Operative Procedures - Vacuum Aspiration

As with all operative procedures, sound principles of surgical technique and the prevention of complications should include

• accurate preoperative diagnosis and evaluation;
• high level of operator skill;
• sound sterile technique;
• atraumatic surgical technique;
• thorough removal and identification of tissue; and
• careful postoperative supervision and follow-up.

An intravenous infusion should be started prior to the procedure. Prophylactic intraoperative oxytocin administration has not been shown to reduce blood loss in gestations less then 15 weeks. The awake patient should be informed prior to every action so that she has realistic expectations, especially with painful events (injections, grasping of the cervix, dilatation, and vacuum aspiration).

Procedures
1. Induction of conscious sedation or general anaesthetic.

2. The patient is prepared and draped in the lithotomy position. The gauze and osmotic dilator are removed.

3. A bimanual examination is performed to assess uterine position and size.

4. A speculum is inserted and the cervix visualized.

5. When conscious sedation is used, the anterior lip of the cervix is injected with 2 mL of local anaesthetic solution.

6. The anterior lip of the cervix is grasped with atraumatic forceps or a tenaculum.

7. A paracervical block is performed using 10 mL of 1% lidocaine injected deep into the lower uterine segment where each uterosacral ligament attaches (between 4 and 5 o'clock on one side, and 7 and 8 on the other side), followed by deep injection around the cervix at 2, 3, 9, and 10 o'clock up to a total of 20 mL (up to 4.5 mg/kg) of anaesthetic solution for the entire procedure.

8. There should be a delay of three to four minutes prior to dilatation.

9. To decrease pain, the cervix should be slowly and gently dilated with tapered dilators, e.g., Pratt's dilators. It is suggested the cervix be dilated to a number 27 Pratt dilator up to 8 weeks' gestation, number 31 to 33 up to 10 weeks' gestation, and 37 to 39 up to 12 weeks' gestation. These recommendations are dependent on the size and firmness of the cervix as well as the prior use of misoprostol or osmotic dilators. A survey of providers found that 50% dilate the cervix to a diameter in millimetres corresponding to the GA, and an additional 36% dilate one to two millimetres above the GA.

10. During dilatation, the awake patient is informed that she will experience menstrual type cramps. Working slowly will decrease the patient's discomfort.

11. Vacuum aspiration is then performed. Repeated trauma and suction within the internal os should be avoided. The greatest discomfort occurs when the suction curette is pulled through the internal os.