Intrauterine fetal resuscitation

The delivery of oxygen to the fetus is dependent on adequate maternal blood oxygen concentration, uterine blood supply, placental transfer and fetal gas transport. Any disturbance in these factors, singly or in combination, can result in progressive fetal hypoxia and acidosis. The term fetal distress is non-specific but is usually applied to certain characteristic features on electronic fetal monitoring, confirmed if possible by fetal blood sampling. The aim of intrauterine fetal resuscitation (IUFR) measures is to increase oxygen delivery to the placenta and umbilical blood flow in an attempt to reverse fetal hypoxia and acidosis, so that labour may continue safely or to improve the fetal condition whilst arranging urgent delivery. IUFR measures include maternal re-positioning into left lateral, or alternatives (i.e. right lateral or knee–elbow if necessary), rapid infusion of 1000 ml crystalloid (except in fluid-restricted or pre-eclamptic patients), decreasing uterine contractions by stopping oxytocics and administering acute tocolytics (terbutaline 250 μg SC or IV, glyceryl trinitrate 60–180 μg IV or sublingual spray, two puffs). A vasopressor (i.e. ephedrine) may be required in cases of maternal hypotension.