Electronic Fetal Heart Rate Monitoring AKA “reading strips” G1 OB skills workshop- July 31st 201

Goals Become familiar looking at electronic fetal heart rate tracings Learn a systematic approach to electronic fetal monitoring (EFM) interpretation

Objectives List the three risk based categories of EFM interpretation Demonstrate an organized approach to reading a strip Correctly identify early decelerations, variable decelerations, late decelerations

EFM: The Basics Used to assess fetal well being External vs. internal monitoring Intermittent vs. continuous monitoring Constant and minuute adjustments in response to the fetal environment and stimuli

EFM: The Basics FHR tracings should be evaluated in the context of the clinical situation. This includes (but is not limited to): Gestational age Prior results of fetal assessment Medications Maternal medical conditions Fetal conditions

External monitors

Internal monitors-IUPC and FSE

Systematic approach Baseline fetal heart rate and trend variability Uterine contractions (frequency and duration) Periodic Heart Rate Changes Accelerations and Decelerations Changes or trends over time

DRCBRAVADO (ALSO mnemonic) Define Risk Contractions (in 10 mins) Baseline Rate (should be 110-160) Variability (should be greater than 5) Accelerations Decelerations Overall (normal or not)

Systematic Approach Final interpretation Category I Category II Category III Develop an assessment and plan and DOCUMENT it

Categories A new classification system from the 2008 National Institute of Child Health and Human Development Workshop Report Based on available evidence and consensus statements

Key Guidelines FHR decels as an independent finding are poorly predictive of complicated outcomes The degree of variability is the MOST sensitive indicator of the adequacy of oxygen delivery to the fetus at any given moment in time

Pattern Evolution Recognizing changes in the FHR tracing over time is the key element of FHR interpretation. A hypoxia-induced reduction in FHR variability develops gradually over about 60-120 minutes

Progress Note Example Subjective Objective Toco: baseline 130s, good variability reactive, occ. variable deceleration Ctx: q 3 min., regular, palpate moderate intensity Cervix: 5/80/-1 A/P: G3P2 at term. Category 1 tracing. Expectant management. Anticipate NSVD.

Contractions The number of contractions present in a 10 minute window averaged over 30 minutes. Normal: less than or equal to 5 Tachysystole: more than 5 Avoid the terms “hyperstimulation” and “hypercontractility”

Category I-Normal Baseline rate between 110-160 bpm Moderate baseline variability May lose variabilty for 30-40 minutes during fetal sleep cycles. This is OK. Accelerations present (or absent) Early decelerations may be present No late or variable decelerations

Moderate Variability

Variability Classifications-Detemined in a 10 min window excluding accelerations and decelerations Absent: amplitude range undetectable Minimal: amplitude more than undetectalbele and less than 5 bpm Moderate amplitude range 6-25 bpm Marked: amplitude range >25 bpm

Accelerations

Accelerations Reliably predict the absence of fetal maetabolic acidemia However…REMEMBER the absence off accelerations does NOT reliably predict fetal acidemia.

Early Decelerations

Early Decelerations

Category II-The Messy Middle Fetal tachycardia (>160 bpm) Fetal bradycardia (<110 bpm) With preserved baseline variability Minimal or Marked baseline variability Absence of induced accelerations after fetal stimulation

Category II Variable decelerations associated with minimal or moderate variability Variable Decels with shoulders Late decelerations with preserved moderate baseline variability Prolonged decelerations (greater than 2 minutes, but less than 10)

Category II Tracings If you have a category II tracing you need to do something to try and make it better. Oxygen, change in position, d/c pitocin, etc. Consider making the OB team aware of the situation as well.

Category II INDETERMINATE Not predictive of abnormal fetal acid base status, yet no adequate evidence to classify as Category I or III.

Fetal Tachycardia

Fetal Bradycardia

Late Decelerations

Variable Decelerations with Shoulders

Saltatory variability

Category III - Abnormal Absent baseline varibility and any of the following: Recurrent late decelerations Recurrent variable decelerations Bradycardia Sinusoidal pattern

Category III FHR tracing with persistent absent or minimal variability with recurrent decels or bradycardia hold the strongest association with fetal acidemia and/or the absence of neonatal vigor at birth

Ominous tracings Usually requires IMMEDIATE delivery if the tracing is persistently a category III If vaginal delivery is close, move to operative vaginal delivery. If vaginal delivery not imminent, then a c-section is needed.

Decreased Variability

Late Decelerations with absent variability

Sinusoidal pattern

Now it’s your turn…..

Practice Fetal tachycardia, loss of varibility, small variable decels

Practice Reacitve strip, no contractions

Practice

Practice Pseudosinusoidal pattern- non-reassuring but not ominous

Objectives List the three risk based categories of EFM interpretation Demonstrate an organized approach to reading a strip Correctly identify early decelerations, variable decelerations, late decelerations