Chapter 17: Fetal Assessment during Labor Chapter 17 Fetal Assessment during Labor Mosby items and derived items © 2006 by Mosby, Inc. 1 of 30 Chapter 17: Fetal Assessment during Labor Fetal Assessment during Labor Electronic fetal monitoring (EFM) useful tool for visualizing FHR patterns on monitor screen or printed tracing Mosby items and derived items © 2006 by Mosby, Inc. 2 of 30 Chapter 17: Fetal Assessment during Labor Basis for Monitoring Fetal response Labor is a period of physiologic stress for fetus Frequent monitoring of fetal status is part of nursing care during labor Fetal oxygen supply must be maintained during labor to prevent fetal compromise Mosby items and derived items © 2006 by Mosby, Inc. 3 of 30 Chapter 17: Fetal Assessment during Labor Basis for Monitoring Fetal oxygen supply can decrease: Reduction of blood flow through maternal vessels as result of: • Maternal hypertension: chronic hypertension or pregnancy-induced hypertension • Hypotension caused by supine maternal position, hemorrhage, epidural analgesia or anesthesia • Hypovolemia caused by hemorrhage Mosby items and derived items © 2006 by Mosby, Inc. 4 of 30 Chapter 17: Fetal Assessment during Labor Basis for Monitoring Fetal oxygen supply can decrease: (cont’d) Reduction of oxygen content in maternal blood as result of hemorrhage or severe anemia Alterations in fetal circulation with compression of umbilical cord Reduction in blood flow to intervillous space in placenta Mosby items and derived items © 2006 by Mosby, Inc. 5 of 30 Chapter 17: Fetal Assessment during Labor Basis for Monitoring Fetal well-being during labor measured by response of FHR to UCs Reassuring FHR patterns are: Baseline FHR in normal range of 110 to 160 beats/min, with no periodic changes and a moderate baseline variability Accelerations with fetal movement Mosby items and derived items © 2006 by Mosby, Inc. 6 of 30 Chapter 17: Fetal Assessment during Labor Basis for Monitoring Fetal compromise Goals of intrapartum FHR monitoring are to identify nonreassuring patterns indicative of fetal compromise Nonreassuring FHR patterns associated with: • Fetal hypoxemia, deficiency of oxygen in arterial blood Mosby items and derived items © 2006 by Mosby, Inc. 7 of 30 Chapter 17: Fetal Assessment during Labor Basis for Monitoring Fetal compromise (cont’d) Hypoxemia can deteriorate to severe fetal hypoxia • Inadequate supply of oxygen at cellular level Nurse’s role is to assess that FHR pattern reflects adequate fetal oxygenation Mosby items and derived items © 2006 by Mosby, Inc. 8 of 30 Chapter 17: Fetal Assessment during Labor Basis for Monitoring Fetal compromise (cont’d) When pattern is nonreassuring, nurse must discriminate between: • Patterns indicating mild fetal hypoxemia • Patterns indicating severe fetal hypoxia Mosby items and derived items © 2006 by Mosby, Inc. 9 of 30 Chapter 17: Fetal Assessment during Labor Monitoring Techniques Intermittent auscultation (IA) Listening to fetal heart sounds at periodic intervals to assess FHR IA can be performed with: • Leff scope • DeLee-Hillis fetoscope • Ultrasound device Mosby items and derived items © 2006 by Mosby, Inc. 10 of 30 Chapter 17: Fetal Assessment during Labor Monitoring Techniques Electronic fetal monitoring External monitoring • FHR—ultrasound transducer • UCs—tocotransducer Internal monitoring (invasive) • Spiral electrode Mosby items and derived items © 2006 by Mosby, Inc. 11 of 30 Chapter 17: Fetal Assessment during Labor Fetal Heart Rate Patterns Baseline fetal heart rate Baseline rate is average during 10-minute segment, excluding: • Periodic or episodic changes • Periods of marked variability • Segments of baseline that differ by more than 25 beats/min • Normal range at term 110 to 160 beats/min Mosby items and derived items © 2006 by Mosby, Inc. 12 of 30 Chapter 17: Fetal Assessment during Labor Display of Fetal Heart Rate and Uterine Activity on Monitor Paper A. External mode with ultrasound and tocotransducer as signal source B. Internal mode with spiral electrode and intrauterine catheter as signal source. Frequency of contractions is measured from the beginning of one contraction to the beginning of the next B Mosby items and derived items © 2006 by Mosby, Inc. 13 of 30 Chapter 17: Fetal Assessment during Labor Fetal Heart Rate Variability A. Absent or undetected B. Minimal C. Moderate D. Marked Mosby items and derived items © 2006 by Mosby, Inc. 14 of 30 Chapter 17: Fetal Assessment during Labor Fetal Heart Rate Patterns Baseline fetal heart rate (cont’d) Variability Tachycardia: baseline more than 160 beats/min for duration of 10 minutes or longer Bradycardia: baseline less than 110 beats/min for duration of 10 minutes or longer Mosby items and derived items © 2006 by Mosby, Inc. 15 of 30 Chapter 17: Fetal Assessment during Labor Fetal Heart Rate Patterns Changes in fetal heart rate Periodic occur with UCs Episodic (nonperiodic) not associated with UCs Accelerations Decelerations • Early decelerations: response to fetal head compression • Late decelerations due to uteroplacental insufficiency Mosby items and derived items © 2006 by Mosby, Inc. 16 of 30 Chapter 17: Fetal Assessment during Labor A. Acceleration of fetal heart rate (FHR) with uterine contractions B. Spontaneous (episodic) acceleration of FHR movement A B Mosby items and derived items © 2006 by Mosby, Inc. 17 of 30 Chapter 17: Fetal Assessment during Labor Deceleration Patterns A. Early decelerations caused by head compression B. Late decelerations caused by uteroplacental insufficiency C. Variable decelerations caused by cord compression Mosby items and derived items © 2006 by Mosby, Inc. 18 of 30 Chapter 17: Fetal Assessment during Labor Fetal Heart Rate Patterns Changes in fetal heart rate (cont’d) Variable decelerations: due to umbilical cord compression Prolonged decelerations Mosby items and derived items © 2006 by Mosby, Inc. 19 of 30 Chapter 17: Fetal Assessment during Labor Care Management Assessment Nursing diagnoses Expected outcomes of care Plan of care and implementation Electronic fetal monitoring pattern recognition • Nursing management of nonreassuring patterns Mosby items and derived items © 2006 by Mosby, Inc. 20 of 30 Chapter 17: Fetal Assessment during Labor Care Management Additional methods of assessment and intervention Fetal heart rate response to stimulation Fetal oxygen saturation monitoring • Fetal pulse oximetry (FPO) Fetal scalp blood sampling Amnioinfusion Tocolytic therapy Umbilical cord acid-base determination Mosby items and derived items © 2006 by Mosby, Inc. 21 of 30 Chapter 17: Fetal Assessment during Labor Care Management Additional methods of assessment and intervention (cont’d) Patient and family teaching • Maternal positioning • Discouraging the Valsalva maneuver Documentation Evaluation Mosby items and derived items © 2006 by Mosby, Inc. 22 of 30 Chapter 17: Fetal Assessment during Labor Key Points Fetal well-being during labor is gauged by response of FHR to UCs FHR characteristics include baseline FHR and periodic changes in FHR Monitoring of fetal well-being includes: FHR assessment Watching for meconium-stained amniotic fluid Assessment of maternal vital signs and uterine activity Mosby items and derived items © 2006 by Mosby, Inc. 23 of 30 Chapter 17: Fetal Assessment during Labor Key Points Responsibility of nurse to: Assess FHR patterns Implement independent nursing interventions Report nonreassuring patterns to physician or nurse-midwife Mosby items and derived items © 2006 by Mosby, Inc. 24 of 30