The air-Q(®) intubating laryngeal airway vs the LMA-ProSeal(TM) : a prospective, randomised trial of airway seal pressure

Comparative evaluation of self-pressurized Air-Q® and Proseal™ LMA® in patients undergoing elective surgery under general anaesthesia: A randomized clinical trial

Background and Aims

Intra-cuff pressure of Air-Q self-pressurized laryngeal airways (Air-Q SP) balances airway pressure and adapts to patient's pharyngeal and periglottic structures, thus improves oropharyngeal leak pressure (OLP).This study was performed to compare efficacy of Air-Q SP with Proseal laryngeal mask airway (PLMA) in patients undergoing elective surgery.

Material and Methods

The study design was prospective, randomized and controlled. Ninety patients were randomly assigned to Air-Q SP or PLMA group. All patients were premedicated and shifted to operation theatre. Monitoring was instituted. After securing IV-line, induction with inj. Morphine + Propofol, relaxation with inj. Vecuronium was done. Supraglottic was inserted according to group allocation. Outcome measures were OLP, fibreoptic view of larynx, success rate, device insertion parameters, haemodynamic and respiratory parameters and post-operative laryngopharyngeal complications. Neostigmine + glycopyrrolate were given, device was extubated.

Results

All supraglottic airway devices (SADs) were successfully placed in two attempts. The mean initial OLP, OLP at 10 minutes, and device insertion time were significantly lower in Air-Q SP group. Fiber-optic laryngeal view grading was significantly better with Air-Q SP. No significant difference was observed with respect to rate of successful insertion in first attempt, ease of insertion, and manipulations required. The hemodynamic/respiratory parameters and post-operative sore throat in the two both groups were similar.

Conclusions

Proseal LMA has a higher OLP than Air-Q SP but average insertion time was better, and fiber-optic grading of laryngeal view was shorter with Air-Q SP. However, Air-Q SP and Proseal LMA were both effective for lung ventilation.

Supraglottic airway devices: a powerful strategy in airway management

The escalating airway management demands of cancer patients have prompted us to continually curate airway devices, with supraglottic airway devices (SADs) playing a significant role in this regard. SADs serve as instrumental tools for maintaining an open upper airway. Since the inception of the earliest SADs in the early 1980s, an array of advanced and enhanced second-generation devices have been employed in clinical settings. These upgraded SADs integrate specific features designed to enhance positive-pressure ventilation and mitigate the risk of aspiration. Nowadays, they are extensively used in general anesthesia procedures and play a critical role in difficult airway management, pre-hospital care, and emergency medicine. In certain situations, SADs may be deemed a superior alternative to endotracheal tube (ETT) and can be employed in a broader spectrum of surgical and non-surgical cases. This review provides an overview of the current evidence, a summary of classifications, relevant application scenarios, and areas for improvement in the development or clinical application of future SADs.

Comparative evaluation of Air-Q blocker and Proseal laryngeal mask airway in patients undergoing elective surgery under general anaesthesia: A randomised controlled trial

Background and Aims:

The Air-Q blocker (Cook gas LLC, Mercury Medical, Clearwater, FL, USA) is a relatively new supraglottic airway device (SAD) with capability to serve as a conduit for intubation. As there is limited data on Air-Q blocker, the present study was performed to compare the efficacy of Air-Q blocker and Proseal laryngeal mask airway (PLMA) in patients undergoing elective surgery.

Methods:

A total of 90 American Society of Anesthesiologists (ASA) physical status I and II patients were randomly allocated to Air-Q blocker or PLMA group. Oropharyngeal leak pressure (OLP), insertion success, insertion time, ease of orogastric tube (OGT) insertion, fibreoptic visualisation of the glottis, haemodynamic and ventilation parameters, and complications at emergence and postoperatively were investigated.

Results:

OLPs were higher in PLMA group as compared to Air-Q blocker group (P = 0.002). Still, the OLP (27.5 ± 5.8 cm H₂O) was clinically effective in Air-Q blocker group. The mean time for successful insertion was significantly shorter for Air-Q blocker than PLMA (P = 0.019). The number of attempts to insert both the devices was comparable (P ≥ 0.05). Air-Q blocker provided a significantly better fibreoptic score than PLMA (P = 0.038). The two groups were comparable in terms of ease of OGT insertion, haemodynamics and ventilation parameters, and complications at emergence and postoperatively.

Conclusions:

Air-Q blocker provides a clinically effective OLP though PLMA provides a slightly better sealing function in patients undergoing laparoscopic and non-laparoscopic surgeries under general anaesthesia requiring neuromuscular blockade. Air-Q blocker has shorter insertion time and a better fibreoptic view of glottis as compared to PLMA.

Low skill fibreoptic intubation using i-gel™ and air-Q™ in simulated difficult airways: A randomised study in manikin and in patients

Background:

Fibreoptic intubation via a supraglottic device (SAD) is ‘low skill fibreoptic intubation’ (LSFOI). ‘Standard’ second generation SADs (i-gelTM) have a gastric port. ‘Specialised’ second generation SADs (air-QTM) are designed to facilitate LSFOI and have wider ventilation ports. Our hypothesis was that performance of LSFOI differs between i-gelTM and air-QTM in a manikin with a simulated difficult airway.

Methods:

Our primary outcome was fibreoptic intubation success rate. Our secondary outcomes included SAD insertion and LSFOI times. A difficult airway was simulated by applying a hard cervical collar to a manikin. Anaesthetists performed LSFOI serially using both SADs in a random sequence. In the manikin study, 80 anaesthetists were recruited. To test the robustness of the conclusion from our manikin study, we repeated the study in 22 anaesthetised patients. Patients were fitted with the same cervical collar and randomly allocated to either devices. We used McNemar’s statistical test to analyse our primary outcome of successful intubations and paired nominal data. A Wilcoxon signed-ranks test was used to analyse nonparametric paired data and a Mann–Whitney U test was used for unpaired data analysis where appropriate. A p-value of <0.05 was considered statistically significant.

Results:

In the manikin study, the i-gelTM was superior to the air-QTM for successful tracheal intubation (98.8% vs 83.8%, respectively; p=0.002) and LSFOI times (34.0 s vs 36.0 s, respectively; p=0.012). In the patient study, LSFOI success rates were not significantly different between i-gelTM and air-QTM (100% vs 91.6%, respectively; p=0.545) but intubation times were shorter (52.5 s vs 60.0 s, respectively; p=0.036).

Conclusion:

In conclusion, we obtained LSFOI success rates for the i-gelTM or air-QTM of 98.8% and 83.8% respectively in a manikin; and 100% and 91.6% respectively in patients. It is in fact ‘low skill’ as many participants were successful despite no prior experience with LSFOI. The i-gelTM is superior for LSFOI compared with the air-QTM. This is despite being a ‘standard’ second generation SAD as compared to a ‘specialised’ second generation SAD (air-QTM).

Trial Registration:

The manikin and patient studies were conducted after being approved by the SingHealth Centralised Institutional Review Board (CRB reference number 2014/2039 and 2016/2069, respectively). The patient study was registered at ClinicalTrials.gov (ID: NCT02663843).

Awake supraglottic airway guided flexible bronchoscopic intubation in patients with anticipated difficult airways: a case series and narrative review

Awake intubation is indicated in difficult airways if attempts at securing the airway after induction of general anesthesia may lead to harm due to potential difficulties or failure in those attempts. Conventional awake flexible bronchoscopic intubation is performed via the nasal, or less commonly, oral route. Awake oral flexible bronchoscopic intubation (FBI) via a supraglottic airway device (SAD) is a less common technique; we refer to this as ‘supraglottic airway guided’ FBI (SAGFBI). We describe ten cases with anticipated difficult airways in which awake SAGFBI was performed. After sedation and adequate airway topicalization, an Ambu Auragain^TM SAD was inserted. A flexible bronchoscope, preloaded with a tracheal tube, was then inserted through the SAD. Finally, the tracheal tube was railroaded over the bronchoscope, through the SAD and into the trachea. The bronchoscope and the SAD were carefully removed, whilst keeping the tracheal tube in-situ. The technique was successful and well tolerated by all patients, and associated complications were rare. It also offered the advantages of performing an ‘awake test insertion’ of the SAD, an ‘awake look’ at the periglottic region, and an ‘awake test ventilation.’ In certain patients, awake SAGFBI offers advantages over conventional awake FBI or awake videolaryngoscopy. More research is required to evaluate its success and failure rates, and identify associated complications. Its place in difficult airway algorithms may then be further established.

Comparison of laryngeal mask airway supremeTM as non-inflatable cuff device and self-pressurized air-QTM in children: Randomized controlled non-inferiority study

BACKGROUND

Supraglottic airway (SGA) device with non-inflatable cuff reduce the airway complications associated with cuff hyperinflation. The aim of the study is to determine whether the default setting of Supreme is as effective as the non-inflatable cuff devices. The oropharyngeal leak pressure was measured and compared between the Supreme and Air-Q, a typical non-inflatable cuff device. We hypothesized that the default setting of Supreme is non-inferior to the the Air-Q self-pressurized (SP) in respect to the oropharyngeal leak pressure.

METHODS

Eighty-four patients aged 1 to 7 years who were scheduled for general anesthesia, participated in the study. The patients were randomly assigned to Supreme group (n = 41) or Air-Q SP group (n = 43). We considered that the primary outcome, oropharyngeal leak pressure of Supreme group would be non-inferior to the Air-Q SP group, within 3 cmH2O. Other outcomes included tidal volume loss, difficulty of insertion, insertion time, and complications.

RESULTS

The oropharyngeal leak pressure of the Supreme and Air-Q SP was 19.9 ± 4.1 cm H2O and 17.4 ± 2.9 cm H2O, respectively. The mean differences of 2 devices (Air-Q SP-Supreme) were -2.5 cm H2O, (95% confidence interval [-4.0 to -0.9], P = .002). The upper CI was smaller than the non-inferiorty margin (3 cm H2O). This result suggested that the default setting of Supreme was superior to the Air-Q SP with respect to the oropharyngeal leak pressure. However, there were no significant differences in tidal volume loss over time, ease of device insertion score, insertion time, and complications.

CONCLUSIONS

The Supreme can be used in the default setting in pediatric patients accordingly in terms of tolerable leak pressure and the stability for mechanical ventilation compared with Air-Q SP.

A simple and safe method for tracheal intubation using a supraglottic intubation-aid device in mice

Although mice are a commonly used animal species in experimental medicine, airway management of this species is not easy due to their small size. In order to develop a new method of tracheal intubation in mice, we produced a supraglottic intubation-aid conduit (SIAC) for mice, and tested the efficacy of this device in spontaneously breathing mice anesthetized with sevoflurane inhalation. The success rate of tracheal intubation with the crude prototype of the SIAC was 50% and adverse effects on respiration and some trauma in the upper airway were occasionally observed. After refining the size and shape of the SIAC, the success rate of tracheal intubation with the refined prototype of the SIAC was 100% without any serious adverse effects. This study showed that it is possible to produce a supraglottic airway device to aid tracheal intubation in mice and that the shape and size of the SIAC play a crucial role in successful tracheal intubation in mice.

A comparison between ProSeal laryngeal mask airway and Air-Q Blocker in patients undergoing elective laparoscopic cholecystectomy

Background and Aims:

ProSeal laryngeal mask airway (PLMA) is an established device for airway management, while Air-Q Blocker (AQB) is a relatively new supraglottic device. The aim of this study is to compare AQB against PLMA in adults undergoing laparoscopic cholecystectomy under general anesthesia.

Material and Methods:

Eighty-eight adult patients scheduled for laparoscopic cholecystectomy under general anesthesia were randomly allocated into two groups. A drain tube (gastric tube for PLMA and blocker tube for AQB) was inserted through the drain channel of the respective device. PLMA was inserted in Group P (n = 44) and AQB was inserted in Group A (n = 44) to secure the airway. The primary endpoint was airway seal pressure. Secondarily, we sought to compare overall insertion success, ease of insertion, hemodynamic effects after initial placement, ease of drain tube placement, and perioperative oropharyngolaryngeal morbidity between the devices.

Results:

Oropharyngeal seal pressures for AQB and PLMA were 31.5 ± 2.41 and 29.41 ± 2.14 cm H₂O, respectively (P = 0.01). Insertion time was longer with AQB than PLMA, 25.59 ± 5.71 and 18.66 ± 3.15 seconds, respectively (P = 0.001). Ease and success rate of insertion was better with PLMA compared to AQB. Failure of device insertion was seen in 2 cases of Group A. Gastric distension was seen in 4 patients in Group A, requiring replacement with endotracheal tube in two patients. Ventilation was successful in all 44 patients with PLMA. Both the devices were comparable in providing a patent airway and adequate oxygenation during controlled ventilation. There was an increased trend of airway trauma and complications in the AQB group.

Conclusion:

Both PLMA and AQB show similar efficacy in maintaining ventilation and oxygenation, during laparoscopic surgery. However, proper positioning and functioning of the blocker tube of AQB is a limiting factor, and needs further evaluation.

Air-Q® versus LMA Fastrach™ for fiberoptic-guided intubation: A randomized cross-over manikin trial

INTRODUCTION

Airway management is still a major cause of anesthesia-associated morbidity and mortality. Supraglottic devices are recommended in difficult airway management guidelines. The aim of this study was to compare the performance of the Air-Q^® and the LMA Fastrach™ for fiberoptic guided tracheal intubation.

METHODS

Thirty-three anesthesia trainees participated in this randomized crossover study. Time to insert the dedicated airways (insertion of the airway into the manikin and delivery of two breaths), time to tracheal intubation (fiberoptic-guided tracheal intubation), time to remove the dedicated airway (removal of the Air-Q^®/LMA Fastrach™ over the tracheal tube) and the opinion of the ease of use of the anesthesia trainees were measured.

RESULTS

There was 100% success rate for tracheal intubation with both devices on the first attempt. Time to insert the dedicated device and deliver two breaths was 10±3s for the Air-Q^® and 11±3s for the LMA Fastrach™, P=.07. Time taken to intubate the trachea was shorter with the air-Q^®, 38±15 s, than with the LMA Fastrach™, 47±19s, P=.017. Overall procedure time was significantly shorter with the Air-Q^® as compared with the LMA Fastrach™, with a mean time of 74±21s and 87±28s respectively, P=.002. Air-Q^® removal was considered easier than LMA Fastrach™ removal, P=.005. There were no tube dislodgements during the removal of the dedicated airways.

CONCLUSIONS

Inexperienced anesthesia residents can perform fiberoptic-guided intubation through Air-Q^® and LMA Fastrach™ in a clinically acceptable time with high success.

Comparison of oropharyngeal leak pressure of air-Q™, i-gel™, and laryngeal mask airway supreme™ in adult patients during general anesthesia: A randomized controlled trial

Study Objective:

Various randomized controlled trials and a meta-analysis have compared i-gel™ and laryngeal mask airway Supreme™ (LMA-S™) in adult patients and found that both the devices provided equivalent oropharyngeal leak pressure (OLP). However, no randomized controlled trial has compared air-Q™ with i-gel™ and LMA-S™ in adult patient. Hence, we designed this study to compare air-Q™ with LMA-S™ and i-gel™ in adult patients.

Materials and Methods:

A total of 75 adult patients of the American Society of Anesthesiologists physical status I/II of both sexes, between 18 and 60 years, were included in this prospective randomized controlled trial conducted in a tertiary care center. Randomization of patients was done in three equal groups according to the insertion of supraglottic airway device by a computer-generated random number sequence: group air-Q™ (n = 25), group i-gel™ (n = 25), and group LMA-S™ (n = 25). Primary outcome of this study was OLP. We also recorded time for successful placement of device, ease of device insertion, number of attempts to insert device, and ease of gastric tube insertion along with postoperative complications.

Results:

The mean ± standard deviation OLP of air-Q™, i-gel™, and LMA-S™ was 26.13 ± 4.957 cm, 23.75 ± 5.439 cm, and 24.80 ± 4.78 cm H₂O (P = 0.279). The first insertion success rate for air-Q™, i-gel™, and LMA-S™ was 80%, 76%, and 92%, respectively (P = 0.353). The insertion time of air-Q™, i-gel™, and LMA-S™ was 20.6 ± 4.4, 14.8 ± 5.4, and 15.2 ± 4.7 s, respectively (P = 0.000). Time taken for air-Q™ insertion was significantly higher than time taken for i-gel™ (mean difference 5.8 s, P < 0.0001) and LMA-S™ (mean difference 5.4 s, P = 0.0001) insertion. Postoperative complications were similar with all three devices.

Conclusions:

We concluded that air-Q™, i-gel™, and LMA-S™ were equally efficacious in terms of routine airway management in adult patients with normal airway anatomy.

Comparison of the clinical performances of Air-Qsp and i-Gel for airway management under general anesthesia with a muscle relaxant

STUDY OBJECTIVES

Recently, i-Gel intubating laryngeal airway (ILA) has been frequently used because of the ease for airway insertion by residents and young anesthesiologists. However, it sometimes fails to fit or ventilate sufficiently in Japanese patients. Use of Air-Qsp, which is a new non-inflatable cuffed ILA, in a clinical setting has become possible. The purpose of this study was to compare the clinical performance of Air-Qsp with that of i-Gel for airway management in Japanese adult patients.

DESIGN

A randomized, single-blinded, prospective study was conducted after approval from the institutional review board.

SETTING

Operating rooms at hospitals.

PATIENTS

Thirty-seven adult patients aged 20 to 69 years, with ASA physical status I or II, and scheduled for elective surgery under general anesthesia in the supine position.

INTERVENTIONS

Patients were randomly assigned to insertion with Air-Qsp (Group A: n=20) or i-Gel (Group I: n=17).

MEASUREMENTS

The number of insertions, duration of insertion, changes in systolic blood pressure and heart rate during insertion, delivered tidal volume for setting volume control ventilation, distribution of the tips of the bronchofiberscopes (BFs) on a clock face, and the number of postoperative complications was evaluated.

MAIN RESULTS

Two patients in Group A and one patient in Group I were excluded because insertion of the device failed. There were no significant differences in measured parameters between the 2 groups. The distribution of the tips of the bronchofiberscopes tended to be around the center of the glottis in Group A, whereas they were more toward the 6-o'clock position in Group I.

CONCLUSIONS

Air-Qsp is as useful as i-Gel in Japanese patients and the distributions of the tips of BFs through ILAs are different for Air-Qsp and i-Gel.

Comparative Efficacy of the Air-Q Intubating Laryngeal Airway during General Anesthesia in Pediatric Patients: A Systematic Review and Meta-Analysis

Air-Q® (air-Q) is a supraglottic airway device which can be used as a guidance of intubation in pediatric as well as in adult patients. We evaluated the efficacy and safety of air-Q compared to other airway devices during general anesthesia in pediatric patients by conducting a systematic review and meta-analysis. A total of 10 studies including 789 patients were included in the final analysis. Compared with other supraglottic airway devices, air-Q showed no evidence for a difference in leakage pressure and insertion time. The ease of insertion was significantly lower than other supraglottic airway devices. The success rate of intubation was significantly lower than other airway devices. However, fiberoptic view was better through the air-Q than other supraglottic airway devices. Therefore, air-Q could be a safe substitute for other airway devices and may provide better fiberoptic bronchoscopic view.

Evaluation of glottic view through Air-Q Intubating Laryngeal Airway in the supine and lateral position and assessing it as a conduit for blind endotracheal intubation in children in the supine position

INTRODUCTION

We assessed the feasibility of blind orotracheal intubation in children using the Air-QILA as a conduit in supine position and the glottic view grading by fiberoptic bronchoscope (FOB) through it both in supine and lateral positions.

METHODS

After ethical approval and consent, 60 children were enrolled in the study. In the operating room, after attaching standard monitors to all children, anesthesia was induced with sevoflurane (2-8%) in oxygen (100%). Once the children became sedated, an i.v. access was established and injection glycopyrrolate (10 μg · kg(-1)), fentanyl (2 μg · kg(-1)), and atracurium (0.5 mg · kg(-1)) were administered. After 3 min, the Air-QILA was placed in supine position and glottic view was assessed by using FOB, in supine and right lateral decubitus position. In all children, gradings of glottic view in two different positions were noted. After that all children were turned supine, and orotracheal intubation was done blindly through the Air-QILA. The success rate, insertion time of the Air-QILA, and endotracheal intubation were noted.

RESULTS

The Air-QILA placement was successful in 57 children in first attempt and three children required second attempt. However, blind endotracheal intubations through the Air-QILA were successful in 38 children in first attempt and 12 children required second attempt. In the remaining 10 children, where blind endotracheal intubation through the Air-QILA remained unsuccessful, conventional laryngoscopy was performed. In supine and lateral positions, Grade 1 glottic view was seen in 41 and 38 of total 60 patients, respectively. Turning of all children from supine to lateral decubitus position resulted in the deterioration of grading of glottic view in eight children and improvement in two children (P = 0.001).

CONCLUSION

The Air-QILA is an easy to place supraglottic airway device with excellent airway seal and low airway morbidity. It may be useful as a conduit for blind orotracheal intubation in supine position and can be used as an effective alternative to FOB in low resource settings.

Comparisons of clinical performance of Guardian laryngeal mask with laryngeal mask airway ProSeal

Background

The Guardian Laryngeal Mask Airway (G-LMA) is a new silicone-based single-use extraglottic device with the drainage port and a cuff pilot valve with pressure indicator. The aim of this study is to compare the clinical performance of this laryngeal mask airway with ProSeal laryngeal mask airway (P-LMA).

Methods

In this prospective randomized study, we included adult patients with ASA grading I and II scheduled for elective surgery requiring supine position under total intravenous anesthesia. The patients were randomly allocated to two groups, 40 in each. G-LMA and P-LMA were used in groups G and P respectively. The cuff of each device was air inflated to 60 cmH₂O. The primary outcome was to compare the airway sealing pressure and the secondary outcome was to compare the efficacy and safety of these two devices with respect to insertion success, insertion time, ease of insertion, volume of air for cuff inflation to 60 cmH₂O, intracuff pressure measurement, gastric tube insertion attempt, gastric tube insertion time, Fiberoptic laryngeal view, and postoperative pharyngolaryngeal morbidity.

Results

The airway sealing pressure at 60cmH₂O cuff pressure was significantly greater in G-LMA than P-LMA (p = 0.04).The first successful attempt of both groups were comparable (p = 1.000). Insertion time was significantly shorter in G-LMA than P-LMA (p < 0.0001). The first successful attempt for the gastric tube insertion in both groups was comparable (p = 0.431). Gastric tube insertion time was less in G-LMA than in P-LMA (p < 0.0001). The volume of air for cuff inflation to 60 cmH₂O was more in G-LMA than in P-LMA (<0.0001). The intracuff pressure measurement at 30, 60, 90 and 120 minutes were comparable (p = 0.823, 0.182, 0.870, 0.658).We did not find differences in ease of insertion (p = 0.60); Fiber-optic positions of airway devices were comparable (p = 0.83). In addition, blood staining (p = 1.00), sore throat and dysphagia at 1, 2 and 24 hour (p = 1.00) were comparable in both groups.

Conclusion

The Guardian laryngeal mask airway was associated with high airway sealing pressure with a quicker insertion of the device as well as gastric tube.

Trial registration

Clinical Trial.gov Identifier: NCT02063516. Date: June 2013

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-015-0039-3) contains supplementary material, which is available to authorized users.

The self-pressurising air-Q® Intubating Laryngeal Airway for airway maintenance during anaesthesia in adults: a report of the first 100 uses

The self-pressurising air-Q® Intubating Laryngeal Airway is a new, commercially available, supraglottic airway device that incorporates a self-regulating periglottic cuff. In this retrospective review, we describe our initial clinical experience using the device in 100 patients. The ease and number of insertion attempts, airway seal pressure, device positioning, intubation success and oropharyngeal morbidity were recorded. The air-Q Intubating Laryngeal Airway was successfully inserted in all 100 patients and functioned adequately as a primary airway in 70 of the 72 patients in which it was used for this purpose. The median (interquartile range [range]) airway seal pressure was 22 (19-29, [10-40]) cmH2O. Intubation via the air-Q Intubating Laryngeal Airway was successful in 28 of 29 (97%) patients. Eleven percent of patients complained of sore throat postoperatively before discharge. In our series, the air-Q Intubating Laryngeal Airway performed adequately as a primary airway during anaesthesia with respect to ease of insertion, adequacy of airway maintenance and as a conduit for intubation in both anticipated and unanticipated difficult airways. Although our initial experience is positive, further investigation with larger numbers of observations are needed as the upper limits of the 95% confidence intervals for device failure (the worst failure rate the clinician could expect) are still high.

Validation of the unassisted, gum-elastic bougie-guided, laryngeal mask airway-ProSeal™ placement technique in anaesthetized patients

AIMS

The laryngeal mask airway-ProSeal™ can be inserted digitally, by introducer tool, or by railroading it over a bougie placed first in the patient's oesophagus, which is highly successful, but as originally described, requires an assistant. An unassisted bougie-guided placement technique has also been described, but no data on its effectiveness have been reported.

METHODS

We reviewed data collected during a randomized, controlled trial comparing the air-Q(®) Intubating Laryngeal Airway and LMA-Proseal™, in which all LMA-Proseal™ devices were inserted using the unassisted (one-operator), bougie-guided placement technique.

RESULTS

Forty-eight devices were placed. All devices were placed successfully. Successful placement was achieved in 47 (98%) patients on first attempt and in one (2%) patient on the third attempt. Mean (SD) time required for insertion establishing ventilation was 28 (11) s. Mean (SD) airway seal pressure was 30 (6) cmH(2)O. Gross blood was found on four (8%) devices upon removal, but no oropharyngeal injuries were noted on oral exam in the recovery unit prior to discharge. The most common complaints in recovery and 24 h post-operatively were sore throat [discharge: mild = 18/48 (38%); 24 h: mild = 9/38 (19%), moderate = 1/38 (3%)] and pain on swallowing [discharge: mild = 7/48 (15%); 24 h: mild = 2/38 (6%)].

CONCLUSIONS

Our data confirm that in experienced hands, bougie-guided placement of the LMA-Proseal™ without the aid of an assistant can be accomplished quickly and successfully without affecting the expected clinical performance of the device.