10.2 Flashcards
What are the three elements of labour that need to be considered when there is failure to progress in labour? Give examples
Power - Insufficient uterine contraction Passage - Abnormal bony pelvis, rigid perineum Passenger - Fetus too big, breech position
How can power be assessed?
Uterine contraction can be assessed in terms of frequency, amplitude and duration.
Significance of passenger in labour
Size of passenger
Number
Position
What forms the passage?
Bony pelvis and soft tissues.
What are the diameters of the bony pelvis?
Pelvic inlet 10.5 cm
Pelvic cavity 12 cm
Pelvic outlet 11cm
What are the different ways a fetus can lie?
Transverse lie
Longitudinal lie: Flexion - head flexed Extension - head extended Breech - feet first - Frank - legs extended towards head - Full - cross legged - Single footling - one foot out
What is the most common position in which a baby lies?
Longitudinally, in a cephalic presentation, well flexed so vertex present to pelvic inlet.
Diameter = 9.5cm
How can the physiological state of the fetus be monitored during labour?
The fetal heart rate can be assessed using a fetal scalp electrode.
Options when labour gets stuck
Cesaerian section or operative delivery.
What instruments can be used in operative delivery?
Forceps
Vaccuum extraction
Where is a caesarian section made?
Suprapubic/hypogastric incision
Describe a C section cut.
Linea alba and anterior layers of rectus sheath are transected and resected superiorly.
Rectus muscles are retracted laterally or divided through their tendinous parts allowing attachment without muscle fibre injury.
What are the effects of oestrogen on oxytocin receptor production in the myometrium?
Increases.
What effect does progesterone have on the responsiveness of uterus to oxytocin and prostaglandin release?
Reduces effect.
Why is progesterone required to avoid spontaneous abortion?
Prevents oxytocin from evoking contraction during pregnancy and Ferguson’s reflex.
(Before 24 weeks)
