Vaginal Delivery DK Dutta
INDEX
ABCDEFGHIKLMNOPRSTUV
A
Abnormal foetal heart rate 86
Active management of the third stage 38
controlled cord traction 38
immediate oxytocin 38
uterine massage 38
Anaesthesia for vaginal delivery 89
Anatomical changes in passage 15
Anatomy of female pelvis 1
Artificial rupture of membranes 44
Augmentation of labour 44
B
Bimanual compression of the uterus 117
Breech delivery 77
arms are stretched above the head or folded around the neck 79
baby’s body cannot be turned 80
delivery of the arms 78
delivery of the buttocks and legs 78
delivery of the head 80
entrapped (stuck) head 81
C
Complication during delivery 136
foetal 137
morbidity 137
mortality 137
maternal 136
morbidity 136
mortality 136
Complications of instrumental vaginal delivery 100
foetal complications 100
maternal complications 100
Concept of optimising labour 41
Contraction of uterus 14
Counselling and litigation during vaginal delivery 136
Counselling of mother 136
Craniotomy and craniocentesis 128
aftercoming head during breech delivery 131
breech presentation with entrapped head 130
cephalic presentation 128
closed cervix 130
craniocentesis (skull puncture) 130
craniotomy (skull perforation) 128
during caesarean section 131
fully dilated cervix 130
indication 128
D
Delayed (secondary) postpartum haemorrhage 120
Descent 26
Destructive operation 128
Diagnosis of malpositions 60
symptoms and signs 60
breech presentation 62
brow presentation 61
compound presentation 62
face presentation 61
occiput posterior position 60
occiput transverse position 61
transverse lie and shoulder presentation 63
Diagnosis of normal labour 24
assessment of engagement and descent of the foetus 24
diagnosis and confirmation of labour 24
diagnosis of stage and phase of labour 24
identification of presentation and position of the foetus 24
Diagnosis of vaginal bleeding after childbirth 114
Diameters of pelvic brim 4
anteroposterior diameter 4
oblique diameter 5
transverse 5
E
Effacement and dilatation in 17
multigravida 17
primigravida 17
Episiotomy 104
Examination of tears 40
F
Foetal distress in labour 86
Foley catheter 50
G
Guideline during delivery 138
H
How to prevent litigation 137
I
Induction of labour 44
Infiltration of perineal tissue with local anaesthetic 104
Inverted uterus 119
K
Ketamine 93
Ketamine infusion 94
induction and maintenance 94
premedication 94
L
Labour activity of uterine muscle fibre 14
Labour with a scarred uterus 84
general management 84
rupture of uterine scars 84
specific management 84
trial of labour 85
Labour with breech delivery 77
Landmarks of the foetal skull 28
Litigation of vaginal delivery 137
M
Malposition and malpresentation of labour 57
Management of malposition 63
breech presentation 67
brow presentation 64
chin-anterior position 66
chin-posterior position 66
compound presentation 66
early labour 67
face presentation 65
occiput posterior positions 63
vaginal breech delivery 68
Management of overdistended uterus 73
excess amniotic fluid 73
multiple pregnancy 73
breech presentation 75
first baby 73
second or additional baby(s) 74
transverse lie 75
vertex presentation 74
single large foetus 73
Management of unsatisfactory progress of labour 53
cephalopelvic disproportion 54
false labour 53
inadequate uterine activity 55
obstruction 55
prolonged active phase 54
prolonged expulsive phase 56
prolonged latent phase 53
Manual removal of placenta 108
Maternal bony pelvis 1
false pelvis 1
true pelvis 2
Mechanism of oplacental separation 22
Methods of separation 22
Mathews Duncan method 23
Schultze method 22
Midpelvis 8
Misoprostol 50
Modified WHO partograph 33
Moulding 31
sutures apposed 31
sutures overlapped and not reducible 31
sutures overlapped but reducible 31
N
Normal childbirth 36
Normal labour and childbirth 24
O
Occiput anterior positions 29
Occiput transverse position 28
Overdistended uterus 72
P
Paracervical block 89
Passenger (foetus) 18
Pelvic axis 10
Pelvic cavity 6
Pelvic outlet 6
Pelvis inlet or brim 3
Perineal approach 91
Physiology of power in labour 12
primary forces 12
secondary forces 12
Physiology of primary force in labour 12
Presentation and position 27
Procedure of symphysiotomy 133
Progress of first stage of labour 35
Progress of foetal condition 35
Progress of maternal condition 36
Progress of second stage of labour 35
Prolapsed cord 87
Pudendal block 90
R
Repair of cervical tears 121
Repair of episiotomy 106
muscle layer 106
skin 106
vaginal mucosa 106
Repair of first and second degree tears 122
Repair of third and fourth degree perineal tears 124
Repair of vaginal and perineal tears 122
Repair the tear in the operating room 125
Retained placenta 118
Retained placental fragments 118
S
Sample partograph for normal labour 34
Shape of brim 11
android 11
anthropoid 11
gynaecoid 11
platypelloid 11
Specific management of prolapsed cord 88
cord not pulsating 88
pulsating cord 88
Symphysiotomy 132
T
Tears of cervix, vagina or perineum 118
U
Unsatisfactory progress of labour 52
Use of oxytocic drugs 116
Using the partograph 30
V
Vacuum extraction 96
Vacuum extraction andm symphysiotomy 99
Vaginal approach 92
Vaginal bleeding after childbirth 112
diagnosis 114
general management 113
Vaginal examination 27, 30
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Chapter Notes

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Anatomy of Female Pelvis1

Debidas Dutta,
DK Dutta,
Indranil Dutta
Maternal true pelvis is a made of 4 bones — (a) Two innominate or hip bones one either side, (b) Sacrum, (c) Coccyx on the back in the middle.
Maternal bony pelvis is divided by pelvic brim.
  1. False pelvis (above)
    False pelvis made up by lumbar vertebrae posteriorly, iliac fossae laterally and anterior abdominal wall anteriorly.
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    Fig. 1.1: Hip bone with secondary ossilic centres
    2
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    Fig. 1.2: Measuring interspinous diameter with pelvimeter
  2. True pelvis (below)
    1. Interspinous-transverse distance between outer borders of anterior superior iliac spines (9-10″–22-25 cm).
    2. Intercristal-maximum transverse distance between outer lips of iliac crests (10-11″–25-28 cm).
    3. External conjugate (Baudelocque's diameter) Anteroposterior distance between tip of last lumbar vertebra and midpoint of superior border of symphysis pubis. It measures 71/2″ (19 cm).
True Pelvis: This forms the bony birth passage for foetus. True pelvis is a curved cylinder.
Anteriorly canal is short formed by posterior surface of symphysis pubis (4 cm in depth).
Posteriorly curved sacrum (straight line depth 10 cm, curved depth 12 cm).3
Laterally, side walls run straight parallel. It is formed by pubic ramus, obturator foramen, ischium, scrosciatic notch and part of ilium. Obturator foramen is covered by obturator internus muscle.
Pelvic outlet is bounded by arcuate ligament at subpubic arch anteriorly, the medial margins of ischial tuberosities, the sacrotuberous ligaments laterally and by the sacrum and coccyx posteriorly.
True pelvis is described under:
  1. Pelvic inlet or brim
  2. Pelvic cavity
  3. Pelvic outlet
  4. Midpelvis.
 
 
Pelvic Inlet or Brim
Pelvic brim or Inlet or upper pelvic strait is bounded on each side by upper border of symphysis pubic crest, iliopectineal line, sacroiliac joint, ala of the sacrum and sacral promontory from before backward.
Plane of pelvic brim is the space of pelvic brim through which imaginary plane is drawn.
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Fig. 1.3: Plane of pelvic brim
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Fig. 1.4: Pelvic inclination
Shape of plane of pelvic brim. It is rounded with slight anteroposterior flattening due to forward projection of sacral promontory.
Pelvic inclination: In erect posture of woman, plane of pelvic brim lies at angle of 55° with horizontal and 135° with vertical line of spine. In this pelvic inclination, foetal head engages into the pelvic cavity.
Diameters of pelvic brim: Four diameters—anteroposterior, two obliques and transverse.
  1. Anteroposterior diameter (true conjugate, conjugate vera) 4¼″ (10.6 cm, 11 cm Rounded up) extends from midpoint of sacral promontory to midpoint of upper border of symphysis pubis. Obstetric conjugate (4″—10 cm) is measured from centre of sacral promontory behind to the nearest point in the midline on the posterior surface of the symphysis pubis in front. This pointlies ¼″ (6 mm) below superior border of symphysis pubis. It is the shortest diameter of pelvic brim. Clinically obstetric conjugate cannot be measured. It is indirectly measured by deducting ½″ (1.25 cm) from measurement of diagonal conjugate. The latter is taken in clinical practice.5
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    Fig. 1.5: Planes of true pelvis
  2. Oblique diameter (4¾″—12 cm) measures from one sacroiliac joint to opposite iliopectineal eminence. Right oblique is taken from right sacroiliac joint to left iliopectineal eminence. Left oblique is taken from left sacroiliac joint to right iliopectineal eminence.
  3. Transverse-5¼″ (13 cm) is the maximum distance between furthest apart points on the iliopectineal lines-midpoints between iliopectineal eminence and sacroiliac joint. This diameter lies cloesr to sacral promontory (at a distance of 4 cm) than symphysis pubis.
In living, available transverse diameter is about 1.25 cm (½″) less than anatomical transverse due to overlapping of psoas muscles. This diameter bisects the anteroposterior diameter of brim. Sacrocotyloid diameter (3¾ — 9.4 cm) is the distance between midpoint of sacral promontory and iliopectineal eminence. In flat pelvis, biparietal diameter of foetal head negotiates through this diameter.
Pelvic of brim index: This is relation between the anteroposterior and transverse diameters of pelvis brim.
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Average pelvic index is 85-90. A reduced pelvic index means relative flatness of anteroposterior diameter.
 
Pelvic Cavity
Boundary: It is bounded above by plane of pelvic brim and below by plane passing through ischial spines—least pelvic dimension (midpelvis).
Plane: Plane of greatest pelvic dimension is the space in the middle of pelvic cavity. It is bounded anteriorly by midpoint of posterior surface of symphysis pubis, laterally ischial bone over middle of acetabulum and posteriorly to junction of second and third sacral vertebrae. It is the most roomy plane in true pelvis.
Shape of plane: Round
Diameters.
  • Anteroposterior—4¾″ (12 cm)
  • Oblique—4¾″ (12 cm)
  • Transverse—4¾″ (12 cm)
 
Pelvic Outlet
Pelvic outlet is bounded by inferior border of symphysis pubis, pubic bone, laterallyischium, sacrotuberous and sacrospinous ligaments and posteriorly tip of coccyx.
Planes of pelvic outlet They lie on two triangular planes with base joining two ischial tuberosities due to downward projection of the ischial tuberosities.
Shape of the outlet planes—Anteroposterior Oval.
 
Diameters
  1. Anteroposterior-5¼″ (13 cm) extends from midpoint of inferior border of symphysis pubis to tip of coccyx. Posterior point becomes tip of sacrum when coccyx is displaced backward during delivery of foetal head. Oblique 4¾″ (12 cm).
    7
  2. Transverse-4¼″ (10.6 cm) measuring from medial border of the ischial tuberosities. This is called Transverse Diameter of Outlet (TDO) and can be clinically measured.
Obstetric outlet or lower pelvic strait is the lower least roomy bony segment of true pelvis bounded above by plane passing through ischial spines (plane of least pelvic dimension) and below by two planes of anatomical pelvic outlet. Its anterior wall is empty pubic arch, lateral walls by ischium and posterior wall by coccyx. In some pelves foetal head gets arrested at obstetric outlet.
Diagonal conjugate measures between lower margin of the symphysis pubis and centre of sacral promontory. This is clinically measured. It measures 4¾″ (12 cm) in normal sized pelvis.
Posterior sagittal diameters are the posterior segments of anteroposterior diameters of true pelvis lying behind maximum transverse diameters.
Posterior sagittal diameter of outlet is the anteroposterior distance between midpoint of TDO and tip of sacrum. It measures 3½″ (8.5 cm). It is clinically measured by pelvimeter between sacrococcygeal joint and anterior margin of anus.
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Fig. 1.6: Pelvic outlet
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Fig. 1.7: Pelvic outlet
Subpubic angle: It is formed by descending rami of pubic bones. It measures 90 degree or more.
Waste space of Morris at pubic arch. Normally subpubic arch is wide and round disc of 9.4 cm diameter. Diameter of wellflexed vertex can pass through pubic arch at a distance of 1 cm from midpoint of inferior border of symphysis pubis. This distance is called waste space of Morris. If the waste space of Morris is more than 1 cm due to marrow subpubic angle, available anteroposterior diameter of outlet becomes less and foetal head has to pass injuring perineum or even gets arrested.
 
Midpelvis
Midpelvis is the narrowest segment of true pelvis lying between obstetric outlet below and roomy pelvic cavity above.
Plane: Plane at midpelvis is called plane of least pelvic dimension.
Boundaries: Anteriorly lower border of symphysis pubis, inner aspect of inferior pubic ramus and obturator foramen, ischial spine, sacrospinous ligament and tip of sacrum. Ischial spines from two important lateral landmarks of this plane.9
Shape of plane—Anteroposterior Oval
 
Diameters
  • Anteroposterior—5¼″ (13 cm)
  • Oblique—4¾″ (12 cm)
  • Transverse—4″ (10 cm). This is the transverse distance between two ischial spines. This is called interspinous diameter.
It is the narrowest diameter of true pelvis. Posterior sagittal diameter of plane of least dimension is 4.5 cm or above lying between tip of sacrum and interspinous diameter.
Importance of ischial spine: Ischial spine on each side is an important bony landmark at ischium at midpelvis—the junction of pelvic cavity and obstetric outlet.
  1. Ischial spines from the origin of levator ani diaphragm.
  2. Descent of foetal head in the pelvis is clinically judged in relation to ischial spines.
  3. Foetal head rotates anterior from this level.
  4. Foetal head gets arrested at this level since plane of least dimension lies at it.
  5. Landmark used for pudendal block analgesia.
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    Fig. 1.8: Pelvic outlet
    10
    zoom view
    Fig. 1.9: Pelvic outlet
  6. Radiologically it can be viewed in superior-inferior view of pelvic brim.
 
PELVIC AXIS
Anatomical (curve of Carus): Anatomically pelvic axis is uniformly curved fitting with concavity of sacrum and joins the axes of pelvic inlet, cavity and outlet.
Obstetrical: Through this axis foetus passes through pelvis. Its direction is straight downward and backwards upto level of ischial spines and then directed forward.
 
 
Physiological Enlargement of True Pelvis
Radiological views show increase in width of symphysis pubis and sacroiliac joint during pregnancy. In labour space in pelvis increases significantly by backward rotation of sacrum, posterior displacement of coccyx.
Pelvic size and shapes: Pelvic size giving space in true pelvis is most important for delivery of foetus. Pelvic shape comes next important.11
Four types of pelvic shape (Caldwell and Moloy, 1933). Shape of true pelvis shows changes at all levels.
Here only shape of brim is given.
  1. Gynaecoid with round brim.
  2. Anthropoid with anteroposterior oval brim.
  3. Android with heartshaped brim.
  4. Platypelloid (simple flat) with kidney shaped transversely oval brim.
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Fig. 1.10: Four types of pelvic brim