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CTG. The first central concept of standardized intrapartum FHR interpretation is that all clinically significant FHR decelerations (variable, late, or prolonged) reflect interruption of the pathway of oxygen transfer from the environment to the fetus at 1 or more points.
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The first central concept of standardized intrapartum FHR interpretation is that all clinically significant FHR decelerations (variable, late, or prolonged) reflect interruption of the pathway of oxygen transfer from the environment to the fetus at 1 or more points . mcu pgc '10
The second central concept of standardized intrapartum FHR interpretation is that intrapartum interruption of fetal oxygenation does not result in CP unless the fetal response progresses to the stage of significant fetal metabolic acidemia(umbilical artery pH <7.0 and base deficit ≥12 mmol/L). mcu pgc '10
The third central concept of intrapartum FHR interpretation is that moderate (normal) variability and / or accelerations reliably predict the absence of fetal metabolic acidemia at the time they are observed. mcu pgc '10
Category I: NORMAL • FHR tracings include ALLof the following: • Baseline rate: 110–160 beats per minute (bpm) • Baseline FHR variability: moderate • Late or variable decelerations: absent • Early decelerations: present or absent • Accelerations: present or absent • Strongly predictive of normal acid-base status at time of observation. • Routine care; no specific action required mcu pgc '10
Category III: ABNORMAL • FHR tracings include EITHER of the ff: • Absent baseline FHR variability andany of the ff: • Recurrent late decelerations • Recurrent variable decelerations • Bradycardia • Sinusoidal pattern mcu pgc '10
Category II: INDETERMINATE • includes all FHR tracings NOT categorized as Category I or III. • NOT predictive of either normal or abnormal fetal acid-base status. • requires continued surveillance and re-evaluation- second recommendation is incomplete mcu pgc '10
TERMINOLOGIES mcu pgc '10
Grades of fluctuation are based on amplitude range (peak minus trough): mcu pgc '10
Classifications of Variability • Absent: amplituderange undetectable. • Minimal: amplitude range ≤5 bpm. • Moderate: amplituderange 6-25 bpm. • Marked: amplitude range >25 bpm. mcu pgc '10
110 BPM mcu pgc '10
160 BPM mcu pgc '10
From the onset of the deceleration to the beginning of the FHR nadir of <30 seconds. The decrease in FHR is ≥15 beats per minute, lasting ≥15 seconds, and <2 minutes in duration mcu pgc '10
Variable Decelerations • Severe • ≥ 60 seconds in duration & < 70 beats/min OR • ≥ 2 mins in duration & < 80 beats/min • Moderate • 30-60 sec in duration & < 70 beats/min OR • ≥ 60 sec in duration & < 80 beats/min • Mild • All other decelerations are mild mcu pgc '10
Variable Decelerations - Notice that the decelerations are not related to the contraction, beginning well before the contraction even begins. mcu pgc '10
from the onset to the nadir of the deceleration of ≥30 seconds. The nadir of the deceleration occurring after the peak of the contraction. In most cases, the onset, nadir, and recovery of the deceleration occur after the beginning, peak, and ending of the contraction, respectively. mcu pgc '10
Late Deceleration with Absent Variability – • Notice the decrease in the fetal heart rate only begins to decline after the contraction peaks. mcu pgc '10
from the onset to the FHR nadir of ≥30 seconds. The nadir of the deceleration occurs at the same time as the peak of the contraction. n most cases the onset, nadir, and recovery of the deceleration are coincident with the beginning, peak, and ending of the contraction, respectively. mcu pgc '10
Pseudo-sinusoidal Pattern mcu pgc '10