First Trimester Uterine Aspiration

Module

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Objectives

By the end of this unit, you should be able to:

• List the equipment and supplies needed for uterine aspiration with the manual vacuum aspirator (MVA) and electric vacuum aspirator (EVA)
• Summarize the steps of uterine aspiration, or suction dilation and curettage (D&C)
• Explain the possible complications of uterine aspiration

Uterine Aspiration Indications

• Induced abortion or miscarriage management up to 13 weeks
  • Evacuation of molar pregnancy
  • Treatment of retained products of conception or hematometra

• Methods
  • Manual vacuum aspiration (MVA) • Electric vacuum aspiration (EVA)

Choosing a Method

Manual Vacuum Aspiration

• Outpatient setting is OK
• No electricity needed
• Less noise
• Syringe is inexpensive, reusable
• May need more passes at later estimated gestational age (EGA)

Electric Vacuum Aspiration

• Outpatient setting is OK
• Requires suction machine
• More noise
• Consistent, unlimited suction

Equipment Needed

• Speculum
• Cleansing solution
• Gauze
• Ring forceps for cleansing cervix and removing tissue from the cervix/vagina as needed
• Lidocaine
• 10-20 mL syringe with 22 gauge needle extender for paracervical block
• Tenaculum: Placed on anterior or posterior lip to straighten canal and provide counter-traction for dilation

Dilators

• Tapered dilators are preferred
  • Denniston
  • French Pratt
• Dilate to mm equals gestational age
• 1 French refers to the circumference of a dilator
• French system/3 = mm

Cannula

• Rigid or flexible
• Provider preference
• Generally, use cannula with diameter equal to or 1 mm greater than estimated gestational age

Aspirator

• Manual
• Electric

Electric vacuum aspirator.

Pre-evaluation for Uterine Aspiration

• Informed consent
  • Risks and alternatives
• Rh Testing
  • RhoGAM required for Rh-negative patients
• Antibiotic prophylaxis
  • Several regimens acceptable
  • Should be initiated prior to procedure
  • Example: 30 minutes prior
    • Doxycycline 100mg
    • Azithromycin 500mg
• Discussion of contraceptives
  • Consider immediate post-abortion placement of long-acting acting reversible (LARC)
    • Intrauterine Device (IUD)
    • Implant
• Testing for sexually transmitted diseases (STDs)
  • Per Centers for Disease Control and Prevention (CDC) guidelines: http://www.cdc.gov/std/
  • May treat at time of procedure
  • Delay of procedure for treatment is not necessary
• Anemia
  • Evaluate for anemia if active/heavy bleeding

Uterine Aspiration Steps

1. Assemble all materials
2. Conduct “timeout”
3. Bimanual exam for size/position of uterus
4. Insert speculum and prep cervix with iodine or alternative in case of allergy
5. Place tenaculum
   • Inject 2ml lidocaine at planned tenaculum site
   • Good purchase to anterior or posterior lip
   • Close ratchets slowly to lessen pain
   • Exert gentle traction on cervix for dilation and manipulate cervix to administer paracervical block
6. Paracervical block
   • Numerous regimens
     • 10-20 ml of 0.5-1% lidocaine
     • Plain or with vasoconstrictor
       • Vasopressin: less tachycardia than epinephrine
     • Evidence-based blocks
       • 20 mL buffered lidocaine total
       • 2mL at tenaculum site
       • Continuous injection in and out to 3 cm of 18ml at 2 or 4 sites at cervico-vaginal junction (2 o’clock, 4 o’clock, 8 o’clock, and 10 o’clock)

     

   • Lidocaine toxicity
   • 4mg/kg plain lidocaine
   • 7mg/kg with vasoconstrictors
   • Example: 1% lidocaine is 10mg/mL
     • 70 kg, max 1% plain lidocaine = 28mL
7. Dilate cervix
   • Hold dilator loosely using tapered dilator
   • Redirect dilator if significant resistance
   • Dilation goal: Allow passage of cannula whose diameter correlates with EGA in weeks
   • 1 French refers to the circumference of a dilator
   • French system/3 = mm (e.g., Size corresponding to 9 weeks’ EGA  9mm (+/- 1mm) cannula; 27 French/3=9mm) 

All steps apply to both MVA and EVA unless specified.

Cervical Dilation

Types of Dilators

• Pratt (metal, tapered ends)
  • Diameter measured in French (=0.33 mm)
  • Example: 21 French = 7 mm
• Denniston (plastic, tapered ends)
  • Diameter measured in mm
• Hegar (metal, more blunt ends)
  • Diameter measured in mm

Uterine Aspiration Steps

This step for MVA only.

8. Prepare MVA syringe
   • Attach cannula
   • Close (compress) valve
   • Pull back plunger

   

    

   • Attach appropriate tubing
     • Small caliber: size 6-12 cannula
     • Large caliber: size 14-16 cannula
   • Test suction: Adjust to 40-60 mm Hg
9. Select cannula
   • Typically gestational age (GA) or GA + 1 mm
10. Inserts cannula, performs curettage
    • MVA: release valves once inserted
    • Electronic: insert or remove cannula with suction off
11. Uterine aspiration
    • Rotation combined with gentle in and out motion
    • Ultrasound may be used
    • Rotate until signs the uterus is empty
      • “Crie,” gritty texture
      • More difficulty moving the cannula as uterus collapses
    • Sharp curettage not routinely necessary
12. Complete procedure
    • Remove tenaculum
    • Apply hemostatic treatment if needed
    • Assess for uterine bleeding
    • Remove speculum
13. Examine tissue to ensure gestational sac is present
    • Strain and rinse the tissue
    • Place tissue in a clear container
    • It is recommended to use a backlight to inspect the tissue

Products of Conception

Examining the products of conception can:

• Assure successful removal of pregnancy
• Confirm estimated gestational age
• Provide evidence of abnormal pregnancy

Complications

• Hemorrhage: treat with uterotonic agents
• Infection: consider retained products
• Uterine perforation from dilators or vacuum cannula
• Retained products of conception

Postoperative Care

• Observation
  • Observe patient for at least 30 minutes o Monitor for complications related to bleeding
• RhoGAM if Rh-negative
• What to expect after discharge
  • Cramping can be normal for up to a few days (mild)
  • Bleeding should be no heavier than period
  • Severe symptoms warrant evaluation
• Consider immediate post-abortion placement of long-acting acting reversible (LARC): IUD or implant

Conclusions

• First trimester uterine aspiration is safe
• Following appropriate steps helps to ensure safety of the procedure
• Complications are rare but must be recognized

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Author

• Anne Burke, MD, MPH Associate Professor of Gynecology and Obstetrics Johns Hopkins University School of Medicine

Developed in association with Society of Family Planning.

Version 2.0, reaffirmed March 2017