3.2 Extubation Flashcards
a) What airway, respiratory and cardiovascular problems may follow the removal of a tracheal tube? (50%)
Airway:
» Sore throat, hoarseness.
> > Foreign body causing obstruction:
teeth, throat pack, blood clot.
> > External compression of airway due to surgical site swelling/bleeding.
> > Laryngospasm: triggered by blood, secretions and airway manipulation during light anaesthesia.
> > Laryngeal oedema.
> > Laryngeal trauma caused during intubation (e.g. bougie use), causing bleeding, swelling, tears.
> > Vocal cord paralysis: direct trauma/pressure.
> > Vocal cord dysfunction.
> > Tracheomalacia: erosion/softening of tracheal rings due to prolonged intubation, retrosternal thyroid, large thymus or tumour.
> > Tracheal stenosis after prolonged intubation.
Respiratory problems may follow the removal of a tracheal tube?
Respiratory:
» Coughing.
> > Mucociliary dysfunction.
> > Diffusion hypoxia.
> > Basal atelectasis causing
ventilation/perfusion mismatch.
> > Inadequate minute ventilation
due to ongoing sedation.
> > Post-obstructive pulmonary oedema.
> > Bronchospasm.
> > Pulmonary aspiration.
> > Respiratory failure due to any respiratory or airway complications.
Cardiovascular problems may follow the removal of a tracheal tube?
Cardiovascular:
> > Catecholamine release causing
tachycardia and hypertension.
> > This may result in reduced
ejection fraction in patients with coronary
artery disease.
> > Risk of silent or overt myocardial
infarction due to increased myocardial
oxygen demand (effect exacerbated if there is hypoxaemia due to other complications of extubation).
b) List the patient factors that may contribute to a high-risk extubation. (30%)
Patient factors:
» Airway: dysmorphia, musculoskeletal disease contributing to airway
difficulties (rheumatoid arthritis, ankylosis), airway pathology (tumour),
obesity. These issues may have been detected at preoperative
assessment or at intubation: difficult airway assessment, difficult face
mask ventilation, difficult intubation, complications at intubation.
> > Breathing: respiratory disease including asthma, obstructive sleep apnoea, chronic obstructive pulmonary disease, recent upper respiratory tract infection (especially in children), smoking.
> > Cardiovascular:
ischaemic heart disease, unstable arrhythmias.
> > Neurological:
posterior fossa tumour, head injury, Guillain–Barré,
myasthenia gravis, multiple sclerosis.
> > Gastrointestinal:
full stomach, reflux, hiatus hernia.
> > Muscular:
muscular dystrophy, dystrophia myotonica.
Surgical
Change in airway - haematoma
swelling
Trachy
Wired shut mouth
Bleeding post op
surgical factors that may contribute to a high-risk extubation. (30%)
Surgical factors:
> > Site:
airway, head, neck, thorax,
posterior fossa, cervical spine.
Any surgery requiring use of double-lumen tube.
> > Complications of surgery or double-lumen tube use: bleeding, swelling, infection.
> > Duration:
prolonged intubation predictive
of problems with extubation.
> > Position:
Trendelenberg exacerbates development of laryngeal oedema.
> > Intraoperative issues not directly related to airway: difficulty achieving adequate ventilation, hypothermia, significant blood loss, electrolyte
imbalance, fluid shifts.
c) Outline the strategies used to prevent airway complications if a difficult extubation is anticipated in the operating theatre. (20%)
There are three options here: extubate now but take steps to make it safer,
extubate later or don’t extubate at all.
The decision depends on the likely issues anticipated.
Extubate in theatre:
> > Pre-medicate with
proton pump inhibitor if appropriate.
> > Plan A, plan B, plan C.
> > Involve colleagues with specific airway skills
+/− ENT.
> > Ensure full difficult airway kit to hand.
> > Ensure cardiovascular, respiratory and metabolic stability.
> > Optimise oxygenation prior to starting,
ongoing full monitoring.
> > Ensure full reversal of neuromuscular blockade.
> > Position: left lateral head down or sitting up.
> > Extubation wide awake: good grip, tongue protrusion, adequate minute ventilation.
Consideration of additional techniques:
Consideration of additional techniques:
» Exchange of tube for SAD when deep
+/− still paralysed.
> > Use of airway exchange catheter.
> > Use of nasopharyngeal or oropharyngeal airway.
> > Flexible bronchoscope through the LMA to visualise the larynx and vocal cords to check for cord paralysis and tracheomalacia (if indicated due to
type of surgery).
> > Extubation onto noninvasive ventilation
or high-flow humidified oxygen.
> > Use of remifentanil to manage awake extubation.
Delayed extubation if reversible contributing factors:
Delayed extubation if reversible contributing factors:
> > Transfer to ICU with a plan for delayed extubation.
> > Avoid positive fluid balance.
> > Ensure normothermia.
> > Normalise electrolytes.
> > Allow any airway swelling to settle;
consider need for steroid therapy.
Surgical tracheostomy if contributing factors are not readily reversible:
> > Nature of surgery: flaps, spinal fixation, complications from airway tumour.
