AIRWAY OBSTRUCTION

See also the Difficult Airway Society's  Simple Composite Chart (106 KB)

Noisy, poor or absent ventilation
Increased inspiratory efforts/tracheal tug
Paradoxical chest/abdominal movements

EMERGENCY MANAGEMENT

Cease stimulation/surgery
100% oxygen (1)
Try chin lift/jaw thrust (2)
Request immediate assistance (3)
Consider allowing the patient to wake up, or
Ensure adequate depth of anaesthesia (4) and
Visualise and clear the pharynx/airway (5)
     If you suspect laryngospasm  see Laryngospasm
     If you suspect regurgitation see Regurgitation 
Insert oral and/or nasal airways
Reposition head, apply chin lift/jaw thrust (2)
Try "team" mask CPAP/IPPV (3)

Have someone feel the pulse and call out the SpO2 (1) (7)
If not already paralysed:
     Consider suxamethonium 1-2 mg/kg IV and atropine 0.012 mg/kg IV
      (see (8) (9) under Laryngospasm)
Make one attempt at intubation under direct vision
      See also the Difficult Airway Society's Failed ventilation (101 KB)

IF YOU CANNOT INTUBATE

Consider a laryngeal mask (8)
See also the Difficult Airway Society's Default strategy for intubation including failed direct laryngoscopy (112 KB)
                                                    and Failed rapid sequence induction (54 KB)
IF THIS FAILS

Do an immediate cricothyrotomy
Ventilate with 100% oxygen

Consider:

Misplaced/kinked/blocked ETT [see NOTE (2) in  CHECK Algorithm]
Bronchospasm
Pneumothorax
Consider possible obstruction distal to ETT:
Try pushing a small tube past it
     or push the obstruction down one bronchus
     and ventilate the other lung, with a clean tube

Review the patient to:
     confirm a clear airway
     exclude pulmonary aspiration
     exclude post obstructive pulmonary oedema
     explain what happened
If there is a risk of awareness:
     go and see the patient in the ward
     explain again and reassure them (9)
     advise them to warn future anaesthesiologists.
See  - After the Crisis

Top

The figures reported here are based on an analysis of 62 of the first 4000 AIMS anaesthesia incidents. It was judged that correct use of the algorithm would have led to earlier recognition of the problem and/or better management in 11% of the 62 incidents.

(1) Desaturation was documented in 65% of cases.
(2) This may relieve mild laryngospasm and some obstructions. See Note (4) on page xxx under Laryngospasm 
(3) Tasks for "team" include mask CPAP/IPPV and subsequent intubation or cricothyrotomy, if necessary.
     Ask for 4 people:
      Person I to hold mask and jaw with 2 hands and intubate.
      Person II to hold emergency oxygen and squeeze the bag
      Person III to ensure adequate anaesthesia and IV access
      Person IV to find and pass equipment and help others.
(4) This will often relieve laryngospasm and is a prerequisite for pharyngoscopy and suction. 14% of cases of laryngospasm presented as airway obstruction.
(5) This is vital at this stage; half of the incidents reported had blood, secretions, a foreign body, or intrusive mass. Obviously, an intrusive mass cannot be cleared; care should be taken not to cause bleeding. It is also important before mask CPAP or IPPV to prevent aspiration.
(6) Get an assistant to have a scalpel and tube ready for you, as this will save time once the decision to proceed with cricothyrotomy is made.
(7) There were 4 cardiac arrests, 3 dysrhythmias and 1 death.
(8) The LMA is easy to insert and works well in about 95% of cases. It does not necessarily provide airway protection.
     (see Caponas G. Intubating laryngeal mask airway. Anaesth Intensive Care 2002;30:551-569)
     (consider also Brimacombe J, Keller C. The ProSeal laryngeal mask airway.Anesthesiol Clin North America
      2002;20(4):871-891)
(9) Provide written advice and document this in the medical record.