- where is the tube placed
Tube is placed into trachea via mouth (orotracheal) or via nose (nasotracheal)
Aim: to maintain patent airway
- perioperative management of anaesthetised patient
- emergency medicine: acute respiratory failure, poor oxygenation and ventilation, the risk of respiratory compromise
What else should be used (as a guide) in endotracheal intubation?
Laryngoscope - to visualise pharynx
What is indicative of the correct placement of the endotracheal tube? (2)
- bi-lateral breath sounds on auscultation
- exhaled CO2 measurement
Possible complications of endotracheal tube insertion (4)
- dental damage
- tracheal stenosis
- oesophageal misplacement of the tube
What is the preferred mode for long-term intubation?
What does tracheostomy involve?
Creation of reversible or permanent stoma below a cricoid cartilage
When do we use the procedure of cricothyrotomy?
Cricothyrotomy is usually used as a last resort - in emergency situations such as acute obstruction of the airway by blood, oedema or foreign body
*also used if intubation/ventilation with the supraglottic device has failed
Where the incision is made in cricothyrotomy?
In cricothyroid membrane
What is done once the access to the airway (intubation) has been gained? What's the next step? Why?
Aim: to assist and replace spontaneous breathing
What are the complications of mechanical ventilation?
- barotrauma (e.g. pneumothorax)
- ventilator-induced lung injury -> clinically looks like Adult Respiratory Distress Syndrome
What GCS would be indicative for endotracheal ventilation?
GCS of =/< 8
*as in that case protective reflexes such as cough and gag will be reduced -> so can insert endotracheal tube
What do we need to do before extubation and why?
- We need to suction airways
Aim: to minimise the risk of aspiration (fluids, foreign materials)
Criteria for extubation (what would be indicative to extubate a patient?) - 3 criteria
- sufficient spontaneous breathing
- presence of protective reflexes (coughing, swallowing)
- adequate level of consciousness (eye-opening, obeying requests)
Where the incision is made in tracheostomy?
Horizontal incision between cricoid cartilage and sternal notch -> insertion of suture and fixation of tracheostomy tube
What must be done and why post- tracheostomy insertion?
Chest X-ray -> to exclude pneumothorax and tube displacement
Definition of mechanical ventilation
Mechanical ventilation - use of respirator to assist or completely replace spontaneous breathing
What agents do we use to suspend spontaneous breathing (for purpose)? (3)
- muscle relaxants
- hypnotic agents
Aim: to permit intubation, suppress respiratory centres, reduce muscular resistance for mechanical ventilation
What is capnometry/capnography?
Allows assessment of CO2 concentration in exhaled air -> to determine if ventilation is adequate
The process of easing a patient off mechanical ventilatory support
Side effects of mechanical ventilation?
If PEEP (positive end-expiratory pressure) is set too high: inflation of the lung with decreased compliance
- Barotrauma → rupture of alveoli → pulmonary emphysema, pneumomediastinum, pneumoperitoneum, pneumothorax, and/or tension pneumothorax.
- ↓ Cardiac output (as venous return is obstructed by increase in intra-thoracic pressure)
- ↓ Liver perfusion
Mechanism of action of a ventilator
Mechanism of action
- PEEP (positive end-expiratory pressure)↑ alveolar pressure and alveolar volume → collapsed or unstable alveoli reopen → improves ventilation/perfusion relation
- Provides an adequate arterial PaO2 at a low and safe concentration of oxygen (< 60%) → reduces the risk of oxygen toxicity
- what is this/what happens?
- what does it lead to?
Bronchoconstriction during anaesthesia -> leads to severe hypoxia and hypotension if left untreated
Risk factors for bronchospasm (3)
- reactive airway disease (asthma, COPD)
- viral upper respiratory tract infection
Clinical features of bronchospasm
Treatment of bronchospasm
- basic management
- pharmacological (1st and 2nd line)
A. Basic measures
- Discontinuation manipulating measures/surgery
- Manual ventilation with a FiO2 of 100%
- Deepen anesthesia
- Exclude differential diagnosis (e.g. pneumothorax, laryngospasm)
B. Pharmacotherapy in severe bronchospasm
- First-line: salbutamol