Shobha Malviya M.D.
University of Michigan Hospitals and Health Center
Ann Arbor, Mi
Why does my child need to be sedated for her MRI scan? I was told that the procedure is entirely painless.
Procedures such as MRI scans require the child to be completely still to ensure adequate quality of the scans. The scanner is a long tunnel, and during the scan there are loud noises similar to a motorcycle engine. This may present a scary and claustrophobic (closed-in) environment for most young children and even some adults. Scans last for 45 minutes to 2 hours depending on the areas to be scanned. Therefore, many children and even some adults require sedation even though the procedure does not cause any pain. The need for sedation is assessed by nurses and doctors responsible for her care in the MRI scanner based on her age, medical history and experience with past medical procedures. Parents may be asked for important information that will help to determine whether or not the child will need sedation.
Why can't my child eat or drink before the MRI?
She cannot eat or drink because she is being sedated for the MRI. Sedative medications may cause the muscles of the throat, esophagus and stomach to relax. This may allow food and other stomach contents to come up into the esophagus and throat and these contents may then go into the windpipe and lungs. This can result in severe lung infections that may even require the child to be hospitalized. To minimize this risk, patients should not eat or drink before sedation.
What are the risks of sedation?
The majority of children undergo sedation safely with no side effects or adverse events. The minor side effects of sedation include nausea, vomiting, mild allergic reactions, headache and dizziness. Some children may experience prolonged or excessive sedation and in some, sedation may fail requiring the procedure to be rescheduled with general anesthesia. Some children may become agitated or restless during or after sedation.
The more serious adverse effects of sedative medications are slowed breathing, decrease in blood pressure or abnormal heart rate and rhythm. These adverse effects are fortunately rare. These risks are further reduced by obtaining a detailed medical history, choosing the best sedative medications based on this history, and by giving the medications in small doses and monitoring their effects closely. Also, careful observation and close monitoring of children during the procedure reduces risk from sedation. The most feared of the risks i.e. death and permanent injury are extremely rare and are further reduced by the above precautions.
How long does the sedation last? Will my child need to stay in the hospital once the procedure is complete? When can she resume her normal activity?
Depending on the sedative medication used and the child's response, some children may be awake at the end of the procedure and ready to go home soon thereafter once specific discharge criteria are met. Children, however, exhibit varied responses to sedatives. Therefore, it is often hard to predict how sedated or sleepy the child will remain after the procedure. Some children may continue to need monitoring and observation in the recovery room until they are awake. Most children, however, are able to resume their normal activity within a few hours after the procedure.
Will any special precautions be needed after my child is sent home?
Depending on the sedative medication used, children may continue to be sleepy and unsteady on their feet for a few hours after the procedure. Therefore, it is recommended that children who are sedated be observed in the car seat during the ride home. Additionally, a responsible adult should stay with the child for a period of 12-24 hours after sedation. Activities that need co-ordination such as swimming, use of playground equipment, climbing, riding a bike, roller-blading or skating should be delayed for 12-24 hours or until parents are sure the child is stable on his/her feet.