Surgical techniques of uterine evacuation in first- and second-trimester abortion

Abstract

Induced abortion is an ancient procedure. Vacuum curettage is a recent innovation and is demonstrably superior to other methods for first-trimester abortions. Patient selection, patient preparation and the necessary instruments are described. The only absolute contraindications for local anaesthesia, vacuum curettage abortions are pregnancies too far advanced and allergy to local anaesthestics. The only mandatory laboratory tests are Rh blood group and cervical culture for gonorrhoea. Rh-negative patients must receive anti-D (Rh0) immunoglobulin. Perioperative antibiotics are of proven benefit. The technique of first-trimester vacuum curettage is described in detail here. The technique for very early abortion with the Karman cannula is also described. Fresh examination of tissue is critical after any abortion in order to rule out incomplete or missed abortion and to detect ectopic or molar pregnancy. Management of suspected perforation, haemorrhage, post-abortal syndrome and failed abortion are described. Dilation and evacuation (D&E) is the safest technique for mid-trimester abortion, especially when performed at 13-16 weeks. Some mid-trimester techniques are reviewed and the technique we follow is described in detail. Laminaria tents are left in place overnight, and the procedure is performed under paracervical block with intravenous sedation using low doses of diazepam and fentanyl. Evacuation is by means of large-bore vacuum cannula system and large ovum forceps. General anaesthesia is avoided because it increases the risk of perforation and haemorrhage. Adjuncts to D&E are described: intraoperative real-time ultrasound, intracervical vasopressin, two days' treatment with laminaria tents, and Hern's technique combining laminaria with intra-amniotic infusion of urea prior to D & E.