Prospective, randomized comparison of laryngeal tube and laryngeal mask airway in pediatric patients

[Update 2022: interdisciplinary statement on airway management with supraglottic airway devices in pediatric emergency medicine-The laryngeal mask is and remains state of the art : Joint statement of the Institute for Emergency Medicine and Medicine Management (INM), the University Clinic Munich, LMU Munich, Germany, the Working Group for Pediatric Critical Care and Emergency Medicine of the German Interdisciplinary Society for Critical Care and Emergency Medicine (DIVI), the Medical Directors of Emergency Medical Services in Bavaria (ÄLRD), the Scientific Working Group for Pediatric Anesthesia (WAKKA) of the German Society for Anesthesiology and Intensive Care Medicine (DGAI), the Scientific Working Group for Emergency Medicine of the German Society for Anesthesiology and Intensive Care Medicine (DGAI) and the Society of Neonatology and Pediatric Critical Care Medicine (GNPI)]

BACKGROUND

Airway management with supraglottic airway devices (SGA) in life-threatening emergencies in children is increasingly being used. Different specifications of laryngeal masks (LM) and the laryngeal tube (LT) are commonly used devices for this purpose. We present a literature review and interdisciplinary consensus statement of different societies on the use of SGA in pediatric emergency medicine.

MATERIAL AND METHODS

Literature review in the PubMed database and classification of studies according to the criteria of the Oxford Centre for Evidence-based Medicine. Levels and consensus finding within the group of authors.

RESULTS

The evidence for successful applications of the various types of LM is significantly higher than for LT application. Reported smaller series of successful applications of LT are currently limited to selected research groups and centers. Especially for children below 10 kg body weight there currently exists insufficient evidence for the successful application of the LT and therefore its routine use cannot be recommended. SGAs used for emergencies should have a gastric drainage possibility.

DISCUSSION

Considering the scientific data and the large clinical experience with the LM in medical routine and emergency situations in children currently only the LM can be recommended for alternative (i.e., non-intubation) emergency airway management in children. If alternative airway management is part of a local emergency strategy, the LM should be provided in all pediatric sizes (1, 1½, 2, 2½, 3) for out of hospital use and in hospital emergency use and all users should regularly be trained in its application.

Prehospital Supraglottic Airways: An NAEMSP Position Statement and Resource Document

Supraglottic airway (SGA) devices provide effective conduits for oxygenation and ventilation and may offer protection from gastric aspiration. SGA devices are widely used by EMS clinicians as both rescue and primary airway management devices. While in common use for more than four decades, major developments in SGA education, science, and technology have influenced clinical strategies of SGA insertion and use in prehospital airway management for patients of all ages. NAEMSP recommends:SGAs have utility as a primary or secondary EMS airway intervention. EMS agencies should select SGA strategies that best suit available resources and local clinician skillset, as well as the nature of their clinical practice setting.EMS agencies that perform endotracheal intubation must also equip their clinicians with SGA devices and ensure adequate training and competence.In select situations, drug-assisted airway management may be used by properly credentialed EMS clinicians to facilitate SGA insertion.Confirmation of initial and continuous SGA placement using waveform capnography is strongly encouraged as a best practice.When it is functioning properly, EMS clinicians should refrain from converting an SGA to an endotracheal tube. The decision to convert an SGA to an endotracheal tube must consider the patient's condition, the effectiveness of SGA ventilations, and the clinical context and course of initial SGA insertionSGA training, competency, and clinical use must be continuously evaluated by EMS agencies using focused quality management programs.

A network meta-analysis of the clinical properties of various types of supraglottic airway device in children

We conducted both conventional pairwise and Bayesian network meta-analyses to compare the clinical properties of supraglottic airway devices in children. We searched six databases for randomised clinical trials. Our primary end-points were oropharyngeal leak pressure, risk of insertion failure at first attempt, and blood staining risk. The risk of device failure, defined as the abandonment of the supraglottic airway device and replacement with a tracheal tube or another device, was also analysed. Sixty-five randomised clinical trials with 5823 participants were identified, involving 16 types of supraglottic airway device. Network meta-analysis showed that the i-gel™, Cobra perilaryngeal airway™ and Proseal laryngeal mask airway (LMA^® -Proseal) showed statistically significant differences in oropharyngeal leak pressure compared with the LMA^® -Classic, with mean differences (95% credible interval, CrI) of 3.6 (1.9-5.8), 4.6 (1.7-7.6) and 3.4 (2.0-4.8) cmH₂ O, respectively. The i-gel was the only device that significantly reduced the risk of blood staining of the device compared with the LMA-Classic, with an odds ratio (95%CrI) of 0.46 (0.22-0.90). The risk (95%CI) of device failure with the LMA-Classic, LMA^® -Unique and LMA-Proseal was 0.36% (0.14-0.92%), 0.49% (0.13-1.8%) and 0.50% (0.23-1.1%), respectively, whereas the risk (95%CI) of the i-gel and PRO-Breathe was higher, at 3.4% (2.5-4.7%) and 6.0% (2.8-12.5%), respectively. The risk, expressed as odds ratio (95%CrI), of insertion failure at first attempt, was higher in patients weighing < 10 kg at 5.1 (1.6-20.1). We conclude that the LMA-Proseal may be the best supraglottic airway device for children as it has a high oropharyngeal leak pressure and a low risk of insertion. Although the i-gel has a high oropharyngeal leak pressure and low risk of blood staining of the device, the risk of device failure should be evaluated before its routine use can be recommended.

[Interdisciplinary consensus statement on alternative airway management with supraglottic airway devices in pediatric emergency medicine: Laryngeal mask is state of the art]

BACKGROUND

Airway management with supraglottic airway devices (SGA) in life-threatening emergencies involving children is becoming increasingly more important. The laryngeal mask (LM) and the laryngeal tube (LT) are devices commonly used for this purpose. This article presents a literature review and consensus statement by various societies on the use of SGA in pediatric emergency medicine.

MATERIAL AND METHODS

Literature search in the database PubMed and classification of studies according to the criteria of the Oxford Centre for Evidence-based Medicine levels of evidence.

RESULTS

The evidence for successful application of the various types of LM is significantly higher than for LT application. Reports of smaller series of successful applications of LT are currently limited to selected research groups and centers. Insufficient evidence currently exists for the successful application of the LT especially for children below 10 kg body weight and, therefore, its routine use cannot currently be recommended. SGAs used for emergencies should have a possibility for gastric drainage.

DISCUSSION

Considering the scientific data and the large clinical experience with the LM in medical routine and emergency situations in children, currently only the LM can be recommended for alternative (i.e. non-intubation) airway management in children. If alternative airway management is part of a local emergency strategy, the LM should be provided in all pediatric sizes (1, 1.5, 2, 2.5, 3, 4 and 5) for prehospital and in-hospital emergency use and all users should be regularly trained in its application.

Comparing the Laryngeal Mask Airway, Cobra Perilaryngeal Airway and Face Mask in Children Airway Management

OBJECTIVE

We compared the effects of the laryngeal mask airway (LMA), face mask and Cobra perilaryngeal airway (PLA) in the airway management of spontaneously breathing paediatric patients undergoing elective inguinal surgery.

METHODS

In this study, 90 cases of 1-14-year-old children undergoing elective inguinal surgery were scheduled. The patients were randomly divided into three groups. Anaesthesia was provided with sevoflurane and 50%-50% nitrous oxide and oxygen. After providing an adequate depth of anaesthesia, supraglottic airway devices were inserted in the group I and II patients. The duration and number of insertion, haemodynamic parameters, plateau and peak inspiratory pressure and positive end-expiratory pressure of the patients were recorded preoperatively, after induction and at 5, 10, 15 and 30 min peroperatively.

RESULTS

There were no statistical differences between the groups in terms of haemodynamic parameters (p>0.05). In group II, instrumentation success was higher and instrumentation time was shorter than group II. The positive end-expiratory pressure and plateau and peak inspiratory pressure values were statistically lower in group II (p<0.05).

CONCLUSION

We concluded that for airway safety and to avoid possible complications, LMA and Cobra PLA could be alternatives to face mask and that the Cobra PLA provided lower airway pressure and had a faster and more easy placement than LMA.

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.

Alternative airways for the pediatric emergency department

Securing the pediatric airway in the emergency setting is an uncommon event that is complicated by anatomic, physiologic, and environmental factors. Even more uncommonly, practitioners are faced with the added complication of a difficult airway, and the question of what alternatives to traditional endotracheal intubation are available and most useful may arise. Timely and effective intervention determines the patient's clinical outcome. The purpose of this review was to detail specific alternative airway management strategies and tools for use in the pediatric emergency department.

Randomized evaluation of the size 2 laryngeal tube and classical laryngeal mask airway in different head and neck positions in children under positive pressure ventilation

PURPOSE

The aim of this study was to evaluate the applicability of the laryngeal tube (LT) size 2 and the classical laryngeal mask airway (LMA) size 2 in different head-neck positions under positive pressure ventilation in children by measuring leak pressures, peak pressures and the achievable tidal volumes under positive pressure ventilation.

METHODS

Forty children were randomized to receive airway management by either the LT or LMA as the primary device. Leak pressures, peak pressures and tidal volumes under positive pressure ventilation were measured in the neutral, anteflection, retroversion, left-rotation and right-rotation head-neck positions.

RESULTS

In all head-neck positions, the leak pressures were significantly higher for the LT than for the LMA (neutral 25.9 ± 7.0 vs. 19.1 ± 5.7 cmH2O; anteflection 29.7 ± 7.1 vs. 24.2 ± 8.9 cmH2O; retroversion 24.1 ± 7.6 vs. 17.2 ± 6.9 cmH2O). In both devices, the peak ventilation pressures were higher in the anteflection position (LT 27.1 ± 6.3 cmH2O; LMA 17.8 ± 6.7 cmH2O) than in the retroversion position (LT 13.7 ± 3.9 cmH2O; LMA 12.7 ± 3.6 cmH2O). Compared to the respirator settings, lower tidal volumes were achieved in the anteflection position (LT 65 ± 48 vs. 129 ± 38 ml, LMA 100 ± 21 vs. 125 ± 29 ml) as compared to the other positions.

CONCLUSION

Based on our results, we suggest that in anaesthetized children, the size 2 LT, compared to the size 2 LMA, may be more suitable for positive pressure ventilation due to favorable leak and peak pressures. Both devices can be safely used in head-neck positions other than neutral. Most disadvantageous with regards to the measured parameters was the anteflection position, especially for the LT.

Laryngeal mask airway vs the endotracheal tube in paediatric airway management: A meta-analysis of prospective randomised controlled trials

A meta-analysis was performed on prospective randomised controlled trials to assess whether the laryngeal mask airway (LMA) offered any advantage over the conventional endotracheal tube in the paediatric age group. Using the Cochrane methodology, a literature search was carried out through peer-reviewed indexed journals in three medical databases to obtain all publications comparing the LMA with the endotracheal tube in the paediatric age group (age less than 12 years), available till December 2010. Data from 16 randomised controlled clinical trials were selected for analysis. A null hypothesis was formed against each of the seven issues tested using the Fisher's method of combining P values. The LMA was seen to have three advantages over the tracheal tube in the form of lower incidence of cough during emergence, lower incidence of postoperative sore throat and lower incidence of postoperative vomiting (P<0.05). It was seen to offer no advantage over the tracheal tube in incidence of bronchospasm or laryngospasm during emergence; also, it did not offer any advantage in increasing the efficacy of the airway seal. The only disadvantage the LMA had over the tracheal tube was its greater incidence of placement failure in the first attempt.

Paramedic King Laryngeal Tube airway insertion versus endotracheal intubation in simulated pediatric respiratory arrest

INTRODUCTION

Pediatric endotracheal intubation (ETI) is difficult and can have serious adverse events when performed by paramedics in the prehospital setting. Paramedics may use the King Laryngeal Tube airway (KLT) in difficult adult airways, but only limited data describe their application in pediatric patients.

OBJECTIVE

To compare paramedic airway insertion speed and complications between KLT and ETI in a simulated model of pediatric respiratory arrest.

METHODS

This prospective, randomized trial included paramedics and senior paramedic students with limited prior KLT experience. We provided brief training on pediatric KLT insertion. Using a random allocation protocol, participants performed both ETI and KLT on a pediatric mannequin (6-month old size) in simulated respiratory arrest. The primary outcomes were 1) elapsed time to successful airway placement (seconds), and 2) proper airway positioning. We compared airway insertion performance between KLT and ETI using the Wilcoxon signed-ranks test. Subjects also indicated their preferred airway device.

RESULTS

The 25 subjects included 19 paramedics and 6 senior paramedic students. Two subjects had prior adult KLT experience. Airway insertion time was not statistically different between the KLT (median 27 secs) and ETI (median 31 secs) (p = 0.08). Esophageal intubation occurred in 2 of 25 (8%) ETI. Airway leak occurred in 3 of 25 (12%) KLT, but ventilation remained satisfactory. Eighty-four percent of the subjects preferred the KLT over ETI.

CONCLUSIONS

Paramedics and paramedic students demonstrated similar airway insertion performance between KLT and ETI in simulated, pediatric respiratory arrest. Most subjects preferred KLT. KLT may provide a viable alternative to ETI in prehospital pediatric airway management.

Prehospital pediatric King LT-D use: a pilot study

OBJECTIVE

To determine whether prehospital providers can successfully place a pediatric King laryngeal tube (LT-D) and ventilate a Laerdal SimBaby pediatric simulator during a respiratory arrest simulation.

METHODS

We studied the ability of 45 paramedics and flight nurses to place the pediatric King LT-D in a SimBaby manikin. For the purposes of this study, paramedics and flight nurses were considered equivalent, because in this air medical system they have the same scope of practice in regard to airway skills. Because the participants had previous training and field experience with the adult King LT-D, we limited pediatric King LT-D training to our standard adult training plus selecting the correct size and inflation volumes for the device. Outcomes included rate of successful pediatric King LT-D placement, number of attempts to correctly place the tube, and time to first adequate ventilation. The subjects were evaluated on airway management using an 11-point skill test. A score of 8 or greater (≥ 73%) was considered passing. The subjects indicated their perceptions and preferences for the pediatric King LT-D using a five-point Likert scale. Data were analyzed using descriptive statistics.

RESULTS

Crew members successfully placed the pediatric King LT-D 95.5% (43/45) of the time. The median number of attempts was one. Four subjects required a second attempt; two of these subjects failed at placement. Mean time to placement was 34 seconds (95% confidence interval [CI]: 26.4-67.3 sec). Ninety percent of the participants (40/45) successfully completed the skill test, with a mean score of 78.2% (95% CI: 73.6-82.7). The subjects strongly agreed that their previous training on the adult King LT-D and using it in the field had adequately prepared them to use the pediatric King LT-D. The subjects agreed that the pediatric King LT-D was easier to place than a pediatric endotracheal tube; they strongly agreed that they would use the pediatric King LT-D as an alternative airway. The participants disagreed that they would prefer the pediatric King LT-D as a primary means of securing pediatric airways.

CONCLUSIONS

The pediatric King LT-D was quickly and reliably placed. Providers perceived the pediatric King LT-D to be easier to use than pediatric endotracheal intubation in this setting.

The I-gel, a single-use supraglottic airway device with a non-inflatable cuff and an esophageal vent: an observational study in children

BACKGROUND

The I-gel is a new single-use supraglottic airway device with a non-inflatable cuff. It is composed of a thermoplastic elastomer and a soft gel-like cuff that adapts to the hypopharyngeal anatomy. Like the LMA-ProSeal, it has an airway tube and a gastric drain tube. Little is known about its efficiency in pediatric anesthesia.

METHODS

Fifty children above 30 kg, ASA I-II, undergoing a short-duration surgery were included in this prospective, observational study. We evaluated ease in inserting the I-gel, seal pressure, gastric leak, complications during insertion and removal, ease in inserting the gastric tube and ventilatory parameters during positive pressure ventilation.

RESULTS

All devices were inserted at the first attempt. The mean seal pressure was 25 cmH(2)O. There was no gastric inflation and gastric tube insertion was achieved in all cases. The results appear similar to those in a previous study concerning laryngeal mask airway in terms of leak pressure and complication rates.

CONCLUSION

Because the I-gel has a very good insertion success rate and very few complications, it seems to be an efficient and safe device for pediatric airway management.

Flexion compromises ventilation with the laryngeal tube suction II in children

BACKGROUND

There are insufficient data as to the influence of the head and neck flexion, extension, and rotation on the ventilation with laryngeal tube suction II (LTS II). The purpose of this study was to investigate the influence of the head and neck position on oropharyngeal sealing pressure (primary outcome) and ventilation score (secondary outcome) during ventilation with the LTS II in children.

METHODS

We studied 33 children scheduled for elective surgery. Oropharyngeal sealing pressure and ventilation score were measured with the head and neck in a neutral position, flexed, extended and rotated to the right. The ventilation score was scored from 0 to 3 based on three items (no leakage with an airway pressure of 15 cmH2O, bilateral chest excursion, and a square wave capnogram; each item scored 0 or 1 point). Peak inspiratory pressure (PIP) at a tidal volume of 10 ml x kg(-1) and fiberoptic laryngeal views were also assessed in each position.

RESULTS

Although the sealing pressure was lower in the extended position [22 (8) cmH2O] than that in the neutral position [25 (7) cmH2O], there was no significant leakage during ventilation with a tidal volume of 10 ml x kg(-1). In the neutral, extended and rotated positions, the median ventilation scores were better (3 point respectively) than that with the head and neck flexed (1 point). PIP was decreased with the head and neck extended or rotated but was significantly increased in flexion position. During fibreoptic examination, the vocal cords were more easily seen in extension and right rotation, compared with the neutral position and flexion.

CONCLUSIONS

Although oropharyngeal sealing pressure is decreased with the head and neck extended, effective ventilation with LTS II can be performed like in the neutral position or the rotated position. While the sealing pressure is maintained with the head and neck flexed, flexion compromises the ventilation with LTS II in children.

[The laryngeal tube]

The laryngeal tube (VBM Medizintechnic GmbH, Sulz, Germany) is a supraglottic device designed for airway management in spontaneous or positive-pressure ventilation during anesthesia or in cardiopulmonary resuscitation. Currently, the tube is available in 4 versions: the standard laryngeal tube, the disposable tube (LT-D), the dual-lumen tube (with a tube for suction) (LTS II), and the disposable LTS (LTS-D). The design of the tube has been modified several times. It is easy to insert and the airway seal is more effective than that of the laryngeal mask. The incidence of complications is similar for both devices, though use of the laryngeal tube requires more adjustments. The standard tube is somewhat less effective than the ProSeal laryngeal mask, though the new LTS II has been improved considerably. The laryngeal tube is effective as an aid to management of the difficult airway. We reviewed the literature indexed on MEDLINE through December 2006 using the search terms laryngeal tube, anesthesia, equipment, and airway.

Alternative method for predicting optimal insertion depth of the laryngeal tube in children

BACKGROUND

Little information is available about the accuracy of the teeth mark on the laryngeal tube (LT) as a guide to correct placement in children. The aim of this crossover study was to evaluate three methods for optimal insertion depth of the size (#) 2 tube in children weighing 12-25 kg.

METHOD

In 24 children, the LT #2 was consecutively inserted by three different methods: (A) until the thick teeth mark on the tube was aligned with the upper incisors, (B) until resistance was felt, and (C) by inserting to a depth, previously measured, of the curved distance between the cricoid cartilage and the upper incisor. In each case, the depth of insertion, the degree of effective ventilation, the presence of leakage, and the fibreoptic view were assessed.

RESULTS

Insertion based on the teeth mark led to a shorter insertion depth and a greater incidence of inadequate ventilation compared with the other two methods. There was no difference in the adequacy of ventilation between methods B and C. The vocal cords were more easily identified with methods B (62.5%) and C (75%) than with method A (12.5%).

CONCLUSIONS

Insertion of the LT #2 aligned with the teeth mark can result in a shallow insertion depth and inadequate ventilation. The measured distance from the cricoid cartilage to the upper incisor offers alternative guidance for correct LT insertion.

Removal of the laryngeal tube in children: anaesthetized compared with awake

BACKGROUND

Laryngeal tube (LT) is a useful airway device in children, but there is no objective evidence that removal of LT in awake state is better than in anaesthetized state. So, we compared the incidence of respiratory adverse events after the removal of LT, either under anaesthesia or on awakening.

METHODS

Seventy healthy children between 1 and 12 yr of age were enrolled in this study. Anaesthesia was induced and maintained with sevoflurane. After induction of anaesthesia, patients were randomized into two groups: removal of LT in anaesthetized state (Group A: 2% sevoflurane) and in awake state (Group B). During and within 1 min of the removal of LT, airway complications such as upper airway obstruction, cough, vomiting, teeth clenching, hypersalivation, desaturation <90%, and laryngospasm were recorded.

RESULTS

Cough (37.1 vs 2.9%), hypersalivation (28.6 vs 5.7%), desaturation (20 vs 0%), and LT dislocation during emergence relating to the patient's movement (26.5 vs 0%) occurred more frequently in Group B (P < 0.05). Upper airway obstruction occurred more frequently (68.6 vs 31.4%) in Group A, and it was easily resolved by chin or jaw lifting.

CONCLUSION

LT removal in anaesthetized state reduced cough, hypersalivation, and prevented tube displacement and hypoxia. Upper airway obstruction in the anaesthetized state should be predicted and managed with chin or jaw lifting.