Physiological and Behavioral Manifestations of Nitrous Oxide in Pediatric Dentistry

• Author / Creator

  Moharrami, Mohammad

• Background: Nitrous oxide (N2O) is a common anesthetic drug used for distress management and improving the cooperation of children in dentistry. In clinical settings where it is used for moderate sedation and analgesia, the effect of N2O is mostly perceived as a single action through subjectively observing a child’s behavior during a procedure. This can be misleading since N2O can also have physiological manifestations such as the impact on vital signs as well. Moreover, since moderate sedation limits children's behavioral and communication abilities, the emotions of children are often not appreciated.
  Objectives: This study’s primary objective was to evaluate and predict the pediatric dental patients’ behaviors and vital signs undergoing N2O and to investigate whether and how behaviors can be predicted from vital signs and vice versa. The secondary objective was to evaluate the effect of age, sex, treatment duration, pre-existing anxiety, and parenting styles on vital signs and behaviors.
  Methods: Patients were consecutively recruited from a private dental clinic for this observational study using a within-subject design. All participants received 40% N2O/O2 inhalation gas and underwent non-surgical dental procedures. The dental procedure was divided into five different time points namely T1: before administration of N2O, T2: after administration of N2O, T3: dental injection, T4: dental treatment, and T5: discontinuation of N2O and administration of 100% O2. The primary outcome measure of the study was vital signs including pulse rate (PR), respiratory rate (RR), and oxygen saturation (SpO2). The PR and SpO2 were measured using a digital pulse oximeter while RR was measured by counting the number of deflations of the N2O reservoir bag. The secondary outcome measure, behavior of children, was scored using the Frankl scale through direct observation by a research assistant. Caregivers/parents completed validated questionnaires, including the short version of the Parenting Style and Dimension Questionnaire (PSDQ-32) and the Spence Children Anxiety Scale (SCAS), which were used to measure the parenting style and anxiety, respectively. The demographic information of participants was also collected via a separate questionnaire. The data were analyzed using repeated-measure ANOVA, Friedman test, multiple linear and ordinal regressions as well as general equation estimation (GEE) model at α=0.05.
  Results: Eighty children with the age range of 2 to 12 years and a mean age of 7.20±2.20 participated in this study. Our results showed that N2O significantly decreased PR (78.05±8.90 vs. 75.74±8.60), increased RR (22.68±3.52 vs. 23.88±3.07), and improved definitely-positive behaviors (77.5% vs. 57.5%), but did not change SpO2 (97.41±1.28 vs. 97.48±1.28) meaningfully. There was no interaction between the gas effect and predictors of the study including age, sex, parenting style, anxiety, and treatment duration. The dental injection significantly increased PR (80.13±9.73 vs. 75.74) and worsened the definitely-positive behaviors (55.0% vs. 77.5%) but did not affect RR and SpO2. Also, the dental treatment itself did not change behaviors and vital signs significantly. Transitioning from 40% N2O/O2 to 100% O2 after finishing the dental treatment did not change behaviors or vital signs. Child age was inversely associated with PR (B=-1.38, P=0.002) and RR (B=-0.26, P=0.003), and the authoritative parenting style predicted cooperative behaviors (odds ratio [OR]=1.93, P=0.01); other predictors were not significant. The higher PR in T2 predicted the poor behavior in T4 (OR=0.65, P=0.006); otherwise, there was no real-time association between vital signs and behaviors.
  Conclusion: The results suggested that using N2O can be considered safe and clinically acceptable by observing only minimal fluctuations in the measured vital signs. Improved cooperation and less distress were seen after the administration of N2O. During the dental procedure, dental injection seemed to lead to the highest fluctuations in vital signs and worst behaviors. The possible effect of N2O was not dependent on the predictors of the study meaning that N2O can have an impact on vital signs and behaviors regardless of the participants' demographics, degree of anxiety, parenting style, and treatment duration. Vital signs could not be predicted from behaviors, highlighting that the emotions of children cannot be understood by just observing the behaviors.

• Subjects / Keywords

  • nitrous oxide
  • vita signs
  • behaviors
  • emotions

• Graduation date

  Fall 2020

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-d9dt-cb72

• License

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