CTG

04/19/2023 mcu pgc '10 2

04/19/2023 mcu pgc '10 3

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 .

04/19/2023 mcu pgc '10 4

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).

04/19/2023 mcu pgc '10 5

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.

Category I: NORMALFHR tracings include ALL of the following:

Baseline rate: 110–160 beats per minute (bpm)Baseline FHR variability: moderateLate or variable decelerations: absentEarly decelerations: present or absentAccelerations: present or absent

Strongly predictive of normal acid-base status at time of observation.

Routine care; no specific action required

04/19/2023 7mcu pgc '10

Category III: ABNORMALFHR tracings include EITHER of the ff:

Absent baseline FHR variability and any of the ff: Recurrent late decelerations Recurrent variable decelerations Bradycardia

Sinusoidal pattern

04/19/2023 8mcu pgc '10

Category II: INDETERMINATEincludes 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

04/19/2023 9mcu pgc '10

TERMINOLOGIES

04/19/2023 mcu pgc '10 10

VARIABILITY

04/19/2023 12

Grades of fluctuation are based on amplitude range (peak minus trough):

mcu pgc '10

04/19/2023 13

Classifications of VariabilityAbsent: amplitude range undetectable.

Minimal: amplitude range ≤5 bpm.

Moderate: amplitude range 6-25 bpm.

Marked: amplitude range >25 bpm.

mcu pgc '10

BASELINE FHR PATTERNS

04/19/2023 15mcu pgc '10

04/19/2023 16

110 BPM

mcu pgc '10

04/19/2023 17

160 BPM

mcu pgc '10

Variable Deceleration

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

04/19/2023 19mcu pgc '10

Variable DecelerationsSevere

≥ 60 seconds in duration & < 70 beats/min OR≥ 2 mins in duration & < 80 beats/min

Moderate30-60 sec in duration & < 70 beats/min OR≥ 60 sec in duration & < 80 beats/min

MildAll other decelerations are mild

04/19/2023 20mcu pgc '10

04/19/2023 21mcu pgc '10

04/19/2023 22

Variable Decelerations - Notice that the decelerations are not related to the contraction, beginning well before the contraction even begins.mcu pgc '10

Late Deceleration

04/19/2023 24

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

04/19/2023 25mcu pgc '10

04/19/2023 26

Late Deceleration with Absent Variability – Notice the decrease in the fetal heart rate only begins to decline after the contraction peaks. mcu pgc '10

Early Deceleration

04/19/2023 28

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

04/19/2023 29mcu pgc '10

04/19/2023 30mcu pgc '10

Sinusoidal Pattern

04/19/2023 32mcu pgc '10

04/19/2023 33Pseudo-sinusoidal Pattern

mcu pgc '10

Thank you!