Different Doses of Sevoflurane During Induction of Anesthesia on Emergence Delirium in Children

Emergence Delirium in Children: a Randomized Clinical Trial of Different Doses of Sevoflurane During Induction of Anesthesia

The investigators aim to reduce the incidence of emergence delirium in children aged 2-7 years old by using two different doses of sevoflurane during inhalatory induction of anesthesia.

Sevoflurane is an inhalational agent widely used in general anesthesia, both for induction and maintenance of anesthesia. It is not irritative on the airways and has a pleasant smell. Within their properties are: low partition coefficient blood / gas (rapid induction and awakening), low heart, liver and kidney toxicity. Inhalational induction in pediatric anesthesia with this agent is frequent to avoid vein puncture in awake patients and is generally done with maximum doses available to obtain a fast loss of consciousness.

Emergence delirium (ED) is frequent in children. It is defined as a mental disorder during recovery from general anesthesia that may include hallucinations, delusions and confusion expressed by crying, restlessness and involuntary physical activity. It usually lasts for 30 minutes and is not necessarily related to pain. During this episodes, children can hurt themselves or others, lose vascular catheters or other invasive devices. ED can generate anxiety and stress in caretakers, delay transfer from Post-Anesthesia Care Units (PACU), increase costs of medical attention and increase use of opioids or other sedatives.

Many interventions have been used to decrease the appearance of ED such as dexmedetomidine, clonidine, benzodiazepines, propofol among others but with no consistent results. The use of sevoflurane has been linked with ED in children and it can induce seizures in high doses (over 2 MAC).

The aim of this study is to test whether using a lower dose of sevoflurane (5%) during induction of anesthesia in children results in less ED than using higher doses (8%).

Inclusion Criteria:

• Surgery with caudal block: circumcision (phimosis), hernioplasty (inguinal hernia)
• American Society of Anesthesiologists (ASA) classification of I or II

Exclusion Criteria:

• Use of Total Intravenous Anesthesia (TIVA)
• Familiar or personal history of Malignant Hyperthermia
• Contraindication to caudal block
• Parents or legal guardians do not sign informed consent