Vacuum delivery is one of the most important art to learn in labour ward. Kiwi is a simplified vacuum device. Mastering the techniques these devices can achieve good outcomes.
1. Vacuum delivery
Indunil Piyadigama
54th Annual Scientific Congress
Sri Lanka College of Obstetricians and Gynaecologists
Labour Care and Ward Management – Pre-congress Workshop
25th November 2021
2. • The initial applications of vacuum in
deliveries began in the 18th century
• Developed in 1705 by Dr. James Yonge
• Was not popular until the 1950s
• Was popularised due to series of studies
published by a Swedish obstetrician called
Dr. Tage Malmström
• Older clinicians preferred forceps – Due to
medical conservatism and original
training, higher success rates, and a
presumption of improved speed and
control of the birth process
• Trends in usage is changing - seemingly
easy to use, requires less
anaesthesia/analgesia, has lower maternal
morbidity, and is commonly believed to be
safe
3. Common
features of a
vacuum
extractor
A vacuum cup
of varying
shape,
composition,
diameter, and
depth
A fixed internal
vacuum grid or
guard within
the vacuum cup
A combined
vacuum pump /
handle or a
vacuum port for
a vacuum hose
attachment
A handle for
traction
4. Different vacuum extraction instruments
Type of the cup -
Stainless steel,
Polyethylene or
silastic plastic
Location of the
handle
How the vacuum
is generated
5. Metal cup
• A mushroom-shaped metal cup varying from
40 to 60 mm in diameter
• A centrally attached chain connects the cup to
a detachable handle that is used to apply
traction
• A mechanical or electrical suction device is
attached to the metal cup via a peripherally
located vacuum port
• The advantages
• Higher success rate
• Easier cup placement in the
occipitoposterior (OP) position
• Disadvantages
• Difficult application
• Uncomfortable
• Associated with an increased risk of fetal
scalp injuries
6. Soft or flexible
vacuum cups
• A bell shaped cup
• Centrally connected vacuum pump
• This same vacuum port is used for suction
• Advantages
• Less fetal cosmetic injury (principally scalp
injury) than rigid cups
• This partially reflects the inability of soft
cups to generate the same degree of scalp
traction as is possible when rigid cups are
applied
• Disadvantages
• Have a higher incidence of failure than
either rigid vacuum cups (plastic or metal)
7. Advances in vacuum
devises
• Traditionally, the soft cups are bell or funnel
shaped.
• A newer variety, the mushroom-shaped
vacuum cup, or M-cup, combines the
advantages of soft and metal cups
• In some plastic extractor designs, the relatively
rigid tube connecting the handle to the cup
precludes accurate placement of the
instrument when the fetal head is markedly
deflexed or occiput posterior
• The pump was in cooperated into the devise
9. Indications
for vacuum
delivery
No indication is absolute
• Distress
Fetal
• Shorten or reduce the effects of 2nd stage of labour
• Ex – Class III, IV heart disease, hypertensive crisis,
myasthenia, proliferative retinopathy
• Previous CS
• Maternal exhaustion
Maternal
• Primi - > 3hrs, >4hrs with regional anaesthesia
• Multi - > 2hr, >3hrs with regional anaesthesia
Inadequate progress
12. Examination
• Head 1/5th or less palpable
Abdominal
• Vertex
• FD, Membranes ruptures
• Position of the head
• Caput/ moulding – 0, +1, +2 (can
separate), +3 (cannot separate)
• Adequacy of pelvis
Vaginal
13. Preparation
• Explanation of the procedure
• Informed consent
• Verbal
• In theatre written
• Empty the bladder
• Lithotomy position
• Edge of the table
• Continuous CTG monitoring
• Additional help
15. Setting
• Higher risk of failure should be considered a trial – Theatre should be ready for CS within 30
minutes
• Ex –
• BMI >30
• EFW > 4kg
• OP position
• Mid cavity delivery/ head is palpable 1/5th
• Delivering in theatre doubles the decision to delivery interval (from 20 minutes to 59 minutes)
• For fetal distress in LR delivery can be done in 15minutes and in theatre in 30 minutes
• Therefore, risk benefit should be assessed before transferring
16. Other problems to be expected
• Shoulder dystocia
• PPH
• Neonatal resuscitation
20. • Episiotomy - is not recommended as a routine measure during a VE
operation unless the soft tissue impedes the descent of the
presenting part
• Ideally, descent of the presenting part should begin with the initial
traction effort
• If the operator is uncertain that descent has occurred, a maximum of
2 additional tractions may be attempted
21. • The maximum duration of a vacuum
extraction is unknown
• A maximum of 2-3 pop offs, three
sets of pulls and/or a total application
time of 15-20 minutes have all been
recommended
22. When to
abandon
When no progressive descent
with moderate traction during
each contraction
Where delivery is not imminent
following 3 contractions of a
correctly applied instrument by
an experience operator
23. Sequential use of instruments
• Increased risk of trauma to the infant – ICH, seizures, facial nerve injury, low APGAR
• Increase risk of lacerations and PPH
• Changing the delivery instruments can constitute good management. These include those
in which technical problems, such as a malfunctioning hand pump, a misapplied vacuum
cup, or traction in the incorrect vector of force
• The least desirable cases are those in which traction without progress or multiple pop-offs
occur following a correct application of the vacuum extractor and appropriate traction
• Outlet or low cavity forceps following vacuum can be used to reduce the risk of CS
24. Following procedure
• Cord blood
• Simple analgesics
• Antibiotics
• Documentation – Contemporaneous
• Attention to bladder function
• Counselling before discharge
25. Comparison of vacuum vs forceps -
Disadvantages
More likely to fail
Slower
More cephalhematomas (10%)
More retinal haemorrhages (50%)
More maternal worries about the baby
26. Comparison of vacuum vs forceps -
Advantages
3 times less perineal trauma than forceps
Less risk of PPH
Less pain at 24 hours
Lesser chance of feacal incontinence within the first 24 hours
27. Comparison of vacuum vs forceps - No
difference
CS
Low Apgar
Need of phototherapy
Long term faecal incontinence
Infant outcomes at 5 years
28. Neonatal complications
• Reported incidence of fetal death or severe
fetal injury from vacuum extraction is low
• This range from 0.1-3 cases per 1,000
extraction procedures
• Birth trauma is the major complication of
operative vaginal delivery
• The most serious complication is intracranial
haemorrhage
• Other complications
• Hematoma
• Abrasion
• Laceration
• Nerve palsy
• Cephalohematoma
• Retinal haemorrhage
• Subgaleal haemorrhage
• Skull fracture
29.
30. • Cephalohematomas
• Common
• But clinically unimportant
• Subgaleal hemorrhages
• Relatively rare
• But potentially life-threatening
31. Subgaleal or subaponeurotic haemorrhage
• From rupture of the emissary vein
• Condition is potentially life threatening – Mortality 20%
• These bleeds happen occasionally after spontaneous delivery
• Incidence varies from 0-50 per 1,000 vacuum extractions
33. Summary
• Newer vacum devices are easy to use
• There are no absolute indications for a delivery. Each case must be
individually assessed
• Cooperation of the patient is important
• Systematic approach can reduce complications
• Flexion point and the direction of pull are important technical aspects
to master
• Any procedure can be associated with complications
