Successful intravenous sedation using propofol and remifentanil in a patient with a gag reflex: a case report

Intravenous sedation is a common approach for patients with gag reflex during dental procedures. However, deep sedation can lead to airway obstruction and coughing, hindering treatment. This case report describes the successful use of low-dose remifentanil for intravenous sedation in a 14-year-old intellectually disabled boy（ height: 176 cm, weight: 65 kg） with dental caries, who was referred to our hospital for severe gag reflex and dental phobia. Assessment revealed a gagging severity index of grade IV, and dental treatment was planned under intravenous sedation with preoperative fasting（ normal meals: up to 6 h before sedation, clear liquids: up to 2 h before sedation）. In Treatment 1, midazolam（ 4 mg） and propofol（ target controlled infusion［ TCI］: 2.0‒2.5 μg/mL, total dose: 600 mg） were used for sedation, with a treatment time and sedation time of 86 min and 105 min, respectively. In Treatment 2, remifentanil （0.05‒0.1 μg/kg/min, total dose: 0.3 mg） and propofol（ TCI: 1.8‒2.0 μg/mL, total dose: 447 mg） were used, with a treatment and sedation time of 65 mins and 100 mins, respectively. Frequent coughing and body movement were observed during Treatment 1, resulting in persistent treatment interruptions. Conversely, Treatment 2 provided excellent intraoperative conditions with minimal coughing and improved vital sign stability, although mild respiratory depression was observed. Furthermore, Treatment 1 required airway management via chin lift maneuver due to oxygen desaturations. Regarding recovery time, Treatment 2 exhibited shorter times compared to Treatment 1 due to using a lower propofol dose. Low-dose remifentanil may be useful for intravenous sedation in patients with gag reflex. While this approach offers promise, potential side effects, including respiratory depression and muscle rigidity (leadpipe henomenon), should be considered. Careful monitoring of vital signs and preparedness for possible complications (e.g., airway devices, pharmacological antagonists, neuromuscular blocking agents)are therefore necessary when considering intravenous sedation for dental procedures.