A nasal high-flow system prevents hypoxia in dental patients under intravenous sedation

J Oral Maxillofac Surg. 2015 Jun;73(6):1058-64. doi: 10.1016/j.joms.2014.12.020. Epub 2014 Dec 30.


Purpose: Hypoxia is a major complication in dental patients under intravenous sedation (IVS). A nasal high-flow (NHF) system has been reported to achieve effective oxygenation in patients with sleep apnea syndrome. This study investigated the ability of the NHF system to prevent hypoxia in dental patients under IVS.

Materials and methods: Thirty patients scheduled for dental treatment under IVS were enrolled. Patients were randomly divided into 3 groups: patients spontaneously breathing oxygen at 5 L/minute through a nasal cannula (NC5 group), patients administered oxygen at 30 L/minute through the NHF system, and patients administered oxygen at 50 L/minute through the NHF system. Hypnosis was induced by bolus administration of midazolam (0.05 mg/kg) followed by continuous administration of propofol (target blood concentration, 1.2 to 2 μg/mL). Noninvasive blood pressure, peripheral capillary oxygen saturation (SpO2), heart rate, and bispectral index values were recorded every 2.5 minutes before the induction of anesthesia. Interventions, such as jaw lifting, were recorded during IVS and arterial blood gas analysis was performed at the end of sedation. Patient and surgeon satisfaction with IVS was evaluated by interview.

Results: Minimum SpO2 was lowest in and surgeons were least satisfied with the NC5 group. In addition, interventions were required most frequently in the NC5 group (P < .05). Compared with the NC5 group, use of the NHF system improved partial pressures of oxygen and carbon dioxide in dental patients under IVS (P < .05).

Conclusions: These results suggest that use of the NHF system can prevent hypoxia in dental patients under IVS. Further studies are necessary to determine the appropriate flow rate and indications for NHF in obese patients.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Airway Management / methods
  • Anesthesia, Dental / methods*
  • Anesthetics, Intravenous / administration & dosage
  • Blood Gas Monitoring, Transcutaneous / methods
  • Blood Pressure / physiology
  • Conscious Sedation / methods*
  • Continuous Positive Airway Pressure / instrumentation
  • Continuous Positive Airway Pressure / methods*
  • Electroencephalography / methods
  • Heart Rate / drug effects
  • Humans
  • Hypnotics and Sedatives / administration & dosage
  • Hypoxia / prevention & control*
  • Midazolam / administration & dosage
  • Middle Aged
  • Monitoring, Intraoperative
  • Oral Surgical Procedures / methods*
  • Oxygen / blood
  • Oxygen Inhalation Therapy / instrumentation
  • Oxygen Inhalation Therapy / methods*
  • Patient Satisfaction
  • Propofol / administration & dosage
  • Treatment Outcome


  • Anesthetics, Intravenous
  • Hypnotics and Sedatives
  • Midazolam
  • Oxygen
  • Propofol