Nitrous oxide–oxygen inhalation for outpatient otologic examination and minor procedures performed on the uncooperative child

doi:10.1016/j.ijporl.2004.10.016

International Journal of Pediatric Otorhinolaryngology

Volume 69, Issue 4, April 2005, Pages 501-504

https://doi.org/10.1016/j.ijporl.2004.10.016 Get rights and content

Summary

Objective:

Otomicroscopic examination with suctioning of ears or other procedures is frequently uncomfortable especially for children. Anxiety and pain with lack of cooperation may result in trauma to the ear, incompletion of the examination, delayed diagnosis and treatment and need for completion of the examination under general anesthesia. The purpose of this study was to evaluate the efficacy and safety of utilizing nitrous oxide–oxygen inhalation for sedation and analgesia in otologic examination and minor surgical procedures performed on the uncooperative child at the outpatient clinic.

Methods:

In a prospective pilot case series study conducted at the Pediatric Otolaryngology outpatient clinic of a tertiary medical center, nitrous oxide–oxygen inhalation was administered by the examining otolaryngologist and the assisting nurse. The study group included children over 2 years old, for which an accurate diagnosis of ear pathology could not be made or a minor surgical procedure could not be tolerated because of anxiety and lack of cooperation.

Results:

Completion of the indicated procedure was successful in 21 of 24 patients (88%). Full cooperation, where no restraint was necessary was achieved in 20 of 24 patients (83%). The mean rank pain scores, evaluated separately by the patient, parent and staff, were in the mild pain range using a 0–10 coding for Faces Pain Rating Scale. The mean procedure time was 8.9 min. An adverse reaction, vomiting, occurred in one patient. Twenty-one of 24 parents stated that they would repeat the procedure if necessary.

Conclusion:

This pilot study shows the potential usefulness of nitrous oxide–oxygen inhalation administered by an otolaryngologist in the outpatient clinic. Alleviation of pain and anxiety and avoiding the need for physical restraint is an important goal that can be achieved with this form of sedation.

Introduction

Although nitrous oxide has been commonly used for dental office procedures [1], in hospital wards [2] and in a variety of other procedures in children [3], [4], it has not been evaluated in the pediatric otolaryngology outpatient clinic. This fact and the reported long lasting psychological effects of pain in children [5] underlined the basis for our study.

Section snippets

Methods

Children over 2 years old, for which an accurate diagnosis of ear pathology could not be made or a minor surgical procedure could not be tolerated because of anxiety and lack of cooperation, were included in the study. Nitrous oxide–oxygen inhalation before and during the otologic examination or procedure was administered by the examining otolaryngologist and the assisting nurse. A second physician (a dentist with previous experience with nitrous procedures) was present to assist. Nitrous

Results

Twenty-four children were included in the study. Male to female ratio was 1:1. Mean age was 6.4 years (range 2–12). Table 1 shows the distribution of the indications. Mean total inhalation time was 8.9 + −5.5 min. The mean induction inhalation time was 3.0 + −1.3 min. The mean rank pain scores, evaluated separately by the patient, parent and staff, were in the mild pain range on a 0–10 Faces Pain Rating Scale. Parents underestimated pain but not statistically significant. Fig. 1 summarizes the pain

Discussion

Since introduced by Tunstall in 1961 [8] the use of a fixed mixture of nitrous oxide and oxygen for alleviation of pain has spread to a variety of hospital settings. It is especially common in dental practice. An impressive French survey shows the usefulness of nitrous oxide–oxygen mixture in a variety of procedures with successful results and without serious side effects [9].

To our knowledge this is the first study for evaluation of the use of nitrous oxide in the outpatient otolaryngology

References (12)

M.E. Tunstall
The use of a fixed nitous oxide and oxygen mixture from one cylinder
Lancet
(1961)
G.J. Roberts
Inhalation sedation (relative analgesia) with oxygen/nitrous oxide gas mixturesI. Principles
Dent. Update
(1990)
L. Hirskyj
Use of Entonox in a general hospital
Nurs. Times
(1971)
W.L. Hennrikus et al.
Self-administered nitrous oxide analgesia for pediatric fracture reductions
J. Pediatr. Orthop.
(1994)
J.D. Luhmann et al.
Continuous-flow delivery of nitrous oxide and oxygen: a safe and cost-effective technique for inhalation analgesis and sedation of pediatric patients
Pediatr. Emerg. Care
(1999)
M.E. Taddio et al.
Effect of neonatal circumcision on pain response during subsequent routine vaccination
Lancet
(1997)

There are more references available in the full text version of this article.

Cited by (14)

Effectiveness of nitrous oxide sedation for otolaryngologic examination in the outpatient clinic in uncooperative children
2022, International Journal of Pediatric Otorhinolaryngology
Citation Excerpt :
Especially in children with developmental delay it may be challenging to perform a complete ENT examination. The use of nitrous oxide as conscious sedation for this purpose can reduce pain and anxiety and therefore facilitate clinical examination [4]. The implementation of nitrous oxide sedation in children undergoing dental procedures is already commonly accepted, but today there is little evidence supporting its application in paediatric otolaryngology.
The aim of this study is to investigate the efficacy of equimolar mixture of 50% nitrous oxide and oxygen (EMONO) to obtain conscious sedation for otolaryngologic examinations and minor Ear-Nose-Throat (ENT) procedures in children with or without comorbidities.
Retrospective analysis of patient records from all children who were uncooperative during routine ENT examination, and therefore underwent otomicroscopic examinations and/or minor ENT procedures sedated with EMONO in the outpatient ENT clinic. The following data were collected: patients characteristics, sedative effect, analgesic effect and adverse effects. Patients were divided into three subgroups: 1) no relevant comorbidities, 2) Down Syndrome and 3) other causes of behavioural problems or developmental delay.
Data were analyzed for 99 patients (170 procedures). Seven procedures failed. A good to excellent sedative and analgesic effect was obtained in most patients without a difference between subgroups. Minor and transient side effects were encountered in one third (34%) of the patients.
EMONO is an effective agent to achieve conscious sedation and to perform ENT examinations or minor procedures in otherwise uncooperative children with or without developmental delay.
Nitrous Oxide Use in Children
2012, Revista Brasileira de Anestesiologia
Evaluation of analgesic protocol with nitrous oxide and EMLA cream during botulinum toxin injections in children
2007, Annales de Readaptation et de Medecine Physique
Évaluer l'efficacité et la tolérance de l'analgésie par le protoxyde d'azote au cours des injections de toxine botulique dans le traitement de la spasticité focale chez l'enfant.
Étude prospective incluant 40 enfants, pour la plupart infirmes moteurs cérébraux (IMC), âgés de 2 à 17 ans et ayant reçu des injections de toxine botulique. Dix enfants étaient polyhandicapés. Le traitement concernait souvent plusieurs muscles, avec plusieurs injections par muscle. Le nombre total d'injections variait de 1 à 25. La procédure associait une anesthésie locale par crème EMLA et l'inhalation d'un mélange équimolaire de protoxyde d'azote et d'oxygène (MEOPA). Les manifestations douloureuses étaient évaluées par l'équipe (un médecin, un interne, une infirmière et une auxiliaire puéricultrice) comme présentes ou absentes, et directement reliées à l'injection ou non.
Quarante-cinq pour cent des patients n'ont présenté aucune manifestation douloureuse. Trente pour cent ont présenté des manifestations cliniques paraissant directement liées aux injections. Pour 25 %, il existait des manifestations non spécifiques et globalement imputables à de l'anxiété et de l'inconfort. Des effets secondaires modérés et réversibles ont été notés chez trois patients.
L'efficacité du MEOPA a été démontrée, à la fois sur la douleur et l'anxiété. Toutefois, on constate que son effet est insuffisant chez la moitié des patients inclus dans cette étude, et demande à reconsidérer ce protocole dans certains cas. L'évaluation précise de la douleur aiguë est difficile chez l'enfant avec un déficit cognitif. Les manifestations cliniques évocatrices de douleur peuvent aussi s'intégrer à de l'anxiété et à du stress.
To evaluate the efficiency and tolerance of analgesic treatment with nitrous oxide and topical eutectic mixture of local anesthetics (EMLA) in children undergoing botulinum toxin injections for focal spasticity.
Prospective study including 40 consecutive patients aged 2 to 17 years, most with cerebral palsy, undergoing botulinum toxin injections. Ten had severe cerebral palsy with cognitive deficiency. For most patients the treatment involved several muscles, with several injections per muscle. The total number of injections varied from 1 to 25. The procedure was performed with topical anesthesia with EMLA and inhalation of nitrous oxide (50% nitrous oxide, 50% oxygen). Reactions were recorded by the staff (a practician, a nurse, an auxiliary staff member and an internist) and whether they related to the injection or were nonspecific.
A total of 45% of patients showed no clinical manifestation of pain; for 30%, reactions were crying and withdrawal directly related to the injections; and for 25%, manifestations seemed nonspecific and mainly related to overall anxiety and discomfort. In 3 patients, moderate side effects were observed (visual hallucinations and euphoria).
Nitrous oxide analgesic with topical EMLA was efficient for children undergoing botulinum toxin injections but remained insufficient for half of our patients, and modification of the protocol is needed in some cases. Precise evaluation of acute pain is difficult in children with major cognitive deficits. Clinical manifestations are related to pain but also to overall anxiety and stress.
What are the current indications of MEOPA in children: How to use it?
2006, Praticien en Anesthesie Reanimation
Recent pharmacological advances in paediatric analgesics
2006, Biomedicine and Pharmacotherapy
Citation Excerpt :
Sedative drugs such as the benzodiazepines have variable effect and may result in loss of protective airway reflexes. The rapid onset and offset of nitrous oxide make this gas an attractive alternative [90–92]. It has been argued that nitrous oxide, when inhaled at levels below 50% maintains protective reflexes and does not require fasting or post procedure monitoring [91].
Growth and development are two linked processes that distinguish children from adults. The use of size as the primary covariate during pharmacokinetic (PK) analyses allows exploration of the effects of age. Allometric scaling models have assisted understanding of the developmental clearance changes in common analgesic drugs such as paracetamol, morphine, tramadol and local anaesthetics agents. Single nucleotide polymorphisms (pharmacogenomics [PG]) and their impact on hepatic drug metabolism for opioids, tramadol, non-steroidal anti-inflammatory drugs (NSAIDs) and drug receptor responses are increasingly reported. Altered chemical structure or formulations of common analgesics alter pharmacodynamic (PD) effects enhancing safety and efficacy for NSAIDs by stereoselectivity and the addition of nitric oxide, for intravenous paracetamol by formulation and structural difference from propacetamol and for local anaesthetics through stereoselectivity. This article focuses upon recent data for analgesics used in paediatric pain management including paracetamol, NSAIDs, morphine, tramadol, amide local anaesthetics and ketamine. It centres on PK and clinical studies in neonates, infants and children. PG studies are acknowledged as potentially allowing individual drug therapy tailoring through a decrease in between-patient population variability, although the impact of PG in the very young is less certain. There are few data describing age-related PD changes in children despite recognition that the number, affinity and type of receptors or the availability of natural ligands changes with age.
Case-series of nurse-administered nitrous oxide for urinary catheterization in children
2007, Anesthesia and Analgesia
Children undergoing urologic imaging studies requiring urethral catheterization experience considerable discomfort and psychological distress. Nitrous oxide sedation may mitigate these detriments but the requirement for physician administration has limited the applicability of this technique.
Registered nurses underwent the nitrous oxide training requirements prescribed for state licensure of dentists and dental hygienists, with special emphasis on pediatric sedation principles. To evaluate the safety of nurse-administered nitrous oxide, we consecutively enrolled all children (ASA PS I–II) sedated for urethral catheterization for urologic imaging in an observational trial designed to identify sedation-related adverse events.
Nitrous oxide was administered on 1018 occasions. There were no major adverse events (apnea, oxygen saturation <92%). Minor adverse events (diaphoresis, nausea, vomiting) occurred in 4% of patients. Eight patients (1%) were described as over-sedated. In 11 (1%) patients, nitrous oxide provided insufficient sedation for completion of urologic imaging.
Nitrous oxide sedation can be provided by a nurse-administered program in pediatric radiology. Administration of nitrous oxide for pediatric procedures by adequately trained nursing staff with appropriate multidisciplinary oversight may increase children’s access to this sedative/analgesic drug.

View all citing articles on Scopus

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Nitrous oxide–oxygen inhalation for outpatient otologic examination and minor procedures performed on the uncooperative child

Summary

Objective:

Methods:

Results:

Conclusion:

Introduction

Section snippets

Methods

Results

Discussion

Lancet

Inhalation sedation (relative analgesia) with oxygen/nitrous oxide gas mixturesI. Principles

Dent. Update

Use of Entonox in a general hospital

Nurs. Times

Self-administered nitrous oxide analgesia for pediatric fracture reductions

J. Pediatr. Orthop.

Continuous-flow delivery of nitrous oxide and oxygen: a safe and cost-effective technique for inhalation analgesis and sedation of pediatric patients

Pediatr. Emerg. Care

Effect of neonatal circumcision on pain response during subsequent routine vaccination

Lancet