Obstetrics 2 - Pregnancy Problems 1 Flashcards
Define malpresentation
Any presentation other than a vertex lying in close proximity to the internal os of the cervix
Give three causes of malpresentation
Multiparity Prematurity Multiple pregnancy Macrosomia Polyhydramnios Placenta praevia
What is brow presentation?
Head occupies a position between full flexion (vertex) and full extension (face)
What is the management of brow presentation?
Diagnosis via VE
May revert to face/vertex
Vaginal delivery not possible - CS if it persists
What causes face presentation?
Hyperextension of the foetal neck
What are the two types of face presentation?
Mentoanterior and mentoposterior
What is the management of face presentation?
Mentoposterior - CS
Mentoanterior - head can flex to allow vaginal birth, if not then CS
What is cord/funic presentation?
One or more loops of cord lie below the presenting part with membranes still intact
What indicates cord presentation on the CTG?
Persistent variable decelerations
What is contraindicated in cord presentation and why?
Artificial rupture of membranes will cause cord prolapse
What is abnormal lie?
The axis of the foetus is across the axis of the uterus
What is unstable lie?
Lie changes several times a day, variable presentation
What are the causes of abnormal lie?
Multiparity, multiple pregnancy, polyhydramnios, placenta praevia, fibroids
What are the risks of abnormal lie?
Obstructed labour
Uterine rupture
What is the management of abnormal lie?
Unstable lie - CS at 41 weeks
Stable abnormal lie - CS at 39w
May revert - common before term but only 1% foetus after 37 weeks
What is breech presentation?
Baby’s buttocks lie over the maternal pelvis and head is in the fundus
Give three causes of breech presentation
Idiopathic Preterm delivery Previous history of breech delivery Fibroids Placenta praevia
What are the three types of breech presentation?
Extended, flexed, footling
What is the management of breech presentation?
External cephalic version Caesarian section (esp. if footling) Vaginal birth (without oxytocin) only if foetal weight <4kg, no foetal compromise, extended breech, spontaneous labour
What is the name of the condition where the placenta is inserted into the lower segment of the uterus?
Placenta praevia
How does placenta praevia present?
10% asymptomatic
70% painless APH
20% APH associated with contractions
What are the risk factors for placenta praevia?
Previous PP
Increased maternal age
Multiparity/multiple pregnancy
CS
What grade of placenta praevia is a placenta that partially covers the internal cervical os?
Partial
What is the difference between minor (marginal) (grade I or II) and major (grade III or IV) placenta praevia?
Minor - placenta lies close to cervical os
Major - placenta completely covers the cervical os
How is placenta praevia diagnosed?
Transvaginal ultrasound
What is the management of placenta praevia diagnosed in the 2nd trimester?
Repeat ultrasound at 30-32 weeks as PP can resolve with development of the lower uterine segment
What is the management of a patient with a major placenta praevia, who is experiencing some bleeding?
Admit from 34 weeks and determine foetal lung maturity with amniocentesis
CS if lungs are mature
What occurs when the placenta completely separates from the uterus before delivery of the foetus?
Placental abruption
How does placental abruption present?
Severe constant abdominal pain Woody tender uterus 50% in labour Dark bleeding Maternal shock and hypovolaemia
What are the risk factors for placental abruption?
Maternal hypertension Previous abruption IVF pregnancy Short umbilical cord Polyhydramnios
Why may the extent of bleeding in placental abruption be greater than apparent loss?
Concealed haemorrhage (20%) - blood goes upwards towards the fundus
What is the management of placental abruption?
AB: high flow oxygen
C: IV access, FBC, coagulation screen, U&E, Kleihauer test, Crossmatch 4 units. Left lateral position. Until blood is available: 2L warmed crystalloid Hartmann’s or 1-2L colloid. Up to 4 units FFP and 10 units cryoprecipitate
D: Alive foetus: Caesarian
What is the most common cause of DIC in pregnancy?
Placental abruption
What is the main complication of placental abruption?
Foetal hypoxia/neurological impairment and death
Define retained placenta.
Placenta not delivered within 30 minutes of active management or 1 hour of physiological management
What are three causes of retained placenta?
Trapped behind closed cervix, placenta adherens, partial placenta accreta
What is the management of retained placenta?
Revert to active management
Empty bladder
Rub uterus and VE to see if placenta has detached
Manual removal followed by IV and IM ergometrine
What indicates placental separation in the third stage of labour?
Sudden rush of blood, fundus moves higher and becomes more rounded, increased length of cord visible.
Name three placental conditions which increase the likelihood of retained placenta.
Succenturiate lobe, bipartite placenta, placenta membranacea
What is placenta accreta?
Chorionic villi are attached to the myometrium
What is placenta increta?
Chorionic villa have invaded the myometrium
What is placenta percreta?
Chorionic villi pass through the myometrium up to the serosa/peritoneum
What is Nitabuch’s layer?
Fibrinoid deposits that occur between the compact and spongy layer of decidua basalis. Incomplete development in placenta accreta.
What is the management of severe haemorrhage in a woman with placenta accreta?
ABCDE. Replace blood, tamponade with balloon, hysterectomy
What is the management of minimal haemorrhage in a woman with placenta accreta?
Uterine artery embolization, elective hysterectomy
Define primary postpartum haemorrhage
Blood loss >500ml from the genital tract within 24 of delivery (or >1000ml after CS)
Define secondary post-partum haemorrhage
“excessive blood loss” between 24h and 12w after delivery
What is the most common cause of PPH?
Uterine atony
Apart from uterine atony, give three causes of PPH
Genital tract trauma Retained placenta Abnormal placenta site Uterine inversion/rupture DIC
What are three risk factors for uterine atony?
Vitamin D deficiency
Prolonged labour
Overdistension of the uterus - multiple pregnancy, polyhydramnios, macrosomia
What is the most likely cause of secondary PPH?
Disruption of placental site scab/placenta fragments
Subinvolution of the uterus
What is uterine atony?
Failure of the uterus to contract after placental separation, allowing bleeding to occur from myometrial spiral arterioles and decidual veins
What peptide is released in uterine atony to cause uterine relaxation?
Parathyroid hormone-related peptide
How do you prevent PPH?
Vaginal delivery: 5-10IU IM oxytocin
Caesarian: IV oxytocin for 6h
Inspect vagina and perineum for lacerations
Assess placenta for missing cotyledons
What is the treatment of PPH?
Resuscitation with ABCDE approach. 2x14 gauge cannulae, cross match 4 units, blood transfusion (2L warmed crystalloid Hartmann’s +/- 1-2L colloid whilst waiting)
If uterine atony, the following in order:
Bimanual uterine compression
Slow IV Oxytocin 5IU
Slow IV or IM ergometrine 0.5mg
IM carboprost 0.25mg (repeat up to 8 doses)
PR misoprostol
Balloon tamponade/B-lynch suture/bilateral ligation of uterine or internal iliac arteries
Why might a woman choose home birth?
Familiar setting
Fear of hospitals
More family members
What are the risks of home birth?
If a complication arises, transfer to hospital is advisable but may be delayed, which can lead to intrapartum foetal hypoxia or PPH.
What is an anomaly scan?
Detailed ultrasound scan at 20 weeks
Define antepartum haemorrhage
Bleeding from the genital tract <24 weeks, before the onset of labour
What is the main cause of antepartum haemorrhage?
97% unexplained, usually minor placental abruption
Other - PP, infection, trauma, varicosities
True or false, APH is painless
False - can be painful or painless
What is the management of APH?
Estimate amount of blood loss and combine with signs of clinical shock
Resuscitation if necessary
If rhesus negative give 500IU anti-D Ig
Determine local causes of bleeding/if membranes have ruptured with VE
Exclude placenta praevia with TVUSS
Mother’s life should take priority but foetal distress = delivery regardless of gestational age
Why do pregnant women experience more constipation and heartburn?
Increased progesterone levels causes the relaxation of the gastro-oesophageal sphincter and bowel smooth muscle
What is the cause of backache in pregnancy?
Hormonal softening of ligaments and altered posture due to weight of uterus