SOB Flashcards
What is an ETT
exercise tolerance test
what does thalium show
metabolically active areas taking up more of it, perfusion defects, infarction (fixed defect), ischaemia (reversible defect)
what is the first treatement for a NSTEMI
thrombolysis
why is PO2 normal in anaemia
oxygen still in blood just not enough haemoglobin to carry it
what is haemodynamic instability
perfusion failure represented by clinical features of circulatory shock and advanced heart failure
what does a narrow QRS mean
SVT
what does a wide QRS mean
ventricular tachycardia
what are the factors contributing to production of shortness of breath
increased;
- work of breathing
- ventilatory drive
impaired resp muscle function
what can cause increased work on breathing
airflow obstruction (asthma, chronic bronchitis, tracheal obstruction)
decrease pulmonary compliance (pulmonary oedema, fibrosis)
restricted chest expansion (resp muscle paralysis)
what can cause increased resp drive
physiological dead space (ventilation-perfusion miss match e.g. infection, PE)
stimulation of resp centre
what are the chemical and neural stimulation of respiration
increased:
- aterial hydrogen ion conc (metabolic acidosis)
- arterial PacO2 (resp acidosis)
- central arousal (anxiety, thyrotoxicosis)
decreased:
-aterial PaO2 via aortic, carotid and brain stem chemoreceptors (pneumonia, anaemia)
pulmonary j receptor (in lungs) discharge (pulmonary oedema)
what is after load
force against which left ventricle contracts to eject blood into systemic circulation
what can increase afterload
increased peripheral resistance- which can be raised by high blood pressure
what happens when the left side of the heart fails
the left atrial and left ventricular pressures rise. The increased left-sided
pressures (called preload) produce back pressure on the lungs and cause a rise
in pulmonary capillary hydrostatic pressure resulting in accumulation of fluid
in the interstitial and intraalveolar lung spaces: - a condition known as
pulmonary oedema
how is pulmonary oedema manifested clinically
varying degrees of shortness of breath
what causes orthopnoea
increased venous return caused by lying down
what are the cardiac causes of SOB
- MI (most common)
- hypertension (leads to heart failure)
- arrhythmia
- valvular disease
- cardiomyopathies: dilated, hypertrophic, restrictive
- diabetes
what are the main diagnostic investigations in heart failure
ECG (hypertrophy, MI), CXR, echo
what investigations should be carried out for chest pain and in what order
ECG, bloods, CXR, ETT, (Thallium)
list non cardiac causes of SOB
- COPD
- Pneumothorax
- asthma
- musculoskeletal
what investigations should be carried out for breathlessness and in what order
ECG, CXR, bloods, Echo
what investigations should be carried out for palpitations and in what order
ECG, 24 hour ECG, Echo
what investigations should be carried out for murmurs and in what order
ECG, Echo
what investigations should be carried out for IE and in what order
blood cultures, (serology if negative) echo
what is the method of thallium perfusion scintigraphy
- Radiolabelled isotope taken up by normally perfused
myocardial cells. - Gamma camera counts radioactivity over the myocardium
- Images taken at rest and after stress
- Stress can be exercise or pharmacological
what is a cardiac CT angiogram
special type of x-ray examination of the
heart that helps determine if fatty or Calcium deposits
have narrowed the patient’ coronary arteries.
what are the pros and cons of CT angiography
p- • Excellent cardiac anatomy depiction • Non-invasive coronary arteries assessment • Functional assessment • Chamber assessment • Looks at vessels and lungs
c- • Significant radiation • Resolution less than angiograms • Contrast allergy/nephropathy • Need special equipment/expertise
what can be seen with echocardiography
- chambers
- valves
- muscle walls
- great vessels
- blood flow
- function of heart
What X-Ray technique is used to visualise the coronary arteries and how is it carried out?
Coronary angiography
Catheter in radial/femoral arteries, inject dye and then x ray
