abnormal labour + delivery + ob emergencies part II

Question 1

RF for breech

Answer 1

greater parity
multiples
hydramnios
oligohydramnios
hydrocephalus
anencephalus
prev hx
uterine anomalies
pelvic tumour

Question 2

types of breech

Answer 2

frank - knees straigh

complete - knees bent

partial - footling/kneeling

Question 3

risks /w breech birth

Answer 3

birth trauma + asyphxia (head entrapment)
preterm delivery or IUGR
cord prolapse
placenta previa
fetal anomalies
uterine anomalies/tumour
multiples
operative delivery

Question 4

reason for head entrapment in breech delivery

Answer 4

less time for moulding

head biggest part

Question 5

management of breech position

Answer 5

• diagnose at 35-36wks
• ECV after 36 wks
• and/or planned CS
• ## or trial of vag breech birth

Question 6

risks of ECV

Answer 6

• abruption
• hemorrhage
• ROM
• labour
• fetal bradycardia
• cord accident
• allo-immunization (give Rhogam)

Question 7

selection criteria for vag delivery of breech

Answer 7

• pre or early labour US to assess type of breech (CS if unavailable)

CI if:

• cord presentation
• fetal growth restriction
• macrosomia
• not frank or complete
• inadequate maternal pelvis
• fetal anomaly (eg hydrocephalus)
• preg women refuses TOL

Can be offered if
- EFW 2500-4000g

Question 8

breech labour management

Answer 8

check for abnormal pelvic contraction

good progress = room likely, CS if not

cont FHR

check for prolapse when rupture

induction not recommended, oxytocin can be used

active second stage near OR

paeds team at delivery

CS if delivery not imminent after 60min pushing

Question 9

RF for shoulder dystocia

Answer 9

post-term
maternal obesity
fetal macrosomia
prev hx
operative vag delivery
prolonged labour
poorly controlled diabetes

Question 10

risks of shoulder dystocia

Answer 10

• PPH/uterine atony
• maternal laceration
• uterine rupture
• birth injury
• clavicle, humerus #
• brachia plexus injury
• hypoxic ischemic encephalopathy
• death

Question 11

maneuvers for shoulder dystocia

Answer 11

A - ask for help
L - lift legs (mcroberts)
A - anterior shoulder dysimpaction (suprapubic pressure + vag shoulder pressure)
R - rotate (woods corkscrew)
M - manual delivery of posterior arm
E - episiotomy (+ deliver arm)
R - roll onto all 4s

after this:
clavicle fracture
symphysiotomy
zavanelli maneuver

don’t

• pull
• pivot
• panic
• push on fundus

Question 12

delivery options for future preg after dystocia

Answer 12

risks and benefits discussed /w patient

review notes

TOL or CS options

Question 13

causes of poor oxygenation to fetus

Answer 13

maternal

• anemia
• carboxyhemaglobin
• hypotension
• regional anesthesia
• position
• vasculopathies (T1DM, SLE, HTN)
• antiphospholipid antibody

utero-placental

• hyperstim
• abruption
• infarction/oligohydramnios
• chorioamnionitis

fetal

• cord compression
• oligo
• cord prolapse, knots
• fetal hemaglobinopathy
• anemia (isoimmunization, fetomaternal bleed)

Question 14

definition of fetal asyphxia

Answer 14

diagnosed at birth, must have all of:

• apgar 0-3 for >5min
• neonatal neuro sequelae
• multi organ dysfunction in neonate
• UA pH <7.0 and base deficit >16

Question 15

pathophysiology and interpretation of acid/base

Answer 15

• respiratory acidosis normal, CO2 accumulates with cord compression, goes away /w first breaths
• metabolic acidosis is from hypoxia –> anaerobic metabolism and lactic acid, causes longer to develop + remit, potential for damage

Resp: increased PCO2 and normal base deficit

metabolic: N PCO2 and decreased base deficit
mixed: increased PCO2 and decreased base deficit

Question 16

pathophysiology and interpretation of acid/base

Answer 16

• respiratory acidosis normal, CO2 accumulates with cord compression, goes away /w first breaths
• metabolic acidosis is from hypoxia –> anaerobic metabolism and lactic acid, causes longer to develop + remit, potential for damage

Resp: increased PCO2 and normal base deficit

metabolic: N PCO2 and decreased base deficit (bicarb low)
mixed: increased PCO2 and decreased base deficit

Question 17

causes of fetal bradycardia

Answer 17

• maternal hypotension
• drugs
• fetal hypoxia (cord prolapse/compression, abruption, fetal hypotension, fetal hemorrhage)
• vagal stimulation
• fetal acidosis
• fetal cardiac conduction or structural defect

Question 18

causes of fetal tachycardia

Answer 18

maternal

• fever
• infection
• dehydration
• hyperthyroidism
• anxiety
• drugs
• anemia

fetal

• infection
• prolonged activity
• chronic hypoxemia
• cardiac abnormality
• congenital anomalies
• anemia

Question 19

variable decels causes

Answer 19

• vagal stimulation (head compression)
• cord compression
• complicated: fetal acidemia

Question 20

early decels causes

Answer 20

• vagal head compression

Question 21

late decels causes

Answer 21

• altered blood flow to placenta
• reduced mat O2 sat
• uterine hypertonus
• fetal acidemia

Question 22

decreased variability causes

Answer 22

• acidemia if /w decels
• maternal acidemia + analgesics can decrease variability
• occurs /w tachycardia

Question 23

normal intrapartum tracing

Answer 23

• baseline 110-160
• variability 6-25 or <5 for <40min
• decels: none or occasional uncomplicated variables or early decels
• accels: spont present, at minimum present /w scalp stim
  action: can interrupt FHR for 30 min if stable and oxytocin stable

no evidence of fetal compromise

Question 24

atypical intrapartum tracing

Answer 24

• bradycardia 100-110
• tachy >160 for 30-80 min
• rising baseline
• variability <5 for 40-80min
• decels: repetitive uncomplicated variables (3 in row), occasional (<2 in a row) complicated variables, intermittent lates, single prolonged decel 2-3min
• accels: none /w scalp stim
  action: vigilant assessment. Likely physiologic response.

Question 25

abnormal intra-partum tracing

Answer 25

• bradycardia <100bpm
• tachycardia >160 for >80min
• erratic baseline
• variability <5 for >80min
• > 25 for >10 min
• sinusoidal
• repetitive complicated variables:
• > 60s below baseline
• > 60s and <60bmp
• loss of variability
• biphasic
• overshoots
• slow return to baseline
• baseline lowers
• baseline tachy or brady
• late decels > 50% of contractions
• single prolonged decel >4min but <10min
• accels absent usually
  action: scalp pH and/or delivery

Question 26

management of abnormal/atypical tracing

Answer 26

• reposition
• maternal vital
• IV fluid bolus
• stop oxytocin
• O2 at 8-10 L/min
• rule out fever, dehydration, drugs, prematurity
• cont FHR
• fetal scalp sample if appropriate
• delivery if needed/persists

Question 27

fetal scalp sample intepretation

Answer 27

pH >7.25 normal

pH 7.21-7.24: cont, repeat in 30 mins or if change

pH <7.20 - deliver

for lactate:
<4.1
4.2-4.8
>4.8

Question 28

meconium significants

Answer 28

theories

• distress, hypoxia
• normal GI
• vagal stim from transient cord compression

aspiration can occur if acidemia

RF: post-term + IUGR

Question 29

mech aspiration risks to baby

Answer 29

• pulmonary hypertension
• mechanical airway obstruction
• chemical pneumonitis

Question 30

cord prolapse RF

Answer 30

• malpresentation
• prematurity
• anomalies
• multiples
• polyhydramnios
• premature ROM
• AROM
• placenta previa
• high presenting part
• ECV

Question 31

management of cord prolapse

Answer 31

1) assess viability: no cord pulsations, lethal anomaly, or too immature to survive –> deliver vaginally, CS if CI (eg transverse lie)
2) relieve cord compression, replace into vagina, elevate presenting part, adjust mom in trendelenburg
3) if fully dilated and low: assisted vag delivery, otherwise immediate CS