RELIAS - Fetal Heart Monitoring Exam Questions with Actual Answers.

RELIAS - Fetal Heart Monitoring Exam Questions with Actual Answers. uterine blood supply - CORRECT ANSWER - uterine arteries deliver oxygenated blood to spiral arteries which bring oxygen rich blood to intervillous space of placenta that has fetal capillaries - fetal capillaries carry the O2 rich blood to umbilical VEIN that goes to fetus -in contrast, the umbilical ARTERIES return waste products to that intervillous space that go into mother's venous system Potential issues that negatively affect fetal oxygenation - CORRECT ANSWER *Maternal Oxygenation:* asthma, hyper- or hypo- ventilation *Maternal Circulation:* decreased maternal cardiac output, hypotension, decreased Hgb *Placental O2 and CO2 Exchange:* postterm, abruption, HTN, hypotension, uterine tachysystole *Fetal circulation:* cord compression or occlusion Fetal hypoxemia - CORRECT ANSWER - can occur d/t reduced fetal O2 reserves, excessive uterine activity, or reduced uteroplacental blood flow - worsening fetal hypoxemia can lead to abnormal FHR patterns, mostly minimal or absent variability from acidemia (1) hypoxemia vs. (2) hypoxia - CORRECT ANSWER 1 - reduce O2 in blood 2 - reduced O2 delivery at tissue level Fetal anaerobic metabolism - CORRECT ANSWER - occurs when long term O2 delivery is insufficient to meet cellular needs of tissues - results in production of lactic acid and other noncarbonic acids - ACIDOSIS is the presence of excessive acids in tissues acidosis - CORRECT ANSWER pH below 7.35 pH is low (acidosis is the process that leads to low blood pH, or acidemia) alkalosis - CORRECT ANSWER pH above 7.45 pH is high buffers - CORRECT ANSWER - help maintain acid base homeostasis - 2 major fetal buffers are plasma bicarbonate and hgb base excess and base deficit - CORRECT ANSWER - base deficit is expressed as a positive number - base excess is expressed as a negative number ~ they are equivalent and terms are used interchangeably ~ fetal acidosis - CORRECT ANSWER - when O2 is decreased to fetus, tissue hypoxia results in acidosis, which then shows a drop in pH, a loss of bicarb, and increase in base deficit acidemia - CORRECT ANSWER assoc w/ widespread, deleterious effects on vital organ and body function fetal hypoxia during birth - CORRECT ANSWER assoc w/ neonatal depression, low apgars, neonatal encephalopathy, and cerebral palsy respiratory acidosis - CORRECT ANSWER *low pH (< 7.10), high pCO2 (> 60), normal base deficit ( < 12)* - increase of pCO2 for fetus that lowers pH but doesn't affect base deficit factors that contribute to resp acidosis - CORRECT ANSWER - sudden decrease in placental or cord perfusion - uterine tachysystole - maternal hypoventilation metabolic acidosis - CORRECT ANSWER *ph < 7.10 , normal pCO2 (<60), high base deficit (>12)* - a higher base deficit (such as > 12) has been assoc w/higher risk for severe neonatal complications - most common cause of metabolic acidosis in fetus is r/t inadequate O2 delivery - prolonged hypoxic insult to fetus results in depletion of bicarb, which is a base buffer that normalizes pH levels mixed acidosis - CORRECT ANSWER *pH < 7.10 , high pCO2 > 60, and high base deficit >12* - may develop when resp acidosis persists for a prolonged period of time