Sistem Peredaran Darah Janin (Fetal Circulation)

Summary

This video, presented by Seri Ria Viandri from the D3 Midwifery Program at Poltekkes Kemenkes Riau, explains the fetal blood circulation process. It begins with oxygen and nutrient-rich blood flowing from the placenta to the fetus via the umbilical vein, passing through the liver, vena cava inferior, and heart. The blood is distributed through the atria, ventricles, and lungs to nourish the developing lungs. It then flows to the aorta and is distributed to the body, with deoxygenated blood returning to the placenta. The cycle then repeats. This clear and concise explanation covers the key stages of fetal blood circulation.

Takeaways

• 👶 The fetal circulation system begins with oxygen and nutrient-rich blood from the placenta.
• 🩸 Blood enters the fetus through the umbilical vein (Vena umbilicalis).
• 🫀 After entering the umbilical vein, blood flows into the liver, passing through the ductus venosus, connecting to the inferior vena cava.
• 💡 Blood then reaches the right atrium (Atrium dekstra), where it is divided into two streams.
• 🔄 One stream flows into the right ventricle (Ventrikel dekstra) while the other enters the left atrium (Atrium sinistra) via the foramen ovale.
• 🫁 Blood in the right ventricle flows to the lungs through the pulmonary artery (Arteri pulmonalis), supporting lung development.
• ❤️ Blood in the left atrium moves to the left ventricle (Ventrikel sinistra) and then to the aorta.
• 🔗 Blood in the aorta has two pathways: one towards the pulmonary artery via the ductus arteriosus and the other towards the rest of the body.
• ♻️ Carbon dioxide-rich blood from the body returns to the umbilical arteries (Arteri umbilikalis) and flows back to the placenta.
• 🔄 This cycle repeats, ensuring continuous circulation of blood between the fetus and the placenta.

Q & A

What is the starting point of fetal blood circulation?

Fetal blood circulation starts with oxygen-rich and nutrient-rich blood from the placenta entering the fetus through the umbilical vein (Vena umbilicalis).

What is the role of the ductus venosus in fetal circulation?

The ductus venosus connects the umbilical vein to the inferior vena cava (Vena cava inferior) and helps bypass the liver, allowing oxygenated blood to flow directly to the heart.

What happens to blood when it reaches the right atrium (Atrium dekstra)?

In the right atrium, the blood is divided into two pathways: some goes to the right ventricle (Ventrikel dekstra), while some passes through the foramen ovale into the left atrium (Atrium sinistra).

What is the function of the foramen ovale in fetal circulation?

The foramen ovale allows blood to bypass the lungs by flowing from the right atrium to the left atrium, facilitating efficient oxygenation of the body.

How does blood flow to the lungs in fetal circulation?

Blood from the right ventricle flows to the lungs through the pulmonary artery (Arteri pulmonalis) to provide nutrients to the developing lungs, but most of it bypasses the lungs since they are not yet functional.

What happens to the blood in the left atrium (Atrium sinistra)?

Blood in the left atrium flows into the left ventricle (Ventrikel sinistra) and is then pumped into the aorta to supply the body with oxygen-rich blood.

What is the role of the ductus arteriosus in fetal circulation?

The ductus arteriosus connects the pulmonary artery to the aorta, allowing most of the blood to bypass the lungs and go directly into systemic circulation.

How does deoxygenated blood return to the placenta?

Deoxygenated blood, rich in carbon dioxide, flows through the umbilical arteries (Arteri umbilikalis) back to the placenta, where gas exchange occurs.

Why do the lungs not play a major role in fetal oxygenation?

The lungs are not fully developed and do not function in gas exchange during fetal life, so most of the blood bypasses the lungs through the foramen ovale and ductus arteriosus.

What is the significance of the placenta in fetal circulation?

The placenta is essential in fetal circulation because it is the site where oxygen and nutrients are exchanged between the mother and fetus, ensuring the fetus receives oxygenated blood.