A randomized controlled trial comparing Laryngeal Mask Airway removal during adequate anesthesia and after awakening in children aged 2 to 6 years

Respiratory Adverse Events After LMA® Mask Removal in Children: A Randomized Trial Comparing Propofol to Sevoflurane

BACKGROUND

The removal of the laryngeal mask airway (LMA®) in children may be associated with respiratory adverse events. The rate of occurrence of these adverse events may be influenced by the type of anesthesia. Studies comparing total intravenous anesthesia (TIVA) with propofol and sevoflurane are limited with conflicting data whether propofol is associated with a lower incidence of respiratory events upon removal of LMA as compared to induction and maintenance with sevoflurane. We hypothesized that TIVA with propofol is superior to sevoflurane in providing optimal conditions and improved patient's safety during emergence.

METHODS

In this prospective, randomized, double-blind clinical trial, children aged 6 months to 7 years old were enrolled in 1 of 2 groups: the TIVA group and the sevoflurane group. In both groups, patients were mechanically ventilated. At the end of the procedure, LMAs were removed when patients were physiologically and neurologically recovered to a degree to permit a safe, natural airway. The primary aim of this study was to compare the occurrence of at least 1 respiratory adverse event, the prevalence of individual respiratory adverse events, and the airway hyperreactivity score following emergence from anesthesia between the 2 groups. Secondary outcomes included ease of LMA insertion, quality of anesthesia during the maintenance phase, hemodynamic stability, time to LMA removal, and incidence of emergence agitation.

RESULTS

Children receiving TIVA with propofol had a significantly lower incidence (10.8.% vs 36.2%; relative risk, 0.29; 95% CI [0.14-0.64]; P = .001) and lower severity ( P = .01) of respiratory adverse outcomes compared to the patients receiving inhalational anesthesia with sevoflurane. There were no statistically significant differences in secondary outcomes between the 2 groups, except for emergence agitation that occurred more frequently in patients receiving sevoflurane ( P < .001).

CONCLUSIONS

Propofol induction and maintenance exerted a protective effect on healthy children with minimal risk factors for developing perioperative respiratory complications, as compared to sevoflurane.

Adverse Respiratory Events After Removal of Laryngeal Mask Airway in Deep Anesthesia Versus Awake State in Children: A Randomized Trial

Background The advent of the laryngeal mask airway (LMA) has reduced respiratory events in comparison to the conventional endotracheal tubes. Any manipulation under a light plane of anesthesia predisposes to increased airway sensitivity followed by adverse events. The reduced airway sensitivity in the deeply anesthetized state makes LMA removal feasible. In the past, the respective advantages and disadvantages of extubation in two planes of anesthesia have led to conflicting results. The primary objective of this study is to compare the incidence of adverse respiratory events at the time of LMA removal, in deeply anesthetized and awake groups. Our secondary objective was to record the management of complications. Materials and methods We conducted a prospective randomized control trial in 106 American Society of Anesthesiologists (ASA) I and II patients undergoing lower umbilical surgeries over a period of one year. The demographic details and intraoperative and postoperative variables, i.e., airway obstruction, laryngospasm, peripheral oxygen desaturations, cough, straining and vomiting, along with corrective measures were recorded by the primary research assistant in both groups. Regarding the management of peripheral oxygen desaturation (less than 90%), airway obstruction, and laryngospasm, 100% fractional inspired oxygen support and chin lift/jaw thrust were used. Results The average age was 32.58±15.81 months. The demographic characteristics of the patients were not significant between the two groups. The rate of adverse respiratory events like laryngospasm and airway obstruction was relatively high in the deep group but not statistically significant between the groups. A total of 7 (6.6%) patients had laryngospasm, 21 (20%) had airway obstruction, 16 (15%) had a cough and 11 (10%) patients had observed peripheral oxygen desaturation (less than 90%) between both groups.  Conclusion We concluded that adverse respiratory events could happen in both awake and deep planes of anesthesia after the removal of LMA in children. Furthermore, both techniques have an acceptably low frequency of complications, and it does not affect the current clinical practice.

Risk assessment and optimization strategies to reduce perioperative respiratory adverse events in Pediatric Anesthesia-Part 2: Anesthesia-related risk and treatment options

Perioperative respiratory adverse events are the most common cause of critical events in children undergoing anesthesia and surgery. While many risk factors remain unmodifiable, there are numerous anesthetic management decisions which can impact the incidence and impact of these events, especially in at-risk children. Ongoing research continues to improve our understanding of both the influence of risk factors and the effect of specific interventions. This review discusses anesthesia risk factors and outlines strategies to reduce the rate and impact of perioperative respiratory adverse events with a chronologic based inquiry into anesthetic management decisions through the perioperative period from premedication to postoperative disposition.

Effectiveness and Safety of Extubation before Reversal of Neuromuscular Blockade versus Traditional Technique in Providing Smooth Extubation

Background:

Traditional extubation often leads to bucking, coughing, and undesirable hemodynamic changes. Extubation just before administering reversal could reduce force of coughing, bucking and may provide better extubation conditions.

Aim of Study:

The aim of the study was to assess the incidence of bucking with extubation just before administering reversal of neuromuscular blockade compared to traditional technique of awake extubation. Incidence of coughing during extubation, vomiting/regurgitation, aspiration, hemodynamic changes, postoperative bleeding, and extubation conditions were also assessed.

Settings and Design:

This was a prospective randomized study conducted in a tertiary care institute.

Subjects and Methods:

Forty patients were allocated into two equal groups. In Group E, at the end of surgery, extubation was performed and reversal was administered after extubation. In Group L, reversal was given and patients were extubated in the traditional way. Quality of extubation was assessed using extubation quality score.

Statistical Tests Used:

Pearson Chi-square test, Fisher's exact test, and independent sample t-test.

Results:

Group E showed significantly lower incidence of bucking (15% vs. 65%) and coughing (10% vs. 45%). Incidences of desaturation and regurgitation/aspiration were comparable. In Group E, 85% of patients did not cough during extubation compared to 50% in Group L. Extubation quality was significantly better in Group E. Although extubation time was significantly shorter in Group E, recovery time was comparable in both groups.

Conclusion:

Extubation just before reversal of neuromuscular blockade resulted in lesser incidence of bucking and coughing during extubation with lesser postoperative bleeding compared to traditional technique of awake extubation without added risks of regurgitation, aspiration, or delayed recovery.

The place of ultrasonography in confirming the position of the laryngeal mask airway in pediatric patients: an observational study

Background and objectives

Laryngeal mask airways are increasingly used as supraglottic devices during general anesthesia. Ultrasonography can provide a dynamic image simultaneous to placing the supraglottic airway device. In the current study, the incidence of suboptimal laryngeal mask airway position and replacement in children was evaluated using simultaneous ultrasonographic imaging.

Methods

A prospective observational study was conducted on 82 patients aged 3–15 years with American Society of Anesthesiologists (ASA) physical status I or II. Patients under general anesthesia and with airway provided by a laryngeal mask airway were included. The position of the laryngeal mask airway was evaluated by ultrasonography on two planes. According to our scoring system, Grade I and Grade II were determined to indicate acceptable placement, while Grade III was determined to indicate unacceptable placement. Suboptimal laryngeal mask airway placement rates and the requirement of replacement were determined. Laryngeal mask airway placement optimized by ultrasonography was evaluated with both leak tests and a fiberoptic laryngoscope.

Results

The average age of the patients was 6.27 ± 4.66 years. After evaluation with ultrasonography, 65 (79.3%) of the laryngeal mask airways were found to be optimally positioned, while the position of 13 (15.9%) had to be corrected, and 4 (4.9%) had to be replaced. There was a moderate positive correlation between the ultrasonographic evaluation and leak test evaluation (p < 0.001; r = 0.628). Relocation of the laryngeal mask airway was determined to be an independent risk factor affecting the development of complications (OR = 2.961; p = 0.046; 95% Cl 2.850–30.745).

Conclusion

The use of ultrasonography to verify and relocate laryngeal mask airway placement is noninvasive and effective.

The impact of topical lidocaine and timing of LMA removal on the incidence of airway events during the recovery period in children: a randomized controlled trial

Background

The timing of laryngeal mask airway (LMA) removal remains undefined. This study aimed to assess the optimal timing for LMA removal and whether topical anesthesia with lidocaine could reduce airway adverse events.

Methods

This randomized controlled trial assessed one-to-six-year-old children with ASA I-II scheduled for squint correction surgery under general anesthesia. The children were randomized into the LA (lidocaine cream smeared to the cuff of the LMA before insertion, with mask removal in the awake state), LD (lidocaine application and LMA removal under deep anesthesia), NLA (hydrosoluble lubricant application and LMA removal in the awake state) and NLD (hydrosoluble lubricant application and LMA removal in deep anesthesia) groups. The primary endpoint was a composite of irritating cough, laryngeal spasm, SpO₂ < 96%, and glossocoma in the recovery period in the PACU. The secondary endpoints included the incidence of pharyngalgia and hoarseness within 24 h after the operation, duration of PACU stay, and incidence of agitation in the recovery period. The assessor was unblinded.

Results

Each group included 98 children. The overall incidence of adverse airway events was significantly lower in the LA group (9.4%) compared with the LD (23.7%), NLA (32.6%), and NLD (28.7%) groups (P=0.001). Cough and laryngeal spasm rates were significantly higher in the NLA group (20.0 and 9.5%, respectively) than the LA (5.2 and 0%, respectively), LD (4.1 and 1.0%, respectively), and NLD (9.6 and 2.1%, respectively) groups (P=0.001). Glossocoma incidence was significantly lower in the LA and NLA groups (0%) than in the LD (19.6%) and NLD (20.2%) groups (P< 0.001). At 24 h post-operation, pharyngalgia incidence was significantly higher in the NLA group (15.8%) than the LA (3.1%), LD (1.0%), and NLD (3.2%) groups (P< 0.001).

Conclusions

LMA removal in the awake state after topical lidocaine anesthesia reduces the incidence of postoperative airway events.

Trial registration

ChiCTR, ChiCTR-IPR-17012347. Registered August 12, 2017.

Deep vs. Awake Extubation and LMA Removal in Terms of Airway Complications in Pediatric Patients Undergoing Anesthesia: A Systemic Review and Meta-Analysis

The purpose of this study was to compare the incidence of airway complications between extubation under deep anesthesia (deep extubation) and extubation when fully awake (awake extubation) in pediatric patients after general anesthesia. A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) statement standards. The review protocol was registered with the International Prospective Register of Systematic Reviews (registration number: CRD 42018090172). Electronic databases were searched, without discrimination of publication year and language, to identify all randomized controlled trials investigating airway complications following deep or awake extubation after general anesthesia. The Cochrane tool was used to assess the risk of bias of trials. Randomized trials investigating airway complications of deep extubation compared with awake extubation after general anesthesia with an endotracheal tube and laryngeal mask airway (LMA) were sought. Overall airway complications, airway obstruction, cough, desaturation, laryngospasm and breath holding were analyzed using random-effect modelling. The odds ratio was used for these incidence variables. Seventeen randomized trials were identified, and a total of 1881 pediatric patients were enrolled. The analyses indicated deep extubation reduces the risk of overall airway complications (odds ratio (OR) 0.56, 95% confidence interval (CI) 0.33–0.96, p = 0.04), cough (OR 0.30, 95% CI 0.12–0.72, p = 0.007) and desaturation (OR 0.49, 95% CI 0.25–0.95, p = 0.04) in children after general anesthesia. However, deep extubation increased the risk of airway obstruction compared with awake extubation (OR 3.38 CI 1.69–6.73, p = 0.0005). No difference was observed in the incidence of laryngospasm and breath-holding between the two groups regardless of airway device. The result of this analysis indicates that deep extubation may decrease the risk of overall airway complications including cough and desaturation but may increase airway obstruction compared with awake extubation in pediatric patients after general anesthesia. Therefore, deep extubation may be recommended in pediatric patients to minimize overall airway complications except airway obstruction and the clinicians may choose the method of extubation according to the risk of airway complications of pediatric patients.

Deep or awake removal of laryngeal mask airway in children at risk of respiratory adverse events undergoing tonsillectomy-a randomised controlled trial

BACKGROUND

Laryngeal mask airways (LMA) are widely used during tonsillectomies. Contrasting evidence exists regarding the timing of the removal and the risk of perioperative respiratory adverse events. We assessed whether the likelihood of perioperative respiratory adverse events is influenced by the timing of LMA removal in children with at least one risk factor for these events.

METHODS

Participants (n=290, 0-16 yr) were randomised to have their LMA removed either deep (in theatre by anaesthetist at end-tidal sevoflurane >1 minimum alveolar concentration) or awake (in theatre by anaesthetist or in postanaesthesia care unit by anaesthetist or trained nurse). The primary outcome was the occurrence of perioperative respiratory adverse events over the whole emergence and postanaesthesia care unit phases of anaesthesia. The secondary outcome was the occurrence of perioperative respiratory adverse events over the distinct phases of emergence and postanaesthesia care unit.

RESULTS

Data from 283 participants were analysed.

PRIMARY OUTCOME

even though a higher occurrence of adverse events was observed in the awake group, no evidence for a difference was found [45% vs 35%, odds ratio (OR): 1.5, 95% confidence interval (CI): 0.9-2.5, P=0.09]. Secondary outcome: there was no evidence for a difference between the groups during emergence [19 (14%) deep vs 25 (18%) awake, OR: 0.74, 95%CI: 0.39-1.42, P=0.37]. However, in the postanaesthesia care unit, children with an awake rather than deep removal experienced significantly more adverse events [55 (39%) vs 37 (26%); OR: 1.85, 95%CI: 1.12-3.07, P=0.02].

CONCLUSION

We found no evidence for a difference in the timing of the LMA removal on the incidence of respiratory adverse events over the whole emergence and postanaesthesia care unit phases. However, in the postanaesthesia care unit solely, awake removal was associated with significantly more respiratory adverse events than deep removal.

TRIAL REGISTRATION NUMBER

ACTRN12609000387224 (www.anzctr.org.au).

Early versus late removal of the laryngeal mask airway (LMA) for general anaesthesia

BACKGROUND

The laryngeal mask airway (LMA) is a safe and effective modality to maintain the airway for general anaesthesia during surgical procedures. The LMA is removed at the end of surgery and anaesthesia, when the patient maintains an adequate respiratory rate and depth. This removal of the LMA can be done either when the patient is deep under anaesthesia (early removal) or only after the patient has regained consciousness (late removal). It is not clear which of these techniques is superior.

OBJECTIVES

The objective of this review was to compare the safety of LMA removal in the deep plane of anaesthesia (early removal) versus removal in the awake state (late removal) for participants undergoing general anaesthesia.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 8); MEDLINE (1966 to August 2014); EMBASE (1980 to August 2014); LILACS (1982 to August 2014); CINAHL (WebSPIRS; 1984 to August 2014); and ISI Web of Science (1984 to August 2014). We searched for ongoing trials through various trial registration websites. In addition, we searched conference proceedings and reference lists of relevant articles.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) on adults and children undergoing elective general anaesthesia using the LMA, that compared early removal of the LMA (defined as removal of the LMA in the deep plane of anaesthesia) versus late removal of the LMA (defined as removal of the LMA after the patient is awake).

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information. We used a random-effects model to generate forest plots from the data.

MAIN RESULTS

We identified a total of 9188 citations and included 15 RCTs conducted on 2242 participants in this review. All trials used the LMA Classic in American Society of Anesthesiologists (ASA) physical status I or II for patients undergoing elective general anaesthesia. Children were enrolled in 11 trials and adults in five trials. None of the trials were of high methodological quality. Eight of the 15 studies had adequate generation of random sequence, whereas only one trial had adequate concealment of random sequence. Three trials had blinded the outcome assessor. Thus, the majority of the studies appeared to have a high risk of bias in the study design.Using the GRADE approach, we found low quality evidence that the risk of laryngospasm was similar with early removal of the LMA (3.3%) versus late removal (2.7%): risk ratio (RR) 1.23, 95% confidence interval (CI) 0.74 to 2.03; 11 trials, 1615 participants. The quality of evidence was very low that the risk of coughing was less after early removal (13.9%) than late removal (19.4%): RR 0.52, 95% CI 0.29 to 0.94; 11 trials, 1430 participants. The quality of evidence for the risk of desaturation was also very low; there was no difference between early removal (7.9%) and late removal (10.1%): RR 0.68, 95% CI 0.4 to 1.16; 13 trials, 2037 participants. We found low quality evidence that the risk of airway obstruction was higher with early removal (15.6%) compared to late removal of the LMA (4.6%): RR 2.69, 95% CI 1.32 to 5.5; eight trials, 1313 participants.

AUTHORS' CONCLUSIONS

This systematic review suggests that current best evidence comparing early versus late removal of the LMA in participants undergoing general anaesthesia does not demonstrate superiority of either intervention. However, the quality of evidence available is either low or very low. There is a paucity of well designed RCTs and a need for large scale RCTs to demonstrate whether early removal or late removal of the LMA is better after general anaesthesia.

An ultrasound evaluation of laryngeal mask airway position in pediatric patients: an observational study

BACKGROUND

In children, the laryngeal mask airway (LMA) is frequently displaced within the hypopharynx, resulting in repositioning of the device. When the tip of the LMA is placed in the esophageal inlet, the arytenoids are moved ventrally. When the LMA is rotated or deviated, the ventral movement of the arytenoids may result in asymmetric elevation of an arytenoid cartilage, which can be detected with ultrasound (US). In this study, we sought to estimate the incidence of LMA malposition detected with US in pediatric patients. The primary end point was to compare the incidence of LMA malposition between US and fiber optic bronchoscopy (FOB). The secondary end points were to find the interrelationship between US-detected and FOB-detected malposition of the LMA and to locate the diagnostic performance of US in detecting LMA malposition.

METHODS

In this observational study, 100 consecutive children were included. After anesthetic induction, US evaluation was performed before and after LMA insertion to obtain the glottic image on the anterior neck. FOB was performed to assess LMA position (FOB LMA grade and LMA rotation grade). With a post-LMA US image, the symmetry of the arytenoid cartilages was evaluated. Asymmetrical elevation of an arytenoid cartilage in reference to the glottic midline and the opposite arytenoid cartilage was graded as 0 to 3 (US arytenoid grade). The interrelationships between US arytenoid grade and FOB LMA grade or LMA rotation grade were assessed.

RESULTS

The incidence of asymmetrical elevation of an arytenoid was 50% (95% confidence interval [CI], 40%-60%). On FOB, the incidence of LMA malposition was 78% (95% CI, 69%-86%), and that of LMA rotation was 43% (95% CI, 33%-53%). The incidence of LMA malposition was higher with FOB (P < 0.0001), but the incidence of rotation was similar (P = 0.395). US arytenoid grade did not correlate with FOB LMA grade (P = 0.611) but showed a significant correlation with LMA rotation grade (P < 0.0001; 95% CI, 60%-83%). To detect a rotated LMA, US had a sensitivity of 93% (95% CI, 81%-98%) and a specificity of 82% (95% CI, 70%-91%). The positive and negative predictive values were 80% (95% CI, 66%-90%) and 94% (95% CI, 83%-99%), respectively. The accuracy was 87% (95% CI, 79%-93%).

CONCLUSIONS

Although US could not detect the suboptimal depth of an LMA, US has promise of being an accurate tool in detecting a rotated LMA.

Supraglottic airway devices vs tracheal intubation in children: a quantitative meta-analysis of respiratory complications

BACKGROUND

Rate of perioperative respiratory complications between tracheal intubation (TI) and laryngeal mask airway remains unclear during pediatric anesthesia.

OBJECTIVES

The aim of the present meta-analysis was to compare the perioperative respiratory complications between laryngeal mask airway and TI.

METHODS

A meta-analysis of available controlled studies comparing laryngeal mask airway to TI was conducted. Studies including patients with airway infection were excluded. Data from each trial were combined to calculate the pooled odds ratios (OR) or mean difference (MD) and 95% confidence intervals.

RESULTS

The meta-analysis was performed on 19 studies. In 12 studies, patients were given muscle relaxation, and in 16 studies, ventilation was controlled. During recovery from anesthesia, the incidence of desaturation (OR = 0.34 [0.19-0.62]), laryngospasm (OR = 0.34 [0.2-0.6]), cough (OR = 0.18 [0.11-0.27]), and breath holding (0.19 [0.05-0.68]) was lower when laryngeal mask airway was used to secure the airway. Postoperative incidences of sore throat (OR = 0.87 [0.53-1.44]), bronchospasm (OR = 0.56 [0.25-1.25]), aspiration (1.33 [0.46-3.91]) and blood staining on the device (OR = 0.62 [0.21-1.82]) did not differ between laryngeal mask airway and TI. Results were homogenous across the studies, with the exceptions of blood staining on the device.

CONCLUSIONS

This meta-analysis found that the use of laryngeal mask airway in pediatric anesthesia results in a decrease in a number of common postanesthetic complications. It is therefore a valuable device for the management of the pediatric airway.

Endotracheal intubation versus laryngeal mask airway for esophagogastroduodenoscopy in children

OBJECTIVES

The present study examined the safety and efficacy of a laryngeal mask airway (LMA), compared with an endotracheal tube (ETT), for children undergoing elective esophagogastroduodenoscopy (EGD).

METHODS

A total of 84 American Society of Anesthesiologists (ASA) patients, status I to III, were randomly assigned to receive an ETT or LMA. All participants were premedicated with midazolam 0.5 mg/kg (up to 15 mg). Airway device placement occurred after induction with 8% sevoflurane and 100% oxygen, placement of an intravenous catheter, and intravenous lidocaine 2 mg/kg up to 100 mg. The following data were collected: time from induction of anesthesia to placement of the airway device, time from end of procedure to arrival in the postoperative acute care unit (PACU), time in the PACU, time from arrival in the operating room (OR) to discharge, vomiting after the procedure, nausea requiring medicine, lowest oxygen saturation, highest concentration of sevoflurane, highest pain, amount of pain medicine, adverse events, and satisfaction of doctor performing the EGD.

RESULTS

Group ETT had higher time from room arrival to airway placement, mask to airway placement, room arrival time to discharge, mask placement to discharge, airway placement to discharge, and end of procedure to discharge. Group ETT had a higher proportion of patients with vomiting than group LMA. No statistical difference was noted in endoscopist satisfaction when comparing ETT and LMA. The ETT group had 3 adverse events, including laryngospasm (n=2) and asthma attack (n=1).

CONCLUSIONS

The LMA appears to be an acceptable and safe alternative for otherwise healthy children undergoing routine EGD. Benefits appear to be decreased incidence of vomiting and overall decreased time spent in the hospital.