Comparative evaluation of gum-elastic bougie and introducer tool as aids in positioning of ProSeal laryngeal mask airway in patients with simulated restricted neck mobility

Usefulness of bougie-preloaded proseal laryngeal mask airway versus digital insertion technique in correct placement of the device

Background and Aims

Digital technique of proseal laryngeal mask airway (PLMA) insertion carries high chance of failed first attempt successful placement. We aimed to compare the number of attempts taken for correct placement of bougie-preloaded PLMA versus traditional digital insertion technique. Ease of insertion, time taken, hemodynamic responses during insertion, and evidence of trauma were also assessed.

Material and Methods

This prospective, randomized, open-label study was performed in 60 patients. All patients were administered general anesthesia according to a standardized protocol.After induction of general anesthesia in group P, proseal insertion was performed following the traditional digital technique. In group B, bougie-preloaded PLMA was used. A soft gum elastic bougie was passed through the gastric channel of PLMA, with 15cm protruding distally through the gastric port. Attempts at successful insertion and ease of insertion were noted.

Results

Time taken for successful insertion was significantly shorter in group B compared to group P (15.3 ± 4.5 vs. 57 ± 12.02 s, respectively). The first attempt success in group B was 90% versus 60% in group P. The number of moderate to hard insertion was significantly lesser in group B (10 vs. 40, respectively). Blood stain on device was seen in 3.3% in group B compared to 30% in group P. MAP at insertion and at 1, 3, and 5 min was significantly higher in group P. Heart rates were comparable.

Conclusion

Bougie-preloaded proseal insertion has significantly higher first attempt insertion success rates and is significantly faster and less traumatic with blunted blood pressure response compared to traditional digital insertion technique.

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.

A novel technique for insertion of ProSeal™ laryngeal mask airway: Comparison of the stylet tool with the introducer tool in a prospective, randomised study

BACKGROUND AND AIMS

The ProSeal™ laryngeal mask airway (PLMA) has a soft cuff which tends to fold on itself during insertion, resulting in reduced first-attempt success rate. We compared the standard introducer technique of PLMA insertion with a novel method to prevent folding of the cuff using a Rüsch™ Stylet.

METHODS

This randomised superiority trial included 120 American Society of Anesthesiologists I-II patients between 18 and 80 years, undergoing elective surgeries under general anaesthesia using a PLMA for airway management. The PLMA was inserted using the standard introducer tool in sixty patients (Group IT), while in sixty other patients, a Rüsch™ Stylet was inserted through the drain tube up to its tip. (Group ST). The primary outcome was first-attempt success rate. Secondary outcomes included overall insertion success, number of attempts, total time to successful insertion, presence of air leaks, haemodynamic response to insertion and quality of fit assessed using Brimacombe's fibre-optic scoring. Continuous variables were compared using independent t-test or Mann-Whitney U-test and categorical variables were analysed using Chi-square test or Fisher's exact test.

RESULTS

First-attempt success rate of insertion was higher in Group ST compared to Group IT (95% vs. 82%, P = 0.04). Favourable grade of placement was better in Group ST (86.7% vs. 52.5%, P < 0.001). Overall insertion success rates and haemodynamic responses were comparable between the groups.

CONCLUSIONS

PLMA insertion using the stylet tool has a higher first-attempt insertion success and superior placement compared to insertion using the conventional introducer tool.