Advanced treatment techniques Flashcards
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Inspiratory reserve volume
The amount of air that can be taken into the lungs (above the tidal volume) upon forced inspiration.
Maximum voluntary expiration
Volume of air exhaled in 12 seconds during rapid forced breathing.
Residual volume
Volume of air remaining in the lungs after maximum forceful expiration.
Expiratory reserve volume
The amount of extra air above normal that you exhale during a forceful breath out.
Functional residual capacity
The volume remaining in the lungs after a normal, passive exhalation
Vital capacity
The maximum amount of air a person can expel from the lungs after a maximum inhalation.
Inspiratory capacity
Measures how much air you can breathe into your lungs after you breathe out normally
Total lung capacity
The volume of air in the lungs upon the maximum effort of inspiration. Among healthy adults, the average lung capacity is about 6 liters.
Tidal volume
The amount of air measured in milliliters that moves in or out of the lungs during every respiratory cycle. It is normally 500 mL for a healthy adult male and 400 mL for a healthy adult female.
Closing volume
AS FRC decreases towards RV, dependent airways begin to close.
What happens if closing volume encroaches on Functional reserve capacity
Airway closure may occur during normal expiration causing atelectasis and a reduction in V/Q ratio.
What are the internal factors affecting lung volumes
Restrictive lung diseases
Consolidation
Atelectasis
Pulmonary oedema
External factors affecting lung volumes
Chest wall deformity
Lung compression from abdomen
Pleural effusion
Pneumothorax
Obesity
Neuromuscular Disease
Reduced inspiratory drive
Pain
Anxiety
General Anaesthetic
Sputum retention
When a patient is unable to clear their own secretions from their respiratory tract.
Can the patient achieve an adequate cough to clear secretions.
Phases of an effective cough
1) Deep inspiration, which generaets the volume requires for an effective cough.
2) Close of the larynx combined with contraction of the chest wall, diaphragm, and abdominal wall result in a rapid rise in intrathoracic pressure.
3) The glottis opens, resulting in high expiratory airflow and the coughing sound. Large airway compression occurs.
4) The high flows dislodge mucus from the airways and allow removal from the tracheobronchial tree.
Ineffective cough due to…
Pain (preventing deep breathing or expulsion); muscle weakness (inspiratory and expiratory muscles; inability to close the glottis); altered skeletal structure.
Work of breathing -
What is it and what is WOB determined by?
Energy required for the respiratory muscles to breathe.
Determined by:
Demand (drive to breathe)
Load (applied to the respiratory muscles)
Capacity (efficiency of the respiratory muscles).
Lung compliance
Expandability of the lungs and the chest wall.
Changes in volume in the lungs for a given change in pressure.
Allows the lungs to achieve appropriate functional reserve capacity.
Decreased lung compliance.
Restricted lung expansion -> reducedlung volume -> reduced FRC and increased tendency to collapse.
Increased lung compliance
Easy to inflate -> reduced ability to change lung volume -> harder to exhale due to less elastic recoil -> air trapping.
Intermittent Positive Pressure Breathing - IPPB (‘Bird’)
A form of assisted inspiration
Powered by pressured oxygen or air
Triggered by the patient at start of
inhalation
Preset pressure
Passive expiration
Indications for use of the ‘Bird’
Increased Work of Breathing
Sputum retention
Atelectasis
Reduced tidal volumes
Set up for the ‘Bird’ - Starting effort (or trigger) (1)
Effort required to trigger a breath
Minimal effort for increased WOB
Set up of the ‘Bird’ - Flowrate (2)
Rate of flow or ‘length of breath’
Low flowrate or ‘longer breath’
High flowrate or ‘shorter breath’
Aim for slow rate to allow for collateral ventilation
Starting point: half way (12 o’clock position)
