Respiratory assessment Flashcards
What binds better to haemoglobin, O2 or CO and why is this relevant to assessment?
Carbon monoxide binds to haemoglobin about 200x more readily, the saturation probe cannot differentiate between blood saturated with oxygen or carbon monoxide
What percentage of best predicted PEF indicates life threatening bronchoconstriction?
<33%
What percentage of best predicted PEF indicates acute severe asthma?
<50%
How does hyperventilation present on capnography and capnometry?
Crisp wave form and low ETCO2
How does bronchospasm present on capnography and capnometry?
Due to trapped air in the alveoli being released inconsistently the capnography will follow a ‘shark fin’ curved shape and higher ETCO2
When auscultating a chest what can stridor signify?
Upper airway obstruction
When auscultating a chest what can wheeze signify?
Bronchoconstriction
-Asthma
-COPD
-Anaphylaxis
When auscultating a chest what can course crackles signify?
Excessive fluid in the lungs
-Aspiration
-Pulmonary oedema
-Chronic bronchitis
-Pneumonia
When auscultating a chest what can fine crackles signify?
Pulmonary fibrosis
When auscultating a chest what can increased vocal resonance signify?
Consolidation
Lobar collapse
Tumor
When auscultating a chest what can decreased vocal resonance signify?
Pleural effusion
What is the V/Q ratio?
The ratio between ventilation and perfusion, ideally = 1.
The ventilation rate (V) refers to the volume of gas inhaled and exhaled from the lungs in a given time period, usually a minute.
The perfusion (Q) of the lungs refers to the total volume of blood reaching the pulmonary capillaries in a given time period.
What is the average overall lung V/Q ratio?
0.8
What is the body’s response to a reduced V/Q ratio and how does this affect the CO2 levels?
Hypoxic vasoconstriction causes diversion of blood to better ventilated parts of the lung. However, in most physiological states the haemoglobin in these well ventilated alveolar capillaries will already be saturated. This means that red blood cells will be unable to bind additional oxygen to increase the pO2. As a result, pO2 level of the blood remains low, which acts as a stimulus to cause hyperventilation and bronchoconstriction, resulting in either normal or low CO2 levels
How can a PE cause haemoptesis?
Reduced blood flow from the right ventricle can cause an increase in pulmonary capillary wedge pressure causing capillary rupture
What is epiglottitis?
Inflammation and swelling of the epiglottis.
What is COPD?
Chronic Obstructive Pulmonary Disease is a group of lung conditions that cause breathing difficulties including:
Emphysema - damage to the air sacks in the lungs
Chronic bronchitis - long term inflammation of the airways
What are the most common airway obstructions in paeds and adults?
Paeds: Round foods
Adults: Meat
What is stridor?
Narrowing of the airway lumen causing the turbulence flow if air. Late sign means AW diameter is <50%
What is a FBAO?
Foreign Body Airway Obstruction
What are the general differences in uses between Macintosh and Miller laryngoscope blades?
Macintosh - Curved, provide better intubation conditions
Miller - Straight, usually used for intubating neonates and infants, literature suggests gives a better laryngoscopic view
What is the definition of hypoxia?
Low levels of oxygen in the body’s tissues and cells
What is apnoea?
Slowed or stopped breathing
What are normal sats levels for patients with COPD?
88-92%
What is the definition of hypoxaemia?
Low oxygen levels in the blood. (Sp02<92%)
What is the definition of hypercapnia?
Too much CO2 in the blood. (>45mmHg)
What is the difference between stridor and wheeze?
Wheezing is an obstruction of the lower airway heard more on expiration
Stridor is a higher pitch noise heard more on inspiration
What can you use to evaluate the risk of a PE?
Well’s score including risk of prev. DVT
