Gastric POCUS, 3-Part Episode

Engorgement of epidural veins during advanced pregnancy leads to an increased risk of inadvertent vascular injection and also a decreased necessary dose of epidural or spinal anesthetics. Improved uteroplacental perfusion in conjunction with more effective uterine activity can result from decreased circulating maternal catecholamines. Effective epidural analgesia blunts the "hyperventilation-hypoventilation cycle" that occurs with episodic pain: this prevents further maternal respiratory alkalosis, which may cause a left-shift of the oxyhemoglobin curve and potentially decrease oxygen delivery to the fetus. A randomized prospective study of nulliparous women in spontaneous labor showed that CSEs administered before 4 cm of cervical dilation resulted in a more rapid 1st stage of labor and did not result in an increased rate of cesarean or instrumented deliveries.