CTG Flashcards
How would you classify a suspicious CTG?
one non-reassuring feature, two reassuring features
How would you classify a pathological CTG?
2 or more non-reassuring features on CTG or one abnormal feature
What features of a CTG are used to classify whether it is normal, suspicious or pathological?
Variability, FHR, decelerations
What is an abnormal variability on CTG?
<5bpm for >50mins or >25 for >25mins
What is abnormal FHR on CTG?
<100 or >180
What is abnormal decelerations on CTG?
Late decelerations >30mins
Single deceleration lasting more than 3minutes
Variable decelerations with concerning features with >50% of contractions for 30 mins
How long does a single deceleration need to be for it to be classified as abnormal?
3 minutes
What are the features of a reassuring CTG trace?
variability - 5bpm-25bpm
FHR 110-160pm
Decelerations absent
When would a fetal heart rate be classified as non-reassuring on CTG?
100-109 or 161-180
When would variability be classified as non-reassuring on CTG?
<5bpm 30-60 mins
>25bpm 15-25mins
When would decelerations on CTG be classified as reassuring?
none or early
variable decelerations with no concerning features for <90mins
What are the descriptions of CTG features?
Reassuring, non-reassuring, abnormal
What are the categories of CTG?
Normal, suspicious, pathological
How would you classify a normal CTG?
All features are reassuring (HR 110-160, variability 5bpm-25bpm, decelerations absent or early or variable w/o concerning features for <90mins)
What is the normal range of variability for CTG?
5-25 bpm
What is increased variability of CTG?
> 25 bpm
What is decreased variability of CTG
<5pm
What is considered absent variability on CTG?
<2pm
What is the normal pH range of cord blood samples?
7.25-7.30
How would you classify a suspicious CTG?
1 non-reassuring feature + 2 reassuring features
How would you manage a suspicious CTG?
correct hypotension with IV fluids
Correct uterine hyperstimulation by either stopping oxytocin or adding a tocolytic (terbutaline)
maternal obs
obstetric/senior midwife review
How would you classify a pathological CTG?
1 abnormal feature
or
2 non-reassuring features
How would you manage a pathological CTG?
as for suspicious CTG - examine mother + get senior review + apply conservative measures for hypotension or uterine hyperstimulation
if no response - fetal scalp stimulation
if no response consider FBS or expediting delivery
When is urgent intervention required?
Acute bradycardia or single prolonged deceleration for >3 mins
What are reassuring features on CTG?
Baseline FHR 110-160
variability 5-25
Deceleration absent or early or variable for <90mins
What are non-reassuring features on CTG?
Baseline FHR 100-109 or 161-180
variablity <5 or >5
Decelerations variable >90mins, late decelerations, variable decels + concerning signs
What are abnormal CTG features on CTG?
Baseline FHR <100 >180
Variability <5 for >50 mins or >25 for >25mins or sinusoidal
acute bradycardia or decel for 3 mins
late decelerations for >30 mins
Variable decels with concerning characteristics >50% of contractions for 30 mins
What terms are used to describe decelerations?
Early, variable, late
What characteristics of variable decelerations are concerning?
lasting more than 60 seconds
reduced baseline variability within the deceleration
failure to return to baseline
biphasic (W) shape
no shouldering
What is shouldering referring to in an ECG?
It is a reassuring sign - a deceleration surrounded by an acceleration on either side i.e. acceleration before the deceleration and after
What does NICE recommend as a tocolytic?
terbutaline 0.25mg subcut - can cause maternal and fetal tachycardia
What are accelerations a sign of?
fetal movement - healthy and normal
Types of deceleration
Type 1 - early
Type 2 - late
Type 3 - variable
Signs of hypoxic ischemic encephalopathy postpartum
abnormal tone and feeding
alterations in consciousness
seizure
What is a sinosoidal sign suggestive of?
fetal distress/anaemia/chorioamnionitis
