Flashcards in PACES: CTG interpretation Deck (19)
What is the normal range for foetal baseline HR on the CTG?
After how many weeks gestation can a CTG be reliably used?
Recall a physiological cause of sustained foetal tachycardia on the CTG
Prematurity (the HR will fall with maturity)
Recall 3 pathological causes of foetal sustained tachycardia on the CTG
Which prescription drug can cause sustained foetal tachycardia?
Salbutamol (and other beta agonists)
Recall 2 common and 2 very concerning causes of foetal bradycardia on CTG
Common: hypotension, post-dates
Very concerning: placental abruption, uterine rupture
What HR as baseline on the CTG is indicative of impending foetal demise?
How do you calculate baseline variability?
Distance between highest peak and lowest trough in a 1-min segment of the CTG trace
What is normal baseline variability?
5-25 beats/ min
What is the most common cause of reduced baseline variability?
How long may reduced baseline variability last before it becomes concerning?
How is an acceleration defined on CTG?
Rise in foetal HR >15 bpm for at least 15s
What is the expected number of accelerations on a CTG?
2 every 15 mins
What change in the CTG is most often seen with contractions?
How are decelerations defined on the CTG?
Fall in foetal HR of >15 bpm for more than 15 s
What are early decelerations?
Occur with contractions and return to normal by the end of the contraction
What is suggested by late decelerations?
What is suggested by variable decelerations?
Cord compression - especially in oligohydramnios