Comparação da máscara laríngea i‐gel (i‐gel™) com a máscara laríngea clássica (LMA‐Classic™) em relação ao desempenho clínico

Evaluation of Four Techniques to Administer Laryngeal Mask Airway

Background

Laryngeal mask airway (LMA) plays a crucial role in the field of modern anesthesia. There are different techniques to administer LMA. Here we aimed to compare the four methods of standard, 90° rotation, 180° rotation, and thumb placement in LMA mast placement.

Materials and Methods

This is a clinical trial that was performed on 257 candidates of elective surgical operations requiring general anesthesia. All patients were categorized into four groups of LMA placement with index finger (standard method), mask placement with 90° rotation, 180° rotation method, and thumb finger group. We collected data regarding the success rates of LMA placement, the need for any manipulation when placing the mask, LMA placement time, failure of mask placement, presence of blood on the LMA, and laryngospasm and sore throats 1 hour after surgery in patients.

Results

The 90° rotation method had a significantly higher first attempt success rate than that in the other three methods (98.4%, P = 0.02). Total success rate in 90° rotation method was also significantly higher than the other techniques (100%, P < 0.001). The need for any manipulation when placing the mask (1.6%, P = 0.01), presence of blood on the LMA mask (1.6%, P = 0.33), and frequency of sore throats 1 hour after surgery (21.9%, P = 0.14) were also lower in 90° rotation method than that in the other methods.

Conclusion

The 90° rotation method had significantly higher success rate and lower failure rate regarding the mask placement compared to other three methods.

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.

Supraglottic Airway Devices for Elective Pediatric Anesthesia: I-gel versus Air-Q, Which is the Best?

Objectives:

The objectives of the study were to compare the insertion facility, the effect on hemodynamic parameters, and effective ventilation using I-gel versus Air-Q supraglottic airway devices (SADs) for pediatric patients undergoing short-duration surgical procedures.

Patients and Methods:

One hundred and fifty children aged 3–10 years were randomly divided into two equal groups: Group I received I-gel and Group Q received Air-Q SAD. All patients were anesthetized by sevoflurane inhalation using a face mask without neuromuscular blockade. Study outcomes included SAD insertion success rate (SR), insertion time, anatomic alignment of the SAD to the larynx as judged using fiberoptic bronchoscope (FOB) inserted through the SAD, and tidal volume leak, and incidence of postoperative complications.

Results:

Total and first attempt SRs were 97.3% and 85.3% for I-gel and 94.7% and 82.7% respectively, for Air-Q with nonsignificant differences. However, I-gel insertion time (12.3 ± 3.6 s.) was significantly (P = 0.034) shorter than Air-Q (13.7 ± 4.2 s). FOB grading of laryngeal view through SAD was better with I-gel but without significant difference for patients who had view Grades 1-2. Percentage of tidal volume loss was significantly decreased at 5 min after insertion than immediately after insertion, in all patients, with a nonsignificant difference in favor of I-gel. Intraoperative hemodynamic changes and postoperative complications showed a nonsignificant difference between both the groups.

Conclusion:

Both Air-Q and I-gel SAD provided advantages for pediatric anesthesia during short-duration surgical procedure with nonsignificant differences. However, I-gel SAD required a shorter insertion time and provided a high SR which is satisfactory for trainees and during an emergency. I-gel SAD allowed minimization of tidal volume leak and gastric inflation and is associated with infrequent complications.

[Effect of different training methods on the use of the i-gel laryngeal mask by lay persons on a manikin]

BACKGROUND

Several studies have described the successful application of extraglottic airways by lay people to a phantom.

OBJECTIVES

This study examined the influence of the training method on the success of the application.

METHODS

A total of 150 visitors of a shopping mall were asked to place an i‑gel laryngeal mask (Intersurgical GmbH, Sankt Augustin, Germany) on a manikin. The short instruction was randomized and performed either as a practical demonstration or through the self-study of an illustrated manual.

RESULTS

Application success in the first attempt was 95.8 % for the practical demonstration group and 78.5 % for the written instruction group (p = 0.001). Placement times were also significantly different (median 11.5 s vs. 22.5 s, p < 0.001).

CONCLUSIONS

Learning success can be achieved with both training methods. Initially, a hands-on training should be carried out with a practical demonstration.

Nonintubated Tracheal Surgery

The article describes an anesthetic management strategy for resection of the cervical trachea due to benign stenosis without using an endotracheal tube. The strategy includes: (1) insertion of an airway stent in the stenotic area, (2) insertion of a supraglottic airway device (SGAD), and (3) advancing a jet ventilation catheter through the SGAD. The stent is removed during surgery together with the resected part of the trachea. The technique of nonintubated tracheal resection allows the surgeon to work most comfortably and helps the anesthesiologist properly maintain the patient's vital functions in the operating room.

Application of lower limb nerve block combined with slow induction of light general anesthesia and tracheal induction in elderly hip surgery

BACKGROUND

This study aims to evaluate the effectiveness and safety of lower limb nerve block combined with slow induction of light general anesthesia and tracheal intubation in hip surgery in the elderly.

METHODS

Thirty elderly patients who underwent hip surgery under the lower limb nerve block were randomly divided into 2 groups: slow induction of light general anesthesia and tracheal intubation group (group M), and laryngeal mask light general anesthesia group (group H). After undergoing total intravenous anesthesia without muscle relaxants, all patients received sciatic nerve, lumbar plexus, and paravertebral nerve blocks. The hemodynamic situations, dosage of anesthetics, time for awakening and extubation (or laryngeal mask removal), and incidence of respiratory adverse reactions in the induction period were recorded.

RESULTS

Compared with baseline levels, the difference in mean arterial pressure (MAP) value at each time point after intubation/laryngeal mask removal in both groups was not statistically significant (P > .05). Furthermore, the time for awakening and extubation/laryngeal mask removal, and anesthetic dosage were significantly decreased in group M, when compared with group H (P < .05). For the incidence of adverse reactions, the incidence of poor sealing and hypoxia was significantly lower in group M than in group H (P < .05), and the incidence of sore throat was significantly lower in group H than in group M (P < .05).

CONCLUSION

Lower limb nerve block combined with slow induction of light general anesthesia and tracheal intubation was associated with smaller anesthetic dosage, and shorter duration of anesthesia induction and extubation/laryngeal mask after surgery.

Comparison of the clinical performance of i-gel, LMA Supreme and LMA ProSeal in elective surgery

INTRODUCTION

The LMA Supreme™, i-gel® and LMA ProSeal™ are second-generation supraglottic airway devices. We tested the hypothesis that these devices differ in performance when used for spontaneous ventilation during anaesthesia.

METHODS

150 patients who underwent general anaesthesia for elective surgery were randomly allocated into three groups. Data was collected on oropharyngeal leak pressures, ease and duration of device insertion, ease of gastric tube insertion, and airway safety.

RESULTS

Leak pressure, our primary outcome measure, was found to be higher for the i-gel than the Supreme and ProSeal (mean ± standard error of the mean: 27.31 ± 0.92 cmH2O, 23.60 ± 0.70 cmH2O and 24.44 ± 0.70 cmH2O, respectively; p = 0.003). Devices were inserted on the first attempt for 90%, 82% and 72% of patients in the i-gel, Supreme and ProSeal groups, respectively (p = 0.105); mean device placement times were 23.58 seconds, 25.10 seconds and 26.34 seconds, respectively (p = 0.477). Gastric tubes were inserted on the first attempt in 100% of patients in the Supreme group, and 94% of patients in the i-gel and ProSeal groups (p = 0.100). There was blood staining on removal in 9 (18%) patients in each of the Supreme and ProSeal groups, with none in the i-gel group (p = 0.007). The incidence of postoperative sore throat, dysphagia and hoarseness was lowest for the i-gel.

CONCLUSION

The three devices were comparable in terms of ease and duration of placement, but the i-gel had higher initial oropharyngeal leak pressure and lower airway morbidity compared with the ProSeal and Supreme.

Comparison of remifentanil EC50 for facilitating i-gel and laryngeal mask airway insertion with propofol anesthesia

OBJECTIVE

Each supraglottic airway requires different anesthetic depth because it has a specific structure and different compressive force in the oropharyngeal cavity. We designed the study to compare the effect-site concentration (Ce) of remifentanil in 50 % of patients (EC50) for successful insertion of the i-gel second-generation supraglottic airway device with that for laryngeal mask airway (LMA) insertion during target-controlled infusion (TCI) of propofol.

METHODS

Forty-one female patients were randomized to the i-gel group (n = 20) or the LMA group (n = 21). Anesthesia was induced with propofol Ce of 5 μg/ml and the predetermined remifentanil Ce, and the i-gel or LMA was inserted 5 min later. The remifentanil Ce was estimated by modified Dixon's up-and-down method (initial concentration: 3.0 ng/ml, step size: 0.5 ng/ml). The patient's response to device insertion was classified as either "success (no movement)" or "failure (movement)".

RESULTS

Using the Dixon's up-and-down method, EC50 of remifentanil Ce for the i-gel (1.58 ± 0.41 ng/ml) was significantly lower than that for LMA (2.25 ± 0.55 ng/ml) (p = 0.038). Using isotonic regression, EC50 (83 % CI) of remifentanil in the i-gel group [1.50 (1.37-1.80) ng/ml] was statistically lower than that in the LMA group [2.00 (1.82-2.34) ng/ml]. EC95 (95 % CI) of remifentanil in the i-gel group [2.38 (1.48-2.50) ng/ml] was statistically lower than that in the LMA group [3.35 (2.58-3.48) ng/ml].

CONCLUSIONS

We found that EC50 of remifentanil Ce for i-gel insertion (1.58 ng/ml) was significantly lower than that for LMA insertion (2.25 ng/ml) in female patients during propofol TCI without neuromuscular blockade.