Effects on Recovery of Children Undergoing Elective Surgery: Comparison of Intravenous Formulation of Fentanyl Citrate and Midazolam Administered Orally for Premedication

Effects on Recovery of Children Undergoing Elective Surgery: Comparison of Intravenous Formulation of Fentanyl Citrate and Midazolam Administered Orally for Premedication

Introduction Paediatric preoperative anxiety has been a concerning matter for the past decades with a high prevalence and several adverse outcomes branching into social, developmental, behavioural, and perioperative fields. The anticipation of pain, separation from family, and fear of surgery are few of the factors that trigger perioperative anxiety in children. However, the routine use of anxiolytic premedication before anaesthetic induction is debated. Furthermore, premedication may significantly affect recovery from anaesthesia.

Premedication causes sedation and reduction of anxiety during separation from parents. It also provides a calm and cooperative child for smooth induction of anaesthesia. The oral route of administration of the drugs is the most acceptable and a nontraumatic route, especially in children. The total volume of the oral premedication can be kept at 0.2 ml/kg which is far below the gastric fluid volume of 0.4 ml/kg above which the risk of aspiration increases. Lipid-soluble drugs that can be supplied as water-soluble salts provide the opportunity to use it through oral route of administration for premedication.

The salt fentanyl citrate is soluble in water. These properties suggest that fentanyl citrate can be incorporated for use as a premedicant. This lipid-soluble opioid when placed in normal conditions of the mouth is 80% nonionized, making it the only opioid suitable for transmucosal absorption. However, bioavailability depends on the fraction of the dose that is absorbed through the oral mucosa (~25%) and the fraction that is swallowed (~75%, swallowed dose is only partially bioavailable).

Midazolam, a benzodiazepine, has been routinely used orally for premedication in children scheduled for surgery. Bioavailability of oral midazolam varies from 15% to 27% in children. It has a rapid onset and short duration of action. It is reliable in achieving sedation and anxiolysis. However, search for a better alternative continues due to concerns such as bitter taste, cognitive impairment, long-term behavioural disturbances, paradoxical reactions, hiccups, and respiratory depression.