Oxford Handbook of Midwifery (86 page)

There are three different types of forceps (Table 18.4).

Table 18.4
Types of delivery forceps

Wrigley’s Small size, for ‘lift out’ from lower cavity

Neville Barnes Straight, mid-cavity, at least pudendal block required Kielland’s Mid-cavity rotational forceps, epidural essential

Procedure

• The bladder is emptied
  
• Effectiveness of analgesia is assessed
  
• The appropriate forceps are applied between contractions
  
• Rotation of the fetal head is attempted if needed
  
• When the forceps are safely in place, traction is applied with contractions and the woman encouraged to push
  
• The obstetrician may perform an episiotomy as the fetal head distends the perineum
  
• The baby should be delivered within two or three contractions
  
• The forceps are removed when the head is delivered and the baby can be delivered on to the mother’s abdomen.
  

  Risks and complications
  

  The baby
  

CHAPTER 18
High-risk labour

374

• In a traumatic forceps delivery, cerebral irritability may occur due to cerebral oedema or haemorrhage. Cephalhaematoma may occasionally form as a result of trauma from forceps delivery (b see Examination of the newborn, p. 304).
  

  The mother
  

• The mother may experience vaginal tears caused by the forceps.
  

  •
  Perineal bruising, oedema, and occasionally haematoma may occur.
  

• Perineal trauma may be caused by extended episiotomy.
  
• Bruising and trauma to the urethra may cause retention or dysuria, haematuria, or incontinence.
  

  Ventouse delivery
  

  The application of a suction cup to the fetal scalp to facilitate delivery by traction is associated with less maternal trauma than forceps delivery.
  

  The indications for ventouse delivery are the same as for forceps. The obstetrician will need the same information before proceeding and the midwife will make similar preparations for delivery. Training is now available for specialist midwives to become ventouse practitioners.
  

  Selection of the ventouse extractor
  

• Electric pumps are efficient at maintaining the optimum vacuum pressure and are easy to operate, with a variety of cups available.
  
  • The usual size is 5cm silicon/rubber cup for a normal occipito- anterior presentation.
    
  • A posterior cup (which is metal and flatter in shape) is available for occipito-transverse or posterior positions.
    
• Hand-operated vacuum pumps may appear less anxiety provoking for the woman.
  
  • Examples are the Mityvac
    ^®
    , a cup for single use which can be attached to a handheld pump, and the Kiwi Omnicup, a small, totally disposable device.
    

    Procedure
    

• Explain the procedure carefully to the woman and partner, and obtain consent. Keep them informed of progress.
  
• The maternal position used for delivery is lithotomy, as for forceps.
  
• Perform a vaginal examination and determine the position of the fetal head.
  
• Select an appropriate cup and apply to the fetal head at the midline, just in front of the occiput. The obstetrician will ensure that no cervix or vaginal tissue is trapped under the cup before applying suction.
  
• The vacuum is built up gradually from 0.2kg/cm to 0.8kg/cm (0.2kg/cm at 2min intervals).
  
• Once the optimum pressure is achieved, with a strong uterine contraction and maternal expulsive pushing, steady traction is exerted gently on the fetal head following the line of the pelvic axis (curve of Carus). Descent should occur and, if necessary, rotation to an anterior position may be achieved.
  
• An episiotomy is not usually needed. The head is controlled carefully during crowning. As soon as the head is delivered the vacuum is released. The body is delivered as normal.
  

  MEASURES TO ASSIST BIRTH
  

  375
  

  Complications
  

A chignon develops, which is an area of bruising and oedema the approximate shape of the suction cup. This usually resolves without problem in a few days.

CHAPTER 18
High-risk labour

376‌‌

Caesarean section

Types of caesarean section

Classical caesarean section

• This is used only in an emergency or when there is obstruction (placenta/fibroids) in the lower segment.
  

  •
  It may be necessary to perform a caesarean section prematurely when
  

  the lower segment is not fully formed (before 32 weeks’ gestation).
  

• The incision is made longitudinally in the upper segment of the uterus.
  

  Since the upper segment has a thick muscular structure, there is a higher incidence of excessive blood loss and rupture of the scar subsequently.
  

  Lower-segment caesarean section
  

• This is the most common type of caesarean section.
  
• The lower segment is thinner and not so vascular, therefore blood loss can be less, with better healing, and lower infection rate. Cosmetically the ‘bikini line’ scar is more discrete and acceptable to women.
  

  Caesarean section and hysterectomy
  

  Very occasionally, in a severe emergency such as massive haemorrhage, uterine rupture, or an adherent placenta (placenta accreta) this might be necessary.
  

  Some indications for planned/elective caesarean section
  

• Singleton breech presentation when ECV was ineffective or contraindicated.
  
• Transverse lie or malpresentation (such as brow presentation).
  
• Placenta praevia.
  
• A twin pregnancy when the first twin is breech.
  
• Triplets.
  
• HIV and hepatitis C.
  
• Genital herpes is present during the third trimester of pregnancy.
  
• Maternal request, for example, where there has been a previous delivery that caused physical or psychological trauma.
  

  Plan of care
  

• Organize a consultant appointment to discuss the mode of delivery when the woman’s pregnancy has reached about 36 weeks’ gestation.
  
• The final decision should be made by a consultant obstetrician in conjunction with the parents.
  
• Give information clearly, in a way that can be understood by the parents.
  

  Difference of opinion
  

• If a consultant declines a request for a caesarean section, the woman can request a second opinion.
  
• A competent pregnant woman can refuse a caesarean section even if she puts herself and her baby at risk.
  ¹
  

  CAESAREAN SECTION
  

  377
  

  Arrangements for planned LSCS