Glenn Procedure

Overview of Glenn Procedure in India

Glenn procedure is a heart surgery which is done when the normal blood circulation of the heart is interrupted in a baby because of an issue. The Glenn procedure is a new route of the blood flow bypassing the area of the heart that is affected and going straight to the lungs to have the blood oxygenated. In the event that the heart is not working on a normal basis and is not able to supply the entire body with oxygen, then to restore the blood flow that supplies the body with oxygen, the Glenn procedure is carried out. 

The Glenn surgery is done between 3-6 months in which the baby is born and it can also demand another surgery several years later to provide a permanent cure to the disrupted blood circulation. The Glenn procedure is used in a great number of congenital conditions. Glenn procedure is not commonly done as it presents few risk and complications. Intensive care can be given to the Glenn procedure several days after the operation. The recovery process is not fixed but it normally takes a few months. Glenn procedure has a success rate of approximately 99%. During the last several years, the Glenn procedure has increased the survival rate of babies born with congenital heart disease to some extent.

What Is The Glenn Procedure?

The Glenn Procedure, also known as a form of Bidirectional Glenn Procedure or the Glenn Shunt, is a surgical procedure used to improve blood flow through an underdeveloped chamber (right or left atrium) of the heart. The procedure involves the connection of the superior vena cava (SVC) to both pulmonary arteries, allowing for deoxygenated blood to flow directly from the upper body, through an artificial shunt, and into the lungs to receive oxygen.

The SVC is a vein that transports deoxygenated blood from the upper body back to the heart. Normally the SVC would deliver deoxygenated blood to the right atrium and through the tricuspid valve to the right ventricle, and then on to the pulmonary artery to receive oxygen. By transforming the SVC to bypass the defect or area of concern (most commonly the tricuspid valve), the Glenn Procedure allows for deoxygenated blood to go from the upper body through the SVC to the lungs to become oxygenated.

The Glenn Procedure is typically performed after one or more surgical procedures are performed shortly after birth, although infants may undergo a subsequent procedure to accomplish a more permanent fix as they grow older (usually within 1-2 years).

What Does The Glenn Procedure Do?

The bidirectional Glenn procedure helps people born with certain heart defects get better blood flow. Most of the time, the problem is a single ventricle defect—basically, one of the heart’s valves or lower chambers just doesn’t work well or is too small to do its job. So, the Glenn procedure steps in to reroute the blood and give the heart a hand.

Types of Glenn Procedure:

Bidirectional Glenn (BDG) Procedure

The Bidirectional Glenn operation is generally considered a second step in creating a functioning circulation. This operation disconnects blood vessels that carry deoxygenated blood from the right atrium of the heart and connects them to pulmonary arteries (the blood vessels between the heart and lungs). This procedure provides a new route for deoxygenated blood from the upper body to flow directly into the lungs. The procedure is essential in the comprehensive treatment of congenital cardiac defects; deoxygenated blood is unable to traverse the defective region of the left ventricle.

Hemi-Fontan or Unidirectional Glenn Procedure

The Hemi-Fontan is basically a variation of the Glenn procedure. In this surgery, doctors connect the main vein carrying deoxygenated blood from the upper body to the right side of the vessel that sends blood to the lungs. They usually do this as a temporary step before moving on to the full Fontan procedure. This approach helps the body get more oxygen and takes some pressure off the heart’s single lower chamber. It’s a good option for kids with complicated congenital heart problems.

Procedure:

The overview of the Glenn procedure is described below:

Before the procedure

Generally, patients with prior Blalock-Taussig (BT) shunts or pulmonary artery banded hearts will need Glenn cardiac surgery to help increase the blood flow to their heart and lungs after the BT shunt/PAB has been placed, as both of these procedures limit the total amount of blood being pumped through the lungs & looping around back to the heart.

Prior to their surgical procedure, your child's cardiologist will need to:

• Perform a cardiac catheterisation or heart MRI to assess the anatomy of the child.
• Know the names and dosages of all of the child's medications (both prescription and over-the-counter).

During the procedure

Anesthesia: Anesthesia is done before the operation such that at the time of surgery, the patient will be unconscious.

Access: The surgeon creates an opening in the chest in order to reach the blood vessels. The depth and location of the incision may differ based on the patient or the surgeon.

Cardiopulmonary Bypass: Sometimes, the patient can be placed on a heart-lung machine that is designed to carry out the pumping of blood temporarily. It is a machine that is applied in various forms of heart and lung operations. This gives the surgeon the opportunity to operate the heart without having the heart to beat.

Isolation of blood vessels: The surgeon divides the large artery that supplies the heart with deoxygenated blood of the upper body.

Anastomosis: It is the most crucial point of the Glenn procedure when a connection between the isolated blood vessel supplying deoxygenated blood and the blood vessel supplying blood to the lungs is created. It is through this connection that the deoxygenated blood of the upper body flows straight into the lungs without being pumped to the region of the heart that is affected.

Closure: This is done by the surgeon after the Glenn procedure; he/she uses sutures to close the incision.

Monitoring and Recovery: This involves closely following the patient after the surgery to make sure that blood flows normally. The process of recovery might also be different in each patient yet it can take a few days in the hospital.

After the procedure

After your child has had surgery, the surgical staff will monitor your child in the intensive care unit (ICU) for several days to weeks before they return to their baseline levels of oxygen saturation. Some children with a single ventricle who have undergone a Glenn procedure will not necessarily need to have a Fontan procedure in the future. If your child does require a Fontan procedure, it will allow them to have separate systems for moving oxygen from the lungs to the blood and for distributing oxygenated blood throughout their body.

Your baby's body can be affected by the Glenn procedure for a long time until they receive their final surgery, which is the Fontan procedure and occurs when children typically start to walk. However, when your child becomes more active, it is possible that their physical activity could decrease their oxygen levels further than they already are.