An Artificial Placenta Experimental System in Sheep: Critical Issues for Successful Transition and Survival up to One...

Area of Science:

• Biomedical Engineering
• Fetal Physiology
• Neonatal Research

Background:

• The development of artificial placenta (AP) systems is crucial for supporting extremely premature infants.
• Sheep models offer a viable platform for studying AP technology due to physiological similarities with human fetuses.
• Overcoming technical challenges is essential for achieving long-term AP system functionality.

Purpose of the Study:

• To detail the development of an artificial placenta (AP) system in a sheep model.
• To identify and address the learning curve and key bottlenecks in AP system implementation.
• To achieve reproducible fetal survival up to one week using the AP system.

Main Methods:

• Twenty-eight fetal sheep (110-115 days gestation) were connected to an AP system.
• Survival goals were progressively increased across three groups: 1-3 hours, 4-24 hours, and 48-168 hours.
• Key parameters monitored included cannulation time, complications, fetal blood gas levels, heart rate, and extracorporeal circuit performance.

Main Results:

• Cannulation complications significantly decreased from 75% to 0% across study groups (p=0.004).
• Initial fetal pH levels improved, and the success rate of achieving survival goals increased to 80%.
• Early AP system failures were primarily due to cannulation accidents, air bubbles, and thrombosis.

Conclusions:

• Establishing a reproducible artificial placenta (AP) system is complex, requiring significant time, effort, and a multidisciplinary team.
• A defined learning curve enabled reproducible transition and survival of fetal sheep for up to 7 days.
• Enhancing instrumentation with custom-designed devices is necessary for achieving extended fetal survival durations.