Comparative evaluation of BlockBuster andFastrach Laryngeal Mask Airway forendotracheal intubation

Thepresent study entitled “Comparative evaluation of BlockBuster and FastrachLaryngeal Mask Airway for endotracheal intubation.â€, was a prospective,randomised and controlled study done to evaluate and compare the performance ofBlockbuster and LMA Fastrach for tracheal intubation in 100 adult patients ofASA physical status 1/2 of either sex, in the age group of 18-60 years undergoingelective surgeries under general anaesthesia. After approval of protocol byHospital Ethics Committee, Clinical Trial Registry-India (CTRI/2018/02/011947);and written informed consent, patients were randomly allocated into followinggroups of 50 each:

Group1 (Blockbuster) (n=50) in which Blockbuster was used

Group2 (FT-LMA) (n=50) in which LMA Fastrach was used

Astandard monitoring and anaesthetic technique was used for all the patients. Allpatients were pre-medicated with inj. Glycopyrrolate 0.2 mg, inj. Midazolam0.04 mg/kg intravenously, 5 min before induction. After pre-oxygenation forthree minutes, anaesthesia was induced using morphine 0.1 mg/kg, propofol 2.0to 2.5 mg/kg. After checking for ability to achieve adequate mask ventilation,vecuronium 0.1 mg/kg was used to facilitate muscle relaxation. After openingthe sealed envelope, the allocated Blockbuster or FT-LMA was inserted. The cuffwas inflated with intracuff pressure of 60 cm H2O; optimalpositioning and ventilation were observed without an audible leak. Theoropharyngeal leak pressure and fibreoptic view of the larynx were determined. Awell lubricated cuffed ETT of appropriate size was inserted blindly toaccomplish intubation. If resistance was felt during blind attempt, the FOBguided intubation was performed. At confirmation of correct placement of thetracheal tube, SAD was removed using stabilizing rod to keep tracheal tube inplace.

TheSAD insertion parameters including number of attempts, ease of insertion; timetaken for Blockbuster or FT-LMA insertion; OLP; fibreoptic grading of laryngealview; number of attempt and time taken for tracheal intubation; time taken forSAD removal and blood stained on SAD were noted. Hemodynamic parameters wereobtained at the following time points: baseline; after induction ofanaesthesia; after device insertion, after 1 min, 2 min, 3 min, 4 min, 5 minand 10 min of tracheal intubation after SAD removal. Postoperative sore throat,hoarseness of voice, dysphagia in the first post-operative hour was recorded.The observations were analysed using Statistical Package for Social Sciences (SPSSInc., Chicago, IL, version 22.0 for Windows) and the following conclusions weredrawn:

1.      Both the groups were comparable in relation tothe demographic profile of the patients (age, gender, ASA grade, weight,height, Body mass index).

2.      The number of attempts, time taken and ease of insertion ofBlockbuster and FT-LMA was similar in both the groups.

3.      Mean OLP 28.30±1.89 cm H2O versus 24.46±1.75 cm H2Oin Blockbuster and FT-LMA group respectively.

4.      Fibreoptic view of the vocal cords (grades 4: only vocal cordseen and 3: vocal cord score plus posterior epiglottis visible) was comparablein both the groups.

5.      The success of first attempt blind endotracheal intubationwas significantly higher in the Blockbuster (100%) group than the FT-LMA (94%)group.

6.      No patients in Blockbuster group while 3 (6%) patients in FT-LMAgroup required second attempt using FOB.

7.      Time taken for endotracheal intubation was lesser withBlockbuster group (14.14±2.49 sec) as compared with FT-LMA group (18.34±2.86sec)

8.      The hemodynamic parameters (HR, SBP, DBP and MAP) atdifferent point of time were comparable in both the groups. Hemodynamicparameters increased after one min of intubation in both the groups with lesserincrease in group 1(statistically significant)

9.      The presence of macroscopic blood stain was comparable in bothgroups.

10.    The incidence and degreeof sore throat was comparable in both the groups.