5. TEACHING POINTS: UTERINE ASPIRATION PROCEDURE

EXERCISE 5.1

Purpose: To practice management of challenging situations that can arise at the time of aspiration abortion procedures.

  1. You are performing an abortion for an anxious 20-year old G1P0 patient at six weeks gestation. You complete the cervical block and have the tenaculum in place. As you attempt to introduce the smallest dilator, you are unable to advance the dilator through the internal os. After readjusting the speculum and the tenaculum, you again find that there is severe resistance as you attempt to advance the dilator into the cervical canal; it feels dry, gritty, and tight, and does not have the “normal” feel of the dilator tip advancing through the cervical canal.
    1. What is the differential diagnosis?
      • Acute flexion or tortuosity of the cervix
      • Congenital or acquired uterine abnormalities:
        1. Abdominal scarring due to prior (especially multiple) cesarean sections, which often limit adequate traction.
        2. Cervical stenosis from prior cone biopsy
        3. Fibroid in the lower uterine segment
        4. Müllerian anomaly
      • Error in assessment of uterine position (for example: the possibility of a sharply anteverted uterus with high cervix that may appear retroverted by visual exam without a thorough bi-manual exam).
      • False passage of the cannula due to any of the above.
    2. What would you do next?
      • See dilation tips from Steps for Uterine Aspiration of this chapter.
      • Consider having trainer or more experienced provider finish the procedure. Return to Exercises
  2. You have just completed an aspiration abortion for a 19-year old patient at six weeks gestation. They had reported intermittent episodes of vaginal bleeding on three occasions during the past week, but did not have any severe cramping or clotting. Their pre-procedure ultrasound was performed one week ago, with a 5 mm gestational sac identified, but no yolk sac or embryonic pole. Their pregnancy test was positive. Dilation was not difficult and you were able to use a 6 mm flexible cannula. The tissue specimen is very scant and you are not certain whether you see sac or villi.
    1. What is the differential diagnosis?
      • Spontaneous abortion since last ultrasound
      • Failed aspiration abortion
      • Completed aspiration abortion with POC too small to visualize
      • Ectopic pregnancy
    2. What do you do next?
      • An US prior to aspiration might have ruled out an early pregnancy loss since prior US, in which case aspiration could have been avoided.
      • Recheck POC, MVA, EVA bottles, tubing, cannula, and strainer, (if used).
      • Use a magnifier and backlighting if available.
      • Repeat US and reaspirate if tissue is still visible, with US guidance as indicated.
      • Consider using a different cannula, such as rigid curved cannula to follow flexion.
      • Consider an ectopic pregnancy in any case without definitive POC:
        1. Draw serial hCGs and give ectopic precautions.
        2. An hCG decrease of 50% within 48 hours suggests successful abortion (and is more reliable than US or pathology).
      • If free-floating villi are seen without any membranes present, consider the possibility of retained gestational sac, and repeat US.
      • If you see no villi, you can send the specimen to pathology. “Villi” on a pathology report confirms a pregnancy but not size estimation to confirm completion. Provider examination of POC reduces the risk of failed abortion, but routine histologic exam by a pathologist confers no incremental clinical benefit, and adds cost (Paul 2002).
  1. You are performing an abortion on a nulliparous 16-year old patient at seven weeks gestation. You notice that their cervix is very small and it is hard to choose a site for the tenaculum. As you put traction on the tenaculum and try to insert the dilator, the tenaculum pulls off, tearing the cervix. There is minimal bleeding, so you reapply the tenaculum at a slightly different site, although it is difficult because the cervix is so small. This time, the cervix tears after inserting the third dilator, and there is substantial bleeding.
    1. What should you do now?
    • These tears are fairly common, especially in small cervices. Try the following:
    • Before applying tenaculum to a small or flat cervix, inject several mLs of anesthetic to add bulk and facilitate placement (deeper in cervix, not in bleb).
    • Try a second tenaculum elsewhere on the cervix to provide a broader base of support, or an atraumatic tenaculum (pictured in Chapter 4 Paracervical Block image); then re-attempt dilation.
    • If bleeding, apply pressure to the cervix (clamp cervix with ring forceps or apply direct pressure). Dilute vasopressin (4-6 units in 5-10 cc sterile saline injected intra-cervically), Monsel’s solution, or silver nitrate may also be used; sutures are rarely required.
    • If unsuccessful, consider additional analgesia, misoprostol for 2–4 hours, delaying the procedure for a week to allow for more cervical ripening, or offering the patient medication abortion if eligible.
    • Consider pre-treatment with misoprostol in adolescents (WHO 2012) or those with a prior difficult dilation. Return to Exercises
  2. You are inserting the cannula for a procedure on a patient at 9 weeks gestation with a retroflexed uterus. Although the dilation was easy, you feel the cannula slide in easily but at a different angle and much further than you sounded with one of the dilators. You don’t feel any “stopping point.” The patient feels something sharp.
    1. What is the differential diagnosis?
      • A probable uterine perforation vs. a false tract.
    2. What should you do now?
      • Remove cannula. Evaluate for sharp or localized pain, vital signs, and bleeding.
      • US may assess fluid collection in the cul-de-sac, but in first trimester it is rare to be able to identify abdominal contents in the uterus, or uterine contents in the abdomen.
      • If the uterine cavity can be re-identified, an experienced provider may choose to finish the procedure under ultrasound guidance.
      • If vacuum has been applied, look for evidence of intra-abdominal contents (i.e. omental fat) in the aspirate. If seen, send to pathology and consider patient transfer.
      • If patient remains asymptomatic for pain or bleeding, consider observation for two hours, antibiotic coverage if appropriate (Paul 2009; p. 241), and precautions before discharge.
      • Consider uterotonics if bleeding is significant.
      • Hospitalization is indicated if:
        • The patient is hemodynamically unstable.  Place IVs and initiate IV fluid.
        • The patient has significant pain.
        • There is evidence of large perforation, laceration, expanding hematoma, fetal parts in abdomen, or viscera / omentum in uterus or aspirate.
    3. How might you have anticipated and prevented this problem?
      • Use gentle steady pressure during dilation until beyond the internal os.
      • Traction on the tenaculum helps straighten uterine flexion. Consider posterior placement for a retroflexed uterus to help straighten the angle.
      • Passage of a flexible uterine sound, os finder, or lacrimal duct probe may help to find the correct path, although use caution as a smaller instrument may increase perforation risk.
      • If your dilator passes easily but the cannula does not, consider using a smaller cannula or dilating one size higher.
      • Do not hesitate to re-check your pelvic exam.
      • Use US guidance, if available.
      • Consider a rigid curved cannula to maneuver the angle better.
      • Cervical ripening with misoprostol can be helpful.
  3. A G3P2 patient at 8w5d presents for termination, with a history of a previous cesarean and a post-partum hemorrhage not requiring transfusion. The aspirator quickly fills with blood when suction applied. You empty it, recharge, and it again fills with blood. You have seen some tissue come through. You ask your assistant to prepare another MVA but it promptly fills with blood when attached to the cannula. Given the patient’s risk factors, what additional preparations would you consider beyond normal precautions? 
    1. This patient is in the moderate risk category for hemorrhage (Kerns 2013). In addition to what you would do for a low risk patient (see Managing Immediate Complications Table), the following should also be considered:
      • Consider obtaining consent for transfusion.
      • Have uterotonic medications readily accessible.
      • Consider intraoperative ultrasound guidance.
      • With additional risk factors, you might also consider referring out to center with transfusion capability, anesthesia, and interventional radiology.
    2. What do you suspect?
      • The patient has already bled about 200 cc, and is at risk for hemorrhage (defined as 500 cc EBL).
      • Consider some causes of hemorrhage with 4 T’s mnemonic: tissue (incomplete aspiration), tone (atony), trauma (cervical laceration or perforation), or thrombin (a rare underlying bleeding disorder). Also consider ectopic pregnancy. Return to Exercises
    3. What can you do now?

As a memory tool, practice 2 primary steps for each of for 6Ts:

  • Tissue: Assure uterus is empty
    1. Estimate EBL
    2. Reaspiration (with US guidance) EVA for rapid evacuation; check POC is adequate. US may assist and identify the rare cervical or cesarean ectopic.
  •  Tone:
    1. Uterine massage
    2.  Medications (methergine, misoprostol, and / or dilute vasopressin)
  • Trauma: Assess source
    1. “Cannula test” (watching return as you slowly withdraw cannula from fundus to external os, to identify bleeding zone)
    2. Walk or clamp cervix with ring forceps
  •  Thrombin:
    1. Review bleeding history
    2. Consider additional tests as indicated (clot test, coagulation tests, CBC)
  •  Treatment:
    1. IV fluid bolus
    2. Uterine tamponade with Foley catheter (inflate bulb)
  •  Transfer:
    1. Vitals every 5 minutes
    2. Initiate transfer

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EXERCISE 5.2

Purpose: To practice managing challenges that may occur after uterine aspiration.

  1. The nurse consults with you about a possible problem phone call regarding a patient who had an abortion at the clinic five days ago. The patient complains of severe cramping and rectal pressure, has had minimal bleeding, and has a mild fever. 
    1. What is the differential diagnosis?
      • This patient may well have developed a hematometra, or accumulation of blood in the uterus following the procedure.
    2. Which exam and ultrasound findings would support your diagnosis?
      • Physical examination reveals a large, tense, and tender uterus.
      • US shows an expanded uterine cavity with heterogeneous echo complex, consistent with clots in the uterus.
    3. What are your management recommendations?
      • While small collections of clot may pass spontaneously or with uterotonics if patient’s pain is tolerable, aspiration is usually required for larger clots, with or without intraoperative uterotonics.
    4. If these symptoms developed immediately after abortion, what would you do?
      • Aspiration is usually required with or without uterotonics, and may save an ED visit.
  2. A 21-year-old patient comes to your office for follow-up after an 8-week abortion two weeks ago at another facility, and still has some symptoms of pregnancy including breast tenderness and abdominal bloating. Medications include birth control pills. The patient has had intercourse regularly for the past six days. The patient is afebrile, with normal vital signs. Pelvic exam is normal except for an 8-week size uterus. A high sensitivity urine pregnancy test is positive.
    1. What is the differential diagnosis?
      • A completed abortion in a patient with hormonal contraceptive side effects
      • A failed attempted abortion with an ongoing pregnancy
      • Retained POC / asymptomatic hematometra
      • Ectopic pregnancy or heterotopic pregnancy with continuing ectopic
      • Hydatidiform mole
    2. How can you rule in or out any of your diagnoses?
      • Home pregnancy tests are high sensitivity pregnancy tests (HSPT; positive at 20-25 mIU/mL) and can remain positive 4 – 6 weeks after abortion so a positive HSPT two weeks later may be positive for any of the differential diagnoses in this example.
      • Assess whether POC, post-abortion US, or an hCG were checked after the abortion, but a quantitative hCG is an important baseline for further testing.
      • Is serial serum hCG rising or falling, and at what rate? See Chapters 3 and 8.
      • US can help identify an ongoing pregnancy, remaining clots, or an ectopic pregnancy. However, a negative US is inconclusive and cannot definitively rule out an ectopic.
      • Exam may be helpful to evaluate uterine size, bogginess, or adnexal masses.
      • Re-aspiration determines uterine contents: presence of POC or pathologic changes.
      • Breast tenderness could be from hormonal contraceptives.
      • 8-week size could be due to fibroids, retained clots, or inter-examiner variability.
    3. How might your approach differ if the ultrasound showed a moderate amount of heterogeneous contents
      • This suggests retained tissue, decidua and/or clotted blood. Uterine re-aspiration may show evidence of chorionic villi, membranes, or fetal parts.
    4. If the patient is not pregnant, how can you explain their positive urine pregnancy test and breast tenderness?
      • A high sensitivity pregnancy test may still be positive for up to 4 – 6 weeks following an abortion.
      • Breast tenderness may be secondary to the initiation of hormonal contraceptives.

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