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  • Writer's pictureLouie Romanos

Conscious sedation for the Pediatric dental patient

Anesthesiologists, anesthesia assistants, intensivists, respiratory therapists, and dentists have a fundamental obligation for ensuring patient safety when using sedation during surgical procedures. Accomplishing this goal during conscious sedation requires knowledge about the specific inhalational and parenteral agents used during the induction, maintenance, and emergence phases of the anesthesia continuum.

Conscious sedation is described by the Royal College of Dental surgeons of Ontario (RCDSO) as either “mild sedation” or “moderate sedation” (1). Patients receiving mild or moderate levels of sedation have their airway reflexes intact, a decreased level of consciousness (LOC), and minimal cardio-vascular and respiratory depression (1).

Methods for delivering minimal or moderate sedation in the pediatric population involves either:

  1. Minimal sedation: administration of nitrous oxide and oxygen or oral administration of a single sedative drug (1).

  1. Moderate sedation: oral administration of a sedative drug with or without nitrous oxide and oxygen or parenteral administration of a sedative (1).

There are subtle differences in the depth of sedation provided by minimal and moderate techniques however, the signature feature of both approaches is that patients are able to respond normally or purposefully to verbal and/or tactile stimulation (1).

Patient safety during conscious sedation starts with careful patient selection. This involves a systematic pre-procedural assessment highlighting:

  • The patient’s medical history (2). The medical history should include the patient’s presenting issue; co-morbidities; allergies; anesthetic history if any; current medications.

  • A physical examination with particular emphasis on the upper airway (2)

  • Assignment of American Society of Anesthesiology Score (ASA) (2)

Out-of-hospital based sedation should be limited to healthy patients or patients with a mild, controlled systemic disease (ASA 2) (2).

Figure 1: SOAPME- an acronym used for the planning and preparation of a surgical procedure (6)

A child’s behavior can provide the dental professional with invaluable insight concerning the likelihood for successful conscious sedation (2). Behavioral characteristics more likely associated with increased complications include:

A) impulsivity

B) inflexibility

C) shyness

D) emotionality

E) difficulty with dealing with new situations (2)

Behavioral characteristics more likely associated with positive outcomes include:

A) adaptability

B) persistence

C) the ability to self-regulate (2)

Children who are shy, cling to parents, have a difficult time tolerating simple tasks (such as dental prophylaxis or radiographs), and are unwilling to interact with the clinician, may be better suited for alternative methods of behavioral guidance including general anesthesia or delayed treatment (2).

An important strategy used by anesthesiologists and other medical professionals when creating anesthesia plans is the use of local anesthetics. The benefit of local anesthetics is that they improve the patient’s pain experience while allowing for the use of lower amounts of sedatives. Sedation practice has often been described as a continuum (2). As stronger medications and larger doses are administered, the depth of sedations shifts toward moderate sedation, deeper sedation and potentially general anesthesia (2). Excellent local anesthesia can provide profound analgesia and keep the child in a state of mind that facilitates good sedation (2).

The most common inhalational agents and/or drugs used for providing mild to moderate levels of anesthesia during conscious sedation are: nitrous oxide and oxygen mixtures and benzodiazepines.

Nitrous oxide (N2O) and oxygen (O2) mixtures These two gases can be combined in varying proportions and have many properties including: anxiolytic, sedation, analgesia, and muscle relaxation (3). It has a long history of safe use providing moderate sedation for minimal to moderately painful procedures (3). Care must be taken when used in combination with other sedatives as deeper levels of anesthesia may result (3). It can facilitate the provision of more complex, time-consuming procedures and dental extractions particularly for young and anxious patients undergoing orthodontic extractions (3). It has a rapid onset, rapid emergence, wide safety margin, and is a poor analgesic (3). Dose of N2O is 50% with 50% O2 is standard but lower and higher doses of N2O are also common (3). Doses greater than 70% N2O should never be used secondary to the possibility for delivering hypoxemic gas mixtures (3).

Figure 2: N2O and O2 delivery via nasal hood

A typical process for administering N2O/O2 mixtures is as follows:

1.The patient is allowed to breath in 100% O2 using a nasal hood at a flow rate of 6 LPM for a duration of 5 minutes (4). This process allows for pre-oxygenating the patient and preventing oxygen desaturations associated with hypoventilation and potential airway obstruction.

2. After 5 minutes of O2 pre-oxygenation, N2O was titrated during a 5-minute period until and ideal level of sedation was achieved (4). Some of the patient characteristics associated with an ideal sedation level include: a feeling of light-headedness; a feeling of warmth throughout the body; numbness of the hands and or feet; a feeling of euphoria; and a feeling of lightness or heaviness of the extremities (4).

3. Once this level is achieved, the patient is maintained at this level for a period of 5 minutes followed by injection of a local anesthetic (4).

4. The procedure is then initiated and when completed, the patient is usually recovered on 100% O2 for 5-minutes (4).

5. The patient is discharged to his or her parent when discharge criteria have been met.


Figure 3: vial of Midazolam

They provide anxiolysis, sedation/hypnosis, skeletal muscle relaxation, anterograde amnesia, respiratory depression, an anti-convulsant effect but have no analgesic properties (3). They are usually combined with N2O and O2 mixtures as this combination produces an analgesic effect (3). Midazolam is the most common benzodiazepine used during conscious sedation because of its rapid onset, short duration, and rapid emergence (3). It has multiple routes of administration including oral, intramuscular, intravenous, rectally, and intranasally (3). Dose for under 25kg is .3-.5mg/kg but should only be given in an operatory properly equipped with monitoring, rescue equipment, medications, and the benzodiazepine reversal agent Flumazenil (3).

A typical process for administering a pre-medication (Midazolam) with nitrous oxide and oxygen is as follows:

1. Oral administration of .7mg/kg Versed given 15 minutes pre-operatively (5). Versed can come in a 15mg/3ml formulation and delivered as a syrup in addition to other routes of administration (5).

2. Topical anesthesia in the form of benzocaine gel (20%) is applied to the dry mucosa adjacent to the tooth that will be receiving dental work (5). Lidocaine 2% with 1:80000 adrenaline is given to each quadrant (5).

3. Sedation initiated using 90% O2 and 10% N2O via nasal mask. The N2O concentration is increased by 10% at every 1-minute intervals until a concentration of 40% is met (5). Dental treatment is performed at this time (5).

4. After treatment completion, the patient is recovered on 100% O2 and discharged when discharge criteria have been met (5).

To summarize, office-based sedation is feasible and can safely be delivered when the appropriate circumstances exist. The type of surgical procedure being performed and a comprehensive patient assessment should be considered before determining a patient’s suitability for conscious sedation. Benzodiazepines and N2O/O2 combinations are excellent choices for creating optimal patient sedation. They have a rapid onset of sedation and short time to peak concentration allowing dental work to be performed immediately. The short half-life of both options allows for rapid emergence from sedation. This means shorter recovery times and adds to improved patient flow through the dental clinic. Benzodiazepines and N2O/O2 combinations have wide safety margins and can be titrated rather quickly to deliver optimal patient stability during the use of sedation.

Despite all the benefits associated with using Benzodiazepines and N2O/O2 combinations for delivering mild or moderate levels of sedation in pediatric patients, risks or complications can still happen. Over-sedation can cause respiratory depression, cardiovascular depression, upper-airway obstruction, apnea, and potential aspiration. Specialized training in Pediatric Advanced Life Saving (PALS) and equipping the dental operatory with the necessary rescue equipment and medications can save patient lives until advanced medical systems arrive (6).


1. Standard of Practice: use of sedation and general anesthesia in dental practice. [Analysis in brief on the Internet]. Toronto: The Royal College of Dental Surgeons of Ontario; 2015 [cited 2020 Dec 6]. 40 p. Available from:

2. Nelson TM, Zheng X. Pediatric dental sedation: challenges and opportunities. Clinical, Cosmetic and Investigational Dentistry [Internet]. 2015 Aug [cited 2020 Dec 29]; 7: 97-106. Available from:

3. Attri JP, Sharan R, Makkar V, Gupta KK, Khetarpal R, Kataria AP. Conscious Sedation: Emerging trends in Pediatric dentistry. Anesthesia Essays and Researches [Internet]. 2017 Apr-June [cited 2020 Dec 29]; 11(2): 277-281. Available from:

4. Gupta, PD, Mahajan P, Monga, P, Thaman D, Khinda VIS, Gupta A. Evaluation of the efficacy of nitrous oxide inhalation sedation on anxiety and pain levels of patients undergoing endodontic treatment in a vital tooth: a prospective randomized control trial. Journal of Conservative Dentistry [Internet]. 2019 July-Aug [cited 2020 Dec 29]; 22(4): 356-361. Available from:

5. Ozgul B, Haluk B, Isik B. Effectiveness of premedication agents administered prior to nitrous oxide/oxygen. European Journal of Anesthesia [Internet]. 2010 April [cited 2020 Dec 30]; 27(4): 341-346. Available from:

6. Cote CJ, Wilson S. Guidelines for Monitoring and Management of Pediatric Patients Before, During, and After Sedation for Diagnostic and Therapeutic Procedures. Pediatrics [Internet]. 2019 [cited 2020 Dec 30]; 143(6).

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