Dr James DuCanto:
Middle aged male presents for urgent surgery with multiple medical coomorbities (on renal transplant list), and multiple indicators of difficult direct laryngoscopy:
1. Obesity/sleep apnea/fat neck
2. Mallampatti 4
3. Thyromental distance 6 cm
4. Neck Range of motion limited to less than 90 degrees.
Plan (A) was thorough BiPAP pre oxygenation followed by DL/VL with moderate to deep sedation (no Succinylcholine of Non-depolarizing muscle relaxants, as mask ventilation predicted to be difficult to impossible based on above data and my clinical intuition). Plan (B) was an SGA based technique, based on the needs for sedation and topical local anesthetic application.
Difficult pre-O2 period, as light sedation and poor mask fit with tight fitting mask straps proved a bit problematic until I manually improved the mask fit and performed a light jaw thrust to allow the Oxylator to reach its pressure release setting of 20 cm H2O. This despite light sedation (fentanyl 20 mcg, hydromorphone 0.2 mg, midazolam 1 mg).
Upon reaching the target pre oxygenation level per gas analyzer (End-tidal O2 88%), deep sedation induced with rapid injection proposal 50 mg in lidocaine in lidocaine 70 mg.
Direct laryngoscopy grade 2A, Video laryngoscopy grade 1 with the McGrath Mac 3. Brief pause of tracheal tube at laryngeal opening to allow for the relaxation of vocal cords to permit tracheal tube passage off of a GlideRite stylet. Small amount of yellow secretions seen during laryngoscopy, but they did not soil airway or impair optics of the McGrath VL scope.
1. The use of a combined DL/VL device permitted me to “grade” the DL experience for current and future airway endoscopists, and permitted me the flexibility and safety of an advanced airway tool in the event that the airway was unmanageable by DL.
2. The McGrath Mac laryngoscope is lightweight and allows gentle endoscopy which permits its use during sedated laryngoscopy procedures. Following the base of tongue with the device into the proper position before force is briefly applied to document the DL grade allowed this procedure under deep sedation.
3. BiPAP preoxygenation contributed to the safety of this procedure. Passive pre-oxygenation procedures (which are standard operating procedure in the current day and age) require substantial revision when dealing with airways in which difficulty with tracheal intubation are predicted.
James DuCanto, M.D.
Department of Anesthesiology
Director of Anesthesia Clerkship
Aurora St. Luke’s Medical Center
Milwaukee, Wisconsin USA