A comparison of the disposable Ambu�AuraOnce?Laryngeal Mask with the reusable LMA Classic?laryngeal mask airway

Comparison of the ED50 propofol requirements during the insertion of laryngeal mask airway Ambu AuraFlex with Ambu AuraOnce in children undergoing strabismus surgery

WHAT IS KNOWN AND OBJECTIVE

Optimal airway management is crucial in strabismus surgery due to the inaccessibility of the airway throughout the procedure. Laryngeal mask airway offers advantages over tracheal intubation in ophthalmic surgery as it does not increase the intraocular pressure. The purpose of this study was to determine the median effective dose of propofol required, when combined with 0.2 µg/kg of sufentanil, for smooth insertion of Ambu AuraFlex in the first attempt in children undergoing strabismus surgery, and to compare it with that for Ambu AuraOnce.

METHODS

Forty-three paediatric patients undergoing strabismus surgery under general anaesthesia were recruited. For induction, the initial dosage of propofol was 2 mg/kg in the AuraOnce group or 3 mg/kg in the AuraFlex group. In accordance with Dixon's up-and-down method, the dose of propofol for consecutive patients in each group was adjusted in increments or decrements of 0.25 mg/kg based on the previous patient's "three-point, six-category scale" response to the first attempt of insertion of the randomized device. Insertion of the device was attempted when the bispectral index was ≤60 for 5 s after propofol administration without the use of neuromuscular blocking agents.

RESULTS AND DISCUSSION

The median effective dose (95% confidence interval) of propofol was significantly lower in the Ambu AuraOnce group than in the Ambu AuraFlex group (1.92 [1.50-2.32] mg/kg vs. 2.98 [2.49-3.94] mg/kg; p = 0.002). The incidence of dislodgement of the device was significantly higher with the use of the Ambu AuraOnce than with the use of AuraFlex (p = 0.023), whereas insignificant differences were observed between the two groups in the incidence of other perioperative adverse events.

WHAT IS NEW AND CONCLUSION

Ambu AuraFlex requires a significantly higher dose of propofol for insertion and provides more effective and stable airway management in strabismus surgery than AuraOnce.

[Comparison of two supraglottic airway devices on postoperative sore throat in children: a prospective randomized controlled trial]

BACKGROUND AND OBJECTIVE

Sore throat is well recognized complaint after receiving general anesthesia. This study is conducted to compare the severity and frequency of postoperative sore throat in children undergoing elective surgery - following the use of Ambu laryngeal mask airway) or I-gel® - who are able to self-report postoperative sore throat.

METHOD

Seventy children, 6 to 16 years-old, undergoing elective surgery randomly allocated to either Ambu laryngeal mask (Ambu Group) or I-gel® (I-gel Group). After the procedure, patients were interviewed in the recovery room immediately, after one hour, 6 and 24 hours postoperatively by an independent observer blinded to the device used intra-operatively.

RESULTS

On arrival in the recovery room 17.1% (n=6) of children of the Ambu Group complained of postoperative sore throat, against 5.7% in I-gel Group (n=2). After one hour, the results were similar. After 6 hours, postoperative sore throat was found in 8.6% (n=3) of the children in Ambu group vs. 2.9% (n=1) in I-gel Group. After 24hours, 2.9% (n=1) of the kids in Ambu Group compared to none in I-gel Group. There was no significant difference found in the incidence of postoperative sore throat in both devices on arrival (p=0.28); after 1 hour (p=0.28); after 6 hours (p=0.30); and after 24 hours (p=0.31). The duration of the insertion was shorter in Ambu Group and it was easier to insert the I-gel® (p=0.029). Oropharyngeal seal pressure of I-gel® was higher than that of Ambu laryngeal mask (p=0.001).

CONCLUSION

The severity and frequency of postoperative sore throat in children is not statistically significant in the I-gel Group compared to Ambu Group.

Comparison of two supraglottic airway devices on postoperative sore throat in children: a prospective randomized controlled trial

Background and objective

Sore throat is well recognized complaint after receiving general anesthesia. This study is conducted to compare the severity and frequency of postoperative sore throat in children undergoing elective surgery, following the use of Ambu laryngeal mask airway or I-gel®, who are able to self-report postoperative sore throat.

Method

Seventy children, 6 to 16 years-old, undergoing elective surgery randomly allocated to either Ambu laryngeal mask (Ambu Group) or I-gel® (I-gel Group). After the procedure, patients were interviewed in the recovery room immediately, after one hour, 6 and 24 hours postoperatively by an independent observer blinded to the device used intra-operatively.

Results

On arrival in the recovery room 17.1% (n = 6) of children of the Ambu Group complained of postoperative sore throat, against 5.7% in I-gel Group (n = 2). After one hour, the results were similar. After 6 hours, postoperative sore throat was found in 8.6% (n = 3) of the children in Ambu group vs. 2.9% (n = 1) in I-gel Group. After 24 hours, 2.9% (n = 1) of the children in Ambu Group complained of postoperative sore throat compared to none in I-gel Group. There was no significant difference found in the incidence of postoperative sore throat in both devices on arrival (p =  0.28); after 1 hour (p =  0.28); after 6 hours (p =  0.30); and after 24 hours (p =  0.31). The duration of the insertion of Ambu laryngeal mask was shorter and it was easier to insert than I-gel® (p =  0.029). Oropharyngeal seal pressure of I-gel® was higher than that of Ambu laryngeal mask (p =  0.001).

Conclusion

The severity and frequency of postoperative sore throat in children is not statistically significant in the I-gel Group compared to Ambu Group.

Comparative study of the Ambu® AuraOnce™ laryngeal mask and endotracheal intubation in anesthesia airway management during neurosurgery

Objective

To investigate the feasibility and efficacy of the Ambu® AuraOnce™ laryngeal mask (LMA) compared with endotracheal intubation (ETI) during supratentorial tumor resection in the right lateral decubitus position.

Methods

This was a randomized controlled trial of LMA compared with ETI in patients who were scheduled to undergo supratentorial tumor resection in the right lateral decubitus position. The patients were randomized to the LMA (n = 40) and ETI groups (n = 40). The hemodynamic parameters (primary outcome) and mechanical ventilation parameters, anesthetic dose, and complications as well as quality of anesthesia recovery (secondary outcomes) were compared.

Results

Patients in the LMA group exhibited lower mean arterial pressure (MAP) and heart rate (HR) compared with ETI. Nine and two patients received esmolol during intubation and extubation, respectively. The airway pressure (AP) in the LMA group was higher compared with the ETI group 60 minutes after the start of surgery. Compared with the ETI group, the sufentanil dose was lower by 24% and the anesthesia recovery rate was better in the LMA group.

Conclusions

LMA can improve hemodynamic stability in patients undergoing supratentorial tumor resection in the right lateral decubitus position. If there is a clinical need and no contraindication, LMA could replace ETI.

Pediatric supraglottic airway devices in clinical practice: A prospective observational study

BACKGROUND

Supraglottic airway devices (SGA) are commonly used in pediatric anesthesia and serve as primary or back-up devices for difficult airway management. Most SGA are marketed without proper clinical evaluation. The purpose of this study was to evaluate the performance of the pediatric LMA Supreme™, Air-Q® and Ambu® Aura-i™.

METHODS

This prospective observational study was performed at Bern University Hospital, Switzerland. With ethics committee approval and a waiver for written informed consent 240 children undergoing elective surgery with an ASA class I-III and a weight of 5-30 kg were included. Three different pediatric supraglottic airway devices were assessed: The LMA Supreme™, Air-Q® and Ambu® Aura-i™. Primary outcome parameter was airway leak pressure. Secondary outcome parameters included first attempt and overall success rate, insertion time, fiberoptic view through the SGA, and adverse events. The primary hypothesis was that the mean airway leak pressure of each tested SGA was 20 cmH₂O ± 10%.

RESULTS

None of the SGA showed a mean airway leak pressure of 20 cmH₂O ± 10%, but mean airway leak pressures differed significantly between devices [LMA Supreme™ 18.0 (3.4) cmH₂O, Air-Q® 15.9 (3.2) cmH₂O, Ambu® Aura-i™ 17.3 (3.7) cmH₂O, p < 0.001]. First attempt success rates (LMA Supreme™ 100%, Air-Q® 90%, Ambu® Aura-i™ 91%, p = 0.02) and overall success rates (LMA Supreme™ 100%, Air-Q® 91%, Ambu® Aura-i™ 95%, p = 0.02) also differed significantly. Insertion times ranged from 20 (7) seconds (Air-Q®) to 24 (6) seconds (LMA Supreme™, <p = 0.005). Insertion was rated easiest with the LMA Supreme™ (very easy in 97% vs. Air-Q® 70%, Ambu® Aura-i™ 72%, p < 0.001). Fiberoptic view was similar between the SGA. Adverse events were rare.

CONCLUSIONS

Airway leak pressures ranged from 16 to 18 cmH₂O, enabling positive pressure ventilation with all successful SGA. The highest success rates were achieved by the LMA Supreme™, which was also rated easiest to insert.

TRIALS REGISTRATION

ClinicalTrials.gov , identifier NCT01625858 . Registered 31 May 2012.

The AMBU® Aura-i™ Laryngeal Mask and LMA Supreme™: A Randomized Trial of Clinical Performance and Fibreoptic Positioning in Unparalysed, Anaesthetised Patients by Novices

Introduction. Manikin studies' data cannot accurately be extrapolated to real-life scenarios and inherent differences in design and materials of newer products may affect their clinical performance. Methods. Hence, we compared the AMBU® Aura-i™ and LMA Supreme™ in this randomized trial involving 100 ASA 1-2 unparalysed anaesthetised patients undergoing minor gynaecological surgery. Investigators had <20 Aura-i insertions. Primary outcome was time to achieve effective ventilation and secondarily insertion parameters, oropharyngeal leak pressures (OLP), fibreoptic positioning, and pharyngeal morbidity. The position of the Ambu Aura-i was evaluated with the Ascope; the fiberoptic view of the glottis was scored on a five-point scale. Results. 43 (86%) AMBU Aura-i and 44 (88%) LMA Supremes were successfully inserted on first attempt (p = 0.59), with similar ease (p = 0.79), and comparable times to first capnogram, mean (SD) 18.2 (6.0) versus 17.3 (6.4) sec, p = 0.9. The Aura-i needed significantly less volume of air to inflate its cuff to 60 cmH₂O on the manometer, 17.7 (3.5) versus 23.1 (4.4) mL, p < 0.001. Both devices exhibited similar OLP, Aura-i versus LMA Supreme, mean (SD) 28.8 (7.1) versus 27.3 (5.3) cmH₂O, p = 0.24. There was no difference in ease of insertion or adjustment manoeuvres to aid ventilation. 90% of patients had good positioning of Aura-i on fibreoptic check, yielding a view of the vocal cords and epiglottis. In 5 patients (10%), the vocal cords were not seen, but ventilatory function was unaffected. Conclusions. The Aura-i handled well in novices hands, with comparable times to insert and establish ventilation, similar leak pressures, and successful first attempt insertion rates compared to the LMA Supreme.

Extraglottic airway devices: A review

Extraglottic airway devices (EAD) have become an integral part of anesthetic care since their introduction into clinical practice 25 years ago and have been used safely hundreds of millions of times, worldwide. They are an important first option for difficult ventilation during both in-hospital and out-of-hospital difficult airway management and can be utilized as a conduit for tracheal intubation either blindly or assisted by another technology (fiberoptic endoscopy, lightwand). Thus, the EAD may be the most versatile single airway technique in the airway management toolbox. However, despite their utility, knowledge regarding specific devices and the supporting data for their use is of paramount importance to patient's safety. In this review, number of commercially available EADs are discussed and the reported benefits and potential pitfalls are highlighted.

Comparison of classic laryngeal mask airway with Ambu laryngeal mask for tracheal tube exchange: A prospective randomized controlled study

Background and Aim:

Exchanging endotracheal tube (ETT) with classic laryngeal mask airway™ (CLMA™) prior to emergence from anaesthesia is a safe technique to prevent the coughing and haemodynamic changes during extubation. We had compared CLMA™ and AMBU laryngeal mask™ (ALM™) during ETT/laryngeal mask (LM) for haemodynamic changes and other parameters.

Methods:

A total of 100 American Society of Anesthesiologist Grade I and II adult female patients undergoing elective laparoscopic cholecystectomy under general anaesthesia were selected and randomly divided into two groups of 50 patients each. In Group I, CLMA™ and in Group II, ALM™ was placed prior to tracheal extubation. Haemodynamic parameters were recorded during ETT/LM exchange. Glottic view was seen through the LM using flexible fibrescope. Coughing/bucking during removal of LM, ease of placement and post-operative sore throat for both groups were graded and recorded.

Statistical Analysis:

Data within the groups was analysed using paired t-test while between the groups was analysed using unpaired t-test. Chi-square test was used to analyse grades of glottic view, coughing, and post-operative sore throat.

Results:

In Group I, there was a significant rise in systolic blood pressure and heart rate in contrast to insignificant rise in Group II. Glottis view was significantly better in Group II. Incidence of coughing, ease of placement and post-operative sore throat was identical between both groups.

Conclusion:

ALM™ is superior to CLMA™ for exchange of ETT before extubation due to greater haemodynamic stability during exchange phase and is better positioned.

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

We performed a prospective, open-label, randomised controlled trial comparing the air-Q(®) against the LMA-ProSeal™ in adults undergoing general anaesthesia. One hundred subjects (American Society of Anesthesiologists physical status 1-3) presenting for elective, outpatient surgery were randomly assigned to 52 air-Q(®) and 48 ProSeal devices. The primary study endpoint was airway seal pressure. Oropharyngolaryngeal morbidity was assessed secondarily. Mean (SD) airway seal pressures for the air-Q(®) and ProSeal were 30 (7) cmH (2) O and 30 (6) cmH(2) O, respectively (p = 0.47). Postoperative sore throat was more common with the air-Q(®) (46% vs 38%, p = 0.03) as was pain on swallowing (30% vs 5%, p = 0.01). In conclusion, the air-Q(®) performs well as a primary airway during the maintenance of general anaesthesia with an airway seal pressure similar to that of the ProSeal, but with a higher incidence of postoperative oropharyngolaryngeal complaints.

[Evaluation of the new supraglottic airway devices Ambu AuraOnce and Intersurgical i-gel. Positioning, sealing, patient comfort and airway morbidity]

BACKGROUND

Supraglottic airway devices (SGAD) have become more important in airway management over the past years and an objective comparison of the available devices is in order.

METHODS

In a prospective study the four SGADs LMA-Classic(cLMA), LMA-ProSeal (PLMA), Ambu AuraOnce and Intersurgical i-gel were compared in groups of 40 patients in ambulatory surgery, with respect to the feasibility of positioning, leak tightness, patient comfort and airway morbidity. The seal test of the airway devices was carried out with a specially constructed pneumotachograph.

RESULTS

Adequate placement on the first attempt was achieved in 92.5% with the cLMA, 85% with the PLMA, 92.5% with the AuraOnce and 82.5% with the i-gel (p>0.05). There were no clinically relevant differences in mean insertion times: cLMA 13.8 s (+/-3.4 s), PLMA 13 s (+/-3.2 s), AuraOnce 11.2 s (+/-2.7 s; p<0.05) and 13.9 s (+/-3.6 s) with the i-gel. A tight seal at a constant oropharyngeal pressure of 15 cmH(2)O was achieved in 85% of the cases (34 cases) with the cLMA, 90% (36 cases) with the PLMA, 97.5% (39 cases) with the AuraOnce and 72.5% (29 cases) with the i-gel (p<0.05). A tight seal at a constant oropharyngeal pressure of 20 cmH(2)O was seen in 62.5% with the cLMA, 60% with the PLMA, 67.5% with the AuraOnce and in 50% with the i-gel of the cases (p>0.05). Airway morbidity was not observed in any group. Significantly more patients complained of a sore throat after using the cLMA (p<0.05).

CONCLUSION

The tested SGADs were comparable with regard to ease of insertion, insertion times and airway morbidity. Considering leak tightness and patient comfort the PLMA and the AuraOnce fared better with regard to tightness of seal and patient comfort.