Caesarean Section

Caesarean Section.

Indications for caesarean section

1. Pelvic contraction and presence of dystocia

Cephalopelvic disproportion.

Foetal malposition/malpresentation.

Incoordinate uterine action.

Non-progress of labour. Arrest pattern on partogram.

Soft tissue dystocia, constriction ring, cervical dystocia or stenosis, vaginal stenosis, soft tissue mass obstructing the pelvis.

Congenital anomaly of the pelvis—Naegele's pelvis, Robert's pelvis.

Failed forceps and threatened uterine rupure.

2. Previous uterine surgery

Previous caesarean section.

Hysterotomy for MTP.

Myomectomy.

Metroplasty.

Cornual implantation of the fallopian tubes.

MTP perforation repaired or left to heal spontaneously.

3. Haemorrhage

Placenta praevia.

Concealed abruptio placenta with living baby or threatening DIG.

Vasa praevia.

Cancer cervix.

4. Maternal disorders

Severe hypertension, pre-eclampsia, eclampsia.

Renal disease.

Diabetes mellitus.

Coarctation of the aorta.

Maternal genital herpes.

Maternal HIV infection.

Malignant disease awaiting delivery to commence chemotherapy. 5. Maternal obstetric and health problems

Elderly maternal age.

Previous prolonged infertility.

Previous plastic repair of the vagina—A-P repair, prolapse repair, previous surgery for stress urinary incontinence, previous repair of VVF (vesicovaginal fistula).

Bad obstetric history.

Previous difficult vaginal delivery.

Congenital uterine anomaly with malpresentations.

Abdominal cerclage for incompetent cervical os.

Foetal distress.

Previous unexplained foetal death.

Cord prolapse.

Malpresentations–brow, mentoposterior, transverse lie.

Placental insufficiency and IUGR.

Foetal macrosomia.

Rh isoimmunization—selected cases.

Breech presentations.

Multiple pregnancy.

Antenatal diagnosis of conjoint twins.

Types of caesarean sections

Types: Three types have been described:

Classical upper segment operation.

Lower segment caesarean section.

Extraperitoneal caesarean section.

Preoperative preparation for caesarean section: The following precautions are advised:

Obtain informed consent for surgery.

Shave and prepare back, abdomen and private parts.

Administer 30 ml of 0.3% molar sodium citrate orally an hour before surgery to neutralize the acid present. This is preferred over the particulate magnesium trisilicate.

Injection metoclopramide to facilitate stomach emptying has much to recommend.

Infuse the patient with a litre of Ringer lactate prior to surgery assures against supine hypotension following spinal anaesthesia.

Blood to be kept grouped and cross-matched.

Injection atropine 0.6 mg IM half hour before surgery.

Indwelling catheter.

Perioperative antibiotic prophylaxis readied for use immediately after the birth of the baby and cord clamping.

Neonatologist in readiness to receive the baby.

Choice of anaesthesia

The choice often depends on the indication, general condition of the patient, comfort of the surgeon and anaesthesiologist. The common types of anaesthesia used:

Spinal intrathecal administration of 0.8 to 1.0 ml of 5% Xylocaine or 0.5% Marcaine.

Epidural—continuous/single shot. Both Xylocaine 5% or Marcaine 0.5% can be used.

General anaesthesia—induction of anaesthesia with intravenous thiopentone sodium and IV scoline, followed by endotracheal intubation and maintainence on nitrous oxide, oxygen and ether.

Exceptionally the operation may be undertaken under local anaesthesia. Precautions prior to administration of anaesthesia

Test for Xylocaine sensitivity.

Prior to spinal anaesthesia, administration of an infusion of about a litre of Ringer lactate solution helps to prevent sudden hypotension.

After spinal anaesthesia the practice of placing a wedge under the patient's right hip to give a 15° left lateral tilt until the baby has been delivered safeguards against supine hypotension.

A slight Trendelenburg position also helps to counter the effects of hypotension.

Administration of one ounce of 0.3% sodium citrate preoperatively helps to neutralize stomach acid contents, this safeguards against Mendelson's syndrome caused by aspiration of acid stomach contents.

Preoperative administration of injection metoclopramide in case of emergency caesarean sections helps to empty the stomach.

Operative procedure

1. The lower segment caesarean section:

Position is supine with the operation table given a 15° tilt to secure a mild left lateral tilt. A slight Trendelenburg position is given after the anaesthetic level has fixed.

Ensure that the IV infusion is running well.

Ensure placement of an indwelling catheter.

Repeat an abdominal preperation and drape the patient to ensure proper asepsis.

Selection of incision depends on the presence or absence of a previous scar, surgeon's choice and the indication for which the operation is being performed.

Generally, gynaecologists prefer to make the Pfannenstiel incision because it is cosmetically superior, causes less postoperative pain and discomfort, heals better and there is a lower risk of postoperative incisional hernia. The disadvantages are that it requires greater technical skill, takes more time and it is not easy to extend it for gaining greater access without cutting the rectus muscles. The midline incision is easy, permits quick entry into the abdomen, it is easier to extend the incision should the need arise. However, cosmetically, it is less acceptable and the risks of incisional hernia are greater. The paramedian incision was used to reduce the risk of future incisional hernia. It is not much used in present day practice.

The abdomen is opened in layers until the peritoneum is visualized.

The peritoneum is picked up at the upper part of the incision between two forceps, palpated to make sure that no other underlying structure has been accidentally picked up, a niche is made, and the incision extended downwards taking care of the urinary bladder at the lower angle of the incision.

The uterus is exposed. The uterovesical fold of peritoneum is picked up, incised and extended laterally, the bladder pushed off the lower uterine segment to expose the same. The surgeon decides to place a transverse incision on the lower segment such as to facilitate easy delivery of the foetus.

As soon as the baby's head has been delivered, the mouth should be cleared with suction catheter, the baby delivered, cord clamped and cut and the baby received in a dry sterile sheet. It is handed over to the neonatologist.

The anaesthetist administers an oxytocin injection to facilitate placental separation.

The perioperative dose of antibiotic is administered.

The placenta and membranes removed by gentle cord traction.

The uterine cavity cleaned.

Ensure that the cervical os is open to permit drainage of lochia.

The edges of the incised lower segment are held up with Green-Armytage clamps. The angles identified. Any extensions noted. It is a good practice to secure the two angles to begin with. The cut edges are approximated with a continuous Vicryl suture to ensure haemostasis. The peritoneal cavity cleansed of any clots, blood, amniotic fluid.

There is an increasing trend to leave the peritoneal incisions (uterovesical fold and the parietal peritoneum) unsutered.

The rectus sheath is approximated with continuous Vicryl.

Subcutaneous bleeders caught and cauterized or ligated.

The skin edges approximated. A sterile dressing given.

Check the drainage of urine.

A sterile pad given to receive the lochia.

Vital parameters documented.

Patient transferred to the room under supervision of the anaesthesiologist.

Loose uterovesical folds of peritoneum incised transversely, (b) transverse incision in lower uterine segment, (c) digital extension laterally of incision in lower segment, (d) manually elevating the head out of the incision, (e) progressive delivery of the fetal head, (f) expulsion of the placenta.

2. The classical caesarean section: This operation is performed rarely. Indications: It is performed for the following indications:

Previous classical incision.

Lower uterine segment inaccessible because of spinal/pelvic deformities.

Dense previous adhesions over the lower segment making access to the lower segment difficult.

Presence of fibroids occupying the lower uterine segment.

Cancer cervix—A Wertheim's operation/radiotherapy planned thereafter.

Rarely, when great speed is required to save the baby in a dead or dying mother.

Disdvantages: These are as follows:

Greater risk of rupture in future pregnancy and labour.

Adhesion formation.

Infection.

Complications: These may affect the mother or the baby:

1. Maternal complications: These are as follows:

Anaesthetic complications—severe hypotension, cardiac arrest, aspiration, etc.

Haemorrhage and shock.

Infection.

Extension of incision and haematoma formation.

Injury to bladder, ureter.

Injury to bowel.

Peritonitis, distension, paralytic ileus.

Pelvic abscess.

Pelvic thrombophlebitis.

Thromboembolism, metastatic abscesses.

Pulmonary embolism.

Wound sepsis, dehiscence, burst abdomen.

Fistula formation.

Later incisional hernia, scar endometriosis.

Death.

2. Foetal complications: These may be:

Iatrogenic prematurity.

Accidental injury to the baby—accidental niche during opening of lower segment.

Birth asphyxia.

Foetal exsanguinations—severe bleeding from placenta praevia delaying delivery of the baby.

Birth injuries during foetal extraction.

Indications for a caesarean hysterectomy

Caesarean hysterectomy is an operation in which removal of the uterus is carried out after delivery of the baby by caesarean section.

The indications when such a need arises are:

Uncontrollable atonic PPH.

Placenta accreta.

Multiple myomas rendering repair of uterus difficult.

Severely infected uterus.

Cancer cervix.

Rupture of the uterus.