Sun21November0452PM 1

A 54-year old woman was admitted with acute breathlessness.

On examination, she had a temperature of 37°C, a respiratory rate of 32 breaths per minute, a pulse of 120 beats per minute, a blood pressure of 100/60 mmHg, and a peak expiratory flow rate of 250 litres per minute.

Auscultation of the heart and chest was normal.

The chest x ray was normal and blood gases on air showed:

pH 7.35 (7.36-7.44)

PaO2 6.0 kPa (11.3-12.6)

PaCO2 3.9 kPa (4.7-6.0)

Serum bicarbonate 20 mmol/L (20-28)

She was started on high flow oxygen.

Which of the following is the most important next treatment?

(Please select 1 option)

Intravenous fluids

Amoxicillin intravenously

Nebulised salbutamol

Low molecular weight heparin (LMWH) Correct

Aminophylline intravenously

Explanation

This patient has features of a type 1 respiratory failure with mixed acid-base disturbances.

The differential diagnosis here lies between pulmonary embolism (PE) and acute severe asthma.

On the basis of the reasonable peak expiry flow rate (PEFR) of 250, the tachycardia, and hypotension, PE seems the more likely explanation and LMWH would be the treatment of choice.

Intravenous (IV) fluids are potentially harmful since the cause of the shock is an obstructed right ventricle. Fluids may dilate the ventricle further and reduce cardiac output.

There is a role for fluids in those patients with rapidly falling blood pressure but this should preferably be done (if there is time) with central pressure monitoring.

Answer Statistics

1

7%

2

3%

3

40%

4

52%

5

1%

Times answered: 280