NCC EFM - chapter 002 physiology Quiz TEST Bank with Correct Answers 2023 ATESTED

Placenta Functions correct answers Serves as the fetus' extracorporeal life-support system: fetal lung (respiration), kidney (excretion), GI (nutrition), skin (heat exchange), barrier to dangerous substances, endocrine (steroid and proteins production) Blood Flow to Uterus correct answers 85% of total uterine flow to the placental circulation and 15% to the extraplacental uterine musculature What are the two layers that nutrients must cross of the fetal trophoblast? correct answers fetal connective tissue within the villus and the fetal capillary wall Factors that decrease uterine blood flow correct answers 1. Position 2. exercise 3. Contractions 4. Surface area 5. anesthesia 6. hypertension 7. diffusion distance What is the fetal response to maternal exercise correct answers fetal tachycardia- sympathetic response to decreased oxygenation. In severe hypoxia -- fetal bradycardia During a contraction, the intramyometrial pressure... correct answers exceeds the spiral arterial pressure -- spiral arteries collapse and decrease blood flow to fetus Placental abruption/hypertensive disorders/prolonged pregnancy is an example of decreased uterine blood flow via correct answers decreased surface area Anesthesia reduces uterine blood flow by... correct answers causing maternal hypotension due to sympathetic blockade. Correcting with alpha adrenergic agents may not completely restore uterine blood flow because those agents increase uterine circulatory resistence and TPR. Should use a mix like ephedrine (alpha and beta adrenergic stimulator) to correct hypotension. Can also fix problem by changing position and giving fluids. Hypertension result in decrease blood flow to the uterus by: correct answers either acute vasospastic or chronic atheromatous changes. If you lower the blood pressure with treatment, may shunt blood away from intervillous space if other vessels are dilated and uterine vessels are diminished. Two umbilical arteries arise from the correct answers terminal ends of the fetal hypogastric arteries Umbilical vein correct answers returns blood to the fetus from the placenta -- partially through the liver and partially to the IVC through the ductus venosus The well oxygenated blood enters the right atrium and mainly goes to the _________ circulation while blood returning from the SVC from the upper body is channeled principally through the ductus arteriosus to the _______ and ______ correct answers 1. cephalic circulation 2. lower body 3. placenta The fetus can exist at a maximum pO2 below that of the uterine vein and thrives at a lower pO2 by: correct answers 1. fetal hemoglobin concentration is higher -- higher oxygen carrying capacity 2. Fetal cardiac output higher than adult on volume per unit body weight 3. Dissociation curve -- higher saturation at a given pO2. Oxygen crosses the placenta by correct answers simple diffusion