Acute LVF and Pulmonary Odema Flashcards
What is acute left ventricular failure and how does it cause pulmonary oedema?
When the left ventricle is unable to adequately move blood through the left side of the heart and out onto the body.
This causes a backlog of blood to be stuck at the left atrium, pulmonary veins and lungs.
As the vessels in these areas are engorged with blood due to the increased volume and pressure they leak fluid and are unable to reabsorb fluid from the surrounding tissues.
This causes pulmonary oedema
What is pulmonary oedema?
Pulmonary oedema is a condition caused by excess fluid in the lungs.
What can trigger acute left ventricular failure?
Iatrogenic (e.g. aggressive IV fluids in frail elderly patient with impaired left ventricular function)
Sepsis
Myocardial Infarction
Arrhythmias
How does acute LVF present?
Rapid onset breathlessness - made worse when lying flat and improves on sitting up.
What type of respiratory failure does acute LVF cause?
Type 1
Symptoms of LVF
Shortness of breath
Looking and feeling unwell
Cough (frothy white/pink sputum)
On examination, LVF can present as
Increase respiratory rate
Reduced oxygen saturations
Tachycardia
3rd Heart Sound
Bilateral basal crackles (sounding “wet”) on auscultation
Hypotension in severe cases (cardiogenic shock)
There may also be signs and symptoms related to underlying cause, for example:
Chest pain in ACS
Fever in sepsis
Palpitations in arrhythmias
What can be found in patients with acute LVF and right sided heart failure?
Raised Jugular Venous Pressure (JVP) (a backlog on the right side of the heart leading to an engorged jugular vein in the neck)
Peripheral oedema (ankles, legs, sacrum)
History
Clinical Examination
ECG (to look for ischaemia and arrhythmias)
Arterial Blood Gas (ABG)
Chest Xray
Bloods (routine bloods for infection, kidney function, BNP and consider troponin if suspecting MI)
If patient presents with acute LVF treat before confirmation with BNP or echo to avoid deterioration
What is cardiomegaly on a chest xray?
Cardiothoracic ratio of more than 0.5
This is when the diameter of the widest part of the heart (the wides part of the cardiac silhouette) is more than half the diameter of the widest part of the lung fields.
What can be seen on a CXR?
Cardiomegaly
Upper lobe venous diversion
Fluid leaking from oedematous lung tissue causes additional xray findings of:
Bilateral pleural effusions
Fluid in interlobar fissures
Fluid in the septal lines (Kerley lines)
What is the management of acute LVF?
Use the simple mnemonic Pour SOD for acute LVF:
Pour away (stop) their IV fluids
Sit up
Oxygen
Diuretics
Why should a patient sit upright when they have acute LVF?
When lying flat the fluid in the lungs spreads to a larger area.
When upright gravity takes it to the bases leaving the upper lungs clear for better gas exchange.
Why should patients with acute LVF be given diuretics?
This reduces the circulating volume and means the heart is less overloaded allowing it to pump more effectively.
What treatment options should be considered in severe acute pulmonary oedema or cardiogenic shock?
Intravenous opiates (opiates such as morphine act as vasodilators but are not routinely recommended).
Non-Invasive Ventilation (NIV) -Continuous Positive Airway Pressure (CPAP)
“Inotropes”, for example an infusion of noradrenalin.
Inotropes strengthen the force of heart contractions and improve heart failure, however they need close titration and monitoring, so by this point you would need to send the patient to the local coronary care unit / high dependency unit / intensive care unit.
