It's beat to beat changes in the HR. Meaning the HR is just just consistently 140--> changes beat to beat from 140- 145- 152-143-138. Means the fetus is well-oxygenated. If not well oxygenated--> fetus doesn't want to move to conserve oxygen and you'll have less variability
What's the difference between short-term and long-term?
Short term--> no longer really used but is exact beat-beat change
Long term--> rhythmic flucations in FHR (3-5 cycles per min) Easier to determine visually looking a strip.
What is suggested with absent variability?
omnious--> decreased fetal oxygenation or CNS insult or disorder
What does decreased variability suggest?
-fetal cardiac arrhythmias
What are 2 causes of sinusoidal rhythm?
1. Narcotics (morphine/stadol)
2. Rh isoimmunized (impending death--> stat c-section)
What are the 4 types of variability?
What is the signficance of FHR acceleration?
Reassuring that fetus is well-oxygenated at that moment
-Has to be >15bpm above baseline for 15min
-Associated with fetal movement/contractions
What is the clinical significance for variable decelerations?
-common, usually transient and associated with cord compression (NOT associated with poor outcomes)
-Mild (<30bmp below baseline)
-Mod (<50bpm below baseline)
-Severe (<70bmp, slow return to baseline)
**Abrupt return to baseline is a reassuring sign of good oxygenation despite cord compression
What is the clinical signficance of early decelerations?
-Associated with head compression
-FHR is mirror image of contraction or starts decreasing just before contraction visualized
What is the clinical significance of late deceleration?
-Ominous when persistant or uncorrectable. Most worrisome w/ tachycardia and no variability
-Late decels suggest uteroplacental INSUFFICIENCY
What do late decelerations suggest?
-fetal hypoxia, metabolic acidosis
What is the clinical significance of prolonged decel (>90sec)?
-Decreased oxygenation, poor prognosis
-If doesn't return to baseline in 2min--> usually expedite delivery--> forceps/vacumn or c-section