Home | About Us | Editorial Board | Current Issue | Archives | Search | Instructions | Subscription | Feedback | e-Alerts | Login 
Journal of Indian Society of Pedodontics and Preventive Dentistry Official publication of Indian Society of Pedodontics and Preventive Dentistry
 Users Online: 879  
 
  Print this page Email this page   Small font sizeDefault font sizeIncrease font size


 
  Table of Contents    
ORIGINAL ARTICLE
Year : 2015  |  Volume : 33  |  Issue : 3  |  Page : 239-244
 

Evaluation of nitrous oxide inhalation sedation during inferior alveolar block administration in children aged 7-10 years: A randomized control trial


1 Department of Paedodontics and Preventive Dentistry, Manipal University, Manipal College of Dental Sciences, Mangalore, Karnataka, India
2 Department of Public Health Dentistry, Manipal University, Manipal College of Dental Sciences, Mangalore, Karnataka, India

Date of Web Publication9-Jul-2015

Correspondence Address:
Dr. Arathi Rao
Department of Paedodontics and Preventive Dentistry, Manipal College of Dental Sciences, Manipal University, Light House Hill Road, Mangalore - 575 001, Karnataka
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0970-4388.160399

Rights and Permissions

 

   Abstract 

Background: Nitrous oxide-oxygen (N 2 O-O 2 ) is being used in combination with many drugs and this possess risk for leading to deep sedation or reflexes being compromised. Aim: The purpose of our study was to use N 2 O-O 2 alone, to evaluate its effectiveness for pain control during inferior alveolar nerve block administration in children. Design: This was a single-centered, simple randomized, double-blinded, placebo-controlled parallel-group study involving 40 children in the age group of 7-10 years divided into 2 groups: N 2 O-O 2 sedation and oxygen. Pain perception for local anesthesia was assessed using face, legs, activity, cry, consolability scale. Children's behavior was assessed using Frankl ratings, depth of sedation using Observer's Assessment of Alertness/Sedation scale. The vital signs and oxygen saturation were recorded. Results: There was a significantly lower pain reaction to local anesthetic administration in the N 2 O-O 2 group (P < 0.01). Improvement in the behavior of the children belonging to N 2 O-O 2 group during and after the procedure as compared to the O 2 group (P < 0.01) was also observed. All the vital signs recorded were in the normal physiologic limits in both the groups. Conclusion: Pain experienced by children receiving N 2 O-O 2 sedation was significantly lower. N 2 O-O 2 inhalation sedation produces adequate sedation with vital signs within normal limits and treatments successfully completed.


Keywords: Behavior, conscious sedation, nitrous oxide, pain


How to cite this article:
Takkar D, Rao A, Shenoy R, Rao A, Suprabha BS. Evaluation of nitrous oxide inhalation sedation during inferior alveolar block administration in children aged 7-10 years: A randomized control trial. J Indian Soc Pedod Prev Dent 2015;33:239-44

How to cite this URL:
Takkar D, Rao A, Shenoy R, Rao A, Suprabha BS. Evaluation of nitrous oxide inhalation sedation during inferior alveolar block administration in children aged 7-10 years: A randomized control trial. J Indian Soc Pedod Prev Dent [serial online] 2015 [cited 2019 Jul 17];33:239-44. Available from: http://www.jisppd.com/text.asp?2015/33/3/239/160399



   Introduction Top


Nonpharmacological behavior management techniques are routinely used and suffice to create an environment that facilitates the development of child's confidence and allows the dentist to carry out procedures with minimal disruption. However, in case of very fearful or anxious children, these techniques may not be sufficient and conscious sedation may prove to be a helpful tool. [1]

Use of pharmacological behavior management techniques such as nitrous oxide (N 2 O) conscious sedation coupled with local anesthesia when required forms the foundation of the delivery of pain-free dentistry to children. [2]

Nitrous oxide-oxygen (O2) was frequently used in combination with many drugs such as chloral hydrate, hydroxyzine, midazolam. The majority of the studies used N 2 O in combination with other agents to obtain the desired effects. [3],[4],[5],[6],[7],[8],[9] N 2 O when combined with other agents possess risk as the combination can have synergistic action and potential for central nervous system depression is magnified and lead to deep sedation or general anesthesia such as effect [10],[11],[12],[13] with reflexes being compromised.

Administration of local anesthesia often leads to high anxiety and unco-operative behavior in children. Nerve block anesthesia is known to be more painful and least accepted by children. The purpose of our study was to use N 2 O-O 2 alone to evaluate its effectiveness for pain control during inferior alveolar nerve block administration in children.


   Materials and Methods Top


This was a single-centered, simple randomized, double-blinded, placebo-controlled parallel-group study. Sample size was calculated with a power of 0.90 at 95% confidence level. Forty children in the age group of 7-10 years were selected after screening for inclusion and exclusion criteria for children attending for dental treatment in a pediatric dental department. The study was carried over a period of 6 months.

Inclusion criteria

The inclusion criteria were as follows: Dental treatment to be done under inferior nerve block anesthesia; subjects who belong to Frankl 2 and 3 rating during examination process; subjects belong to American Society of Anesthesiologists 1 category; written informed consent from the parents/guardians.

Exclusion criteria

Exclusion criteria were as follows: Clinical condition contraindicating the use of N 2 O-O 2 ; subjects with known allergy to lignocaine.

Ethical clearance

Ethical clearance was obtained from the Institutional Ethics Committee approval prior to the commencement of the study. Detailed information regarding the procedures, risk involved, etc. contained in the patient/information sheet was given to the parents, and all queries answered. After obtaining written informed consent from parents, verbal consent was taken from the children prior to the study.

Randomization

Subjects were randomly allocated into two Groups-A and B using the chit-pick box method. Group A (n = 20) were given N 2 O-O 2 sedation and Group B (n = 20) only oxygen as placebo. Twenty chits were made for each group and kept in a box. Each child was asked to pick a chit and accordingly he/she was allocated into the group.

Blinding

Three investigators were involved in the study:

  1. Administrator - Person administering sedation (N 2 O-O 2 and oxygen).
  2. Observer - Person monitoring the child and recording the scales and vital signs.
  3. Operator - Person who carried out the dental procedure.


The subject and the observer were blind to the agent used during the procedure. The child picked the chit and gave it to the administrator, who noted down the same in a separate log book. The observer was seated in such a manner that the N 2 O unit and display was not visible.

Sedation and treatment protocol

Preprocedural evaluation

Child's airway was assessed. Extra- and intra-oral physical examination were done. Before commencing the sedation process, child's behavior was again determined using Frankl scale. [14]. The vital signs (pulse, respiratory rate) and oxygen saturation were evaluated prior to the dental treatment.

Method

A compact, portable machine (Quantiflex MDM, USA) permitting continuous flow of N 2 O and oxygen, with monitored dial mixer for N 2 O-O 2 was used for the study. Well-fitted nonscented nasal hoods were used.

The technique [15],[16] was described to the patient as per the child's level of understanding using euphemisms. Group A: A flow rate (liter per minute) of 100% oxygen was established, and the nasal hood was secured on the patient's nose. The hood was adjusted suitably for child's comfort. The appropriate flow rate was established while the child was breathing 100% oxygen (5-6 l/min) for 1-2 min. Nasal breathing was encouraged, and the nasal hood was checked for leaks. The reservoir bag was monitored that it should remain uniform during breathing and should not expand or shrink. The percentage of N 2 O was started initially at 10%. Then, it was titrated in approximately 10% increment rise every 60 s. The N 2 O was titrated up to 30-40%. Constant communication with the child including physical, visual and verbal contact was maintained. Once the objective signs of sedation were observed (child became relaxed, spontaneous movements decreased, abduction of feet); the child was questioned how as to how he or she was feeling. When the child stated that he or she was feeling pleasant and relaxed, it was concluded that the ideal level of clinical sedation was achieved and the dental treatment was initiated. As the treatment ended and the need for sedation requirement ceased, the N 2 O flow was tapered and the child was given 100% oxygen at a flow rate equivalent to the established rate for him or her 3-5 min before terminating the sedation process to prevent diffusion hypoxia and allow complete recovery from sedation. The child was discharged if the presedation level of responsiveness or a level as close as possible to normal was achieved.

Group B: In the oxygen group, 100% oxygen was administered and appropriate flow rate was established as for the nitrous-oxide/oxygen group. After 5 min of administering oxygen, the procedure was initiated.

Local anesthesia administration

All the children selected for the study needed pulp therapy to be done under inferior alveolar nerve block. Children were explained regarding the procedure using euphemisms. Inferior alveolar nerve block was performed using the conventional technique after application of topical anesthesia. A volume of 1.5 ml of 2% lignocaine hydrochloride with 1:100,000 adrenaline (Neon, India) was used through a 30 gauge, 25 mm long needle. The rate of injection was standardized at 1 mm/min.

Data collection

The pain perception during and after administration of local anesthesia was assessed using face, legs, activity, cry, consolability (FLACC) [17] scale [Table 1] and [Table 2]. The child's behavior during and after administration of local anesthesia was recorded.
Table 1: FLACC behavioral pain assessment scale


Click here to view
Table 2: Interpretation of the FLACC scores


Click here to view


Monitoring

Once optimal sedation was obtained, the depth of sedation was assessed using Observer's Assessment of Alertness/Sedation (OAA/S) scale [18] [Table 3] and [Table 4]. The depth of sedation for the Group B was analyzed after administering oxygen for 5 min.
Table 3: OAA/S Scale


Click here to view
Table 4: Interpretation of the OAA/S Scale


Click here to view


The vital signs (pulse, respiratory rate), oxygen saturation were recorded every 3 min from the start of the sedation process to the end of local anesthesia administration. All the recordings were done for both the groups.

Statistical analysis

The obtained data were compiled systematically and analyzed using SPSS for Windows release 19.0 (SPSS Inc., Chicago, IL, USA). The level of significance was kept at P < 0.05. The analysis of the behavior rating, level of sedation and pain felt by children was done using Pearson Chi-square test.

The physiologic parameters-partial pressure of oxygen, heart rate and respiratory rate were evaluated using repeated measures of ANOVA.


   Results Top


Of 40 children involved in study, 24 (60%) were females, 16 (40%) were males. The duration of local anesthesia administration of ranged from 9 to 15 min depending on the behavior management and requirement of sedation for each child.

Baseline demographic and clinical characteristics are explained in [Table 5]. Behavior recording, OAA/S, FLACC scale and vital sign recordings during the procedure is given in [Table 6], [Table 7], [Table 8].
Table 5: Baseline demographic and clinical characteristics


Click here to view
Table 6: Behavior recording during and after administration of local anesthesia


Click here to view
Table 7: OAA/S and FLACC Scale scores during the procedure


Click here to view
Table 8: Average scores of the vital signs recorded during the procedure


Click here to view


Frankl behavior rating

Local anesthesia was administered successfully to all the children in both the groups. Chi-square test revealed that at baseline, there was no statistically significant difference between the groups (P = 0.204). However, there was a statistically significant difference in the behavior of children during and after the procedure in the two treatment groups (P < 0.01). Few children remained uncooperative till the end of the procedure but continued to hold the hood over the nose.

Level of discomfort/pain/both

The level of discomfort or pain was assessed using the FLACC scale. Significant difference was observed in the level of discomfort experienced by children between both the groups (P < 0.01).

Level of sedation

The level of alertness or sedation was evaluated using the OAA/S scale. In the N 2 O/O 2 group, 2 children were alert, 13 lightly sedated, and 5 were moderately sedated during the treatment. In the O 2 group, 19 children were alert and 1child appeared sedated. The difference was significant.

Vital signs and oxygen saturation

The values of all the physiologic parameters were in the normal clinical range throughout the sedation period. There was no statistically significant difference found in either of the groups as measured by the repeated measures of ANOVA. (P = 0.894, 0.774, 0.894 respectively for partial pressure of oxygen , heart rate, respiratory rate).


   Discussion Top


The present study examined the effect of N 2 O-O 2 on the behavior pattern, level of sedation attained and pain experienced by children during dental procedures. Children between 7 and 10 years of age were chosen for the study because at this age they can understand the verbal explanation given to them regarding enrollment to the study. Total of 16 males and 24 females subjects were part of the study. Gender is not known to influence subjective response to N 2 O sedation. [19]

All the children who participated in the study had not been exposed to N 2 O sedation earlier. This and allocation concealment shielded the participants from being influenced to the effects of past experience. Plain oxygen group was used as a placebo-controlled parallel design in the study. Cross over design was not chosen as this may influence the child's behavior. Administering inferior alveolar block was chosen as this procedure is found to be less tolerated in children compared to other dental procedures. About 90-95% of the children were co-operative (Frankl rating 3 or 4) during and at the end of local anesthesia administration.

In a clinical study by Houpt et al., [20] 100% of the children became cooperative exhibiting Frankl 3 or 4 rating. From the clinical standpoint, adequate improvement in children's behavior was observed in the present study with N 2 O-O 2 .

In the present study, Frankl behavior rating was used to assess the child's behavior. Frankl rating has been found to be efficient in clinical practice and revealed a direct relationship between the predicted behavior and the actual manifested behavior during dental appointments. [21]

Inadequate relief of procedural pain and distress affects the experience of children and their parents, and also adversely affects the procedural success. N 2 O analgesia works by anxiolysis that allows the patient to tolerate unpleasant procedures by reducing discomfort, thereby expediting the delivery of procedures. [5]

Pedersen et al. [22] reviewed the safety and efficacy of N 2 O and found it to be effective during brief, but mild to moderately painful pediatric procedures.

In our study, most of the children in N 2 O-O 2 group were relaxed (45%) or exhibited mild discomfort (45%) during local anesthesia administration.

Several studies in literature have used visual analog scale (VAS) which children rate their pain at the end of the procedure. However, owing to its subjective nature; this can be inconsistent in children especially after an episode of sedation. In the present study, the FLACC scale was thus used as it is observed by an independent observer. The FLACC behavioral pain tool has excellent reliability and validity in assessing pain in children. The scale has five criteria, which are each assigned a score of 0, 1 or 2. Each of the five categories (F) face; (L) legs; (A) activity; (C) cry; (C) consolability is scored from 0 to 2, which results in a total score between 0 and 10. [23]

The OAA/S scale used in the study is reliable and valid relative to the VAS. It is simple and quick to administer and requires little training. Thus, it is a useful tool in measuring the degree of sedation over time. Chernik et al. [18] found that depth of anesthesia is best assessed clinically and with OAA/S scale, which is reliable and valid.

Rampil et al. [24] evaluated the bispectral electroencephalogram (EEG) index during administration of N 2 O at several concentrations (10, 20, 30, 40, 50%) on 13 healthy adult volunteers. The spectral content of the EEG changed during administration of N 2 O, but not significantly affecting the index. No significant change in OAA/S scale was detected during the study. In the present study, 65% of the children were mildly sedated, 25% showed moderate sedation and 10% remained alert. The difference in the OAA/S score in the 2 studies could be in the difference in the age group of the subjects and OAA/S score that was recorded at different concentrations of N 2 O.

Pulse-oximetry was used to measure the oxygen saturation and the heart rate. No significant difference was found in either of the groups. All patients had oxygen saturation levels of more than 92% throughout their treatment. The heart rate reduced from baseline during administration of N 2 O-O 2 and thereafter but was well within the normal clinical range. This may be due to the anxiolytic effect of N 2 O. The heart rate that was within the clinical range in oxygen group may be due to the placebo effect. There was no change in the respiratory rate from baseline recording until the end of the observation period.

Most of the inhalation agents have a tendency to increase respiratory rate but decrease tidal volume and produce a dose-dependent reduction in mean arterial pressure. N 2 O is distinguished from other agents in that it does not reduce net ventilation or produce any change in arterial pressure. [25],[26] In the present study, also there was no much changes in the heart and respiratory rate and oxygen saturation.

No adverse events occurred in our study. The safety of this technique lies in the ability to titrate N 2 O to the desired concentration. N 2 O was delivered in the range of 30-40% for all the children and was adequate for successful completion of the procedure. The main factors that justify the use of N 2 O are its well-defined indications, the rapid onset of action and brief resolution of the effects in addition to the absence to any kind of nephrotoxicity, hepatotoxicity etc. [11],[27]

Many studies focus on the use of N 2 O-O 2 in combination with other agents justifying that the outcome is better. A study by Fukuta et al. [28] found better patient compliance to wear the nasal hood in children who were given N2O/O 2 subsequent to intranasal administration of midazolam. But in the present study, all the children accepted the hood after appropriate nonpharmacological behavior management technique.

It is also convinced in the present study that over 90% of children undergoing dental treatment under local anesthesia was completed successfully under sedation with N 2 O-O 2 sedation administered at 30-40%. N 2 O alone in suitable dose is found to be well-tolerated by pediatric patients, making it possible to perform treatments with mild anesthesia. [27] Higher dose of N 2 O may produce deep sedation or general anesthesia like effect [10],[11]

In the present study, assessment was done only during administering local anesthesia. The observation period could have been extended for the entire procedure to obtain a more consistent readings.

Reasons - why this paper is important to pediatric dentists.

  • Nitrous oxide-oxygen inhalation sedation when used alone also produces mild to moderate sedation to complete dental procedures in anxious children with all the vital signs within normal physiologic limits.
  • Pain experienced by children receiving N 2 O-O 2 sedation was significantly lower than children who received O 2 alone during the administration of local anesthesia with significant improvement in the behavior of children during and after the procedure.
  • Since the treatment scheduled for the appointment was completed in all children, the efficacy of N 2 O/O 2 or O 2 has been proven.


 
   References Top

1.
Folayan MO, Faponle A, Lamikanra A. Seminars on controversial issues. A review of the pharmacological approach to the management of dental anxiety in children. Int J Paediatr Dent 2002;12:347-54.  Back to cited text no. 1
    
2.
Hosey MT, UK National Clinical Guidelines in Pediatric Dentistry. UK National Clinical Guidelines in Paediatric Dentistry. Managing anxious children: The use of conscious sedation in paediatric dentistry. Int J Paediatr Dent 2002;12:359-72.  Back to cited text no. 2
    
3.
Houpt M. Project USAP the use of sedative agents in pediatric dentistry: 1991 update. Pediatr Dent 1993;15:36-40.  Back to cited text no. 3
    
4.
Houpt M. Report of project USAP: The use of sedative agents in pediatric dentistry. ASDC J Dent Child 1989;56:302-9.  Back to cited text no. 4
    
5.
Houpt MI, Sheskin RB, Koenigsberg SR, Desjardins PJ, Shey Z. Assessing chloral hydrate dosage for young children. ASDC J Dent Child 1985;52:364-9.  Back to cited text no. 5
    
6.
Houpt MI, Weiss NJ, Koenigsberg SR, Desjardins PJ. Comparison of chloral hydrate with and without promethazine in the sedation of young children. Pediatr Dent 1985;7:41-6.  Back to cited text no. 6
    
7.
Houpt MI, Rosivack RG, Rozenfarb N, Koenigsberg SR. Effects of nitrous oxide on chloral hydrate sedation of young children. Anesth Prog 1986;33:298-302.  Back to cited text no. 7
    
8.
Houpt M, Manetas C, Joshi A, Desjardins P. Effects of chloral hydrate on nitrous oxide sedation of children. Pediatr Dent 1989;11:26-9.  Back to cited text no. 8
    
9.
Baygin O, Bodur H, Isik B. Effectiveness of premedication agents administered prior to nitrous oxide/oxygen. Eur J Anaesthesiol 2010;27:341-6.  Back to cited text no. 9
    
10.
Becker DE, Rosenberg M. Nitrous oxide and the inhalation anesthetics. Anesth Prog 2008;55:124-30.  Back to cited text no. 10
    
11.
Myles PS, Leslie K, Silbert B, Paech MJ, Peyton P. A review of the risks and benefits of nitrous oxide in current anaesthetic practice. Anaesth Intensive Care 2004;32:165-72.  Back to cited text no. 11
    
12.
Langa H. Relative Analgesia in Dental Practice. 2 nd ed. Philadelphia, PA: Saunders; 1976.  Back to cited text no. 12
    
13.
Goodson JM, Moore PA. Life-threatening reactions after pedodontic sedation: An assessment of narcotic, local anesthetic, and antiemetic drug interaction. J Am Dent Assoc 1983;107:239-45.  Back to cited text no. 13
    
14.
Wright GZ. Behavior Management in Dentistry for Children. Philadelphia: WB Saunders Co.; 1975.  Back to cited text no. 14
    
15.
Clark MS. Contemporary issues surrounding nitrous oxide. In: Malamed SF, editor. Sedation: A Guide to Patient Management. 5 th ed. St. Louis, MO: Mosby Elsevier; 2010. p. 256.  Back to cited text no. 15
    
16.
Malamed SF, Clark MS. Nitrous oxide-oxygen: A new look at a very old technique. J Calif Dent Assoc 2003;31:397-403.  Back to cited text no. 16
    
17.
Merkel SI, Voepel-Lewis T, Shayevitz JR, Malviya S. The FLACC: A behavioral scale for scoring postoperative pain in young children. Pediatr Nurs 1997;23:293-7.  Back to cited text no. 17
    
18.
Chernik DA, Gillings D, Laine H, Hendler J, Silver JM, Davidson AB, et al. Validity and reliability of the Observer′s Assessment of Alertness/Sedation Scale: Study with intravenous midazolam. J Clin Psychopharmacol 1990;10:244-51.  Back to cited text no. 18
    
19.
Zacny JP, Jun JM. Lack of sex differences to the subjective effects of nitrous oxide in healthy volunteers. Drug Alcohol Depend 2010;112:251-4.  Back to cited text no. 19
    
20.
Houpt MI, Limb R, Livingston RL. Clinical effects of nitrous oxide conscious sedation in children. Pediatr Dent 2004; 26:29-36.  Back to cited text no. 20
    
21.
Bankole OO, Denloye OO, Aderinokun GA, Jeboda SO. The relationship of childrens predicted behaviour to their observed behaviour during dental procedures. Afr J Biomed Res 2002;5:109-13.  Back to cited text no. 21
    
22.
Pedersen RS, Bayat A, Steen NP, Jacobsson ML. Nitrous oxide provides safe and effective analgesia for minor paediatric procedures - A systematic review. Dan Med J 2013;60:A4627.  Back to cited text no. 22
    
23.
Voepel-Lewis T, Zanotti J, Dammeyer JA, Merkel S. Reliability and validity of the face, legs, activity, cry, consolability behavioral tool in assessing acute pain in critically ill patients. Am J Crit Care 2010;19:55-61.  Back to cited text no. 23
    
24.
Rampil IJ, Kim JS, Lenhardt R, Negishi C, Sessler DI. Bispectral EEG index during nitrous oxide administration. Anesthesiology 1998;89:671-7.  Back to cited text no. 24
    
25.
Dahan A, van den Elsen MJ, Berkenbosch A, DeGoede J, Olievier IC, van Kleef JW, et al. Effects of subanesthetic halothane on the ventilatory responses to hypercapnia and acute hypoxia in healthy volunteers. Anesthesiology 1994;80:727-38.  Back to cited text no. 25
    
26.
Eger EI, editor. Respiratory effects of nitrous oxide. In: Nitrous Oxide. New York: Elsevier; 1985.  Back to cited text no. 26
    
27.
Duarte LT, Duval Neto GF, Mendes FF. Nitrous oxide use in children. Rev Bras Anestesiol 2012;62:451-67.  Back to cited text no. 27
    
28.
Fukuta O, Braham RL, Yanase H, Kurosu K. The sedative effects of intranasal midazolam administration in the dental treatment of patients with mental disabilities. Part 2: Optimal concentration of intranasal midazolam. J Clin Pediatr Dent 1994;18:259-65.  Back to cited text no. 28
    



 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]



 

Top
Print this article  Email this article
 

    

 
  Search
 
  
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Article in PDF (322 KB)
    Citation Manager
    Access Statistics
    Reader Comments
    Email Alert *
    Add to My List *
* Registration required (free)  


    Abstract
   Introduction
    Materials and Me...
   Results
   Discussion
    References
    Article Tables

 Article Access Statistics
    Viewed2871    
    Printed68    
    Emailed3    
    PDF Downloaded311    
    Comments [Add]    

Recommend this journal


Contact us | Sitemap | Advertise | What's New | Copyright and Disclaimer 
  2005 - Journal of Indian Society of Pedodontics and Preventive Dentistry | Published by Wolters Kluwer - Medknow 
Online since 1st May '05