Malpresentation/Malposition Flashcards
define malpresentation
the presenting part is not the vertex so includes the face, brow, shoulder and compound presentations and transverse lie.
define malposition
the incorrect positioning of the vertex so includes, OP, acynclitic or slight deflexion of the head
what is breech
a malpresentation or variant of normal presentation
why is presentation important?
in vertex presentation the presenting part is typically a sphere (9.5x9.5cm) which allows:
production of equal uterine contractions
production of equal cervical dilatation (with a well fitting PP)
the membranes will remain intact for longer
the cord will not prolapse
maternal factors causing malpresentation
uterine abnormalities (septum, bicornate) pelvic mass pelvic shape anticonvulsant therapy drug/alcohol abuse multiparity
fetal factors causing malpresentation
IUGR
IUFD
congenital abnormalities: anencephaly, hydrocephalus, myelomeningocele, prader-willi syndrome
materno-fetal factors causing malpresentation
preterm delivery, placental position, multiple pregnancy, previous history of malposition, polyhydramnios, oligohydramnios
What is the correct term for face presentation?
mento anterior position, submentobregmatic diameter
what is the correct term for brow presentation?
occiptiomental diameter.
what is the most frequent malposition?
OP
what are the risk factors for OP?
nulliparity and maternal age over 35
how is OP diagnosed in pregnancy?
abdominal palpation abdomen appears flattened saucer shaped depression below umbilicus fetal back felt away from the midline fetal limbs easily felt fetal head usually high FHR heard high or at flank USS
what is short rotation?
15% cases occiput rotates through 45 degrees into the hollow of the sacrum
head descends into the lower pelvis in this position
this is direct/persistant OP
associated with anthropoid pelves
what is long rotation?
65% cases fetal head descends with some degree of flexion
occiput rotates in mid pelvis through 135 degrees to lie behind symphysis pubis
delivery as OA
increased incidences due to use of oxytocics to amplify uterine contractions
how to optimise fetal position antenatally?
hands and knees gorilla stomp pelvic rocking avoid soft chairs for long periods of time sitting astride dining room chair
what comfort measures can you do for an OP position?
counter pressure
heat/cold packs
bath or shower
movement, dancing, swaying, walking, on birth ball
how can you help baby turn in labour?
early diagnosis exaggerated simms position left lateral with elevated right leg delay ROM for as long as possible upright positions - pool or birth ball is best ??epidural
complications surrounding persistent OP
Lengthens labour by 1 hour for Multiparous and 2 hours for Primiparous – fetal and maternal distress
Increased pain during labour – back pain and iliac fossa pain especially
Prolapsed cord- ill fitting presenting part and early SROM.
Retention of urine (sinciput presses the urethra and bladder neck against symphysis pubis)
Shape of maternal pelvis/coccyx and fetal spine/occiput makes rotation problematic
Reduces natural mechanism’s ability for flexion (pelvis bones and muscles)
complications of OP
Increased pain especially in the back
Prolonged latent phase
Deep transverse arrest
Increased use of pharmacological anaesthesia/analgesia
Prolonged 1st and 2nd stage
Increased moulding and caput (=misdiagnosis of PP)
Premature urges to push before full dilatation (maternal exhaustion)
Oedema to the cervix due to premature pushing
Increased chance of instrumental delivery
Increased chance of trauma to the vaginal tract
Psychological trauma
role of the midwife with an OP positioned baby
linking the clues
informing mother of pain relief and coping mechanisms
