Instrumental delivery Flashcards

1
Q

Discuss instrumental delivery
-Incidence (2)
-Fetal indications (1)
-Maternal indications (5)
-Indications due to labour (1)
-Chance of subsequent vaginal birth (1)

A
  1. Incidence
    -10% of vaginal births are instrumental deliveries
    -30% of nullips (UK data)
  2. Fetal indications
    -Fetal distress in second stage
  3. Maternal
    -Cardiac disease with contra-indication to push
    -Hypertensive crisis
    -Proliferative retinopathy
    -Cerebral aneurysm
    -Maternal exhaustion
  4. Labour
    -Prolonged second stage
  5. Chance of subsequent vaginal birth - 78-91%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the contra-indications to instrumental delivery?
-All instrumentals (5)
-Ventouse delivery (4)

A
  1. All instrumentals
    -Risk of fetal bleeding - haemophilia or plt disorder
    -Risk of fetal skull fracture - osteogenesis imperfecta
    -Mother refusal
    -Not fully dilated
    -Fetal head above spines
  2. Ventouse delivery
    -Face presentation
    -<34 weeks. Caution from 34-36 weeks (Relative contra-indication)
    -Multiple FBS (relative contra-indication)
    -Maternal condition where valsalva is contraindicated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Discuss factors that reduce the need for instrumental delivery (6)

A

-One to one continuous care (RR 0.9)
-Upright or lateral position in second stage of labour (RR 0.75) unless has epidural and then left lateral is better.
-Avoidance of epidural (Old data and now epidurals are less dense)
-Appropriate use of oxytocin - in nulips with malposition or inadequate contractions or second stage in nulips with an epidural
-Passive decent for up to 2 hrs or until urge to push
-Manual rotation of malpresentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What factors increase the risk of failed instrumental delivery (6)

A

-BMI >30
-Macrosomia
-OP position
-Mid-cavity delivery
-Short maternal stature
-Head circumference >95%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Discuss the classifications of instrumental delivery
-Outlet (4)
-Low cavity (2)
-Mid cavity (3)
-High (3)

A
  1. Outlet
    Fetal scalp seen without separating the labia
    Fetal skull on pelvic floor
    Fetal head at perineum
    Position is direct OA or within 45 degrees L or R of these
  2. Low cavity
    Fetal skull is at +2 or more but not at level of pelvic floor
    Position is either <45 degrees from DOA or > 45 degrees from DOA
  3. Mid cavity
    Fetal Head is no more than 1/5th palpable above the brim
    Fetal skull is between +2 and spines
    Position is either <45 degrees from DOA or > 45 degrees from DOA
  4. High
    Fetal head is 2 or more 5ths above pelvic brim
    Fetal skull is above the ischial spines
    High instrumentals are not recommended
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the prerequisites for instrumental delivery (9)

A

-1/5th head abdominally or less
-Fully dilated
-At or below spines
-Vertex presentation
-Exact position known (Use USS)
-Adequate pelvis
-Ruptured membranes
-Consent from mother
-Caput and moulding <2+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Discuss choice of instrument for instrumental delivery
-What should be considered (7)
-When should forceps be chosen (6)
-When should ventouse be chosen (1)

A
  1. What should be considered
    -Position and station of baby
    -Amount of caput and moulding
    -Effectiveness of analgesia
    -Parity
    -Urgency
    -Maternal choice
    -Skill of operator
  2. When should forceps be used
    -Ineffective maternal effort
    -Valsalva is contra-indicated
    -If needed for the after coming head in breech
    -<34 weeks
    -Too much caput and moulding
    -Requirement of rapid delivery
  3. When should ventouse be used
    -Use in absence of clear indication for forceps delivery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Discuss the findings of forceps vs ventouse
-Outcomes more common with forceps (5)
-Outcomes less common with forceps (3)
-No difference between forceps or ventous (3)

A
  1. Outcomes more common with forceps
    -Achieve vaginal birth RR 0.65
    -3&4th degree tears RR 1.89
    -Perineal injury RR 2.48
    -Incontinence/ altered continence RR 1.77. No diff at 5yrs.
    -Facial injury RR 5.1
  2. Outcomes less likely with forceps
    -Failed instrumental RR 0.65
    -Cephalohaematoma RR 2.4
    -Retinal haemorrhage RR 2.0
  3. No difference
    -Any neonatal injury
    -Low apgar score at 5 mins
    -Fetal acidosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the maternal risks of instrumental delivery (8)

A
  1. Perineal trauma
  2. Anal sphincter trauma - ventouse 4% forceps 12%
  3. PPH
  4. Urinary difficulties
  5. Pelvic floor injury
  6. Prolapse
  7. Dyspareunia
  8. PTSD and psychological conditions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the fetal risks of instrumental delivery (9)

A
  1. Shoulder dystocia
  2. Brachial plexus injury
  3. Cervical spine injury 07:1000
  4. Skull fracture - rare
  5. Cranial bleeding
    -Cephalohaematoma - worse with ventouse but not NS
    -Subgaleal haemorrhage 1:300 ventouse deliveries
    -Intracranial haemorrhage 1:600 forceps 1:800 ventouse, 1:900 EMCS
  6. Facial nerve palsy and corneal abrasion (forceps)
  7. Minor scalp and soft tissue damage
  8. Retinal haemorrhage - ventouse
  9. NICU admission
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Discuss failed instrumental
-Considerations for next action
-Impact to mother if sequential use of instruments
-Impact to fetus if sequential use of instruments

A
  1. Consideration for next action
    -Review indication for instrumental
    -Options are switch instruments, maternal effort, CS
    -Individualise care with maternal input
  2. Impact to mother
    -Increased PPH
    -Increased blood transfusion
    -Increased lower segment tear
    -Increased bladder damage
    -Increased Hysterectomy
    -Increased ICU admission
  3. Impact to baby
    -Increased need for resus
    -Increased neonatal acidosis
    -Increased intracranial haemorrhage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Discuss postpartum care for women with instrumental delivery

A
  1. IV Augmentin with 3hrs (ANODE trial - 58% reduction in infection)
  2. Take cord gases
  3. Delayed cord clamping if safe
  4. Active third stage
  5. Examine and repair perineum
  6. Analgesia
  7. Debrief
  8. Perineal cares
  9. Bladder cares - IDC for 12hrs if epidural/spinal
  10. Laxatives
  11. Physiotherapy
  12. Consider thromboprophylaxis
    -Instrumental unless mid cavity is not itself a risk factor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Discuss types of ventouse cup and uses
-Silicone cup (3)
-Metal cup (3)
-Kiwi cup (2)

A
  1. Silicone cup
    -Handle on tubing
    -Easy to insert
    -Use for uncomplicated deliveries with <45 degrees rotation
  2. Metal cup
    -OA or OP cups types. Use OP cup if deflexed OT position
    -Use for difficult delivery, oblique, mid cavity, moderate amount of caput, large fetus or deflexed head
    -More likely to result in successful VB (OR 1.6)
  3. Kiwi cup
    -Use for any delivery
    -Less successful but similar safety profile
    -Less scalp injuries (13% cf 24%)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Discuss placement of ventouse cup and delivery steps (10)

A
  1. Place cup so force is directly through flexion point and evenly across sagital suture.
  2. Flexion point is 3cm from posterior fontanell and 6 cm from anterior fontanelle
  3. Place rim of cup at edge of posterior fontanelle
  4. Apply 20g/cm of pressure and check for suction and whether maternal tissue is caught
  5. Increase pressure to 80g/cm
  6. Provide traction at right angles of cup with contractions with contractions and maternal effort. Keep thumb on cup and finger on vertex
  7. Between pulls maintain gentle traction to avoid loss of station
  8. Avoid rocking or twisting of the cup - increases subgaleal haemorrhage
  9. As head descends past symphysis pubis start to apply traction from horizontal to vertical
  10. Consider episiotomy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the reasons ventouse delivery should be abandoned

A
  1. Time
    Upper limit until delivery is 20mins from first pull
    Consider different approach if birth not looking imminent by 15mins
  2. Number of pulls
    3 pulls at a maximum with no decent
    If decent can do more pulls if at pelvic floor
  3. Cup detachments
    -Up to 3 pop offs if decent
    -Rapid decompression leads to vessel damage and increases risk of sub-galeal haemorrhage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Discuss the types of forceps
-Straight forceps (3)
-Rotational forceps (1)
-Short forceps (2)

A
  1. Straight forceps
    -Neville Barnes
    -Andersons
    -Simpsons
  2. Rotational forceps
    -Keillands
  3. Short
    -Pipers
    -Wrigleys
17
Q

What are the checks that should be done to make sure the forceps are placed correctly (4)

A
  1. Posterior fontanelle should be midway between the shanks and 1cm above the plane of the shanks. If > 1cm then can cause head extension and difficult delivery
  2. Fenestrations should be barely palpable - only a finger tip. If palpable the blades are not cupping the fetal face but digging into the cheeks
  3. Lamboid sutures should be above the eqi-distant from the superior surface of the blades
  4. Apply the blades the same way for DOA and DOP
18
Q

Discuss manual rotation
-Success rate (3)

A
  1. Success rate
    -Up to 89%
    -Reduces rate of CS
    -Low chance of success if nulliparous, performed before full dilitation or first stage complicated by FTP
19
Q

Discuss manual rotation - techniques (2)

A

Two type of technique
1. First technique
-Place whole hand in vagina with palm up
-Flex and slightly dislogde head
-Supernate or pronate hand in between contractions
-Hold fetal head in place for few contractions or until instrument applied to maintain position
2. Second technique
-Place fingers on lamboid sutures and use dialing motion to rotate fetal head
-Hold fetal head for few contractions or until instrument applied to maintain position

20
Q

Discuss rotational forceps
-Type of forceps used
-Risk compared to CS (4)
-Risks compared to rotational ventouse (2)

A
  1. Type of forceps - Keillands
  2. Risk compared to CS
    -Increased traumatic intracranial injury
    -Increased cervical spine injury
    -No evidence of increased maternal morbidity
    -No evidence of long term morbidity for baby
  3. Risk compared to rotational ventouse
    -Less failure
    -Less intracranial and supaponeuritic/ Subgaleal haemorrhage
21
Q

When is rotational delivery considered

A

When occiput is more than 45 degrees from OA and in mid cavity

22
Q

Discuss considerations for rotational forceps delivery

A
  1. The fetal head must be engaged (by abdo and vaginal assessment
  2. Analgesia should be adequate - epidural or spinal
  3. Only do if experienced or under supervision
  4. Rotate with a relaxed uterus. Consider tocolysis - GTN
  5. Do not rotate and apply traction at the same time. Rotate first traction second
  6. Abandon the procedure if:
    -Application is difficult
    -Handles don’t easily approximate
    -Rotation is not easily achieved
    -Lack of decent with moderate pressure
23
Q

Discuss the key factors in rotational forceps (11 steps) (RANZCOG)

A
  1. Aim to prevent fetal malposition
    -Judicious use of oxytocin
    -Manual rotation
  2. Assess to determine if suitable
    -Check analgesia
    -If position difficult to assess = red flag
    -Empty woman’s bladder
  3. Communicate with woman and gain consent
    -Maternal complications - cervical and perineal trauma
    -Fetal complications - cervical spine and ICH
    -Episiotomy recommended
  4. Prepare staff and birthing room
  5. Reconfirm fetal position
  6. Apply forceps
    -Use wandering technique
    -Apply between contractions
    -Correct asyniclitism between contractions
    -If difficult = Red flag
  7. Rotate
    -Between contractions
    -Use force with one hand. Other hand on maternal abdo
    -Ensure OA position after rotation
    -Red flag difficult rotation
  8. Apply traction
    -Traction during a contraction
    -Cut Episiotomy
    -Too much force required = Red flag
  9. Birth of head
    -Remove blades
    -Prepare for shoulder dystocia
  10. Check and repair perineum
  11. Debrief and document
24
Q

Discuss episiotomy use with instrumental delivery
-Reduction in OASIS tears with forceps
-Reduction in OASIS tears with ventouse
-NNT to avoid OASIS tears overall
-Recommendations

A
  1. Reduction for forceps - 24%
  2. Reduction for ventouse - 16%
  3. NNT 19 to avoid 1 OASIS injury
  4. Recommendations
    -Consider for all women having their first vaginal birth requiring instruments
25
Q

Discuss the ANODE trial
-Aim
-Method
-Outcomes

A
  1. To see if a stat dose of augmentin prevented maternal infection for operative VB
  2. Method
    -Multi center RCT blinded
  3. Outcomes
    -Confirmed or suspected infection within 6 weeks of birth
26
Q

Discuss the ANODE trial
-Numbers included
-Findings

A
  1. Numbers included
    -3500
  2. Results
    -Suspected or confirmed infection 11% in Augmentin group 19% in placebo (SS)
    -Less perineal pain and breakdown in augmentin group (SS)