Transcript MVA in Pregnancy – A Case Presentation

Vacuum-assisted Vaginal
Delivery
Max Brinsmead MB BS PhD
May 2015
History

Simpson 1794
 Malmstrom 1954
 Bird 1960’s
 O’Neill 1980’s
 Vacco 1990’s
Indications
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Maternal
– Exhaustion
– Hypertension
– CPD (with symphysiotomy)

Fetal
– Second stage delay
– Bradycardia
Requirements
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A trained operator
 Tested equipment
 Gestation >36w
 Cephalic presentation
 Dilatation 10 cm (unless skilled)
 Descent beyond spines (unless skilled)
 You must identify the occiput
 Contracting uterus
 Co operative mother
 Anaesthesia
 Empty bladder
 Episiotomy
Controversial
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Gestation 34 – 35 completed weeks
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Fetal bleeding disorder

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For example thrombocytopenia
Maternal blood borne viral infections
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It is generally agreed that Ventouse should not be
used at <34 weeks
Forceps are acceptable
For example HIV
Acceptable if fetal trauma is avoided
Incomplete cervical dilatation
 High second twin
Who should go to theatre for a trial?

Any head is palpable above the brim or the
head is station < 2 cm from spines
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Unless there is clearly no CPD and the indication is
suspected fetal compromise
Weigh up risk associated with delay vs risk
associated with failure
Fetal head rotation is >45 degrees from
occipito anterior
 Estimated fetal weight >4000 g
 Maternal BMI >30
Risks

Fetal
–
–
–
–
–
–
–
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Scalp bruising
Jaundice
Scalp laceration
Cephalhaematoma
Retinal haemorrhage
Subgaleal haemorrhage
Intracranial haemorrhage
Maternal
– Damage to vagina, bladder or bowel
Meta Analysis of RCT Ventouse
Vs Forceps

Ventouse is associated with a greater rate of
failure (about15%)

BUT

Overall Caesarean rate with Ventouse was
significantly lower
Meta Analysis of RCT Ventouse
Vs Forceps

Ventouse is associated with:
– Less maternal trauma (RR 0.41, CI 0.33 – 0.50)
– More vaginal deliveries (RR 1.69 CI 1.31 – 2.19)
– Less sphincteric dysfunction
– Less need for major analgesia
– Less perineal pain at 24 hours

But
– More cephalhaematomas (RR 2.38, CI 1.68 – 3.37)
– More retinal haemorrhages (RR 1.99, CI 1.35 – 2.96)
– More maternal concern about baby
– And forceps may be quicker
Meta Analysis of RCT Ventouse
Vs Forceps

Ventouse may be associated with
– Lower 5 minute Apgar score
 If used over a long period of time
– More scalp trauma
 If the cup detaches
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AND
Subgaleal & Intracranial haemorrhages

But these are rare
Meta Analysis of RCT Ventouse
Vs Forceps

Forceps may be associated with:
– Facial trauma
– Facial or other Cranial Nerve palsies


AND
Spinal cord injury with rotation

But this is rare
Meta Analysis of RCT Ventouse
Vs Forceps

Ventouse is associated with:
– More neonatal jaundice

But
– The need for phototherapy is the same as for
forceps
12 Year Follow Up of Patients delivered SVD,
Forceps & Ventouse or CS

Forceps was associated with:
– Increased risk of fecal incontinence
– 17% cf 11% for Ventouse
– (and 11% for SVD or CS)

But
– Slightly lower risk of urinary incontinence
– 54% cf 56% after Ventouse
– (and 55% for SVD, 40% for exclusive CS)
Tips for Safe & Successful Use

Wait for chignon formation
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PULL ONLY WITH CONTRACTIONS
Use a finger from the 2nd hand to prevent edge lifting of
the cup
Pull at right angles to the cup
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And this will follow the curve of Carus
The skill is akin to cord traction
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Not required for soft cups
A study of rapid vs slow suction found no difference in success
Knowing how firmly to pull short of detachment
Progress with every pull OR STOP
 Deliver within 20 minutes OR STOP
 Judicious use of episiotomy
 Sequential use of forceps only for “lift out”
 Collect paired cord blood for pH and gases
 Document carefully
After Care of the Woman

Rectal NSAID and regular oral thereafter plus Paracetamol
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Consider the need for:
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Document the time and volume of the first void
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Check residual volume if any doubt about complete emptying
Physiotherapy for the pelvic floor

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Thromboprophylaxis
Antibiotics (not routine)
Faecal softening agents
Preferably conducted by physiotherapist with expertise
Debriefing by the accoucheur

The evidence for special interventions to avoid depression does
not support the practice
A RCT of Kiwi Omnicup vs Conventional
Ventouse BJOG 2006
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206 women at Queen Charlotte and Chelsea hospitals
London randomised
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44% detachment rate with Kiwi cup vs 18% with
conventional ventouse
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Overall failure therefore was more common (RR 1.58,
CI 1.10 – 2.24
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Rate of maternal injury the same
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No serious neonatal trauma
Avoiding the need for assisted delivery
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Provide continuous one-to-one support for women in
labour

Encourage the upright position
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Avoid epidural anaesthesia if possible
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Delayed pushing if an epidural is used
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Judicious use of oxytocin in the second stage

Scalp sampling for lactate for non reassuring
cardiotocography
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