Fetal Safety During Fetoscopic Spina-Bifida Repair: Anesthetic Concerns

Abstract

Prenatal repair of fetal spina-bifida in the 2nd trimester has been shown to improve neurological function after delivery of the baby. Surgery can be performed with partial delivery of the fetus through a uterine incision, or increasingly via fetoscopy. Trocars to allow surgical instrumentation are introduced either via the exteriorized uterus or percutaneously. Both approaches require maternal anesthesia, an immobile anesthetized fetus and a non-contracting uterus. This can be achieved with administration of a general anesthetic to the mother, transplacental anesthesia of the fetus and tocolytic agents as required. Transplacental anesthesia needs to balance adequate depth of anesthesia for the mother and fetus with rapidly reversible uterine atony. The anesthetist is responsible for the safety of both patients. Monitoring of cardio-respiratory parameters for the mother are well established, but the tools available to monitor fetal well-being and access for corrective therapy are limited. Cardiotocography, fetal echocardiography or ultrasound assessment of umbilical or middle cerebral artery blood flow can be monitored for fetal well-being, but interpretation can be difficult. Fetal blood pressure monitoring is not yet feasible. There is a clear need to enhance fetal monitoring and define normal parameters with clear protocols for intervention to improve fetal safety. Abandoning the procedure should be considered to avoid emergency delivery of an extremely premature fetus. More research into suitable fetal monitoring techniques are needed.

Keywords

Fetoscopy - Fetal surgery - Safety - Anesthesia - Monitoring

Publication History

Received: 28 February 2021

Accepted: 12 May 2021

Article published online:
05 May 2023