Safe Administration of Propofol for Sedation in Children

Purpose Advances in minimally invasive radiological and surgical techniques demand that increasing numbers of children are given sedation or anesthesia to facilitate these procedures, frequently performed on an out-patient or day-care basis. Most are performed outside the operating room environment, with intensivists and emergency physicians administering over 55 % of sedation episodes, and only 19% being performed by anesthesiologists in North America. It is well documented that risks of complications during sedation exceed those experienced during the much more controlled environment of general anesthesia, with a twelve-fold increased risk of mortality when sedation is administered outside the operating room.

Sedative agents have traditionally been administered orally to children. However, characteristics of oral sedation drugs, such as unpredictable depth and duration of sedation resulting from variable drug absorption and prolonged duration of drug effect, have resulted in both high failure and complication rates. Recently, intravenous (IV) anesthetic drugs with more accurately titratable and predictable characteristics have gained popularity for a variety of sedation procedures. Propofol is the most commonly used intravenous agent for these procedures in North America.

Hypothesis The maximum safe infusion rate for an induction dose of propofol administered to children for sedation can be reliably predicted. Safety will be optimized by preventing apnoea whilst minimizing the time for induction of sedation and ensuring an adequate depth of sedation is achieved.

Justification Propofol is an intravenous (IV) anesthetic agent used for induction and maintenance of anesthesia in both adults and children. Propofol has several characteristics favouring its use, including an accurately titratable depth of anesthesia, cardiovascular stability, suppression of upper airway reflexes, rapid recovery with reduced post-operative nausea and vomiting and overall earlier return to pre-anesthetic functional state. At lower doses, propofol may also be used to maintain a level of sedation for radiological imaging or endoscopic investigations.

While propofol provides many advantages it does cause significant respiratory depression. Adverse respiratory events have been reported to be similar in both adults and children. Propofol induced respiratory depression may lead to hypoxemia requiring the provision of supplemental oxygen by mask and/or manual positive pressure ventilation.8 Artificial ventilation requires significant expertise and if poorly managed may result in gastric insufflation, pulmonary aspiration or hypoxia, all of which can lead to devastating complications such as permanent brain injury or death. The maximum dose or rate of administration of propofol that causes respiratory depression in children has yet to be accurately defined. Age specific effects have also not been reported.