Upload
janet
View
93
Download
2
Tags:
Embed Size (px)
DESCRIPTION
Basic Fetal Monitoring. Southwest Washington Perinatal Education Consortium. Kathleen Murray, CNM, MN, RN. Objectives. Identify the components of a fetal heart rate pattern: baseline, variability, accelerations, decelerations, periodic, and non-periodic changes - PowerPoint PPT Presentation
Citation preview
Basic Fetal Monitoring
Southwest Washington Perinatal Education Consortium
Kathleen Murray, CNM, MN, RN
Objectives
• Identify the components of a fetal heart rate pattern: baseline, variability, accelerations, decelerations, periodic, and non-periodic changes
• Discuss maternal and fetal physiology and how it influences fetal heart rate patterns
• Differentiate criteria for reassuring and non-reassuring fetal heart rate patterns
Fetal Heart Rate Monitoring Techniques
• Auscultation
• Fetoscope
Auscultation
• Fetoscope Low tech Need quiet room
Auscultation
• Doppler
Motion detector Portable Some models are
made for underwater use (in tub)
Doppler
Doppler used throughout pregnancy and labor
Auscultation Benefits
• Detects baseline• FHR rhythm and dysrhythmias• Hear changes in fetal heart rate• Differentiates maternal from fetal heart rate
Auscultation Limitations
• Not continuous• No printout or computer record• Can’t demonstrate variability• Requires some 1:1 nurse-time• May be limited by position of mother
Fetal Heart Rate Monitoring Techniques
• Electronic Fetal Monitoring
External Internal
Fetal Monitoring Strip
What’s the Purpose
of Fetal Monitoring???
Purpose of Electronic Fetal Monitoring
• Identify reassuring signs of fetal well-being• Screen for non-reassuring signs of a fetus
who is at risk
Benefits of External Fetal Monitoring (EFM)
• Noninvasive• Paper document• Demonstrates variability• Less labor intensive
Limitations of EFM
• Restricts patient movement• Measures cardiac motion, is not ECG• Doubling or half-count of FHR possible• Might pick up maternal HR instead
Internal Fetal Monitoring
• Spiral electrode (FSE) provides direct ECG• Measures interval between R waves • Produces very accurate picture of FHR
Benefits of Internal Monitoring (Using FSE)
• Accurate measure of FHR and variability• May detect dysrhythmias• Can allow for more patient movement
Limitations of FSE
• Membranes must be ruptured to use• Risk of infection• If fetus has died, may pick up maternal
heart rate accidentally
Uterine Activity Monitoring
• External: tocotransducer• Detects frequency and length, not strength• Requires palpation to assess strength of
contractions
Uterine Monitoring
• Note the normal-looking UC first
• Then baseline rises and next few UC’s seem high (false)
• External UC monitor does not accurately show strength
External Uterine Monitoring
• BENEFITS• Noninvasive• Provides
documentation of UC frequency and duration
• LIMITATIONS• Does not measure
strength of contraction, nor resting tone of uterus
• Difficult to use in maternal obesity, in some positions
Monitoring With Internal Uterine Pressure Catheter (IUPC)
• Accurate measure of uterine pressure• Contraction strength, and resting tone• Measured in mmHg• Accurate timing of FHR changes in relation
to UC’s
IUPC
• INDICATIONS• External reading not
adequate• Labor dystocia• Fetal distress• Amnioinfusion for
cord compression
• RISKS• Infection• Uterine perforation• Placental injury• Extraovular placement
IUPC placement
Are You Worried?
Fetal Heart Rate Monitoring• Baseline, rounded up to nearest 5 bpm• Variability• Accels and Decels• Periodic changes (with UC’s)• Non-periodic changes (spontaneous)
Fetal Heart Rate Monitoring
• Baseline• Normal: 110-160 bpm• Tachycardia : >160 bpm for >10 minutes• Bradycardia: <110 bpm for >10 minutes
Variability
• Characteristic of FHR baseline• Smoothness, or roughness of the line• Very important characteristic of FHR, must
be present for reassuring strip
Variability
• Assessed in between UC’s and periodic changes
• Absent: undetectable• Minimal: 1-5 bpm amplitude• Moderate: 6-25 bpm (normal) • Marked: >25 bpm (also called saltatory)
Causes of Decreased Variability
• Non hypoxic causes• Fetal sleep (20 min)• Medications• Tachycardia (such as
from maternal fever)• Fetal anomaly• dysrhythmia
• Hypoxic causes• Uteroplacental
insufficiency• Cord compression• Mat. Hypotension• Tachysystole• Abruption• Tachycardia
Interventions
• Determine cause• Position change• IV fluids• Oxygen 10 liters snug face mask• Stop or turn down pitocin• Place internal FSE• Notify MD/CNM without delay
Sinusoidal Pattern
• Not to be confused with variability!!• Regular, sine-like wave pattern with amplitude of
5-15 bpm above and below baseline• Ominous in most cases, requires prompt
intervention, usually immediate C-section• Usually caused by severe fetal anemia, can be
from hypoxia, or briefly from narcotic dose
Causes of Increased Variability
• Uteroplacental insufficiency or• Cord Compression or• Fetal Activity and• A compensatory response to a mild hypoxic
event
Interventions
• Determine cause• Position change• Assess fetal response
Accelerations
• Caused by sympathetic nervous system response to fetal movement or stimuli, normal and reassuring, rules out acidosis
• But, periodic accels, with UC’s are mild cord compression
Criteria for Accelerations
• <32 weeks gestation, stays 10 beats above baseline for at least 10 seconds
• For > 32 weeks, acceleration stays 15 beats above baseline for at least 15 seconds
Early Decelerations
• Caused by pressure on fetal head, vagal response
• Uniform, mirrors contraction• Gradual onset, reaches nadir >30 sec.• Reaches nadir at peak of UC, returns to
baseline by the end of UC• Benign
Variable Decelerations
• Caused by cord compression, baroceptor response quickly slows FHR to compensate
• Abrupt onset, reaches nadir < 30 sec.• Decel. Of >15 bpm lasting > 15 sec., and
return to baseline < 2 minutes
Causes of Variable Decelerations
• Intrauterine• Nuchal cord, or body
entanglement• Oligohydramnios• Rupture of membranes• Short cord or true knot• Occult prolapse of
cord
• Maternal conditions• Positioning• Second stage labor
with descent• Monoamniotic
multiple gestation
Variable Decel. Characteristics
• Shape, depth, and duration vary (not uniform), can be V, W, U shaped
• Timing may vary• Watch for fetal compromise• increasing baseline• loss of variability• slow return to baseline
Interventions
• Vag. Exam rule out prolapse
• Position change• IV fluids• Oxygen 10 l/mask• Turn pit off or down• Assess fetal response• Call MD/CNM
• Same list as with late decels, except added vag exam, and
• If ordered, start amnioinfusion
Late Decelerations
• Caused by uteroplacental insufficiency• Fetus runs low on oxygen during a UC• Maternal, placental, or fetal cause of
inadequate oxygen to fetal heart• Often indicates metabolic acidosis• Needs urgent response
Late Decel. Characteristics
• Always associated with a UC, with delay in timing
• Gradual decrease from baseline to nadir >30 seconds
• Nadir occurs after peak of UC• Depth of decel usually only 5-30 bpm
Interventions
• Lateral position, (usually left works best)
• Increase IV fluids• Oxygen 10 l/mask• Stop pitocin• Call MD/CNM
• Determine cause, and correct if possible
• Assess fetal response• Prepare for possible
delivery
Prolonged deceleration
• Deceleration of >15bpm, lasting more than 2 minutes, less than 10 minutes
• Measured from onset until return to baseline• Often is long, exaggerated variable• Cause often: cord compression, or tachysystole, or maternal hypotension
Interventions
Without Looking at Your Notes, Tell Me What You’d Do for a Prolonged
Decel?Hint: Same List As for lates
Interventions
• Lateral position• Increase IV fluids• Oxygen 10 l/mask• Stop pitocin• Call MD/CNM
• Determine cause, and correct
• Assess fetal response• Prepare for possible
delivery, moving into O.R. by 3rd minute if not resolving
Uterine Contractions
Contraction Monitoring
• Interval “how far apart are they?”• Duration “how long do they last?”• Resting tone: how does the uterus feel between
contractions• Intensity “how hard are they?” mild moderate strong
Electronic Fetal Monitoring
Strip Interpretation
Systematic Review of strip
• Baseline Normal is ___________• Variability Expressed as _________• AccelerationsPresent, or absent
• DecelerationsPresent, or absent3 major types:________________________________________________• Contraction pattern
Begin….
• By looking at what is reassuring on the strip
• Then, note any concerning features
Documentation
• Critical job for you, your hospital, the patient
• Chart as if the hard copy of your strip will get lost later…10% or more of all strips do
• Clear, concise language• Institution-specific• Standards of care
Documentation on the strip
• Label/write patient name, date etc.• Events, actions, nursing interventions• Calls to MD, CNM, nursery, etc.• What not to write on strip
Auscultation documentation
• Rate• Rhythm (regular, irregular)• Increases in rate (audible accels)• Decreases (audible decels, and the timing)
FHR Documentation Intervals
Auscultation or EFM• Low risk patient: Active labor every 30 minutes 2nd stage every 15 minutes• High risk patient Active labor every 15 minutes 2nd stage every 5 minutes
If Confusing Pattern
• Complex patterns, combination of 2 types of decelerations sometimes exist
• Focus on: baseline stable or not, variability and accels, whether decels are periodic or not, timing related to UC’s, abruptness of change from baseline
• Sometimes helps to draw decel in your chart notes
Documenting Uterine Activity
• What four characteristics do you note?• ____________________• ____________________• ____________________• ____________________
Example of Charting
2100-FHR baseline 130, accels to 160 present, no decels. UC’s q 2.5 minutes x 60-80 seconds, palpate moderate, resting tone soft. K Jones, RN
Non-reassuring FHR Patterns
• Document the following: Pattern Nursing intervention Evaluation of response Notification of MD or CNM
Example of Charting
• 2120- FHR 170, minimal variability, no accels, no decels. UC’s q 2.5-3 minutes x 80-130 seconds, peaks 40-50mmHg, resting tone 25.
• Positioned Left-lateral, O2 on 10 l per tight mask, pitocin turned off, IV rate increased. No change in FHR pattern. Phoned Dr James with report of non-reassuring strip and asked him to come now to evaluate. He stated he is on his way. Explained to patient and husband. K Jones, RN
Conclusion
• Methods of fetal monitoring• Components of FHR, and uterine activity• Causes of various changes• Nursing interventions• Systematic review of strip• Documentation
References
Abcdefm:electronic fetal monitoring , Curran, Carol, and Torgersen, Keiko, Colley Avenue Copies & Graphics, Virginia Beach, VA, 2006, pp.31,158-9, 167,169,170,178-9.
Fetal Heart Monitoring Principles & Practices 4th ed., Lyndon, Audrey et al editors, AWHONN, Kendall/Hunt, Dubuque, Iowa, 2003.
NCC Monograph, Vol 2, No. 1, 2006, National Certification Corporation, pages 6-11.