OB NURS 306 OB Final Study Guide

Chapter 3 Genetics, Conception, Fetal Development, and Reproductive Technology ! Genetics " study of heredity ! Genomics " addresses all genes and their interrelationships in order to identify their combined influence on growth and development of the organism o Providing better methods for preventing disease and abnormalities, diagnosing diseases, predicting health risks, personalizing treatment plans ! 30,000 genes in the human genome (organism’s complete set of DNA) ! 46 chromosomes; 22 homologous pairs of chromosomes and one pair of sex chromosomes ! genotype " person’s genetic makeup ! phenotype " how genes are outwardly expressed (eye color, hair color, height) ! recessive genetic disorders " sickle cell anemia, cystic fibrosis, thalassemia, Tay-Sachs disease ! carrier testing " identify individuals who carry one copy of a gene mutation that, when present in two copies causes a genetic disorder; used when there is a family history of genetic disorder ! preimplantation testing/preimplantation genetic diagnosis " used to detect genetic changes in embryos that are created using assisted reproductive techniques ! prenatal testing " early detection of genetic disorders ! risks for conceiving child with genetic disorder " maternal age older than 35, man/woman who has genetic disorder; family history of genetic disorder, history of previous pregnancy resulting in a genetic disorder or newborn abnormalities ! refer to support group whether they wish to terminate/continue with pregnancy ! sickle cell anemia o most common of African ancestry o sickle-cell hemoglobin forms rigid crystals that distort and disrupt RBCs; oxygen-carrying capacity of blood is diminished ! cystic fibrosis o most common genetic disease of European ancestry o production of thick mucus clogs in bronchial tree and pancreatic ducts o most severe effects are chronic respiratory infections and pulmonary failure ! Tay-Sach disease o Most common among Jewish ancestry o Degeneration of neurons and nervous system results in death by the 2 years old ! PKU o Lack of enzyme to metabolize the amino acid phenylalanine " leads to severe mental and physical retardation o Effects may be prevented by use of a diet at beginning of birth that limits phenylalanine ! Huntington’s Disease o Uncontrollable muscle contractions between 30-50 years followed by memory loss and personality o No treatment that can delay mental deterioration ! Hemophilia (X-linked) o Lack of factor 8 o Can be controlled with factor 8 from donated blood ! Duchenne’s Musclular Dystrophy o Replacement of muscle by adipose or scare tissue with progressive loss of muscle function; often fatal before age 20 due to involvement of cardiac muscle ! teratogens " any drugs, viruses, infections, or other exposures that can cause embryonic/fetal developmental abnormality ! degree or types of malformation vary on length of exposure, amount of exposure, and when it occurs during human development ! developing human is most vulnerable to effects of teratogens within first 8 weeks of gestation (organogenesis)" can cause gross structural defects ! exposure after 13 weeks may cause fetal growth restriction or reduction of organ size ! toxoplasma is a protozoan parasite found in cat feces and uncooked/rare beef and lamb o can cause fetal demise, mental retardation, blindness when fetus is exposed o avoid contact with cat feces and eating rare beef or lamb if pregnant or attempting pregnancy ! rubella " increased risk for heart defects, deafness and/or blindness, mental retardation, fetal demise ! cytomegalovirus " increased risk for hydrocephaly, microcephaly, cerebral calcification, mental retardation, hearing loss ! herpes varicella/chicken pox " increased risk for hypoplasia of hands and feet, blindness/cataracts, mental retardation ! syphilis " increased risk for skin, bone and/or teeth defects, fetal demise ! cocaine " increased risk for heart, limbs, face, GI/GU tract defects, cerebral infarctions, placental abnormalities Chapter 4 Physiological Aspects of Antepartum Care ! 2! ! G/P System o Gravida: # times a woman has been pregnancy including current pregnancy o Para: # of births after 20 weeks’ gestation whether live or stillbirths o Abortions are not accounted for in this system ! GTPAL o G: # times pregnancy o T: # of term infants born after 37 weeks o P: # of preterm infants between 20 and 37 weeks o A: # of abortions either spontaneous or induced before 20 weeks o L: # of living children ! Nulligravida: woman who has never been pregnant or given birth ! Primigravida: woman who is pregnant for the first time ! Multigravida: someone who is pregnant for at least the second time ! Prenatal period " entire time period during which a woman is pregnant through birth of baby ! Nurse places emphasis on health education and health promotion ! Family-centered maternity care is a model of obstetrical care based on a view of pregnancy and childbirth as a normal life event, a life transition that is not primarily medical but rather developmental ! Low-risk population should have approximately 14-16 prenatal visits per pregnancy ! First trimester o Woman learns frequency of follow-up visits and what to expect from pregnancy visits as pregnancy progresses during initial visit o Comprehensive health and risk assessment; currently pregnancy history; complete physical and pelvic examination; nutrition assessment; psychosocial assessment; assessment for intimate partner violence o Fetal heart tones are auscultated with US Doppler, initially by 10 and 12 weeks o At end of first trimester, fetus is 3 inches in length and weights 1-2 ounces, all organ systems are present o Assessment of uterine growth after 10-12 weeks is measured by height of fundus with centimeter measuring tape; zero point of tape is placed on the symphysis pubis and tape is extended to top of fundus; MEASUREMENT SHOULD EQUAL # OF WEEKS PREGNANT o Certain types of fish (king mackerel, shark, swordfish, tilefish) should be avoided due to high levels of methylmercury ! Second trimester o Chart review; interval history; focused physical assessment; pelvic exam/sterile vaginal exam if indicated; confirm EDD o Triple/quad screen (neural tube defect); US; screening for gestational diabetes; hemoglobin and hematocrit; antibody screen if Rh-negative (Administration of RhoGAM if Rh-negative and anti-body screen negative) # Administered prophylactically at 28 weeks to prevent isoimmunization from potential exposure to Rhpositive fetal blood during normal course of pregnancy # Adverse reaction " pain at IM site; fever o Slight decrease in blood pressure toward end of second trimester o Assess for quickening " when the woman feels baby move for first time o Leopold’s maneuvers to identify position of fetus o Slight lower body edema is normal due to decreased venous return o At 20 weeks, fetus is 8 inches long and weights 1 pound o Increase in calorie intake by 340 kcal/day ! Third trimester o Chart review; interval history; nutrition follow-up; focused physical assessment; pelvic exam/sterile vaginal exam if indicated o Group B Strept at 35-37 weeks; H&H if not done in second trimester; repeat GC, chlamydia, RPR, HIV HbSAg; 1- hour glucose challenge test at 24-28 weeks o Record fetal movement count " 10 distinct fetal movements within 2 hours is considered reassuring OR 4 movements in 1 hour o At term, fetus is 17-20 inches long, 6-8 pounds o Increase in calorie intake by 452 kcal/day Chapter 6 Antepartal Tests ! Chorionic villus sampling " aspiration of a small amount of placental tissue for chromosomal, metabolic, or DNA testing o Between 10 and 12 weeks to detect fetal abnormalities caused by genetic disorders o Tests for cystic fibrosis but not neural tube defects o Supine position for transabdominal aspiration with US to guide placement o Lithotomy for transvaginal aspiration with US to guide placement o Small biopsy of chorionic (placental) tissue is removed o Assess fetal and maternal well-being post-procedure; FHR is auscultated twice in 30 minutes ! 3! o Instruct woman to report abdominal pain/cramps, leaking of fluid, bleeding, fever, chills o Results within 1 week ! Amniocentesis o Needle is inserted through maternal abdominal wall into uterine cavity to obtain amniotic fluid o Genetic testing, fetal lung maturity, assessment of hemolytic disease in fetus or for intrauterine disease # Fetal lung maturity, monitor for L/S RATIO, PG, LBC o Usually performed 14-20 weeks gestation o Results within 2 weeks o FULL BLADDER MAY BE REQUIRED FOR ULTRASOUND VISULIZATION IF WOMAN IS LESS THAN 20 WEEKS ! Delta OD 450 o Evaluation of amniotic fluid obtained via amniocentesis to predict life-threatening anemia in fetus during second and third trimester o Used in a lab to determine if there is a deviation of optical density at 45 nm ! Fetal blood sampling/percutaneous umbilical blood sampling (CORDOCENTESIS) o Removal of fetal blood from umbilical cord " used to test for metabolic and hematological disorders, fetal infection, fetal karyotyping o may be done as early as 11 weeks but usually done in second trimester o results within 48 hours o POSITION WOMAN IN LATERAL/WEDGED POSITION TO AVOID SUPINE HYPOTENSION DURING FETAL MONITORING TESTS o Have terbutaline ready as ordered in case uterine contractions occur during procedure o Assess fetal well-being post-procedure 1-2 hours via external fetal monitoring ! Alpha-fetoprotein (AFP) o Done at 15-20 weeks gestation o Assessed in maternal blood to screen for certain developmental defects in the fetus (NTD, ventral abdominal wall defects) o Increased levels associated with NTDs, anencephaly, omphalocele, gastroschisis o Decreased levels associated with Down syndrome o Abnormal findings require additional testing " amniocentesis, VNS, US ! Multiple marker screen o Combination of AFP, human chorionic gonadotropin (hCG), estriol levels o Detects for some trisomies and NTDs o done at 15-16 weeks gestation o maternal blood is drawn and sent to lab o low levels of maternal serum alpha-fetoprotein and unconjugated estriol levels suggest an abnormality o hCG and inhibin-A levels are twice as high in pregnancies with trisomy 21 (Down’s Syndrome) o decreased estriol levels are an indicator of NTDs ! Daily fetal movement o Proposed as primary method of fetal surveillance after 28 weeks gestation o Instruct woman to palpate abdomen and track fetal movements daily for 1-2 hours o 10 distinct fetal movements within 2 hours is normal # once movement is achieved, counts can be d/c for the day o 4 movements in 1 hour is reassuring # if decreased, have woman eat, rest and focus on fetal movement for 1 hour o FEWER THAN 4 FETAL MOVEMENTS IN 2 HOURS SHOULD BE REPORTED o LIE ON SIDE WHILE COUNTING MOVEMENTS ! Non-stress test o Uses electronic fetal monitoring to assess fetal condition/well-being o Looking for accelerations; baby is nice and active o Used in women with complications such as HTN, diabetes, multiple gestation, trauma and/or bleeding, woman’s report of lack of fetal movement, placental abnormalities o Heart rate of normal fetus with adequate oxygenation and intact autonomic nervous system accelerates in response to movement o Monitored with external FHR until reactive (up to 40 minutes) while running FHR contraction strip for interpretation o Considered reactive when FHR increases 15 beats above baseline for 15 seconds twice or more in 20 minutes o In fetuses less than 32 weeks, two accelerations peaking at least 10 bpm above baseline and lasting 10 seconds in a 20-minute period is reactive o Nonreactive NST is one without sufficient FHR accelerations in 40 minutes " followed up for further testing ! 4! o Presence of repetitive variable decelerations that are >30 seconds requires further assessment of amniotic fluid o VOID AND LIE IN A SEMI-FOWLER’S/LATERAL POSITION ! Vibroacoustic stimulation o Uses auditory stimulation to assess fetal well-being with EFM when NST is nonreactive # Used to elicit a change in fetal behavior, fetal startle movements, increased FHR variability o Used only when baseline rate is determined to be within normal limits o Conducted by activating an artificial larynx on the maternal abdomen near the fetal head for 1 second in conjunction with NST; can be repeated at 1-minute intervals up to 3 times o Reactive if FHR increases 15 beats above baseline for 15 seconds twice in 20 minutes ! Contraction stress test o Assess fetal well-being and uteroplacental function with EFM in women with nonreactive NST at term gestation o Identify a fetus that is at risk for compromise through observation of the fetal response to intermittent reduction in utero placental blood flow associated with stimulated uterine contractions o Monitor FHR and fetal activity for 20 minutes o If no spontaneous UCs, initiate contractions by having woman brush nipples for 10 minutes # Unsuccessful " oxytocin via IV until 3 UCs in 10-20 minutes lasting 40 seconds o Negative or normal when there are no significant variable decelerations or no late decelerations in a 10 minute strip with 3 UCs > 40 seconds assessed with moderate variability o Positive if late decelerations of FHR with 50% of UCs usually assessed with minimal or absent variability o Equivocal or suspicious when there are intermittent late or variable decelerations o POSITION IN SEMI-FOWLER’S POSITION ! Amniotic fluid index o Measures volume or amniotic fluid with ultrasound to assess fetal well-being and how well the placenta is working o Amniotic fluid based on fetal urine production o Average measurement " 8-24 cm o AFI less than or equal to 5 cm is indicative of oligohydramnios # Associated with prenatal mortality o AFI above 24 cm is indicative of polyhydramnios # May indicate fetal malformation " NTDs, obstruction of fetal GI tract, fetal hydrops ! Biophysical profile o NST with additional 30 minutes of ultrasound observation of fetal breathing movement, gross body movement, fetal tone, amniotic fluid volume, heart rate reactivity o One or more episodes of rhythmic breathing movements of 30 seconds or movement within 30 minutes is expected o Three or more discrete body/limb movements within 30 minutes are expected o One or more fetal extremity extension with return to fetal flexion or opening and closing of hand is expected o Pocket of amniotic fluid that measures at least 2 cm in 2 planes perpendicular to each other is expected o Score of 2 is assigned to each component # 8/10 is reassuring # 6/10 is equivocal and may indicate need for delivery depending on gestational age # 4/10 delivery is recommended because of a strong correlation with chronic asphyxia # 2/10 or less prompts immediate delivery ! modified biophysical profile o combines NST as an indicator of short term fetal well-being and AFI as indicator of long-term placental function o considered normal when NST is reactive and AFI is greater than 5cm Chapter 8 Intrapartum Assessment and Interventions ! true labor o occur at regular intervals and increase in frequency, duration and intensity o bring about changes in cervical effacement and dilation ! false labor o irregular contractions with little or no cervical changes ! spontaneous rupture of the membranes can occur before onset of labor but typically occurs during labor o woman should deliver within 24 hours to reduce risk of infection ! confirmation of rupture of membranes (ROM) o speculum exam to asses for fluid in the vaginal vault o Nitrazine paper " paper turns blue when in contact with amniotic fluid o Ferning " ferning pattern confirms ROM o AmniSure testing kit ! INCREASED RISK OF UMBILICAL CORD PROLAPSE WITH ROM ! Normal amniotic fluid is clear/cloudy with normal odor (similar to ocean water or loam of a forest floor) ! 5! Stages of labor and childbirth ! Labor/parturition is the process in which the fetus, placenta and membranes are expelled ! First stage " begins with onset of labor and ends with complete cervical dilation o Longest stage, typically lasting 12 hours for primigravidas and 8 hours for multigravidas o Latent " 0-3 cm; 0%-40% effacement; contractions lasting 30-45 seconds and mild intensity # Strong menstrual cramps # Average length of 9 hours for primiparous and 5 hours for multiparous # Many are talkative and able to relax with contractions # Order CBC, UA, possible drug screening; start IV/insert saline lock # Intrapartum GBS prophylaxis # Walking " important in facilitating labor progression and fetal descent and rotation and in making UCs more efficient o Active " 4-7 cm; 40%-80% effacement; contractions every 2-5 min with duration 45-60 seconds # Cervix dilates 0.5 cm/hr for primiparous and 1.5 cm for multiparous # Averages 3-6 hours; typically shorter for multigravidas # Woman may have decreased energy and experience fatigue # Women usually come to birthing center at this time # Rupture membranes if not previously ruptured # Perform internal monitoring with internal fetal electrode # Order pain medication or epidural anesthesia # Monitor v/s every 2 hours; every 1 hour if ROM o Transition " 8-10 cm with complete effacement; intense contractions every 1-2 minutes lasting 60-90 seconds # Typically the most difficult but shortest # Assess FHR and UCs every 15 minutes # Provide calming support and reassurance ! Second stage " begins with complete dilation of cervix and ends with delivery of baby o Typically lasts 50 minutes for primigravidas and 20 minutes for multigravidas; although several hours is normal o May have intense urge to push or bear down when baby reaches pelvic floor o Contractions are intense occurring every 2 minutes and lasting 60-90 seconds o Ferguson’s reflex = urge to bear down o open glottis refers to spontaneous, involuntary bearing down accompanying the forces of the uterine contraction and is usually characterized by expiratory grunting or vocalizations o benefits of upright position (head of bed at 45 degrees) " pelvic diameter may be increased by 30%, shortened duration of the second stage, pain may be decreased, perineal trauma may be decreased o delayed pushing " laboring down/passive pushing/rest and descent " may be appropriate for women with epidural anesthesia who do not feel the urge to push o perform episiotomy if necessary " incision in the perineum to provide more space for presenting part at delivery # mediateral episiotomy is cut at 45 degree angle to left/right; used in large infants; heals more slowly, causes greater blood loss and more painful o first-degree laceration -- > involves perineal skin and vaginal mucous membrane o second-degree laceration " involves skin, mucous membrane, fascia of perineal body o third-degree laceration " involves skin, mucous membrane, muscle of the perineal body and extends to rectal sphincter o fourth-degree laceration " extends into rectal mucosa and exposes the lumen of rectum o monitor FHR every 5-15 minutes or after each contraction o encourage rest between contractions by breathing wit patient/therapeutic touch ! Third stage " begins with delivery of baby and ends with delivery of placenta o Placenta usually separates within a few minutes after delivery, but continues to contract until expelled which can take 5-30 minutes o Signs of impending delivery of placenta # Upward rising of the uterus into a ball shape; lengthening of the umbilical cord at the introitus; sudden gush of blood from the vagina; active management of placental delivery consists of the use of uterotonics, controlled cord traction, uterine massage o Assess maternal v/s every 15 minutes o Uterotonics # Oxytocin (Pitocin) • Stimulates uterine smooth muscle that produces intermittent contractions # Mehtylergonovine (Methergine) • Directly stimulates smooth and vascular smooth muscles causing sustaining uterine contractions # Carboprost (Hemabate) • Contraction of uterine muscle # Misoprostol (Cytotec) ! 6! • Acts as a prostaglandin analogue causes uterine contractions ! Fourth stage (immediate postpartum period) " begins after delivery of placenta and completed 4 hours later o Primary mechanism by which hemostasis is achieved at the placental site is vasoconstriction produced by a wellcontracted myometrium o This stage also begins the postpartum period o Assess uterus/lochia; administer medications as order; assess maternal v/s every 15 minutes; monitor newborn every 30 minutes o IMPORTANT GOAL IS NEWBORN-FAMILY ATTACHMENT o BEST TIME TO INSTITUTE BREASTFEEDING Sign 0 1 2 Respiratory effort Absent Slow, irregular Good cry Heart rate Absent Slow, below 100 bpm Above100 bpm Muscle tone Flaccid Some flexion of ext. Active motion Reflex activity None Grimace Vigorous cry color Pale, blue Body pink, blue ext. Completely pink ! Apgar scores should be obtained at 1 minute and 5 minutes after birth ! If five 5 minute Apgar score is less than 7, additional scores should be assigned every 5 minutes up to 20 minutes ! Should be recorded every 30 minutes until newborn’s condition is stable for at least 2 hours ! 7-10 indicates stable status ! initial steps of newborn resuscitation " provide warmth by placing baby under radiant heat source, positioning the head in a “sniffing” position to open the airway, clearing the airway if necessary with bulb syringe/suction catheter, drying baby, stimulating breathing ! erythromycin ointment is administered to the eyes as prophylaxis to prevent gonococcal and Chlamydia infections ! vitamin K is administered via IM injection to prevent hemorrhagic disease caused by vitamin K deficiency ! hepatitis B virus vaccine is recommended for all newborns Chapter 9 Fetal Heart Rate Assessment Terminology related to fetal heart rate assessment ! baseline FHR " mean FHR rounded to increments of 5 bpm during a 10-minute window, excluding accelerations and decelerations ! baseline variability " fluctuations in the baseline FHR that are irregular in amplitude and frequency. Fluctuations are visually quantified as the amplitude of the peak to trough in bpm. Determined in a 10-minute window, excluding accelerations and decelerations. Reflects the interaction between the fetal sympathetic and parasympathetic nervous system. o Absent " amplitude range is undetectable o Minimal " amplitude range is visually undetectable ≤ to 5 bpm o Moderate " amplitude from peak to trough 6 bpm to 25 bpm o Marked " amplitude range > 25 bpm ! Accelerations " visually apparent, abrupt increase in FHR above the baseline. The peak of the acceleration is ≥ 15 bpm over the baseline FHR for ≥!15 seconds and > 2 minutes. o Before 32 weeks gestation acceleration is ≥ 10 beats over the baseline FHR for ≥ 10 seconds. o Prolonged accelerations are ≥ 2 minutes, but ≤ 10 minutes ! deceleration " transitory decrease in the FHR from the baseline o early deceleration " visually apparent gradual decrease in FHR below baseline. The nadir (lowest point) of the deceleration occurs at the same time as the peak of the UC. In most cases the onset, nadir, and recovery of the deceleration are coincident or mirror the contraction. o variable deceleration " visually apparent abrupt decrease in the FHR below baseline; decrease in FHR is ≥ 15 bpm lasting ≥!15 seconds and < 2 minutes in duration o late deceleration " visually apparent gradual decrease of FHR below the baseline. Nadir (lowest point) of the deceleration occurs after the peak of the contraction. In most cases the onset, nadir, and recovery of the deceleration usually occurs after the respective onset peak, and end of UC. o prolonged deceleration " visually apparent abrupt decrease in FHR below baseline that is ≥ 15 bpm lasting ≥ 2 minutes but ≤ 10 minutes o sinusoidal pattern " having a visually apparent smooth sine-like wave like undulating pattern in FHR baseline with a cycle frequency of 3-5/min that persists for ≥ to 20 minutes ! tachycardia " baseline FHR of > 160 bpm lasting 10 minutes or longer ! bradycardia " baseline FHR of <110 bpm lasting for 10 minutes or longer ! normal FHR " FHR pattern that reflects a favorable physiological response to the maternal fetal environment ! abnormal FHR " FHR pattern that reflects an unfavorable physiological response to the maternal fetal environment Modes or types of fetal and uterine monitoring ! 7! ! auscultation o use of fetoscope/Doppler to hear the FHR by externally listening without the use of a paper recorder o fetoscope " allows practitioner to hear sounds associated with opening/closing of ventricular valves via bone conduction o Doppler " uses ultrasound technology, using sound waves deflected from fetal heart movements # Converts information into a sound that represents cardiac events ! palpation of contractions o assesses for frequency, tone, duration, intensity o nurse places fingertips on the fundus of uterus and assess for degree of tension as contractions occur o intensity of contractions is measured at peak of the contraction # mild or 1+ feels like tip of nose (easily indented) # moderate or 2+ feels like chin (can slightly indent) # strong or 3+ feels like forehead (cannot indent uterus) o resting tone is measured between contractions and listed as either soft or firm uterine tone ! external electronic fetal and uterine monitoring o uses ultrasound device to detect FHR and a pressure device to assess uterine activity o external EFM detects FHR baseline, variability, accelerations, decelerations o erratic FHR recordings or gaps on paper recorder may be due to inadequate conduction of US signal displacement of transducer, fetal/maternal movement, inadequate US gel, fetal arrhythmia o contractions are measured via tocodynamometer; cannot measure pressure/intensity ! internal electronic fetal and uterine monitoring o uses fetal scalp electrode/internal scalp electrode that is applied to presenting part of fetus to detect FHR o involves using intrauterine pressure catheter (IUPC) placed in the uterine cavity to directly measure uterine contractions o MEMBRANES MUST BE RUPTURED FOR BOTH METHODS o Contraindications " chorioamnionitis, active maternal genital herpes, HIV, conditions that preclude vaginal exams o May be used due to maternal obesity or lack of progress in labor when quantitative analysis of uterine activity is needed for clinical decision making; treat worsening category II tracing o Contractions are measured via an intrauterine pressure catheter " contractions measured in mm Hg o Peak pressure " maximum uterine pressure during a contraction measured with IUPC o Resting tone/baseline pressure " uterine pressure between contractions and should be about 5-25 mm Hg ! Telemetry o Continuous electronic fetal monitoring which involves connecting patient to a radio frequency transmitter that allows patient to walk/take bath without being connected to monitor ! monitor paper used for the electronic fetal monitor o paper speed is 3 cm per minute; each dark vertical line is 1 minute and each lighter vertical line is 10 seconds o FHR on top grid; UC on lower grid FHR and contraction pattern interpretation ! Baseline fetal heart rate " assess over 10-minute period o Mean FHR rounded to increments of 5 bpm during 10-minute window excluding accelerations, decelerations, or marked variability o Normal range " 110-160 bpm o If above 200-220 bpm, fetal demise may occur o Fetal tachycardia " maternal fever, dehydration, anxiety, exposure to medications (terbutaline); may be sign of early fetal hypoxemia o Fetal bradycardia " maternal dehydration, hypotension, medications such as anesthetics, rupture of uterus/vasa previa # Sudden profound bradycardia (less than 80 bpm ) is obstetrical emergency # Fetal response related to hypoxia, umbilical cord occlusion # Assess for prolapsed cord ! Baseline variability o Fluctuations in the baseline FHR that are irregular in amplitude and frequency o Most important predictor of adequate fetal oxygenation and fetal reserve during labor o Absent – not good (flat line) o Minimal – beat to beat fluctuation of 5 beats or less o Moderate – what you want; fluctuation 6 to 25 beats per minute # Predicts well-oxygenated fetus with normal acid-base balance at the time o Marked – greater than 25 beats per minute o MINIMAL OR ABSENT CAN OCCUR WHEN FETUS IS IN A SLEEP, SEDATED BY CERTAIN NERVOUS SYSTEM DEPRESSANTS OR A CENTRAL NERVOUS SYSTEM THAT HAS BEEN PREVIOUSLY INJURED; CAN ALSO BE SIGNIFICANT FOR PRESENCE OF FETAL HYPOXIA OR ACIDOSIS ! Periodic and episodic changes