NCC EFM Complete Study Guide

NCC EFM Complete Study Guide Causes of uteroplacental perfusion decrease: Ans- • HTN • Pregnancy • DM • Hypotension • Excessive uterine contractions (hypertonus) • Decreased surface area, edema, degenerative calcifications, infarcts, infection FHR reflects fetal oxygenation from which extrinsic factors: Ans- • Maternal oxygenation • Uterine blood flow • Placental change • Umbilical blood flow FHR reflects oxygenation from which intrinsic factors: Ans- • Fetal circulation • Oxygenation of tissues • FHR regulation Fetal shunts: Ans- • Ductus venosus- liver • PFO- Right to left atria • Ductus arteriosis- pulmonary a. to aorta Oxygen depletion cascade: Ans- • Aerobic metabolism • Hypoxemia • Tissue hypoxia • Anaerobic metabolism • Lactic acid build up • Metabolic acidosis Sympathetic innervation: Ans- • Releases Eip/norepi • Increases FHR Parasympathetic/Vagal innervation: Ans- • Releases ach • Decreases FHR and transmits variability Early decel: Ans- • Fetal head compression • -vasovagal response Variable decel: Ans- • Cord compression • -increase BP/HTN • -activation of baroreceptor • -decrease FHR, BP, and CO Late decel: Ans- • Inadequate uteroplacental blood flow-decreased maternal fetal O2 transfer • -activation of chemoreceptors to respond due to increased PCO2, decreased PO2, and decreased pH • -Fetal bradycardia and hypertension Category I: Ans- • Normal fetal acid base status • All the following are required: • Moderate variability • Baseline rate 110-160 • Late or variable decels are absent • Early decels present or absent • Accels present or absent Category II: Ans- • Indeterminate compensatory response • Not category I or II Category III: Ans- • Abnormal fetal acid-base status • Either required • Absent variability with: o Recurrent late decels, or o Recurrent variable decels, or o Bradycardia • Sinusoidal pattern In-Utero resuscitation: Ans- • Change maternal position • Decrease uterine activity • IV fluid bolus • Correct maternal hypotension • Oxygen administration • Amnioinfusion • Alteration in 2nd stage maternal pushing efforts • If prolapsed cord, then elevate fetal presenting part while moving toward operative birth Baseline FHR: Ans- • Approximate mean FHR excluding accelerations and decelerations or periods of marked variability (25 bpm) • Minimum of 2 minutes of identifiable BL segments in any 10 m