interpretation of CTG

1. CTG Interpretation

2. Interpretation of CTG trace
• Make a documentation of condition of woman & fetus every hour or more frequently if
there are concerns.
• Do not make any decisions about a womans care in labour on the basis of CTG findings
alone.
• Ensure focus of care remains on the woman rather than the trace.
• Document contractions & 4 features of fetal heart rate—baseline rate,baseline
variability,presence or absence of decelerations & presence of accelerations.
• If fetal heart rate is between 110 & 160 & normal variability ,continue usual care as risk of
fetal acidosis is low.
• In case of any difficulty obtain a review by a senior midwife or a senior obstetrician.
• Presence of fetal heart rate accelerations ,even with reduced baseline variability is
generally a sign that the baby is healthy.

11. Conservative measures
Encourage the woman to mobilise or adopt an alternative position-avoid supine position.
Offer IV fluids if hypotensive
Reduce contraction frequency –reduce or stop oxytocin /offering a tocolytic-SC terbutaline 0.25 mg.
Intrauterine resuscitation-do not use facial O2 therapy –may harm the baby.
Can be used for maternal indications like hypoxia or preoxygenation for anaesthesia.
Do not offer amnioinfusion for intra-uterine fetal resuscitation.
Fetal scalp stimulation-contraindications-fetal bleeding disorders or risk of maternal to fetal transmission of
infection.
Do not do –in acute event like cord prolapse/suspected placental abruption/suspected uretine rupture.
Do not do—if clinical picture indicates that birth shud be expedited.
Sepsis or significant meconium-FBS maybe falsely reassuring

12. Fetal blood sampling
• Do not take sample immediately after a prolonged deceleration.
• Take sample with woman in LLP.
• Use either Lactate or pH for interpretationlactate
FBS borderline-no accelerations after scalp stimulation-take a 2nd sample no more than 30 mins
later if indicated by CTG.
• FBS-normal & no accelerations after scalp stimulation-take a 2nd sample no more than 1 hr if
indicated by CTG.
• FBS-abnormal—expedite the birth
pH lactate
normal 7.25 or
above
4.1 mmol/L or below
borderlin
e
7.21 -7.24 4.2 to 4.8
abnormal 7.20 or
below
4.9 or more

23. First stage of labour
Primis-avg 8-18 hrs
Multis-5-12 hrs.
Observations-
Contractions-1/2 hrly
Pulse –hourly
Temperature & BP—4 hrly
Vaginal exam –4 hrly or if any concern about progress .
Delay in 1st stage-cervical dilatation less than 2 cm in 4 hrs
Descent & rotation of babys head
Changes in strength,duration & frequency of uterine contractions
Consider amniotomy for women with intact membranesvaginal exam after 2 hrsdelay if
progress <1 cm

24. Oxytocin use-vaginal exam 4 hrs after starting cervical dil <2 cm after 4 hrs—obstetric review
if cervical diln >2 cm –4 hrly vaginal exam.
Oxytocin will increase frequency & strength of contractions
Will forward time of birth but will not influence the mode of birth or other outcomes
Time in between increments of dose-every 30 mins until 4-5 contractions in 10 mins.
Definition of 2nd stage-
Passive-full dilatation of cervix before or in absence of involuntary expulsive contractions
Active stage—baby is visible
Expulsive contractions
Active maternal effort
Observations-frequency of contractions-1/2 hrly
BP -1/2 hrly.temp-4 hrly,frequency of voiding
Vaginal exam-hourly in active stage or in response to womans wishes

25. IA of FHR immediately after a contraction for atleast 1 min, at least every 5 mins.
Duration of 2nd stage-
Nullipara-3 hrs of start of active 2nd stage.
Multipara-2 hrs of start of active 2nd stage
Third stage-from birth of the baby to expulsion of placenta & membranes.
Prolonged –with active mgt -30 mins
Physiological mgt-60 mins

26. Heart disease
Mgt of anticoagulation for women with mechanical heart valves-women on warfarin in 3rd trimester
Switch to LMWH by 36W of pregnancy or 2 w prior to planned birth.
Stop warfarin  24 hrs later start LMWH twice daily
Check that anti-Xa level is above 0.6 IU/ml before inj of LMWH
Planned caesarean section- stop LMWH 24 hrs prior-perform surgery as near to 24 hrs after
stopping & no later than 30 hrs.
Or-switch to UFH ,then 4-6 hrs before caesarean stop UFH .
Post partum period—aim to restart therapeutic LMWH or UFH 4-6 hrs after birth.
Consider delaying restarting warfarin 7 days after birth
Mode of birth- consider planned caesarean section for
Any disease of aorta assessed as high risk
Pulmonary arterial HT
NYHA class III or IV

27. Fluid mgt-fluid balance is critical in
severe left sided stenotic lesions
hypertrophic cardiomyopathy
Cardiomyopathy with systolic ventricular dysfunction
Pulmonary arterial HT
Fontan circulation
NYHA class IV
Monitor
Hourly monitoring of fluid input & output,BP,pulse,RR & O2 saturation
Continuous ECG & pulse oximetry
Continuous intra-arterial BP monitoring

28. Anaesthesia & analgesia for women with heart disease
Consider collaborative working between obstetric anaesthetist & cardiac anaesthetist for women with
modified WHO 3 & modified WHO 4 heart disease.
Offer low dose RA to women with modified WHO 3 or 4 –less likely to cause cardiac instability during labour
& birth.
For women on LMWH
Wait 12 hrs after prophylactic dose –before EA or removing the catheter
Wait 24 hrs after therapeutic dose
Wait 4 hrs after EA or SA or removing epidural cath to give dose of LMWH
Do not administer therapeutic dose of LMWH while epidural cath is in situ
Mgt of 3rd stage –women with modified WHO 3 or 4 heart disease.
Marfan syndrome/Turners/Aortic dissection-avoid ergometrine
Severe valvular stenosis/Fontan /cyanotic heart disease-avoid long acting oxytocin analogues & ergometrine