Usually videolaryngoscopy using a videolaryngoscope with a classic Macintosh design is performed with the blade in the vallecula and the epiglottis elevated from the vocal cords indirectly, as in direct laryngoscopy. However, during an audit of videolaryngoscopic practice we noticed that, in obtaining the best view, clinicians frequently and inadvertently advanced the blade into the vallecula to get a better view, such that the epiglottis was downfolded and elevated directly from the vocal cords. However, a better view does not necessarily lead to higher intubation success. In this randomized, controlled trial, we want to determine the efficacy of videolaryngoscope-guided tracheal intubation using an alternative position for the blade in patients with normal airways.
Anaesthesia will be induced in the conventional matter. For patients randomized to the intervention group, when the anaesthesiologist considers the depth of anaesthesia to be sufficient, a C-MAC® videolaryngoscope (Karl Storz, Tuttlingen, Germany), will be placed into the patients mouth. The best possible view of the vocal cords will be obtained with the blade positioned normally in the vallecula anterior to the epiglottis. The epiglottis will be elevated from the vocal cords indirectly, identical with direct laryngoscopy. After this, the best possible view of the vocal cords will be obtained with the blade positioned alternatively in the vallecula posterior to the epiglottis, such that the epiglottis is downfolded and elevated directly from the vocal cords. Views will be scored in both positions using the Cormack and Lehane classification system. When correct laryngoscope positioning can't be achieved with a size 3 blade, a size 4 blade will be used. For patients not randomized to the intervention group, anaesthesia will also be induced in the conventional matter. When the anaesthesiologist considers the depth of anaesthesia to be sufficient, a C-MAC® videolaryngoscope (Karl Storz, Tuttlingen, Germany), will be placed into the patients mouth. The best possible view of the vocal cords will be obtained with the blade positioned normally in the vallecula anterior to the epiglottis. The epiglottis will be elevated from the vocal cords indirectly, identical with direct laryngoscopy. The view will be scored in this position using the Cormack and Lehane classification system. After this, the patient will be intubated. Patients will be interviewed 2 and 24 hours postoperatively about sore throat, dysphonia, dysphagia and coughing.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Masking
NONE
Endotracheal intubation will be achieved using a C-MAC® videolaryngoscope (Karl Storz, Tuttlingen, Germany) with a size 3 Macintosh blade. The best possible view of the glottic inlet will be scored with the blade tip positioned in the vallecula. Next, the view of the glottic inlet will be scored with the blade advanced further into the vallecula, until the epiglottis flips infero-posteriorly and becomes downfolded into the trachea. The glottic view will be scored in both positions using the Cormack and Lehane classification system. After successful intubation, the blade will slowly be withdrawn into the vallecula to elevate the epiglottis back to its normal position.
Catharina Ziekenhuis Eindhoven
Eindhoven, Netherlands
The Cormack and Lehane grade
The Cormack and Lehane grade scored in both positions of the C-MAC® videolaryngoscope and consequent success of intubation
Time frame: Patients will be followed for the duration of induction of anaesthesia, an average of 10 minutes
Discomfort
Sore throat, dysphonia, dysphagia and coughing reported by patients 2 and 24 hours postoperatively
Time frame: Patients will be followed for 24 hours postoperatively
Use of adjuncts
Frequency of use of a stylet, gum elastic bougie or BURP manoeuvre.
Time frame: Patients will be followed for the duration of induction of anaesthesia, an average of 10 minutes
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.