A 72 year old woman (55kg), Mrs X, with a history of severe emphysema and chronic bronchitis is intubated in the Emergency Department (ED) because of drowsiness associated with hypercarbia after her initial arterial blood gas analysis revealed:
You are called to the ED to assess and admit this woman to ICU. The history from her daughter reveals that Mrs X lives independently but is limited by severe breathlessness with exercise.
At one week she remains ventilator dependent.
(d) What may interfere with her weaning and what may be done to facilitate weaning?
A list may be best here:
- breathing system; demand valve resistance, humidifier, turbulence
- ETT; too small
- Airway; untreated asthma, secretions
- Lung interstitium; oedema, collapse, infection
- Musculoskeletal; weakness, hyperinflation, kyphoscoliosis
- Cardiovascular; low cardiac output state, ischaemia
- CNS drive; dugs, stroke,
The aim is to minimise the external work of breathing against inefficient ventilators and tubing, consider a tracheostomy which allows staged separation from the ventilator and improve all aspects of the patients general condition including nutrition, K/PO4/Mg, lung function and cardiovascular status.
A systematic approach is in order.
In generic terms, this table lists the usual suspects:
Respiratory load |
Increased work of breathing
|
Cardiac load |
|
Neurological causes |
|
Musculoskeletal causes |
|
Metabolic disturbances |
|
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