If a third-degree tear occurs in hospital, it is usually repaired immediately. If it occurs elsewhere, a patient may present too late for an immediate repair. Or a tear which has been sutured immediately may break down, and need repair later. Sometimes, a tear epithelializes and heals itself. If it is not very extensive, and her levator ani muscles are little damaged, she may not want the operation, and only be incontinent of faeces when her stools are very loose.
Fig. 18-17 REPAIRING A THIRD-DEGREE TEAR. A, a recent tear, B to T, an old one. From Parsons and Ulfelder, ''Atlas of Gynaecological Surgery', pp. 259 and 261. W.B. Saunders, with kind permission.
AN OLD THIRD-DEGREE TEAR This is more difficult than the repair of a fresh tear. If possible, refer her. Don't operate for at least three months after delivery, or the last attempt to repair it, because her tissues will still be oedematous and infected.
PREOPERATIVE PREPARATION. Give her a low-roughage diet for 2 days, and then an enema preoperatively.
ANAESTHESIA. Give her a saddle block (A 7.7), or an epidural block (A 7.2), or a general anaesthetic.
INSTRUMENTS. Use those listed in the previous section for a recent tear. A good light, plenty of swabs (she will bleed), an assistant, and a scrub nurse.
METHOD. The patient in B, Fig. 18-17 has torn her perineal body. Cut round her exposed mucous membrane for the full thickness of her vaginal skin. Apply Allis forceps, and use scissors to gently separate her vaginal wall from her rectum (C).
While you exert gentle tension on her vaginal wall, dissect laterally and free her rectum anteriorly and on both sides (D). Apply clamps to the cut edges of her vaginal skin, and hold them downwards. Extend the dissection upwards in the plane of cleavage between her rectum and her vagina, holding your scissors against her posterior vaginal wall (E).
Incise her vaginal wall in the midline (F), to expose her rectum (G). Hold her rectum medially, and use the handle of your scalpel to extend the plane of cleavage between the vaginal flap and her rectal wall (H). If you can mobilize her rectum, you can close it without tension.
Trim the remaining scar tissue from the edge of her rectal mucosa (I). Hold the upper edge of her torn rectum in Allis forceps, and invert its mucosa with a row of fine atraumatic catgut sutures (J). Continue them until you reach the mucocutaneous margin of her anal opening, so as to make her a normal anus.
Reinforce and bury the first layer of sutures with a second layer (K). This will reduce the the size of her rectum, but only temporarily.
Fish for the retracted ends of her sphincter ani muscles, which you will find buried in dimples at either side of her anus. Use hooks (L), or dip in with fairly fine artery forceps. Bring the hooks together to see if you have secured her sphincter (M and N). Bring the ends of her sphincter ani together with at least 3 1/0 catgut sutures.
Place several interrupted sutures in her levator muscles (O and P). When they are all in place, tie and cut them.
Excise any excess tissue on the flaps of her vagina (Q). Bring the raw edges of her vaginal wall together with interrupted catgut sutures (R, and S). Hold each one until the next is in position, and then cut it. When you have closed her vagina, close her perineal skin. The last two or three of these sutures should complete the formation of her anus, so that rugae radiate from it like the spokes of a wheel. If they don't, you have not done the operation as you should.
POSTOPERATIVELY, manage her as for an acute tear (18.15).
Fig. 18-18 SUSPICIOUS EVIDENCE. If a postpartum patient has a mass contiguous with the uterus (A), which does not disappear on catheterizing the bladder (B), but persists (C), it is probably a haematoma of her broad ligament due to rupture of her uterus. If a previous Caesarean section has left scar D, suspect strongly that it was classical. Scar E, might be either. F, is almost certainly a lower segment scar. After Nash and Drouin with the kind permission of the Editor of Tropical Doctor