there is embryonic demise or lack of progression of the pregnancy in the setting of a closed cervical os. Inevitable abortion is used to describe pregnancies in the first 20 weeks in which the cervix has begun to dilate or there is gross rupture of fetal membranes, but the pregnancy has not yet been expelled. Incomplete abortion refers to pregnancies in which the cervix has dilated and delivery of the fetus or placenta has begun, but products of conception remain in the uterus. This may be accompanied by heavy bleeding. Complete abortion refers to the passage of all products of conception and subsequent closure of the cervix.


II. Epidemiology and Pathophysiology



  • Fifteen percent of pregnancies end in spontaneous abortion.


  • Risk factors include advanced maternal age, previous miscarriage, and assisted reproductive technology.


  • Sixty percent of spontaneous abortions in the first trimester are the result of chromosomal anomalies.



III. Diagnosis



  • Patients may present with vaginal bleeding or cramping.


  • Physical examination may reveal blood in the vaginal vault. The cervix may appear dilated and the uterus is usually enlarged.


  • Gestational age by ultrasound may be inconsistent with the last menstrual period. Also, ultrasound may show an empty gestational sac or an embryo without a cardiac activity. On transvaginal ultrasound, cardiac activity should be noted in the embryo when the crown rump length is 5 mm, or by 5 to 6 weeks’ gestation.


  • A failed first trimester pregnancy is also likely when on transvaginal ultrasound, the mean gestational sac diameter exceeds 8 mm without visible yolk sac or when the mean gestational sac diameter exceeds 16 mm and without visible embryo.


  • Always assess for concomitant ectopic pregnancy with ultrasound.


IV. Management



  • No therapy is effective in the prevention of miscarriage during threatened abortion. Pelvic rest and limitation of activity does not decrease the chance of spontaneous abortion.


  • Patients who are not bleeding heavily, are hemodynamically stable, and not in excessive pain can be managed expectantly.


  • Medical management with drugs such as misoprostol and mifepristone can aid resolution of early pregnancy failure.


  • Dilation and curettage is the treatment for patients who are bleeding heavily, are hemodynamically unstable, or unwilling to undergo expectant or medical management.


  • All patients who have bleeding during pregnancy should have a blood type and antibody screen. In patients who are Rh negative and bleeding during the first trimester, administer anti-D immune globulin.


Third Trimester Bleeding


I. Introduction

During the third trimester, uterine blood flow has increased to over 500 cc/min. As such, a variety of pathologic states involving the placenta and uterus can result in massive blood loss in a short period of time. Prompt recognition and appropriate resuscitation are critical in prevention of serious morbidity and mortality from obstetric hemorrhage in the third trimester.


II. Placental Abruption



  • Refers to the state in which all (complete abruption) or part (partial abruption) of the placenta separates from the uterus after 20 weeks’ gestation but prior to delivery.


  • Incidence is 0.4% to 1% of pregnancies, with 80% occurring prior to the onset of labor.



  • Fetal and neonatal morbidity and mortality associated with placental abruption are linked with preterm birth, low birth weight, and fetal distress


  • Risk factors include trauma, hypertension, cocaine use, thrombophilias, preterm premature rupture of membranes, rapid decompression of amniotic fluid, and cigarette smoking.


  • Results from disruption of maternal vessels in the decidua basalis where they interface with the villi of the placental cytotrophoblast. May result from trauma or a chronic pathologic vascular process.


  • Most common presentation is vaginal bleeding, although 20% of patients will not exhibit bleeding. Half of patients will present with abdominal pain and uterine contractions.


  • Physical examination may reveal a rigid, firm uterine fundus.


  • The fetal heart tracing may have signs of fetal distress.


  • Ultrasound may show a retroplacental hematoma, but the sensitivity of ultrasound in detection of placental abruption is poor.


  • If massive bleeding is present, clinical and laboratory evidence of disseminated intravascular coagulation may be associated.


III. Placenta Previa



  • Placenta previa refers to the implantation of the placenta over the cervical os. This may be complete (entirely covering the cervical os), partial (only a portion of the placental covers the cervical os), or marginal (the placenta approaches but does not cover the cervical os).


  • Placenta previa complicates 1 in 200 pregnancies.


  • Risk factors include placenta previa in a prior pregnancy, previous cesarean delivery or other uterine incision, and advanced maternal age. Previous cesarean section remains the most important risk factor for development of placenta previa, with the risk increasing with the number of previous cesarean sections.


  • The classic presentation of placenta previa is painless vaginal bleeding. All patients presenting with vaginal bleeding in pregnancy should have ultrasound imaging to determine the location of the placenta.


  • DO NOT perform digital examination of the cervix in patients with placenta previa—this could precipitate hemorrhage.


IV. Management of Third Trimester Bleeding



  • Third trimester bleeding is an obstetric emergency. Maternal hemodynamic status should be monitored closely and fetal status should be assessed with continuous fetal heart rate monitoring.


  • Two large-bore intravenous lines should be placed to allow rapid replacement of any lost intravascular volume.


  • If blood loss is large, ongoing, or associated with hypotension, transfuse early with packed red blood cells.


  • In addition to measurement of hemoglobin, platelet count and blood type assess coagulation status with measurements of the prothrombin time, activated partial thromboplastin time, and fibrinogen. Coagulopathy should be corrected with fresh frozen plasma or cryoprecipitate as necessary.


  • When maternal hypovolemia, coagulopathy, or nonreassuring fetal heart rate status exist, expedite delivery to prevent maternal and fetal morbidity. Delivery is always by cesarean section for placenta previa and abruption.


Labor and Delivery


I. Introduction

Not infrequently, women present in the advanced stages of labor, and movement to the labor and delivery suite for delivery may not be possible. Basic aspects of labor and delivery are reviewed in the following.


II. Normal Labor

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Oct 17, 2016 | Posted by in CRITICAL CARE | Comments Off on Obstetric and Gynecologic Emergencies

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