The effects of hypoxemia in COVID-19 on the fetus
By and large, acute variation in the oxygen delivery rate does not alter
fetal oxygen uptake until its delivery falls to a substantially lower
rate(5). This is due to the fetal capacity to increase oxygen extraction
and coordinated fetal cardiovascular response(6). Nevertheless, it is
essential to remember that the CO2 and
O2 gradients allow the diffusion of gases across the
placenta. As opposed to unfavorable effects on the mother’s compensatory
mechanisms, normocapnia favors the fetus, as reduced CO2alveolar tension increases alveolar O2 tension and
prevents the right shift in the oxygen-hemoglobin dissociation curve.
These are fundamental physiologic changes in pregnancy that must be
accounted for when adjusting ventilatory settings.