Induction agents are the drugs used to get a child "off to sleep." An anesthetic sleep is not like a normal sleep. During normal sleep a child would awaken if stimulated. This does not happen during an anesthetic sleep if sufficient amounts of anesthetic are given. It is important for your child to understand this.
Many children in the 6- to 12-year-old range are especially concerned about this and need to be reassured that they will be pain-free and totally unaware that they are having an operation. A six-hour operation may seem like only a few minutes to the child under a general anesthetic.
The method and drugs used during the induction of anesthesia depend on a variety of factors including the age of the child and his or her medical condition. The induction of anesthesia will be one of the topics the anesthesia team member will discuss with you the day before surgery.
Some children coming for surgery arrive at the hospital on the morning of surgery. The majority of children will not need to have an IV placed before they are asleep. These children can be induced using an "inhalational anesthetic" (gas), usually sevoflurane.
A sedated child is generally able to breathe off to sleep without becoming upset or anxious. All procedures that could cause pain (starting IVs, etc.) are performed after the child is under the anesthetic, so the child will not be aware that the procedures are happening.
Children with certain types of heart disease may or may not be able to tolerate an inhalational (gas) induction. Children who fall into this group include those with severe heart failure, significant pulmonary hypertension, and those with severe aortic stenosis.
If the anesthesia team decides your child is not a good candidate for an inhalation induction, one of two options may be used.
The child may have an IV placed and receive an intravenous induction drug (fentanyl, etomidate or ketamine), or the anesthetic may be administered as an intramuscular injection.
The drug most commonly used in this way is ketamine. Teenagers or young adults with heart defects that do not produce serious symptoms may receive the drug propofol as an induction agent.
In children under 6 months of age, the anesthetic will primarily consist of high dose fentanyl. Fentanyl does however depress the drive to breathe. As a result, infants receiving a high dose fentanyl anesthetic will require a ventilator for at least six to 12 hours after surgery.
Since most of these patients will require breathing support because of their heart problems, the use of fentanyl in infants with complex heart defects is not a problem.
Many children will also be given an inhalation anesthetic such as sevoflurane or desflurane, which provides amnesia, unconsciousness and analgesia.
Among children not receiving inhalation anesthetics, many will receive midazolam, which provides amnesia, in addition to a narcotic like fentanyl.