There are two main factors to consider in a discussion of anesthesia in people with Down syndrome (DS):
Many people with DS will undergo anesthesia more frequently than people without DS.
People with DS are at an increased risk for complications from anesthesia.
People with Down syndrome undergo anesthesia for a variety of procedures. This includes surgeries that most people are provided anesthesia such as heart surgery, many abdominal surgeries, and others. Additionally, a person with DS may require anesthesia for a procedure or a diagnostic test that someone without DS may be able to have done with minimal or no sedation. For example, some people with DS require anesthesia to undergo an MRI scan or require general anesthesia to undergo dental procedures that are typically done with local anesthesia. In addition, people with DS more commonly have a variety of health conditions that may require procedures and thus, may be exposed to anesthesia more frequently. For these reasons, more people with DS are likely to require anesthesia.
People with DS are also at an increased risk for complications from anesthesia for a variety of reasons including anatomical and physiological differences, higher rates of certain co-occurring conditions, and communication challenges.
Types of anesthesia and sedation
Before further explaining the potential risks, here is a brief summary of the different methods of anesthesia and sedation available:
Local anesthesia - An injection is given that numbs one small area of the body. The individual stays alert and awake.
Conscious or IV sedation - An injection is given that includes a mild sedative to relax the individual and pain medicine to relieve pain. The person stays awake but may not remember the procedure afterwards. Sometimes an oral medication is given to begin the sedation, particularly if the person has difficulty allowing an IV to be placed. The oral medication may initiate relaxation allowing the IV to be placed.
Regional anesthesia - An injection is given in a certain area to block pain in that area of the body, such as an arm or leg. Many people are familiar with epidural anesthesia, a regional anesthesia sometimes used in childbirth, delivered via an injection into the person's back.
General anesthesia - This type of anesthesia affects the whole body. The individual goes to sleep and feels nothing and has no memory of the procedure afterwards.
Since general anesthesia will typically have more risk, sometimes one of the other types may be appropriate and substituted for general anesthesia. On the other hand, general anesthesia may be the safest from the standpoint that the person is pain-free, unaware of the procedure being done, and not able to interfere with the safe completion of the surgical or diagnostic procedure. For this discussion, we will focus primarily on general anesthesia.
What are factors in people with DS that might increase the risk of general anesthesia?
Communication and cooperation
The ability to communicate symptoms, discuss treatment plans, and report effects and side effects of treatments can be significant factors in improving an individual’s health. The inability to do so can negatively impact care. This is true for anesthesia in people with DS as it is for other treatments. Communication limitations and other factors may impair the person’s ability to cooperate with the procedure which can increase risk. Helping the person better understand and prepare for the procedure can reduce fear and improve cooperation for some. Using pictures or videos of the process of the upcoming procedure can be helpful.
Dysphagia, impaired swallowing, is more common in people with DS. Before, during, or after anesthesia, impaired swallowing can contribute to aspiration of saliva. When saliva is aspirated into the airway, it can reduce airflow and when aspirated into the lungs, it can cause pneumonia. An anesthesiologist who is aware that this complication is more common in people with DS can provide appropriate protection of the airway to limit the risk of aspiration.
Sleep apnea and airway size
The airways of people with DS are often smaller which can make intubation (putting the breathing tube into the airway) more difficult, make it more likely the airway gets blocked during anesthesia, and contribute to poorer flow of air/oxygen during anesthesia. Similarly, with obstructive sleep apnea (the most common type of sleep apnea in people with DS), the airway can become even more occluded or smaller as the person sleeps. Sleep apnea also increases gastroesophageal reflux disease (GERD). See below for more information. Low tone of the tissues in the airway may also result in collapsing or narrowing of the airway particularly when the person is under anesthesia.
Obesity is more common in people with DS. Obesity can make intubation (putting the breathing tube into the airway) more difficult, reduce airway size, and contribute to sleep apnea, all of which can increase the risk.
Gastroesophageal reflux disease (GERD)
People with DS have a higher incidence of the contents of the stomach “going backwards” up into the esophagus. This material can reflux all the way up the esophagus (especially when lying flat) and enter the airway. This can be a dangerous situation in the operating room. The anesthesiologist can be particularly cautious with the airway to prevent this problem.
Congenital heart disease
Approximately 40-50% of children with DS are born with heart disease which is typically structural including holes in the septum (the wall between the heart chambers) and abnormal valves. Most adults with DS who had these abnormalities have had surgical repair. Even after surgical repair, heart function may not be ideal. Undergoing anesthesia can further temporarily impair heart function including the effectiveness of the heart to pump blood and the normal beating of the heart (electrical activity of the heart). Prior to undergoing anesthesia, an evaluation by a cardiologist, particularly one knowledgeable in adults with congenital heart disease, can make sure the heart function is optimal for anesthesia and reduce the risk of complications.
Atlantoaxial instability (AAI)
People with DS have higher incidence of cervical subluxation, a condition in which the vertebrae in the neck slip forward or backward which can cause injury to the spinal cord. Most commonly this occurs at the joint between the first and second vertebrae in the neck and is called atlantoaxial instability (AAI). If someone has AAI, if the neck is extended (the head tilted back) during anesthesia to place the breathing tube (intubation), the spinal cord could be injured.
In the past, the recommendation was to do x-rays of the neck to assess for AAI before surgery with the assumption that, if the x-rays were normal, then this would not be a concern. However, the recommendation now is that each person with DS be treated as if they have AAI when undergoing anesthesia whether or not the x-ray shows AAI. This protects even those with AAI that was not evident on x-ray.
Additionally, x-rays are no longer recommended as part of the pre-surgical evaluation. Instead, the pre-anesthesia assessment should include asking questions about potential symptoms of AAI and doing a physical exam to assess for signs of AAI. If there are signs or symptoms, more evaluation may be indicated prior to the procedure. However, even if the evaluation is negative for signs and symptoms of AAI and even if a neck x-ray was done and was normal, the general rule is to treat all people with DS during anesthesia as if they have AAI so that extra caution is provided for neck stability. When the person is intubated, a fiberoptic device is used that allows visualization of the airway for intubation without the need to extend the neck.
Additional information about AAI can be found in the Global Medical Care Guidelines for Adults with Down Syndrome.
Other questions to consider before undergoing anesthesia or surgery are:
Has the person had any recent illnesses?
For example, it is recommended to delay elective surgery after having COVID-19 infection. The recommended length of postponement depends on the severity of illness caused by COVID. For more information, please see this reference from the American Society of Anesthesiologists.
Have any steroid medications (e.g., prednisone) been used recently or chronically?
Have there previously been complications during anesthesia and/or surgery? What were they?
The anesthesiologist will want to know what has occurred in the past. Although it is not common, one high risk complication of anesthesia is malignant hyperthermia in which the person’s body temperature goes dangerously high, the muscles contract, and oxygen use/needs go up. We could find no data as to whether this has been found in people with DS and we have not had a patient have this complication.
Is there a history of easy bruising or bleeding?
Is there family history of anesthesia complications, bleeding disorders, malignant hyperthermia, or other medical conditions that increase anesthesia or surgical risk?
What is the individual's fitness level?
A general assessment of fitness can help determine whether further evaluation is required prior to anesthesia. For example, if the person cannot do light housework, wash dishes, climb a flight of stairs, or walk uphill without developing problems with breathing, then further evaluation may be indicated to assess fitness for anesthesia.
Has there been recent unexplained weight loss?
For a variety of reasons, many people with DS are more likely to have surgical or diagnostic procedures that require anesthesia. With careful evaluation for and attention to a variety of health conditions (several of which are more common in people with DS), people with DS can safely undergo anesthesia.
More information on anesthesia can be found in the following resources:
Article from the National Institutes of Health
Article from the National Down Syndrome Society