Acute LVF and Pulmonary Oedema Flashcards
ESSENCE
Left ventricle is unable to adequately move blood through the left side of heart and out into body, causing backlog in the left atrium, pulmonary vein and lungs
This causes pulmonary oedema which interferes with gas exchange
AETIOLOGY
Triggers
- Iatrogenic (eg aggressive IV fluids in frail patient)
- Sepsis
- MI
- Arrhythmias
CLINICAL FEATURES
Presentation
- Typically rapid onset breathlessness
- Exacerbated by lying flat and improves on sitting up
- Cough
- Frothy white/pink sputum
- Looking and feeling unwell
- Maybe features of underlying cause
- Chest pain in ACS
- Fever in sepsis
- Palpitations in arrhythmias
CLINICAL FEATURES
Signs
- Increase respiratory rate
- Reduced oxygen saturations
- Tachycardia
- 3rd Heart Sound
- Bilateral basal crackles (sounding “wet”) on auscultation
- Hypotension in severe cases (cardiogenic shock)
Signs of 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)
INVESTIGATIONS
Diagnosis
- Treat before confirming diagnosis with BNP or ECHO
INVESTIGATIONS
First choice
- ECG - look for ischaemia and arrhythmias
- Arterial blood gas
- Chest x-ray
- Bloods (routine for infection, kidney function, BNP and maybe troponin if suspecting MI)
What is B-type natriuretic peptide (BNP)
Hormone released from heart ventricles when cardiac muscle (myocardium) stretched beyond normal range, high result indicates heart is overloaded with blood beyond normal capacity to pump effectively
Action of BNP
Relax smooth muscle in blood vessels > reduces systemic vascular resistance making easier to pump blood
Acts on kidneys as diuretic (promote excretion of more water in urine) > reduces circulating volume
Causes of raied BNP
- Is sensitive but not specific
- Tachycardia
- Sepsis
- Pulmonary embolism
- Renal impairment
- COPD
Normal ejection fraction
>50% considered normal
Chest x-ray findings
- Cardiomegaly
- Upper lobe venous diversion
- Due to fluid leaking from oedematous lung tissue
- Bilateral pleural effusions
- Fluid in interlobar fissures
- Fluid in septal lines (Kerley lines)
What is cardiomegaly on chest xray
- A cardiothoracic ratio > 0.5
- Diameter of widest part of heart more than half diameter of widest part of lung fields
MANAGEMENT
General principles
- Remember PourSOD
- Pour away (stop IV fluids)
- Sit up
- Oxygen
- Diuretics
- IF severe acute pulmonary oedema or cardiogenic shock
- IV opiods
- Non-invasive ventilation (NIV) continuous positive airway pressure (CPAP)
- Inotropes
Why are IV opiates used in severe disease
Morphine act as vasodilators
