Subglottic Stenosis

Subglottic stenosis is a narrowing of the airway in the area between the vocal cords and the trachea, at the narrowest part of a child’s airway.

There are 4 grades of Subglottic Stenosis:

Grade I – less than a 50% obstruction of the airway.

Grade II – a 51% to 70% obstruction of the airway.

Grade III – a 71% to 99% obstruction of the airway

Grade IV – Total obstruction of the airway

This narrowing or obstruction of the airway could be congenital or acquired. Although it is relatively rare, congenital subglottic stenosis is the third most common congenital airway problem, and it accounts for around 5% of all cases. Acquired SGS accounts for 95% of all cases, and is the most common acquired anomaly of the larynx in children and the most common abnormality requiring tracheotomy in children younger than 1 year.

Symptoms of Subglottic stenosis

Babies who have subglottic stenosis could experience a tight whistling or wheezing sound each time they breathe. You may also hear a grunting sound each time your child exhales. Some infants also experience shortness of breath, indicating that she is having trouble breathing or not getting enough oxygen. Recurring bouts of barking cough or croup is also often observed in infants with subglottic stenosis. Usually the symptoms are more apparent if the child’s airway becomes stressed by a cold or other virus.

Causes of Subglottic stenosis

As the name suggests, congenital subglottic stenosis is a birth defect. The airway remains narrow because the airway cartilage did not form properly before birth. Acquired subglottic stenosis often occurs after long periods of intubation and ventilation for respiratory problems. The narrowing is often caused by scarring in the larynx. Other important risk factors include infection, low birth weight, reflux and sepsis.

Risks of Subglottic stenosis

Some infants with very mild subglottic stenosis might not experience any symptoms at all. As the infant grows, their conditions will most often improve over time with the growth of their airways. However, moderate to severe cases will affect the infant’s ability to breathe. The lack of oxygen in the baby’s blood can cause:

-respiratory distress

-poor weight gain

-cyanotic episodes

-recurrent lung infections

Dealing with of Subglottic stenosis

Tracheostomy is usually required as the initial step in the surgical management of patients with subglottic stenosis. A tracheotomy is an incision in the trachea (windpipe) that forms an opening so a tube can be inserted. The tube allows the passage of air to flow and the removal of secretions in the windpipe. Instead of breathing through the nose and mouth, which the child cannot do because of the obstruction in their airway, breathing will now occur through the tracheostomy tube.

Since the tracheostomy tube bypasses the upper airway mechanisms, the air via the tube is cooler, dryer and not as clean. In response to these changes, the body produces more mucus. Generally, the child should be suctioned every 4 to 6 hours to remove mucus from the tube and trachea to allow for easier breathing. Frequency of suctioning will vary from child to child and will increase with respiratory tract infections. Try to avoid suctioning too frequently. The more you suction, the more secretions can be produced.

Infants with subglottic stenosis are often premature or of low birth weight. A tracheotomy allows these patients time to grow before definitive surgical treatment is performed. In most cases, the child will require a throat reconstruction procedure called Laryngotracheoplasty or LTP. This procedure is most successful when it is performed on the child around age 3.

The long term goal in treating subglottic stenosis is to enlarge the airway so that the child can breathe through their windpipe (trachea) and the tracheostomy tube can be removed.

Medical homecare equipment explained:

  • Suction machine

This machine helps to remove excess mucus from your baby’s airway, clearing the path so they can breathe better. The mucus is removed by vacuum through a tube into a canister. The vacuum strength can also be adjusted to suit infants. Your doctor may recommend the use of this machine if excess mucus is a problem for your child.

  • Pulse oximeter

A Pulse oximeter measures the amount of oxygen in the baby’s blood through the skin. A tiny light is taped to the baby’s finger or toe, or in very tiny babies, a foot or hand. A wire connects the light to the monitor where it displays the amount of oxygen in the baby’s red blood cells. Your doctor will advise you on how to interpret the readings, and when to seek medical help.