Relias - Fetal Heart Monitoring Notes and Summary
uterine blood supply -: - 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 -: *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 -: - 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 -: 1 - reduce O2 in blood
2 - reduced O2 delivery at tissue level
, Fetal anaerobic metabolism -: - 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 -: pH below 7.35
pH is low
(acidosis is the process that leads to low blood pH, or acidemia)
alkalosis -: pH above 7.45
pH is high
buffers -: - help maintain acid base homeostasis
- 2 major fetal buffers are plasma bicarbonate and hgb
base excess and base deficit -: - 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 -: - 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
uterine blood supply -: - 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 -: *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 -: - 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 -: 1 - reduce O2 in blood
2 - reduced O2 delivery at tissue level
, Fetal anaerobic metabolism -: - 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 -: pH below 7.35
pH is low
(acidosis is the process that leads to low blood pH, or acidemia)
alkalosis -: pH above 7.45
pH is high
buffers -: - help maintain acid base homeostasis
- 2 major fetal buffers are plasma bicarbonate and hgb
base excess and base deficit -: - 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 -: - 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
