Anatomy Flashcards
names of fetal skull points
- suboccipito bramati
- suboccipito frontal
- occipitp-frontal
- mento-vertical
- submento-bregmatic
diameters of fetal skull
- suboccipito bregmatic (9,5cm)
- suboccipito frontal (10,5cm)
- occipitp-frontal (11,5cm)
- mento-vertical (13cm)
- submento-bregmatic (9,5cm)
positions of the fetal skull
- suboccipito bramati ( flexed vertex)
- suboccipito frontal (partial deflexed vertex)
- occipitp-frontal (deflexed vertex)
- mento-vertical (brow)
- submento-bregmatic (face)
types of fetal presentations
- vertex
- face/brow
- frank breech
- complete breech
- incomplete/flooting breech
- transverse
Considerations for normal labour
- The lie is longitudinal
- The presentation is cephalic
- The position is LOA or ROA
- The attitude is one of good flexion
- The denominator is occiput
- The presenting part is the posterior part of the parietal bone
Pelvic inlet diameters
Anterior-posterior diameter (API) = 11cm. The line between the narrowest points formed by the sacral promontory and the upper inner border of the symphysis pubis (=obstetrical conjugate)
Transverse diameter (TDI) = 13 cm. Taken between the widest points on the iliopectineal lines
pelvic outlet diameters
Anterior-posterior diameter (APO) = 13 cm. From the tip of the sacrum to the lower border of symphysis pubis
Transverse diameter (TDO) = 11 cm The line between the inner surfaces of the ischial tuberosities
Oblique diameters = 12 cm
names of sutures
- frontal
- sagital
- coronal
- lambdoid
names of fontanels
- anterior fontanel (bregma)
- posterior fontanel (lambda)
- sphenoid fontanel
- mastoid fontanel
what do each of the sutures connect
- frontal - joins the two frontal bones together
- sagital - joins the two parietal bones together
- coronal - joins the frontal bone to the two parietal bones
- lambdoid - forms the junction between the occipital and the two parietal bones
what is moulding
Overlapping (overriding) of the fetal skull bones during labour; movement of sutures and fontanelles
grades of moulding
0 – no moulding
1+ sutures are approximate
2+ reducible overlapping of sutures
3+ irreducible overlapping of sutures
what can moulding indicate
may be a sign of CPD
Fetal causes of a breech presentation
Congenital abnormalities e.g.. Hydrocephalus
Prematurity
Macrosomia
Multiple pregnancy
IUGR and IUFD
maternal causes of a breech presentation
- Pelvic abnormalities e.g. Pelvic tumours, contracted pelvis.
- Abnormal placentation like previae
- Uterine abnormalities e.g. Septate, fibroids
- Multiparity (lax abdominal muscles)
- Poly - oligohydramnios
vaginal breech delivery methods
- spontaneous breech delivery
- Assisted breech deliver (partial breech extraction)
- Breech extraction (total)
mechanisms of labour in breech presentation
- Descent and engagement
- Flexion (lateral)
- Internal rotation
- Flexion
Wigard-Martin’s method
- The baby’s body lies on the attendant’s left hand
- The middle finger is inserted into the baby’s mouth, the index and ring fingers on the maxillae to improve and maintain head flexion
- Suprapubic pressure is exerted by the right hand to deliver the fetal head
Mauriceau – Smellie – Veit’s method
- The baby’s body lies on the attendant and left hand
- The ring and index fingers of the other hand are placed across fetal shoulders while the middle finger is place on the occiput to maintain head flexion.
-Traction is exerted on the fetal shoulders
Burns-Marchall’s method
- The attendant stands with his left side against the patient’s right leg.
- Baby’s feet are held in the left hand
- Gentle traction is exerted with the legs lifted in a wide arc
- Delivery of the head is controlled with the right hand, with index and middle fingers placed on the cheek bones.
Lovset’s method
It is a combination of traction and rotation
complications of breech
- birth asphyxia (cord prolapse and presentation)
- birth injuries (brachial palsy, long bone fructures, spinal cord disruptions, tears in the tentorium cerebellum)
indications of C/S in breech
- EFW of more than 3700g or less than 1500g
- Contracted pelvis
- Footling breech
- Deflexed head
- Any other obstetric complications
what is a compound presentation
Compound presentation is prolapse of a fetal extremity into the lower uterine segment alongside the presenting part.
Occurs when an arm prolapses alongside
the presenting part. Both the prolapsed arm and the fetal head present in the pelvis
simultaneously.
what are the causes of compound presentation
- The ill-fitting presenting part predisposes to extremities prolapse:
- Prematurity
- Cephalopelvic disproportion
- Multiple pregnancies
- Polyhydramnios
- Abnormal lie (transverse)
what is the management of compound presentation
- Confirm the diagnosis by ultrasound or XR
- Establish fetal viability
- Allow vaginal delivery in previable fetuses.
- In viable fetuses perinatal outcome is better with caesarean section than vaginal delivery
Umbilical cord prolapse is a risk in compound presentations.
what is the prognosis of compound presentation
Perinatal mortality rates of about 25%. Prematurity, cord prolapse and traumatic vaginal delivery are the main causes
complete breech
both thighs and legs are flexed
frank breech
thigh flexed on the abdomen and both legs extended at the knee
