16.8: Key Terms
- Page ID
- 104696
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)- absent FHR variability
- lack of FHR baseline fluctuation
- accelerations
- abrupt increases in the FHR above the baseline 15 bpm or more lasting 15 seconds or more
- bradycardia
- FHR baseline less than 110 bpm lasting greater than 10 minutes
- contraction frequency
- how often the contractions are occurring, determined by measuring from the beginning of one contraction to the beginning of the next contraction
- contraction length
- how long the contraction lasts, determined by measuring the time between the beginning of the contraction to the end of the contraction
- contraction strength
- intensity of the contraction, determined externally by palpation or internally by the intrauterine pressure catheter
- early decelerations
- usually, symmetrical, gradual FHR declines that then return to baseline, mirroring the uterine contraction
- fetal heart rate (FHR)
- heart rate and rhythm of the fetus
- fetal reserve
- fetus’s capacity to tolerate the normal intermittent interruptions in oxygenation during labor and recover back to full oxygenation
- fetal scalp electrode (FSE)
- affixed to the scalp of the fetus and provides close monitoring of the fetal heart rate
- FHR baseline
- average beats per minute in a 10-minute segment, excluding periodic changes or marked variability
- FHR variability
- beat-to-beat fluctuations in the FHR baseline
- intermittent auscultation (IA)
- technique of assessing fetal well-being by listening to and counting the fetal heart rate for a specified amount of time and at specified intervals, depending upon the stage of labor
- intrauterine pressure catheter (IUPC)
- device placed between the uterus and fetus that measures the exact pressure inside the uterus at rest and during contractions
- intrauterine resuscitation
- specific interventions aimed at increasing oxygen to the placenta and to the umbilical cord to reverse fetal hypoxia
- late decelerations
- symmetrical, gradual decreases in FHR after the start of a uterine contraction, with return to baseline after the ending of the contraction
- marked FHR variability
- FHR baseline fluctuation greater than 25 bpm
- minimal FHR variability
- FHR fluctuations of 5 bpm or fewer
- mm Hg
- millimeters of mercury, abbreviated mm Hg; measurement unit of intrauterine pressure catheter
- moderate FHR variability
- FHR fluctuations between 6 and 25 bpm
- Montevideo unit
- unit of measurement of uterine contraction strength via IUPC
- periodic changes in the FHR
- accelerations and decelerations of the FHR, abrupt or gradual, in relation to the FHR baseline
- prolonged decelerations
- isolated, sporadic decelerations of at least 15 bpm from the FHR baseline that last 2 to 10 minutes from onset to return to baseline
- tachycardia
- FHR baseline greater than 160 bpm
- tocodynamometer
- device that detects the frequency of uterine contractions
- uterine contraction (UC)
- tightening and shortening of the uterine muscles
- uteroplacental insufficiency
- disruption of the delivery of oxygen and nutrients to the fetus from the placenta
- variable decelerations
- abrupt decelerations of the FHR of at least 15 bpm below the baseline that last at least 15 seconds and less than 2 minutes, regardless of any uterine contraction