CHAPTER 6 TEACHING POINTS: UTERINE ASPIRATION PROCEDURE
EXERCISE 6.1
Purpose: To practice management of challenging situations that can arise at the time of aspiration abortion procedures.
- You are performing an abortion for a 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.
- What is the differential diagnosis?
- Acute flexion or tortuosity of the cervix
- Congenital or acquired uterine abnormalities:
- Abdominal scarring due to prior (especially multiple) cesarean sections, which often limit adequate traction.
- Cervical stenosis
- Müllerian anomaly
- Fibroid in the lower uterine segment (unlikely in this age group)
- Error in assessment of uterine position (e.g possible sharply anteverted uterus with high cervix that may appear retroverted by visual exam without a thorough bimanual).
- False passage of the cannula due to any of the above.
- Cervical scarring from prior procedures (colpo, LEEP unlikely in this age group)
- What would you do next?
- See dilation tips from Steps for Uterine Aspiration of this chapter.
- Ask for ultrasound guidance.
- Consider having a more experienced provider assist with dilation or finish the procedure–(may require returning another day) –or convert to medical abortion.
- How might you respond to the patient’s request for a break due to pain?
- What is the differential diagnosis?
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- As much as possible, give the patient control and keep them informed.
- If the patient asks to stop, then stop.
- Check in about whether they want additional pain management.
- Ask if they want physical or emotional support during the procedure.
- Consider adding “Let me know when you are ready to proceed.”
- Keep them informed if you need to consider additional steps for safety, including a discussion of risks if procedure can not be completed today.
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- You have just completed an aspiration abortion for a 19-year-old patient at six weeks gestation. Their pre-procedure ultrasound shows a 5 mm fluid collection, 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.
- What is the differential diagnosis?
- Failed or incomplete aspiration abortion
- Completed aspiration abortion with POC too small to visualize
- Ectopic pregnancy
- What do you do next?
- What is the differential diagnosis?
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- Recheck POC, MVA, EVA bottles, tubing, cannula, and strainer (if used).
- Use a magnifier and backlighting if available.
- Repeat US.
- Reaspirate if tissue is still visible, with US guidance as indicated.
- Consider using a different cannula, such as rigid, curved cannula to follow flexion.
- Rule out an ectopic pregnancy in any case without definitive POC:
- Draw serial hCGs and give ectopic precautions.
- 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 may send the specimen to pathology. “Villi” on a pathology report confirms a pregnancy but not completion. Provider examination of POC reduces the risk of failed or incomplete abortion. Routine histologic exam by a pathologist confers no incremental clinical benefit, and adds cost (Paul 2002).
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- 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 small. This time, the cervix tears after inserting the third dilator, with substantial bleeding.
- What should you do now?
Try the following:
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- 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, an atraumatic tenaculum (pictured in Chapter 5 Paracervical Block image); then re-attempt dilation.
- If bleeding, apply cervical pressure (direct pressure or clamp cervix with ring forceps). Inject dilute vasopressin (4-6 units in 5-10 cc sterile saline intra-cervically), Monsel’s solution, or silver nitrate may also be used; sutures are rarely required.
- Offer medication abortion, if eligible.
- Consider misoprostol in adolescents or those with a prior difficult dilation.
- If unsuccessful, consider additional analgesia, misoprostol for 2–4 hours, delaying the procedure for a week to allow for more cervical ripening
- 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.
- What is the differential diagnosis?
- A probable uterine perforation vs. a creation of false passage.
- What should you do now?
- Immediately stop suction and gently 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 US guidance.
- If vacuum has been applied, look for evidence of intra-abdominal contents (i.e. omental fat) in the aspirate. If seen, this confirms perforation. Any evidence of intra-abdominal contents necessitates transfer to higher level of care.
- If patient remains asymptomatic for pain or bleeding, consider observation for two hours, antibiotic coverage (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 any viscera / omentum in uterus or aspirate.
- 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 or os finder 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.
- What is the differential diagnosis?
- A G3P2 patient at 8w5d presents for an abortion, with a history of a previous cesarean and a postpartum hemorrhage not requiring transfusion. The aspirator quickly fills with blood when suction is 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.
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- Given the patient’s risk factors, what additional preparations would you consider beyond normal precautions?
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 ultrasound guidance.
- With additional risk factors, if possible, you might also consider referring to a center with transfusion capability, anesthesia, and interventional radiology.
- 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 4T’s mnemonic: tissue (incomplete aspiration), tone (atony), trauma (cervical laceration or perforation), or thrombin (a rare underlying bleeding disorder). Also consider ectopic pregnancy.
- What can you do now?
- Given the patient’s risk factors, what additional preparations would you consider beyond normal precautions?
As a memory tool, practice 2 primary steps for each of the 6T mnemonic of management:
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- Tissue: Assure uterus is empty
- Estimate EBL
- Reaspiration (with US guidance) EVA for rapid evacuation; check POC is adequate. US may assist and identify the rare cervical or cesarean ectopic.
- Tone:
- Uterine massage
- Medications (methergine, misoprostol, dilute vasopressin, tranexamic acid
- Trauma: Assess source
- “Cannula test” (watching return as you slowly withdraw cannula from fundus to external os, to identify bleeding zone)
- Walk or clamp cervix with ring forceps
- Thrombin:
- Review bleeding history
- Consider additional tests as indicated (clot test, coagulation tests, CBC)
- Treatment
- IV fluid bolus
- Uterine tamponade with Foley catheter or Bakri balloon (inflate bulb)
- Transfer
- Vitals every 5 minutes
- Initiate transfer
- Tissue: Assure uterus is empty
EXERCISE 6.2
Purpose: To practice managing challenges that may occur after uterine aspiration.
- 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.
- What is the differential diagnosis?
- This patient may have developed a hematometra, or accumulation of blood in the uterus following the procedure.
- Undetected perforation with possible bowel injury
- 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.
- What are your management recommendations?
- While small collections of clot may pass spontaneously or with uterotonics if the patient’s pain is tolerable, aspiration is usually required for larger clots, with or without intraoperative uterotonics.
- 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.
- What is the differential diagnosis?
- 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.
- 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
- Uterine fibroids causing enlarged uterine size
- Ectopic pregnancy or heterotopic pregnancy with continuing ectopic
- Hydatidiform mole
- 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 Chapter 3, Serial Serum hCG Levels.
- 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.
- 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.
- 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.
- What is the differential diagnosis?