In relation to the data below Relate the signs and symptoms of the patient below to their underlying pathophysiological changes of heart failure. Explain the possible hazards of oxygen therapy in this patient.
60 year old male, had an myocardial infarction several years ago.
Bilateral leg oedema up to his calf and shortness of breath on exercise.
Has a heart rate of 100 beats per minute, and arterial blood pressure of 100/60 mmHg. Patient has an inlarged heart.
Arterial blood sample of patient:
Pco2 = 7.2 kPa (4.8 - 6.1)
P02 = 7.0 kPa (10.0 - 13.3 )
Ph = 7.29 (7.36 - 7.44)
Exhocardiography revealed severe left ventricular dysfunction with an ejection fraction of 32%. Coronary angiography showed complete occlusion of the right coronary artery 40mm distal to its origin, and diffuse, non occlusive disease in the major branches of the left artery.
Patient family history: both parents died at around 60 years of age. Two brothers who are smokers have been admitted to hospital for cardiac problems.
Patient has been smoking 30 cigarettes a day since he was 17 .
Patient has been suffering from from angina pain on mild exertion and been radiating down left arm even at rest. Need to sleep at night with raised pillows but wakes up due to feeling breathless.
This man has an extensive family history of cardiovascular disease. There is therefore a clear genetic background to his condition. On top of that he is also since early youth a rather heavy smoker which further increases his cardiovascular risks. he is known to have had a myocardial infarction previously as a result of his condition and which obviously has made it worse. Due to decreased heart function - most probably after his infarction - he has typical symptoms of cardiac insufficiency (a kind of heart failure though obviously not complete or he would be dead). These symptoms include bilateral leg oedema up to his calf, shortness of breath on exercise, tachycardia (high heart rate at rest) and that he must have his head high while sleeping and yet he wakes up at night due to shortness of breath. Another sign is his rather low blood pressure. As a sign of cardiosclerosis (probably a part of a general arteriosclerosis) he has angina pain even at mild exercise and even some down his left arm at rest.
Examinations have shown an enlarged heart, a severely decreased function of his left heart ventricle where only 32% of the normal blood volume is ejected during heart contraction. His heart rate (presumably at rest) is a hundred per minute and his blood ...