Prenatal Assessment Of Fetal Well Being Flashcards
(41 cards)
False positive test
Abnormal test that prompts untimely delivery but not associated with evidence of fetal compromise
False negative test
Fetal death occurs within a week of a normal antepartum test
Antepartum fetal monitoring
1- screening tests
2- specific tests
Screening tests
1- fetal movements
2- symphysiofundal height
Fetal movements are felt by mother in which trimester
Second trimester
What is quickening
It is the first movement perceived by the mother
Frequency of normal fetal movements
Greater than 10 times per hour. No of times the mother perceives it in one day are from 10-1000
Which week is the fetal activity greatest
28- 32 weeks
Hours at which activity is greatest
9 pm to 2 am
Cardiff count to ten kick chart
Start counting at 9 am and count atleast 10 kicks by 9 pm otherwise consult doctor
Other methods of fetal movements assessment
Daily counting at the same time for the 1 hour. If 10 are counted all is fine. If not count for another 1 hour. Less than 10 kicks in 2 hours go to doctor
Another method (2)
Fewer than 4 kicks in 30 minutes, go to doctor
Non stress CTG
Ctg performed in the antenatal period without any stress
Requirements of CtG
Abdominal probe and pressure gauge
Components of cTG
Tocogram and cardiogram
CTG variables
1- baseline fetal heart rate
2 - fetal heart rate variability
3- accelerations
4- decelerations
Effect on CTG by fetal nervous system maturation (28-32 weeks)
Before nervous system maturation there is high baseline fetal heart rate and low variability
2- fetus develops periods of quiet sleep
Quiet sleep phase of fetus
Lasts for 20-30 minutes and has absence of fetal movements, absence of accelerations and low fetal heart rate variability
Fetal heart rate in prolonged pregnancy
Less than 110 beats per min
Normal fetal heart rate
135 beats per minute
Range of 110 to 150 beats per min
Less than 110 is bradycardia
Greater than 150 is tachycardia
Effects of acute hypoxia on fetal heart rate
Bradycardia due to vagal stimulation.
May get normal due to sympathetic stimulation. It also causes peripheral vasoconstriction
Chronic hypoxia on fetal heart rate
Remains normal
Non hypoxic bradycardia
Prolonged pregnancy. Fetal heart block. Maternal hypothyroidism. Maternal hypoglycaemia. CMV. Beta blockers. Local anesthetic drugs injected into blood vessels
Non tachycardic hypoxia
Fetal prematurity. Anemia. Maternal anxiety. Hyperthyroidism. Pyrexia. Beta sympathomimetics. Para sympatholytics.