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Title Nitrous Oxide Is Unlikely to Effectively Suppress the Gag Reflex in Severe Gaggers
Clinical Question In patients with a strong gag reflex, does nitrous oxide prevent gagging more effectively than distraction techniques?
Clinical Bottom Line Management of a strong gag reflex is likely to require moderate to deep sedation. It is unlikely that nitrous oxide or distraction techniques, either alone or in combination, would be beneficial for these patients.
Best Evidence (you may view more info by clicking on the PubMed ID link)
PubMed ID Author / Year Patient Group Study type
(level of evidence)
#1) 23231041Saita/2012 110 patients; age 16-75Prospective Cohort Study
Key resultsPatients were categorized into five grades using the Classification of Gagging Problem (CGP) index based on their severity of gagging with examination of the molar region. Management of these patients progressed based on response to treatment from M1 (management without anesthetics), M2 (moderate sedation), to M3 (deep sedation or general anesthesia) with a goal of desensitization in the lowest stage possible. Desensitization was successful in 38 patients. A majority of those who achieved desensitization were in M1 (70.8%), but those with higher-severity gag reflexes achieved low rates of desensitization (only 7.1% of M2 patients and 6.5% of M3 patients) (P<0.01). This study concluded that M1 (mild group), which mostly included patients in G1 or G2 (based on CGP), could be treated using distraction techniques and other various non-sedative methods. Patients classified in M2 or M3 (G3, G4, G5) had challenges in being desensitized, and sedation or even general anesthesia was necessary to complete dental treatment(P<0.01).
#2) 3166352Kaufman/1988 26 adults (ages 21-45) Controlled double-blinded clinical trial
Key resultsIn this study, the palatal and pharyngeal region was stimulated with a cotton swab, measuring the initial spot where the gagging response was initiated. Three experimental conditions were used on each patient using a nasal inhaler in each condition. The first condition measured baseline distance of the gag response with only room air. In the second condition, patients were administered 50% nitrous oxide (N2O)/50% oxygen (O2), and in the third condition, 80% N2O /20% O2 was administered. The results are as follows: baseline: 78.6 ± 8.6 mm; 80% N2O/20% O2: 80.8 ± 8.0 mm; 50% N2O/50% O2 88.0 ± 6.6 mm. The results show that tolerance of stimulation occurred further in the oropharyngeal region in the presence of nitrous oxide, indicating that nitrous oxide is effective at suppressing the gag reflex (P<0.005).
Evidence Search experimental[All Fields] AND study[All Fields] AND ("prevention and control"[Subheading] OR ("prevention"[All Fields] AND "control"[All Fields]) OR "prevention and control"[All Fields] OR "control"[All Fields] OR "control groups"[MeSH Terms] OR ("control"[All Fields] AND "groups"[All Fields]) OR "control groups"[All Fields]) AND ("gagging"[MeSH Terms] OR "gagging"[All Fields] OR ("gag"[All Fields] AND "reflex"[All Fields]) OR "gag reflex"[All Fields]) AND ("nitrous oxide"[MeSH Terms] OR ("nitrous"[All Fields] AND "oxide"[All Fields]) OR "nitrous oxide"[All Fields]) relationship[Title] AND gagging[Title] AND severity[Title] AND management[Title] AND dentistry[Title]
Comments on
The Evidence
Validity: In the Saita study, the dentists who performed dental treatment were not part of the evaluation of the patient’s CGP, but the study does not say if they were blinded. Only two patients withdrew from the study. All the patients in this trial complained of difficulty with dental treatment, so the patient population was not randomized. It also did not specify the method of sedation used, but that more extensive sedative measures were needed as the severity of the patient’s gag reflex increased. The Kaufman study was a three-way crossover trial in which all subjects received room air and both concentrations of N2O. The trial was not performed on patients who reported to be gaggers; they were patients who reported to have a normal gag reflex. The writer indicated that this study should be performed again with patients who have a severe gag response. Perspective: A randomized controlled trial of non-gaggers and gaggers of varying severity, using distraction and pharmacologic (nitrous oxide, oral sedatives, etc.) techniques, are needed to provide better evidence on the most effective methods to reduce gagging.
Applicability Many patients avoid dental care due to a combination of dental anxiety and a sensitive gag reflex. In the Saita study, some of the patients avoided dental treatment for years due to their gag response. The cause of the gag reflex also needs to be considered, as components of both psychological and somatogenic factors exist. Desensitization techniques may prove beneficial in treating patients with a strong gag reflex for more long lasting results, but this method may take more time and several appointments and may not be cost beneficial to the patient. Desensitization techniques may be necessary for denture patients, in whom nitrous oxide is not a feasible management approach. Overall, however, nitrous oxide is applicable in most dental settings for patients with a milder gag reflex, as it would allow for a more comfortable experience for both the clinician and the patient. For patients with a strong gag reflex, a management approach combining more than one method (e.g., nitrous and distraction) or a deeper level of sedation may be required to achieve results.
Specialty/Discipline (General Dentistry) (Oral Surgery) (Pediatric Dentistry)
Keywords Gag reflex, Gag response, Nitrous oxide, Distraction techniques, Desensitization
ID# 3199
Date of submission: 04/04/2017spacer
E-mail garciar22@livemail.uthscsa.edu
Author Rebeca Garcia
Co-author(s) e-mail
Faculty mentor/Co-author Kelly C. Lemke, DDS
Faculty mentor/Co-author e-mail LemkeK@uthscsa.edu
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