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SEDATION AND LARYNGOSPASM IN PEDIATRIC SURGERY: A
SYSTEMATIC REVIEW
Rebeca Alves Bezerra Bezerra1
Jullyanne Ester Silva Damasceno2
Natália Ferreira de Farias3
Milena da Nóbrega Dias4
1 Medicine by the University Center of João Pessoa
2 Medicine by the University Center of João Pessoa
3 Medicine by the University Center of João Pessoa
4 Medicine by the Faculty of Medicine Nova Esperança (Famene)
Abstract: Introduction: The use of anesthetics in pediatrics is essential for diagnostic and therapeutic
procedures. The incidence of post-anesthetic respiratory complications is often avoidable with
appropriate intervention. Laryngospasm, a reex obstruction of the vocal cords, is more common in
children. Objective: To discuss respiratory complications, with an emphasis on laryngospasm, during
the use of anesthetics in pediatric procedures. Method: The Medical Literature Analysis and Retrieval
System Online (MEDLINE, via PUBMED), Latin American and Caribbean Health Sciences Literature
(LILACS), Scientic Electronic Library Online (SciELO), and Virtual Health Library (VHL) databases
were used. Seven articles were selected that met the systematic review criteria. Results: The incidence
of laryngospasm is 0.87% in adults, 1.7% in children, and 2.82% in babies. In children, it occurs mainly
during emergence from anesthesia. Risk factors include inadequate anesthesia, respiratory infections and
multiple attempts at airway management. Drug combinations such as propofol, ketamine and fentanyl
are used to minimize complications. Preventive measures include clearing secretions and adequate
depth of anesthesia. Drugs such β2-adrenergic agonists, such as albuterol, are used to reduce respiratory
resistance during intubation. Training strategies with low-cost simulators are eective for managing
dicult airways in pediatrics. In pediatric surgery, the laryngeal mask is preferred to endotracheal
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intubation to reduce respiratory complications. Studies indicate that positive communication between
anesthesia teams improves performance in critical situations. Conclusion: Laryngospasm is a serious
complication in pediatric anesthesia, more common in children due to their anatomy and sensitive
reexes. Risk factors include respiratory infections, asthma, smoking, gastroesophageal reux, and
supercial anesthesia. Prevention involves the proper use of anesthetics, cleaning secretions and careful
monitoring. Medications such as propofol, ketamine, and albuterol can reduce adverse eects. Simulator
training and eective communication in anesthesia teams improve clinical performance. With proper
management, most episodes are resolved without long-term complications.
Keywords: pediatric anesthesia. laryngospasms. hypnotics and sedatives
Introduction
The need for anesthetics in pediatrics goes beyond their use in the operating room. Moderate
to intense sedation or even general anesthesia in children helps them to withstand diagnostic procedures
or medical treatments (Hayes et al., 2020). In addition, the morbidity and mortality associated with
pediatric anesthesia have fallen dramatically in the last 10 years (Tolosa et al., 2021). However, among
the risks of sedoanalgesia in the pediatric age group, respiratory complications are the most feared,
due to the high systemic demand for oxygen consumption and the low physiological reserve of the age
group, easily predisposing to the occurrence of respiratory complications during induction of anesthesia
(Liu et al., 2021).
Despite the advances made, post-anesthetic respiratory complications continue to be a concern
due to their high frequency. In pediatrics, the incidence of signicant complications is over 5.2%, and
a considerable proportion of these cases could be avoided if there were adequate intervention by the
professionals responsible (Tolosa et al., 2021). Studies show that more than half of patients undergoing
an upper airway approach have at least one identiable risk factor. It is therefore extremely important
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that the preoperative assessment includes risk factors such as obstructive sleep apnea, respiratory tract
infections in the last two weeks, partially controlled asthma or wheezing episodes three or more times
in the last twelve months, wheezing and dyspnea on exercise, persistent nocturnal cough, a history of
eczema, exposure to smoking, and a family history of asthma (von Ungern-Sternberg et al., 2019).
Tracheal intubation is a routine practice in pediatric anesthesia; however, despite advances in
approaches and protocols, this procedure still represents one of the main causes of morbidity in children
due to its physiological characteristics, which favor a rapid progression to hypoxia during apnea. Possible
complications such as desaturation, laryngospasm, coughing, bronchospasm, and hypoxia, among
others, can occur both during induction and during post-anesthetic recovery (Arican et al., 2021). These
adverse events vary in severity, from minor problems such as desaturation (blood oxygenation of less
than 95%) and upper airway obstruction (obstruction of the airway leading to snoring and respiratory
discomfort) to more serious complications such as laryngospasm (complete obstruction of the airway
associated with abdominal and thoracic muscle rigidity) and bronchospasm (increased respiratory eort,
particularly during expiration, leading to wheezing on auscultation), which is even more prevalent in
surgical procedures involving the airway (von Ungern-Sternberg et al., 2019).
Laryngospasm can occur at any stage of anesthetic preparation and usually manifests with the
sign of inspiratory stridor that can progress to complete obstruction, increased respiratory eort, tracheal
tugging, paradoxical respiratory eort, oxygen desaturation with or without bradycardia, and airway
obstruction that does not respond to a supraglottic airway (Gavel and Walker, 2014). Laryngospasm
occurs more commonly in pediatric anesthetic practices than in adults.
To optimize anesthetic management and reduce the risk of adverse events, various approaches
are adopted, as discussed by Von Ungern-Sternberg et al. This includes the use of devices such as the
laryngeal mask and dierent venous induction techniques with a variety of drugs. Among the agents
used are propofol, opioids, benzodiazepines, ketamine, and dexmedetomidine, alone or in combination,
each of which has its own risks and side eects and should be thoroughly analyzed by the anesthetic
team before administration.
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Therefore, it is important to identify early the risk factors that favor the onset of respiratory
complications, in addition to considering the experience of the anesthesiologist, since the incidence
of laryngospasm is higher among professionals with less experience (Lejus-Bourdeau et al., 2021). A
systematic review is needed to assess the prevalence, risk factors, consequences, and management and
prevention strategies for laryngospasm in children undergoing surgery. In addition, to evaluate the
records of complications and clinical outcomes associated with physical and psychological impacts
in pediatric patients, as well as to investigate early diagnostic techniques and signs that anticipate
respiratory complications or therapeutic interventions for management, including considering both
pharmacological and non-pharmacological approaches that may inuence the outcome of the event.
It is necessary to investigate the precautionary measures that identify the sedatives and
procedures that are most prone to laryngospasm and the risk factors for the development of this
complication and the perioperative practices that are eective in preventing this event after the use of
sedatives in children. These risks make it necessary to constantly evolve and re-evaluate anesthetic
approaches in pediatrics in order to increase the percentage of successful procedures during the
perioperative period (von Ungern-Sternberg et al., 2019). The main objective of this article is to discuss
respiratory complications, with an emphasis on laryngospasm, during the use of anesthetics in pediatric
procedures.
Methods
In this systematic review, the following articles were considered eligible: (1) they were related
to sedation and the occurrence of laryngospasm in pediatric surgeries; (2) they described pediatric
surgeries and the risks associated with dierent types of sedatives; (3) they included the denition of
laryngospasm in the pediatric context. It is limited to studies whose population is pediatric patients,
with exposure to anesthetics with the outcome of laryngospasm.
Exclusion criteria included those that discussed the occurrence of laryngospasm in adults, as
well as studies with samples not carried out on human beings, incomplete texts, duplicates, and texts not
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in Portuguese, English, or Spanish.
A remote search was carried out on the available electronic platforms, using the Medical
Literature Analysis and Retrieval System Online (MEDLINE, via PUBMED), Latin American and
Caribbean Health Sciences Literature (LILACS), Scientic Electronic Library Online (SciELO), and
Virtual Health Library (VHL) databases. The information for this study was obtained and collected by
both researchers between May and August 2024, under the recommendations of the Preferred Reporting
Items for Systematic Reviews and Meta-Analysis (PRISMA 2020) protocol.
A time limit was set, covering articles published between 2019 and 2024. The search strategy
used covered articles written in Portuguese, English, and Spanish, with free availability of full text
among clinical studies and randomized clinical trials. The articles were found using the Medical Subject
Heading (MeSH) descriptors: “pediatric anesthesia”, “laryngospasms” and “hypnotics and sedatives”.
The keywords used for the search process in English were: Pediatric Anesthesia OR Laryngospasms
OR Hypnotics and Sedatives.
The selected quotes were studied and reviewed entirely by the two researchers independently
in order to extract the necessary information about the importance of pediatric surgeries and the
challenges associated with sedation and laryngospasm from the results and discussions.
The variables analyzed after selecting the articles identied by the researchers that answered
the primary questions were: type of sedative used, laryngospasm during or after the surgical procedure,
characteristics of the participants who developed laryngospasm, and their evolution afterwards.
During the analysis of the included studies, it was assessed whether they had the necessary
methodological quality and information to avoid selection, measurement, and confounding biases. The
researchers compared the study groups in order to nd similarities. The inclusion and exclusion criteria
were carefully applied to make the review more homogeneous, generating applicability.
Results
The initial search with the selected words in the databases totaled a selection of 1360 results,
subsequently including the inclusion and exclusion criteria. At the end of the process, the titles and
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abstracts of all the publications displayed in the search strategy were analyzed, and 7 studies agreed
upon by both evaluators were selected. The study is detailed and described in the owchart, according
to PRISMA standards (Figure 1).
Figure 1. PRISMA ow diagram of study screening and selection.
Source: Authors.
The selected studies and their characteristics are detailed in Table 1, in order to visualize the
type of study, objectives, results, and conclusion individually.
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Title Design Objective Results Conclusion
Low-cost versus high-
delity pediatric
simulators for dicult
airway management
training: a randomized
study in continuing
medical education
Randomized
trial
Compare the quality and educational
impact of a full-scale simulation workshop
with an infant simulator or with a low-
cost simulator composed of an inert infant
manikin with software that displays
parameters on pediatric dicult airway
management.
We enrolled 128 physicians. Direct participation SQS,
observation SQS, ANTS scores, T0 SQS, T3 and T6
SQS were not dierent between groups.
Our low-cost simulator
should be suggested as a
less expensive alternative
to an HF simulator for
continuing medical education
in pediatric dicult airway
management.
The place of
ultrasonography in
conrming the position
of the laryngeal mask
airway in pediatric
patients
Observational
study
The incidence of suboptimal laryngeal
mask airway position and replacement in
children was evaluated using simultaneous
ultrasound imaging.
The average age of the patients was 6.27 ± 4.66
years. After evaluation with ultrasonography, 79.3%
of the laryngeal mask airways were found to be
optimally positioned, while the position of 15.9% had
to be corrected, and 4.9% had to be replaced. There
was a moderate positive correlation between the
ultrasonographic evaluation and leak test evaluation.
Relocation of the
laryngeal mask airway
was determined to be an
independent risk factor
aecting the development of
complications.
Safety and Ecacy
of the Combination of
Propofol and Ketamine
for Procedural Sedation/
Anesthesia in the
Pediatric Population
S y s t e m a t i c
Review and
Meta-analysis
The purpose of this systematic review was
to compare the safety and eectiveness
of propofol and ketamine to other drug
regimens.
Twenty-nine studies were included for analysis. Based
on low-to-moderate quality evidence, we concluded
that the use of propofol and ketamine may result in a
slight-to-small reduction in the risk of hypotension,
bradycardia, and apnea, and a slight increase in the
risk of tachycardia, hypertension, and other respiratory
adverse events, such as cough or laryngospasm.
The ratio of propofol to ketamine and comparator
drug regimen subgroups eects were important for
desaturation and some secondary outcomes.
The use of propofol and
ketamine had a minimal eect
on the incidence of adverse
events and other secondary
outcomes. Large-scale
studies are required to more
accurately estimate adverse
event rates and the eects
of propofol and ketamine on
patient-important outcomes.
Eect of Albuterol
Premedication vs Placebo
on the Occurrence
of Respiratory
Adverse Events in
Children Undergoing
Tonsillectomies
Randomized
Clinical Trial
To determine whether inhaled albuterol
sulfate (salbutamol) premedication
decreases the risk of perioperative
respiratory adverse events in children
undergoing anesthesia for tonsillectomy.
Of 484 randomized children (median age, 5.6 [1.6-8.9]
years; 58.9% boys, 479 data sets were available for
intention-to-treat analysis. Perioperative respiratory
adverse events occurred in 27.8% receiving albuterol
and 47.9% receiving placebo. After adjusting for age,
type of airway device, and severity of obstructive
sleep apnea in a binary logistic regression model,
the likelihood of perioperative respiratory adverse
events remained signicantly higher in the placebo
group compared with the albuterol group. Signicant
dierences were seen in children receiving placebo vs
albuterol in laryngospasm.
Albuterol premedication
administered before
tonsillectomy under general
anesthesia in young children
resulted in a clinically
signicant reduction in rates
of perioperative respiratory
adverse events compared
with the rates in children
who received placebo.
Premedication with albuterol
should be considered
for children undergoing
tonsillectomy.
List of selected articles and their characteristics.
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Incidence of post-
anesthetic respiratory
complications in
pediatrics. Observational,
single-center study in
Medellin, Colombia
Retrospective
cohort study
based on
clinical record
reviews
To describe the incidence of respiratory
complications in the post-anesthesia
care unit of an intermediate complexity
center during a six-month period, and to
explore the variables associated with major
respiratory complications.
The records of 1181 patients were analyzed. The
cumulative incidences of major complications were
bronchospasm 1.44%, laryngospasm 0.68% and
respiratory depression 0.59%. There were no cases of
cardiac arrest or acute pulmonary edema. A history
of respiratory infection less than 15 days before the
procedure, rhinitis and female sex were associated
with major respiratory complications.
A low frequency of
respiratory complications
was found during care
provided by nursing sta
trained in anesthesia recovery
and pediatric airway in the
post-anesthesia care unit.
Incidence of
laryngospasm after
extubation, with the “No
Touch” in the pediatric
population
A descriptive
study
To assess the incidence of laryngospasm
with the technique of “do not Touch”
extubation, without oropharyngeal
stimuli, in pediatric patients after general
anesthesia.
50% of the children presented cough reex, after
removing tracheal tube. Two children presented
bronchospasm and two presented
laryngospasm
The presence of laryngospasm
with “do not Touch”
extubation technique, was
lower than that reported in
the literature
(5-21%).
Comparative Study of
Haemodynamic Eects
of Intravenous Ketamine-
fentanyl and Propofol-
fentanyl for Laryngeal
Mask Airway Insertions
in Children Undergoing
Herniotomy under
General Anaesthesia
in a Nigerian Tertiary
Hospital
C o m p a r a t i v e
study
We compared the haemodynamic eects
of ketamine-fentanyl and propofol-
fentanyl combinations for LMA insertion
in pediatric patients who underwent
herniotomy in our facility
The haemodynamic states of the patients were not
statistically comparable as the heart rate, systolic,
diastolic and mean arterial blood pressure were
signicantly higher and stable in the ketamine-
fentanyl group than the propofol-fentanyl group. The
incidence of apnea was signicantly lower in the
ketamine-fentanyl group compared with propofol-
fentanyl group, but post-anaesthesia discharge scores
were similar, with no signicant dierence in both
groups.
The use of ketamine-
fentanyl combination for
LMA insertion in paediatric
patients was associated
with better haemodynamic
changes and lower incidence
of apnoea when compared
with propofol-fentanyl
combination.
Source: Authors.
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Respiratory complications can be subdivided into severe primary outcomes: laryngospasm,
bronchospasm, respiratory depression, cardiac arrest, and acute pulmonary edema; and minor or mild:
stridor, persistent cough (lasting more than ten seconds), pharyngeal plug at the end of the procedure,
airway bleeding, and residual muscle relaxation (Tolosa et al., 2021).
The overall incidence of laryngospasm was 0.87% in adults, 1.7% in pediatrics, and 2.82%
in infants. The incidence of laryngospasm among pediatric patients undergoing surgery under general
anesthesia was 57 (18.4%) in the study (Birlie and Yaregal, 2020). Of these, 34 (59.6%), 12 (21.1%), and 11
(19.3%) occurred during the emergency, maintenance, and induction phases of anesthesia, respectively.
The incidence of laryngospasm in older children was double that of adults, while the incidence of
laryngospasm in younger children was three times higher than that of adults (Olsson and Hallen, 1984).
Immediate clearing of airway secretions and adequate depth of anesthesia can help prevent
laryngospasm. Inadequate depth of anesthesia, URTI, airway anomalies, multiple attempts at airway
management, and oropharyngeal secretion were predictors of laryngospasm. Therefore, additional
vigilance is required in patients with URTI, airway anomalies, or those who require multiple attempts
at airway device insertion. Combining dierent drugs, rather than administering them alone, can reduce
the dose required and minimize potential adverse eects (Hayes et al., 2020).
The comparative drug regimens in the control groups included various combinations of
propofol, ketamine, and dexmedetomidine (Hayes et al., 2020). According to von Ungern-Sternberg
et al., standard practice in his service does not include pre-oxygenation, opting for the combination of
propofol with lidocaine to potentiate analgesia and inhalation induction with sevourane. Ketamine
and fentanyl were combined with propofol to prevent depression of the cardiovascular system during
insertion of the laryngeal mask; ketamine-fentanyl and propofol-fentanyl combinations have an analgesic
eect. However, the cardiovascular eects of the two mixtures have not been fully evaluated in children
(Okeyemi et al., 2022). In addition, strategies such as the use of β2-adrenergic agonists are employed to
prevent an increase in respiratory resistance during intubation, especially benecial for high-risk groups
such as asthmatic children or those with recent respiratory tract infections (von Ungern-Sternberg et
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al., 2019).
Albuterol, a β2-adrenergic agonist, has eects other than bronchodilation that may be
benecial during anesthesia. Of the risk factors previously identied for respiratory adverse events,
many are associated with airway inammation. Albuterol acutely, both in vivo and in vitro, inhibits the
release of inammatory mediators from mast cells and may therefore also contribute to the reduction
of perioperative respiratory adverse events through reduced release of inammatory markers and
suppression of cough receptors and other reexes (von Ungern-Sternberg et al., 2019).
The comparison between the use of propofol associated with ketamine or the use of ketamine
alone in the pediatric population for sedation revealed a signicant reduction in the risk of side eects
such as nausea, vomiting, and hemodynamic and psychomimetic adverse events (Hayes et al., 2020).
This study highlights the importance of minimizing complications during the sedation and recovery
process. The recovery of airway reexes after sedation is mediated by the activation of the sympathetic
nervous system during the post-anesthetic awakening process, an essential physiological principle that
underlies the decision to extubate only after the patient is fully awake (Tolosa et al., 2021).
Propofol is a short-acting agent that provides amnesia but no analgesia and can result in
adverse events such as hypotension if administered in large doses. In contrast, ketamine, an N-methyl-
d-aspartate (NMDA) acid receptor antagonist, induces a dissociated state with a low risk of airway
compromise or apnea when administered slowly. Although ketamine does not signicantly aect stable
or elevated hemodynamic parameters (such as blood pressure and heart rate), it can cause psychomimetic
disturbances (delirium) during the recovery phase. Both ketamine and dexmedetomidine maintain
airway patency and respiratory drive better than propofol, potentially reducing the risk of desaturation
(Hayes et al., 2020).
Lejus-Bourdeau et al. addresses a comparison between low-cost (LC) and high-delity
(HF) pediatric simulators for training in dicult airway management, given that dicult intubation
remains a signicant cause of morbidity due to the physiological characteristics of infants and young
children, contributing to the rapid onset of hypoxia during apnea. Through a randomized study with 128
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physicians (including anesthesiologists, emergency physicians, and/or intensivists), participants were
distributed into two groups group, where they participated in training sessions with dicult intubation
scenarios. The quality of the simulation, self-assessment of anesthesiologists’ non-technical skills and
educational quality, were assessed immediately after training and again after 3 and 6 months. Therefore,
the low-cost simulator proved to be a viable and cost-eective alternative to the high-delity simulator
for continuing education in the management of pediatric dicult airways, without compromising the
participants perception of quality and educational impact.
Arican et al. records laryngospasm as one of the main in relation to complications during
waking hours, it developed into laryngospasm in 6 patients (7.3%). A logistic regression analysis,
including age, gender, ASA score, and relocation or correction after ultrasound, was performed to
determine independent risk factors aecting the development of complications. laryngeal mask (LMA)
relocation (OR = 2.961; p = 0.046; 95% Cl: 2.850---30.745) was determined to be an independent risk
factor aecting the development of complications. The incidence of transient laryngospasm after LMA
device placement was similar to that reported in other studies in which precautions were taken to ensure
adequate depth of anesthesia prior to device placement. There is a signicant positive relationship
between airway management and the increased incidence of preoperative adverse events, such as
laryngospasm and even death. Although LMA is not suitable for children undergoing surgery in all
cases, it has shown clear benets compared to endotracheal intubation. The frequency of preoperative
adverse events in children using LMA for airway management is lower than when using other tools or
endotracheal tubes.
Hayes et al. evaluated 29 randomized clinical studies with patients up to the age of 18 undergoing
various procedures such as upper digestive endoscopy, cardiac catheterization, burn control, tooth
extraction, hearing response testing, lumbar puncture, spinal aspiration, magnetic resonance imaging,
interventional radiology, and fracture treatment. Among the adverse eects reported in his study was
the description of the occurrence of laryngospasm, dened by other airway events, in 1676 patients.
Fifteen studies contributed to the pooled analysis, which showed an increased risk of an event with
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propofol and ketamine (RR 1.74, 95% CI, 1.07-2.83; P = 0.02), with a trivial dierence in the absolute
risk of 2 more events per 100 patients (95% CI, 0 to 6 more). The results of this systematic review and
meta-analysis suggest that the combination of propofol and ketamine probably slightly increases the
risk of respiratory events, such as cough and laryngospasm, in children and adolescents undergoing
sedation. The propofol alone subgroup, which used higher total doses of propofol, had the lowest risk,
which may be due to propofol’s suppressive eects on airway smooth muscle reexes. With the quality
of evidence classied as low due to imprecision, it can be concluded that propofol and ketamine may
slightly increase other types of airway and/or respiratory events.
Von Ungern-Sternberg et al. totaled his study with 479 children, (mean age 5.6); he cites the
occurrence of one or more respiratory adverse events recorded in 67 children (27.8%) in the salbutamol
group and 114 children (47.9%) in the placebo group. Laryngospasm, cough, and oxygen desaturation
occurred signicantly more often in the placebo group. Children in the placebo group were 2.4 times
more likely to experience a respiratory adverse event compared to children who received salbutamol
before an adenotonsillectomy or tonsillectomy (OR, 2.4; 95% CI, 1.6-3.5; P < 0.001). Statistically
signicant dierences were present between the placebo and salbutamol groups in the prevalence of
laryngospasm (28 [11.8%] vs. 12 [5.0%]; P = 0.009). This trial demonstrated a signicant reduction in
the incidence of perioperative respiratory adverse events in young children who received premedication
with salbutamol before their procedure. For every 5 children undergoing adenotonsillectomy treated
with salbutamol, one additional case of respiratory adverse events was prevented (NTT, 4.8; 95% CI,
8.6-3.5). Children receiving placebo had a 2.8 times greater chance of respiratory adverse events after
adjusting for appropriate confounding factors, with laryngospasm being the most signicantly reduced
adverse events in children receiving salbutamol compared to placebo.
Tolosa et al. in his retrospective cohort study, collected from the post-anesthetic recovery
unit, totaling 1181 patients under the age of 16, The median age was 4 years, 69.09% were male. The
most frequently performed surgical procedures were specialized pediatric procedures (44.62%) and
orthopedics (23.88%). The most frequently used device for airway management during surgery was the
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endotracheal tube (ETT) with cu (89.62%; n = 1027), 58.64%. Bronchospasm was the most frequent
major complication (1.44%), followed by laryngospasm (0.68%). The incidence of bronchospasm was 15.8
per 1000 person-hours (95% CI [9.8-24.4]), while it was 7.4/1000 person-hours for laryngospasm (95%
CI [3.7-14.8]). None of the studied factors was associated with the presence of laryngospasm. However,
the literature suggests that this complication is associated with a supercial anesthetic plan associated
with tachycardia, and its incidence may be reduced by the use of a LMA. The study has the dierential
of extubation in the anesthetic recovery room, and with the assistance of the nursing team, despite not
being a commonly used method, the total frequency of serious respiratory complications was lower
when compared to conventional care models. It also concludes that respiratory complications are more
related to anesthesia than to the patient’s history. In this cohort of pediatric patients, the care provided
by nursing sta trained in anesthetic recovery resulted in a low frequency of respiratory complications
in post-anesthetic recovery. The study also suggests that such a strategy could be implemented in other
similar centers with the aim of optimizing operating room time and resources without compromising
patient safety, but it is still important to insist on the need to identify avoidable factors that could result
in respiratory complications.
Najar-Rodríguez et al. conducted a descriptive study on 100 children aged between 0 and 9
undergoing general anesthesia. The study reveals that the occurrence of laryngospasm is inversely related
to the age of pediatric patients, with children under the age of 3 being three times more likely to face this
complication. The diversity of surgeries included in the study, the age range of the participants, and the
lack of comparison between extubation techniques contributed to the low incidence of laryngospasm
observed. In addition to age, other relevant factors include the nature of the surgery and the anesthetic
drugs used. Oral cavity surgical procedures such as tonsillectomy and adenoidectomy have a high
incidence of laryngospasm, with a likelihood of complications between 21% and 27% higher compared
to other surgeries. Similarly, bronchoscopy and endoscopy also increase the risk of laryngospasm.
Among anesthetic agents, barbiturates are the most commonly associated with this complication. In the
study, the “No Touch” extubation technique was adopted, in which the endotracheal tube is removed
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only after the patient wakes up, followed by aspiration of oral secretions while still in the deep anesthetic
plane, the patient is placed in a lateral position, and then oxygen is administered through the 100%
mask. In this way, extubation only occurs when the lungs are inated with moderate positive pressure,
which reduces the abductor response of the laryngeal muscles and thus the occurrence of laryngospasm.
Extubation was only performed when the patients had a respiratory rate appropriate for their age and
the swallowing reex was present. After removing the tube, two children (0.02%) had laryngospasm.
The incidence of laryngospasm in the pediatric age group varies, with approximately 1.74% for children
aged 0 to 9 years. This complication is more common and more severe in the rst three months of life
and increases to 2.8% in the school age group, especially among children with obesity and asthma.
Okeyemi et al. compares the hemodynamic eects of ketamine-fentanyl and propofol-
fentanyl combinations for LMA insertion in children under anesthesia, whose complications include
laryngospasm. This randomized comparative study was carried out on 80 children aged 1 to 15 years,
physical status ASA I and II, who underwent herniotomy under general anesthesia. The incidence of apnea
after insertion was signicantly higher in patients who received propofol-fentanyl compared to patients
who received ketamine-fentanyl, 33 (84.6%) patients versus 26 (65%) patients, P = 0.045. Predictably,
the incidence of apnea in the propofol-fentanyl group should be higher than in the propofol-ketamine
group because both fentanyl and propofol have the complication of apnea when used improperly during
anesthesia. In addition, these drugs potentiate each other when combined, which can exert a synergistic
apneic eect. We conclude that the use of the ketamine-fentanyl combination for insertion in pediatric
patients was associated with better hemodynamic changes and a lower incidence of respiratory events.
Conclusion
The discussions found emphasized the importance of subdividing respiratory complications
into serious ones, with the occurrence of laryngospasm being emphasized in this study. The denition
of laryngospasm is identiable in all the articles analyzed as reex closure of the vocal cords, which
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can cause airway obstruction, a potentially serious complication in pediatric anesthesia, with a more
common incidence in children than in adults, due to children’s more sensitive anatomy and respiratory
reexes¹³. Risk factors include recent respiratory infections, asthma, exposure to tobacco and other
airway irritants such as secretion or blood, gastroesophageal reux, and supercial anesthesia and
multiple attempts at airway management. Prevention is possible through the use of prophylactic
measures such as the proper use of anesthetics, avoiding excessive airway manipulation, and careful
monitoring during induction and recovery, depending only on the early identication and approach
of signs of airway obstruction, such as stridor, absence of breath sounds and cyanosis¹⁴. Prevention
includes the immediate clearing of secretions and the appropriate use of medications such as propofol,
ketamine and albuterol. Studies show that combining medications can reduce adverse eects. Training
simulators, both low and high cost, are eective in educating people about dicult airway management.
Positive communication within anesthesia teams can improve clinical performance in critical situations.
The prognosis, if properly managed, is that most episodes are resolved without long-term complications.
References
Birlie Chekol W, Yaregal Melesse D. Incidence and Associated Factors of Laryngospasm among Pediatric
Patients Who Underwent Surgery under General Anesthesia, in University of Gondar Compressive
Specialized Hospital, Northwest Ethiopia, 2019: A Cross-Sectional Study. Anesthesiology Research and
Practice. 2020 Jan 24;2020:1-6.
Black AE. Laryngospasm in pediatric practice. Pediatric Anesthesia. 2008 Apr;18(4):279-80.
Gavel G, Walker RW. Laryngospasm in Anaesthesia. Continuing Education in Anaesthesia Critical
Care & Pain [Internet]. 2014 Apr;14(2):47-51. Available from: https://academic.oup.com/bjaed/
article/14/2/47/271333
Hayes JA, Aljuhani T, De Oliveira K, Johnston BC. Safety and Ecacy of the Combination of Propofol
and Ketamine for Procedural Sedation/Anesthesia in the Pediatric Population: A Systematic Review
239
ISSN: 2763-5724 / Vol. 04 - n 04 - ano 2024
and Meta-analysis. Anesthesia & Analgesia. 2020 Jul 7;132(4):979-92.
Lejus-Bourdeau C, Pousset F, Magne C, Bazin O, Grillot N, Pichenot V. Low-cost versus high-delity
pediatric simulators for dicult airway management training: a randomized study in continuing medical
education. Brazilian Journal of Anesthesiology (English Edition). 2021 Jun;
Liu H, Cao Y, Zhang L, Liu X, Gu E. Pressure-Controlled Volume-Guaranteed Ventilation Improves
Respiratory Dynamics in Pediatric Patients During Laparoscopic Surgery: A Prospective Randomized
Controlled Trial. International Journal of General Medicine. 2021 Jun;Volume 14:2721-8.
Najar-Rodríguez DA, González-Cordero G, Garduño-Chávez BI, Palacios-Ríos D, Najar-Rodríguez
DA, González-Cordero G, et al. Incidencia de laringoespasmo después de extubación, con técnica
“No Touch” en población pediátrica. Anestesia en México [Internet]. 2019 Aug 1 [cited 2024 Jul
19];31(2):26-33. Available from: http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S2448-
87712019000200026&lng=es.
Olsson GL, Hallen B. Laryngospasm During Anaesthesia. A Computer-Aided Incidence Study in 136
929 Patients. Acta Anaesthesiologica Scandinavica. 1984 Oct;28(5):567-75.
Okeyemi A, Suleiman AZ, Oyedepo OO, Bolaji BO, Adegboye BM, Ige OA. Comparative Study of
Haemodynamic Eects of Intravenous Ketamine-fentanyl and Propofol-fentanyl for Laryngeal Mask
Airway Insertions in Children Undergoing Herniotomy under General Anaesthesia in a Nigerian
Tertiary Hospital. Nigerian Postgraduate Medical Journal [Internet]. 2022 Jan 1 [cited 2023 Sep
1];29(1):36. Available from: https://journals.lww.com/npmj/Fulltext/2022/29010/Comparative_Study_
of_Haemodynamic_Eects_of.6.aspx
Sule Arican, Sevgi Pekcan, Gulcin Hacibeyoglu, Merve Yusifov, Sait Yuce, Sema Tuncer Uzun. The
place of ultrasonography in conrming the position of the laryngeal mask airway in pediatric patients:
an observational study. Brazilian journal of anesthesiology/Brazilian Journal of Anesthesiology. 2021
Sep 1;71(5):523-9.
Tolosa Pérez H, Gómez Santamaría S, Quintana Puerta L, Bedoya López MA, Echeverri Restrepo N,
Gallo Parra A, et al. Incidence of post-anesthetic respiratory complications in pediatrics. Observational,
single-center study in Medellin, Colombia. Colombian Journal of Anesthesiology. 2021 Apr 6;49(3).
240
ISSN: 2763-5724 / Vol. 04 - n 04 - ano 2024
von Ungern-Sternberg BS, Sommereld D, Slevin L, Drake-Brockman TFE, Zhang G, Hall GL. Eect
of Albuterol Premedication vs Placebo on the Occurrence of Respiratory Adverse Events in Children
Undergoing Tonsillectomies. JAMA Pediatrics. 2019 Jun 1;173(6):527.
Weller JM, Webster CS. Normalizing good communication in hospital teams. British Journal of
Anaesthesia [Internet]. 2021 Apr 1;126(4):758-60. Available from: https://www.bjanaesthesia.org/article/
S0007-0912(21)00003-9/fulltext
Holzki J, Laschat M. Laryngospasm. Pediatric Anesthesia. 2008 Nov;18(11):1144-6.
