INSTRUCTION

Examine this patient's chest.

SALIENT FEATURES

History

· Symptoms of COAD (see pp 261 6).

· Easy fatiguability, shortness of breath on exertion, weakness.

· Leg oedema, and right upper quadrant pain.

Examination

· Patient is short of breath at rest and is centrally cyanosed.

· Tar staining of the fingers.

· JVP is raised: both 'a' and 'v' waves are seen, 'v' waves being prominent if there is associated tricuspid regurgitation.

· On examination of the chest there is bilateral wheeze and other signs of chronic bronchitis (see pp 261-6).

Proceed as follows:

· Examine the cardiovascular system for signs of pulmonary hypertension:

-Left parasternal heave (often absent when the chest is barrel shaped).

-Right ventricular gallop rhythm.

-Loud P2 and a loud ejection click.

Pansystolic murmur of tricuspid regurgitation.

-Early diastolic Graham Steell murmur in the pulmonary area.

· Look for signs of:

- Hepatomegaly.

- Pedal oedema.

DIAGNOSIS

This patient has chronic cot pulmonale (lesion) due to long-standing COAD (aetiology) and is in congestive cardiac failure (functional

status).

QUESTIONS

What do you understand by the term 'cor pulmonale'?

Cor pulmonale is right ventricular enlargement due to the increase in afterload that occurs in diseases of the lung, chest wall or

pulmonary circulation.

Mention a few causes of cor pulmonale.

Respiratory disorders':

· Obstructive:

- COAD.

-Chronic persistent asthma.

· Restrictive:

-Intrinsic - interstitial fibrosis, lung resection.

- Extrinsic - obesity, muscle weakness, kyphoscoliosis, high altitude.

Pulmonary vascular disorders:

· Puhnonary emboli.

· Vasculitis of the small pulmonary arteries.

· Adult respiratory distress syndrome.

· Primary pulmonary hypertension.

ADVANCED-LEVEL QUESTIONS

How would you manage a patient with cor pulmonale?

· Treat the underlying cause.

· Treat respiratory failure. If Pao, is less than 8 kPa, administer 24% oxygen. There is no need for oxygen if Pa(), is more than 8

kPa. Monitor blood gases after 30 minutes. If PCO2, is rising (by I kPa), monitor blood gases hourly. If Pc(): continues to rise,

administer doxapram. If, in spite of this, the deterioration continues, the patient may merit artificial ventilation.

· Treat cardiac failure with furosemide (frusemide).

· Consider venesection if the haematocrit is more than 55% (Lancet 1989; ii: 20 1 ).

What is the prognosis in cor pulmonale?

Approximately 50% of patients succumb within 5 years.