Resp - Equipment Flashcards
Can you outline some indications for which you would consider bronchoscopy
Diagnostic uses include:
: The aspiration of sputum or cytology samples for microbiological or pathological
analysis
: Visualization of bronchial tree in airway trauma, for burns or if a lung lesion
(tumour or inhaled foreign body) is suspected
: Aspiration can be assisted by first instilling small volumes (typically 20 mL) of saline
during a bronchial wash (BW) or a more formal broncho-alveolar lavage (BAL)
Therapeutic uses:
: BW may also be used as a therapeutic manoeuvre for lobar collapse via the removal
of mucus plugs or secretions
Describe Broncho-alveolar lavage
BAL involves instilling 50–200 mL of saline into a target lung segment. As much saline as
possible is aspirated back through the bronchoscope and collected by placing a sample chamber between the bronchoscope suction port and the wall suction. Samples are often for
cytological or immunological analysis, although larger volumes of saline can be used to try and remove particulate matter and debris or in therapeutic lavages such as following smoke
inhalation with contamination of the bronchial tree.
What are the main risks associated with bronchoscopy?
The main risks include:
Hypoxia, difficulty with ventilation, V/Q mismatch, bronchospasm
Hyperinflation/air trapping/barotraum/pneumothorax
Miscellaneous – high intracranial pressure/bleeding/tachycardia/hypertension
How would you minimize these risks?
Pre-oxygenation
Adequate monitoring (oxygen saturation/capnography)
An appropriate-sized endotracheal tube
Appropriate sedation and/or muscle relaxant
Minimizing duration (allow time in between for recruitment)/limiting amount of saline
used for washouts
What are the indications for chest drain insertion?
Pneumothorax
: in any ventilated patient
: tension pneumothorax after initial needle relief
: persistent or recurrent pneumothorax after simple aspiration’
Malignant pleural effusion
Empyema and complicated parapneumonic pleural effusion
Traumatic haemopneumothorax
Post-operative – for example, thoracotomy, oesophagectomy, cardiac surgery
Where should a chest drain be sited?
Insertion should be in the ‘safe triangle’ delineated by the anterior border of the latissimus
dorsi, the lateral border of the pectoralis major muscle, a line superior to the horizontal
level of the nipple and with an apex below the axilla.
Discuss the pros and cons of the Seldinger vs. an open chest drain.
The Seldinger drain has less leakage, a smaller hole, it is adequate for less viscous fluids and
air but is more likely to kink. [1]
An open drain has better pleural access, a bigger hole and drains complex collections or
viscous fluids, such as pus or blood.
What are the ultrasound features that would suggest a pneumothorax?
Absence of lung sliding
Absence of B lines
Lung point
Stratosphere sign
What precautions would you take with the intercostal drain during transfer?
The drain should be properly secured.
The bottle should be kept upright at a lower level than insertion site and with an adequate
underwater seal.
You should ensure it is free of kinks.
There needs to be suction tubing open to the air.
Appropriate monitoring is required.
Consider a Heimlich (flutter) valve.
What information can we get from pulmonary function tests?
Lung volumes and capacities
Spirometry (FEV1, FVC values and peak flow)
DLCO (transfer factor)
How could DLCO help in this situation?
Diffusion capacity of the lung for carbon monoxide (DLCO), also known as the ‘transfer
factor’ (TLCO), is a measurement of the ease of transfer for CO molecules from alveolar gas
to the haemoglobin of the red blood cells in the pulmonary circulation. It often is helpful for
evaluating the presence of possible parenchymal lung disease when spirometry and/or lung
volume suggest a reduced vital capacity, RV, and/or total lung capacity. Interpretation can
be complicated if there is reduced alveolar ventilation (VA) such as lung resection,
restrictive lung defects, and so the DLCO:VA (KCO) ratio is often considered too.
A reduced DLCO and a reduced DL-to-VA ratio suggest a true interstitial disease such as
pulmonary fibrosis or pulmonary vascular disease.
What is FVC
Forced Vital Capacity: “the maximal volume of air exhaled with maximally forced effort from a maximal inspiration, i.e. vital capacity performed with a maximally forced expiratory effort”
What is FEV1
Forced Vital Capacity: “the maximal volume of air exhaled with maximally forced effort from a maximal inspiration, i.e. vital capacity performed with a maximally forced expiratory effort”
What is FRC?
functional residual capacity. It is the volume of gas present in the lung at end-expiration during tidal breathing. It is composed of ERV and RV, and is usually 30-35 ml/kg, or 2100-2400ml in a normal-sized person
What is RV
residual volume. It is defined as “the volume of gas remaining in the lung after maximal exhalation”,
What is ERV
(expiratory reserve volume) is the volume of gas that can be maximally exhaled from the end-expiratory level during tidal breathing
What is IC (inspiratory capacity)
is the maximum volume of gas that can be inspired from FRC.
What is vital capacity?
the volume change between the position of full inspiration and full expiration,
Why might DCLO be decreased?
-There is a genuine diffusion defect, eg. interstitial pulmonary fibrosis
-The patient is severely anaemic
-There is reduced lung expansion (i.e. a reduced TLC).
What are the current potential uses for an HFNC in intensive care?
De novo type 1 respiratory failure e.g. secondary to pneumonia (FLORALI study,)
Post-operative respiratory failure
During bronchoscopy
Pre (and per) oxygenation prior to (or during) intubation
Post-extubation respiratory distress
