Assisted vaginal delivery : forceps and vacuum

1. THE COPPERBELT UNIVERSITY
SOM
4 & 6TH YEAR 2022
ASSITEDVAGINAL DELIVERY
PRESENTER: DR. KABELENGA
REGISTRAR OBGYN - NTH
08/11/2022
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2. Learning outcomes
 Define assisted vaginal deliveries (AVD)
 Classify AVD
 State the differences between ventouse and
forceps
 Indications
 Explain the Preliquisties for AVD
 Complications
 Care of a woman who undergoes AVD
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3. Def: Assisted vaginal delivery – Is vaginal delivery of a baby
perfomed with the help of vacuum (Ventouse) or a forceps
device (ACOG, 2020).
 Assisted vaginal delivery is also referred to as
instrumental or operative vaginal birth.
 Both instruments are safe and reliable methods of
assisting childbirth.
 Appropriate attention should be paid to the indications
and contraindications for the procedures.
 The operator should understand the benefits and
risks to both maternal and fetal of using either
instrument.
 The choice of instrument should suite both the
clinical circumstances and the preference of the
operator.
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4. Classification
1.Vacuum (Ventouse)
2. Forceps
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5. Vacuum (Ventouse)
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6. Definition of ventouse
 Vacuum extractor is a traction instrument
used to assist the maternal expulsive efforts
in extracting the foetus from the birth canal.
 It is designed to produce traction upon the
fetal scalp.
 It is not a device by which to apply rotation
forces.
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7. Vacuum extractorTypes
 Type of cup
◦ Metal
◦ Soft cup (Silastic cup)
 Type of Pump
◦ Hand
◦ Foot
◦ Electric
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9.  Vacuum extractor consists of round
metal or silica cups, with an attached
chain and a traction handle.
 The cups which fit onto the head of the
foetus come in various sizes: 30, 40, 50, and
60mm.
 Vacuum is created inside the cup using an
electric or manual/hand/foot pump.
 the vacuum is built up to a negative
pressure of 0.8kg/cm sq.
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10. Indications
Maternal
 Second stage dystocia
 Maternal conditions in which shortened
second stage or minimal expulsive effort is
beneficial.
 Cardiac disease
 Pulmonary compromise
 Retinal detachment
 Exhaustion
 Prolonged second stage labor
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11. Fetal
 Suspected fetal compromise requiring
immediate delivery e.g.
 Fetal distress in second stage
 Cord prolapse
 Abruptio placenta noted in second stage
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12. Preliquisties forVacuum delivery
 Before attempting a vacuum extraction certain
criteria must be met:-
 Vertex presentation,
 Term foetus,
 EFW>2500g
 Vertex engaged
 Exact position of the head determined
 Cervix at least 8 cm dilated
 Membranes ruptured
 Adequate maternal pelvis by clinical
assessment
 Maternal bladder empty
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13. Contraindications
Absolute
1. Non vertex, face or brow presentation
2. Prematurity or EFW<2500g
3. Unengaged vertex
4. Incompletely dilated cervix lessthan 8 cm
5. Clinical evidence of CPD
Relative
1. Mid-pelvic station
2. Unfavourable attitude
3. HIV positive mother!!!
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14. Technique 1
 The proper function of the vacuum
equipment should be ascertained before the
cup is applied.
 An appropriately sized cup is selected and
applied.
 Ensure urinary bladder is empty
 The cup is placed against the fetal head just
anterior to or over the posterior fontanelle.
 Great care is taken to ensure that no
maternal tissue is trapped between the fetal
head and the vacuum cup.
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15. Technique – 2
The vacuum is then created up to a negative
pressure of 0.8kg/cm sq.The operator waits
1 – 2 minutes for a chignon (artificial caput)
to form.
Steady, gentle traction is then exerted.The
traction should be intermittent and
coordinated with uterine contractions and
maternal expulsive efforts.
Traction should always be in the direction of
the birth canal – initially downward and
finally upward.
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16. Technique – 3
 With descent of the head, rotation to an OA
position may be effected if necessary.
 An episiotomy is optional
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17.  Ventouse cup should be placed on the
flexion or pivot point
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18. Insertion of
the suction
cup.
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19. Traction is
applied
downward.
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20. Complications
Maternal
 Birth canal trauma – rare if cup applied carefully
e.g.
Vagina tears
Urethral injuries
Cervical injuries
Fetal
 Scalp lacerations and bruising
 Cephalohaematomas later jaundice
 Retinal haemorrhage
 Intracraneal haemorrhage
 Clavicular fracture/shoulder dystocia
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21. Vacuum failure
 The procedure is deemed to have failed when
there has been failure to accomplish
descent/delivery according to the rule of
threes.
 The procedure should be abandoned at this
point.
Rule of threes
 3 pulls, over 3 contractions, no progress
 3 pop-offs, without obvious cause
 30 minutes elapsed time, delivery not imminent
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22. How to avoid significant complications
 Confirm indications and conditions for use
 Ensure proper anatomical placement
 Avoid entrapment of maternal soft tissue
 Ensure correct angle of traction
 Avoid excessive force
 Coordinate traction to maternal effort
 Apply the rule of threes; stop procedure
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23. Forceps Delivery
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24. Function of forceps
 Use of obstetrical forceps has decreased
significantly and has primarily been replaced by
the increased use of caesarean section.
 Obstetrical forceps are used for the following
functions:
traction of the fetal head
rotation of the fetal head
flexion of the fetal head
extension of the fetal head
 When one or more of these functions are
attempted there is simultaneous action of
compression of the fetal head.
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25. Indications and prerequisites
 Indications and prerequisites for forceps
delivery are very similar to those for vacuum
delivery.
Operator must be skilled
Empty urinary bladder
Adequate anaesthesia
Maternal obesity (BMI ≥ 30)
Clinically big baby (wt ≥ 3 kg)
Occipitoposterior position
Mid-cavity delivery
When 1/5th fetal head palpable per abdomen.
Prematurity (≤ 34 weeks).
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26. Classification of forceps delivery
1. Outlet forceps
 fetal head has reached the pelvic floor
 fetal head is at or on the perineum
 the sagittal suture is in AP diameter
2. Low forceps
 leading part of the vertex is at station +2 or lower
3. Mid forceps
 head is engaged (station at 0 or lower)
 leading part of vertex is above station +2
NB: Forceps should never be applied through an
incompletely dilated cervix or with an unengaged
presenting part.
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27.  Forceps
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28. Wrigley’s (outlet)
Forceps
Short & light. Pelvic & cephalic
curves
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29. Anderson’s
(Simpson’s) Forceps
Long, heavy shanks & handle.
Pelvic & cephalic curves
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30.  Kielland’s forceps
 Its advantages over the widely used long-curved
forceps are:
It can be used with advantages in unrotated
vertex or face presentation
Facilitates grasping and correction of asynclitic
head because of its sliding lock
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31. Outlet Forceps
Delivery
Choosing the left blade
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32. Outlet Forceps
Delivery
Applying the left blade
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33. Outlet Forceps
Delivery
Applying the right blade
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34. Outlet Forceps
Delivery
Locking the blades
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35. Outlet Forceps
Delivery.
Gentle traction with an
episiotomy at crowning.
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36. Outlet Forceps
Delivery.
The correct cephalic application
(in the mento-vertical line).
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37.  How forceps are applied
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38. Advantages ofVentouse Over Forceps - 1
 It can be used in unrotated or malrotated head
(OP, OT position). It helps in autorotation
 „
„
It is not a space-occupying device like the
forceps blades.
 „
„
Traction force is less (10 kg) compared to
forceps of 20Kg in primi & 13Kg in Multi
 „
„
It is comfortable and has lower rates of
maternal trauma and genital tract lacerations
 „
„
Analgesia need is less. Pudendal block with
perineal infiltration is adequate but for forceps
regional or general anesthesia is often needed
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39. Advantages ofVentouse Over Forceps -2
 „
„
Reduced maternal pelvic floor injuries and is
advocated as the instrument of first
choice.
 „
„
Perineal injury (3rd and 4th degree tears)
are less compared to forceps
 „
„
Postpartum maternal discomfort (pain) are
less compared to forceps
 „
„
Easier to learn comparing to forceps
 „
„
Simplicity of use in delivery makes it
convenient to the operator (suitable for
trained midwives)
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40.  Advantages of Forceps OverVentouse
 In cases, where moderate traction is required,
forceps will be more effective compared to
ventouse
•
•
Forceps operation can quickly expedite the
delivery in case of fetal distress where ventouse
will be unsuitable as it takes longer time
•
•
It is safer at any gestational age baby (even < 36
weeks).
The fetal head remains inside the protective
cage
•
•
It can be employed in anterior face or in after-
coming head of breech presentation, where
ventouse is contraindicated
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41. Advantages of Forceps OverVentouse – 2
 Lesser neonatal scalp trauma, retinal hemorrhage,
jaundice or cephalhematoma compared to ventouse
 •
•
Higher rate of successful vaginal delivery as ventouse
has got higher failure rates than forceps
 •
•
Cup detachment (Pop-off) occurs when the vacuum is
not maintained in ventouse. No such problems once
forceps blades are correctly applied
 •
•
Number of types of forceps are available for outlet,
mid-cavity or rotational delivery.
 Traction force is more (about 20 kg for a primi and
about 13 kg in a multi)
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42. Care of a woman who undergoes AVD
 Educated about the risk of urinary retention so
that they are aware of the importance of
bladder emptying in the postpartum period
 Reassess women after AVD for venous
thromboembolism risk and the need for
thromboprophylaxis
 A single prophylactic dose of IV Amoxicillin and
clavulanic acid/Flagyl or Ceftriaxone should be
recommended following AVD as it significantly
reduces confirmed or suspected maternal
infection
 Post traumatic stress disorder counseling
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43. END
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