Acute heart failure (acute pulmonary oedema)

Clinical features

– Onset or sudden exacerbation of dyspnoea
– Anxiety, agitation
– Peripheral oedema 
– On auscultation: wet rales in both lung fields, sometimes muffled heart sounds and/or cardiac gallop.

Signs of severity:
– Severe respiratory distress (intercostal retractions, nasal flaring, see-saw breathing, SpO2 < 90% while breathing ambient air), cyanosis, profuse sweating, confusion
– Systolic blood pressure < 90 mmHg 
– Heart rate (HR) > 150/minute or < 40/minute
– Respiratory rate (RR) > 30/minute or < 12/minute 
– Chest pain if underlying cardiac ischemia

Paraclinical investigations

Diagnosis is mainly clinical.
− ECG: look for signs of myocardial ischemia or arrhythmia.
If available:
− Chest X-ray: signs vary depending on the severity of pulmonary oedema: dilation of vessels in upper lobes then perifilar haze and thickening of septa. In advanced stage HF, prominent shadow in hilar and perihilar regions. Can exclude pulmonary infection.
– Lung and pleural ultrasound: presence of B-lines, presence of bilateral pleural effusion
– Electrocardiogram: look for signs of circulatory overload 

Monitoring: blood count, ionogram, serum creatinine

Treatment

Systolic blood pressure is < 90 mmHg

See Shock, Chapter 1.

Systolic blood pressure is ≥ 90 mmHg  

Treatment common to all patients: 
– Place patient is semi-seated position, legs down 
– Oxygen mask, 6-10 litres/minute 
– Insert an IV line
– Diuretic: furosemide IV, 40 mg to be repeated once if the patient has not urinated within 30 to 60 minutes. If the patient was already taking furosemide at doses of > 40 mg, administrer his usual dose by IV route.
– Monitor: HR, RR, BP, SpO2, mental status

Other treatments :
– Add an immediate-release nitrate (vasodilator) if systolic blood pressure is ≥ 180 mmHg and/or diastolic ≥ 110 mmHg.
The objective is to lower the systolic blood pressure to 120-150 mmHg and the diastolic pressure to under 110 mmHg.
isosorbide dinitrate IV (10 ml ampoule, 1 mg/ml)
2 mg (= 2 ml) by slow IV injection (over 2 minutes) then if necessary 2 to 10 mg/hour by continuous infusion with an electric syringe
Use sublingual route if IV route is not feasible:
isosorbide dinitrate sublingual (5 mg tablet)
5 mg per dose; if necessary up to 2 doses taken 10 minutes apart, on condition that systolic blood pressure is > 120 mmHg
or glyceryl trinitrate, sublingual (0.5 mg tablet)
0.5 mg per dose; if necessary up to 3 doses taken 5 minutes apart, on condition that systolic blood pressure is > 120 mmHg
– In patients with severe dyspnea, a nitrate can be considered if breathing does not improve 10 minutes after the adminstration of oxygen and furosemide. Treatment is only administered if the systolic blood pressure is > 120 mmHg. 

Subsequent treatment depends on the underlying pathology (chronic heart failurehypertension, acute coronary syndrome, etc.).