Approx 1:300 patients presenting for non-obstetric surgery will have unexpectedly difficult tracheal intubation. Obstetric patients have a higher incidence - approx 1:80.
Situation A) Failed intubation, able to ventilate.
Give yourself 4 attempts to intubate. Continue to ventilate the patient and maintain anaesthesia.
Check neck flexion, head extension, adequate muscle relaxation.
Repeat laryngoscopy with external laryngeal manipulation.
Consider longer / alternative blade (straight blade / McCoy).
Consider gum-elastic bougie or introducer.
Consider LMA or ILMA - as conduit for an ML tube or small flexible tube.
Situation B) Failed intubation, unable to ventilate,
Immediate priority is to establish ventilation.
Attempt four-handed face-mask ventilation with oral+nasal airway, jaw thrust, and reduced cricoid pressure.
Call for help.
Have you waited long enough for the relaxant to be effective?
Consider the reasons why intubation has failed - the points outlined in Situation A can be addressed and a further brief attempt at intubation made. Subsequent steps should not be delayed.
Site an LMA
Consider laryngospasm and treat with increments of IV agent
If LMA ventilation ineffective leave it in situ and proceed to either 1) cannula cricothyroid puncture or 2) surgical crico-thyroidotomy
1)
Insert kink-resistant cannula through crico-thyroid membrane, aspirate air, and get assistant to hold it securely in position.
Attach high-pressure ventilation system, connected to mini-schroeder valve on anaesthetic machine, and ventilate
2)
Stab a blunt, short (Minitrach) scalpel through the crico-thyroid membrane and enlarge the incision with blunt dissection.
Apply caudal traction to the cricoid with a tracheal hook and insert a cuffed 6 or 7mm tracheostomy or ETT tube.
Inflate the cuff and ventilate
