Laryngeal mask airway supreme™ for difficult airway management and establishing ventilation in the intensive care unit

Sir,

An 80-year-old male, in-patient, known case of hypertension, insulin dependent diabetes mellitus, hemiplegia, chronic renal failure and bed ridden for 5 years, admitted with the complaints of fever and productive cough was shifted to the intensive care unit (ICU) following sudden decrease of consciousness and respiratory distress. Call was sent to the anaesthesiologist for emergency airway management. The patient had a Glasgow Coma Scale of six, with respiratory distress and upper airway obstruction. He had a totally fixed neck, fixed flexion and rotational deformity of the head and neck with the chin rotated to the left [Figure 1]. The patient's oxygen saturation on pulse oximetry (SpO₂) on oxygen through the face mask, 60-65%. The arterial blood gas showed paO₂ of 54 mmHg, pCO₂ of 114 mmHg and pH of 6.19. In view of the difficult intubation, call was sent for the flexible fibreoptic bronchoscope. With the bronchoscope about 15 min away, airway management were started. The patient was given fentanyl, 50 μg and propofol, 20 mg. Attempts at bag mask ventilation failed. Three attempts at laryngoscopy using Miller blades size three and four showed Cormack Lehane Grade IV view with an inability to intubate the trachea. The situation deteriorated into “cannot intubate, cannot ventilate”. Insertion of Classical Laryngeal Mask Airway^™ (LMA; The Laryngeal Mask Airway Company, San Diego, California, USA) sizes three and four was tried. The LMAs kept slipping out and manual ventilation was not possible due to upper airway obstruction. By now the spO₂ had dropped to 40-45% with heart rate of about 40 beats/min. With the bronchoscope still not available, we used the Laryngeal Mask Airway Supreme^™ (LMAS; The Laryngeal Mask Airway Company, San Diego, California, USA) size three. The fixed curvature facilitated introduction. It easily slid into place, was then fixed using its ‘Fixation Tab’. It remained stable in its place and allowed adequate ventilation. The patient was connected to the ventilator through the LMAS and ventilation initiated. In view of the patient's unstable vital parameters it was decided to continue respiratory support through the LMAS and defer bronchoscopic intubation temporarily.

Figure 1.

X-ray showing the distorted airway anatomy

After 1½ h of ventilatory support through the LMAS the spO₂ improved to 85-90%, with paO₂ of 83.2 mmHg, pcO₂ of 48 mmHg and pH of 7.14. The LMAS was then removed and the trachea successfully intubated orally by flexible fibreoptic intubation under local anaesthesia and sedation.

The American Society of Anesthesiologists Difficult Airway Algorithm stresses on the use of the LMA in difficult airway management.[1]

In view of the failure of the LMA and the deteriorating condition we used the LMAS as a rescue airway device. The LMAS is a sterile latex free single use supraglottic device, made of medical grade polyvinyl chloride. The second seal gastric inlet allows passive or active suctioning of the gastric tract and prevents insufflation during ventilation. The elliptical and anatomical shaped airway tube allows easy insertion.[2] The oval shape matches the shape of the mouth and reduces rotation in the pharynx. The strengthened cuff prevents infolding and the epiglottic fins prevent airway obstruction from down folding of the epiglottis.[3] These superior design characteristics of the LMAS allowed easy insertion and prevented rotation in an anatomically distorted airway, while the ‘Fixation Tab’ allowed secure stabilisation and fixing.

We were faced with dual difficulty of airway control and initiating ICU ventilation. We chose the LMA over the Proseal^™ as we believed that the preformed curve would facilitate insertion and the fixation tab would allow secure fixation, allowing us to achieve our dual aims of airway control and ventilatory device.