Comparison of the Glidescope and Macintosh Laryngoscope for Double Lumen Endotracheal Tube Intubation

Comparison of the Glidescope and Macintosh Laryngoscope for Double Lumen Endotracheal Tube Intubation

Patients undergoing chest surgery often require insertion of a breathing tube (double lumen tube) after they are unconscious. The double lumen tube enables the anaesthetist to ventilate (assist breathing) one lung at a time. The other lung is partially deflated to enable enough space for the surgeon to perform the procedure. The breathing tube is inserted with a laryngoscope (blade with a light at the end) so the vocal cords can be seen. This is standard medical practise. Two laryngoscopes are commonly used at Toronto General Hospital to insert the tube. The Macintosh laryngoscope has been is use for over 50 years and the Glidescope for over 10 years. Both devices have been extensively researched for single lumen tubes insertion and found to be very safe and effective. Research is limited to say which of the two laryngoscope is the most effective for double lumen tubes.

The Glidescope (GVL) has been extensively studied for single lumen tube intubation and found to be a very safe and useful device. It is a particularly useful for patients with difficult airways as it has a camera attached to the blade. Despite being used for double lumen tube (DLT) intubations, research of its effectiveness and safety, is lacking. The study aims to determine the speed and safety of the GVL for DLT insertion. This information will assist anaesthetists in choosing the appropriate laryngoscope for DLT intubation of their patients.

Inclusion Criteria:

Population: planned elective lung surgery requiring general anaesthesia with a double lumen endotracheal intubation, signed informed patient consent.

Exclusion Criteria:

• Previous failed intubation,
• history of difficult intubation or anticipated difficult intubation (2 risk factors of mallampati score 3 or greater,
• incisor gap < 3.5cm, thyromental distance < 6.5cm,
• reduced neck extension and flexion),
• alternative method of intubation indicated eg rapid sequence intubation,
• fibreoptic intubation,
• contra-indication to a left double lumen tube eg endobronchial tumor,
• significant deviation or compression of the trachea and bronchi.,
• contraindication to one lung ventilation eg severe hypoxia or pulmonary hypertension,
• anticipated difficult bag mask ventilation,
• symptomatic gastro-oesophageal reflux,
• oral/pharyngeal/laryngeal carcinoma,
• loose teeth,
• allergy to rocuronium, BMI > 40.