Airway management evolution - in a search for an ideal extraglottic airway device

Does Baska mask deserve its own niche among extraglottic airway devices? A prospective, single-arm study

Background and Aims

A variety of extraglottic airway devices (EADs) are available. Main concerns with EADs are protection against aspiration and ability to ventilate patients with high airway pressures. Baska mask meets these criteria and is the only third-generation device available for clinical use.

Methods

After institutional ethics committee approval and informed consent were obtained, this prospective study was performed in 100 adult patients undergoing surface surgeries at a tertiary referral centre. The primary outcome was the success rate of insertion, while the secondary outcomes were the sealing pressure, stability of the device and the perioperative complications of Baska mask. We then compared it with other currently used EADs.

Results

The first attempt at insertion and overall success rates, showed values of 81% and 98%, respectively. Insertion was quick (median 12; interquartile range [IQR] 9-15 s). The mask sealing pressure, was 35 cmH2O (median [IQR 20-50 cmH2O]). Also, the mask remained stable in 95% of patients intraoperatively. Sore throat and dysphagia were seen in 37% and 24% of patients, respectively. No patient had laryngospasm or desaturation at any time. It compared favourably well with other EADs, while achieving higher sealing pressures.

Conclusion

We found that the Baska mask performs well with excellent first attempt at insertion and overall success rates, higher sealing pressures and minimal complications compared to currently used EADs in clinical anaesthesia.

Comparison of the third-generation streamlined liner of the pharynx airway (SLIPA-3G) with the laryngeal mask airway supreme for laparoscopic cholecystectomy: a randomized prospective study

Background

The third-generation streamlined liner of the pharynx airway (SLIPA-3G) is a new-generation supraglottic airway device (SAD) that is non-cuffed and disposable, with a sealing pressure that varies dynamically with the airway pressure. This study compared the SLIPA-3G with the laryngeal mask airway supreme (LMAS) in patients undergoing laparoscopic cholecystectomy.

Methods

Two hundred and twenty patients scheduled for laparoscopic cholecystectomy were randomly allocated to either the SLIPA-3G group or the LMAS group. Data were collected on the patients’ hemodynamic parameters at different time points, ease of insertion, fiberoptic view, oropharyngeal leak pressure (OLP) at different time points and SAD-related complications.

Results

The mean OLP immediately after device placement in the LMAS group was significantly higher than that of the SLIPA-3G group (31.34 ± 6.99 cmH₂O vs.28.94 ± 6.01 cmH₂O, P = 0.008, 95% CI 0.62–4.17). The OLPs of the two groups were not significantly different after the induction of a pneumoperitoneum until the end of surgery. The OLP increased gradually through the course of the operation in the SLIPA-3G group (P value = 0.035) but not in the LMAS group (P value = 0.945). There was no significant difference between the two groups in hemodynamic parameters, insertion time and success rate, fiberoptic view and complication rate.

Conclusions

The SLIPA-3G and LMAS were associated with comparable OLPs, hemodynamic parameters, ease of insertion, fiberoptic views and complication rates when used during laparoscopic cholecystectomy. The SLIPA-3G can be used as an effective alternative to the LMAS in patients undergoing laparoscopic surgeries.

Evaluation of the insertion parameters and complications of the i-gel Plus airway device for maintaining patent airway during planned procedures under general anaesthesia: a protocol for a prospective multicentre cohort study

INTRODUCTION

Supraglottic airway devices represent a less invasive method of airway management than tracheal intubation during general anaesthesia. Their continued development is focused mainly on improvements in the insertion success rate and minimalisation of perioperative and postoperative complications. The i-gel Plus is a novel, anatomically preshaped supraglottic airway device which achieves a perilaryngeal seal due to a non-inflatable cuff made of a soft thermoplastic elastomer. The purpose of this cohort study is to assess the success rate of the i-gel Plus use during elective procedures under general anaesthesia, its intraoperative performance, and the degree of postoperative complications.

METHODS AND ANALYSIS

This is a multicentre, prospective, interventional cohort study. The enrolment will take place in seven centres in four European countries. We plan to enrol 2000 adult patients in total, who are scheduled for elective surgery under general anaesthesia, and with an indication for use of a supraglottic airway device for management of their airway. The study is projected to run over a period of 18 months. The primary outcome of the study is the total success rate of the i-gel Plus insertion in terms of successful ventilation and oxygenation through the device. Secondary outcomes include perioperative parameters, such as insertion time, seal/leak pressures, number of insertion attempts and postoperative adverse events and complications. Postoperative follow-up will be performed at 1 hour, 24 hours in all patients, and for selected patients at 3 and 6 months.

ETHICS AND DISSEMINATION

The cohort study has received the following ethical approvals: General University Hospital Prague, University Hospital Olomouc, University Military Hospital Prague, University Hospital Barcelona, University Hospital Lodz, Antrim Area Hospital, Craigavon Area Hospital, Office for Research Ethics Committees Northern Ireland. The results will be published in peer-reviewed journals and presented at relevant anaesthesia conferences.

TRIAL REGISTRATION NUMBER

ISRCTN86233693;Pre-results.

Ultrasound comparison of external and internal neck anatomy with the LMA Unique

Introduction

Internal neck anatomy landmarks and their relation after placement of an extraglottic airway devices have not been studied extensively by the use of ultrasound. Based on our group experience with external landmarks as well as internal landmarks evaluation with other techniques, we aimed use ultrasound to analyze the internal neck anatomy landmarks and the related changes due to the placement of the Laryngeal Mask Airway Unique.

Methods

Observational pilot investigation. Non-obese adult patients with no evidence of airway anomalies, were recruited. External neck landmarks were measured based on a validated and standardized method by tape. Eight internal anatomical landmarks, reciprocal by the investigational hypothesis to the external landmarks, were also measured by ultrasound guidance. The internal landmarks were re-measured after optimal placement and inflation of the extraglottic airway devices cuff Laryngeal Mask Airway Unique.

Results

Six subjects were recruited. Ultrasound measurements of hyoid-mental distance, thyroid-cricoid distance, thyroid height, and thyroid width were found to be significantly (p < 0.05) overestimated using a tape measure. Sagittal neck landmark distances such as thyroid height, sternal-mental distance, and thyroid-cricoid distance significantly decreased after placement of the Laryngeal Mask Airway Unique.

Conclusion

The laryngeal mask airway Unique resulted in significant changes in internal neck anatomy. The induced changes and respective specific internal neck anatomy landmarks could help to design devices that would modify their shape accordingly to areas of greatest displacement. Also, while external neck landmark measurements overestimate their respective internal neck landmarks, as we previously reported, the concordance of each measurement and their respective conversion factor could continue to be of help in sizing extraglottic airway devices. Due to the pilot nature of the study, more investigations are warranted.

Extraglottic airway devices: technology update

Extraglottic airway devices (EADs) have revolutionized the field of airway management. The invention of the laryngeal mask airway was a game changer, and since then, there have been several innovations to improve the EADs in design, functionality, safety and construction material. These have ranged from changes in the shape of the mask, number of cuffs and material used, like rubber, polyvinylchloride and latex. Phthalates, which were added to the construction material in order to increase device flexibility, were later omitted when this chemical was found to have serious adverse reproductive outcomes. The various designs brought out by numerous companies manufacturing EADs resulted in the addition of several devices to the airway market. These airway devices were put to use, many of them with inadequate or no evidence base regarding their efficacy and safety. To reduce the possibility of compromising the safety of the patient, the Difficult Airway Society (DAS) formed the Airway Device Evaluation Project Team (ADEPT) to strengthen the evidence base for airway equipment and vet the new extraglottic devices. A preuse careful analysis of the design and structure may help in better understanding of the functionality of a particular device. In the meantime, the search for the ideal EAD continues.

The i-gel Supraglottic Airway as a Conduit for Fibreoptic Tracheal Intubation – A Randomized Comparison with the Single-use Intubating Laryngeal Mask Airway and CTrach Laryngeal Mask in Patients with Predicted Difficult Laryngoscopy

Fibreoptic intubation through a supraglottic airway is an alternative plan for airway management in difficult or failed laryngoscopy. The aim of this study was to compare three supraglottic airways as conduits in patients with at least one predictor for difficult laryngoscopy. The i-gel was compared with the single-use intubating laryngeal mask airway (sILMA) and CTrach laryngeal mask in 120 adult patients scheduled for elective surgeries under general anaesthesia using a prospective, randomized and single-blinded design. Primary outcome was success rate of tracheal intubation through the device, while secondary outcomes were times required for device insertion and tracheal tube placement, fibreoptic scores and the incidence of perioperative complications and postoperative complaints. The success rates showed no statistical difference between devices (i-gel 100%, CTrach 97.5%, ILMA 95%). Insertion time was shortest for the i-gel (12.4 s) compared with ILMA (19.3 s) and CTrach (24.4 s). Intubation time was shorter in the i-gel group (29.4 s) in comparison with the CTrach (39.8 s, p<0.05) and sILMA (51.9 s, p<0.001) groups. Best fibreoptic scores were observed also in the i-gel group. In total, 24 patients (20%) presented with difficult laryngoscopy. The i-gel showed significantly shorter times for insertion and fibreoptic intubation than the other two devices in this group. No difference was observed in the incidence of postoperative complaints. The i-gel is a suitable alternative to the sILMA and CTrach for fibrescope-guided tracheal intubation. Shorter insertion and intubation times with the i-gel may provide advantage in case of difficult oxygenation.

Complications Associated with the Use of Supraglottic Airway Devices in Perioperative Medicine

Supraglottic airway devices are routinely used for airway maintenance in elective surgical procedures where aspiration is not a significant risk and also as rescue devices in difficult airway management. Some devices now have features mitigating risk of aspiration, such as drain tubes or compartments to manage regurgitated content. Despite this, the use of these device may be associated with various complications including aspiration. This review highlights the types and incidence of these complications. They include regurgitation and aspiration of gastric contents, compression of vascular structures, trauma, and nerve injury. The incidence of such complications is quite low, but as some carry with them a significant degree of morbidity the need to follow manufacturers' advice is underlined. The incidence of gastric content aspiration associated with the devices is estimated to be as low as 0.02% with perioperative regurgitation being significantly higher but underreported. Other serious, but extremely rare, complications include pharyngeal rupture, pneumomediastinum, mediastinitis, or arytenoid dislocation. Mild short-lasting adverse effects of the devices have significantly higher incidence than serious complications and involve postoperative sore throat, dysphagia, pain on swallowing, or hoarseness. Devices may have deleterious effect on cervical mucosa or vasculature depending on their cuff volume and pressure.