Ageing and the Cardiorespiratory System

Original Editor - Simisola Ajeyalemi

Top Contributors - Simisola Ajeyalemi, Lucinda hampton, Sai Kripa, Shaimaa Eldib and Kim Jackson  

Introduction

Ageing refers to the physiological changes that occur in the human body from the attainment of adulthood, and ending in death. These changes involve a decline of biological functions, and are accompanied by psychological, behavioral, and other changes. Some of these changes are quite obvious, while others are subtle.

Respiratory System

Age-related changes in the respiratory system primarily arise from the loss of elasticity and a decline in chest wall compliance, making an increase in work of breathing, residual volume and functional residual capacity. Alveoli coalesce from atrophy and loss of elasticity. Additionally there is reduction of sensitivity and efficiency of self-cleansing mechanism as bronchial epithelium and mucous glands degenerate. Arterial oxygen tension falls from 95mmHg (12.7kPa) at age 30 to 75mmHg (10kPa) at age 60.Osteoporosis affects thoracic vertebrae and rib cage increasing rigidity of the chest wall. There is reduced elasticity and calcification of costal cartilages, weakness of intercostal and accessory muscles of respiration resulting in impairment of functional reserve capacity (clinical evidence is minimal unless evoked by illness). Compliance changes little because the rise to be expected from diminished elastic recoil is offset by increased lung stiffness (fibrosis) and loss of flexibility in chest wall.

Together these changes lower an older persons threshold in compensating for an acute disorder eg Pneumonia or Respiratory Failure

Cardiovascular System

Aging decreases the threshold for developing cardiovascular disease. This is essentially due to loss of cardioprotective and compensatory mechanisms that in younger years aide in prevention of cardiac disease development. Changes include:

• Aorta – loss of elasticity plus hyperplasia leads to dilation and unfolding that may obstruct venous return.
• Cusps of heart valves degenerate, with murmurs more detectable, although not necessarily significant.
• Myocardial changes – lipofuscin deposits, myocardial fibrosis and amyloidosis. Atrophy and fibrosis of media, intimal hyperplasia in coronary arteries. This leads to reduced cardiac output (from reduced stroke volume) leading to a given amount of exercise raising heart rate and blood pressure more than in youth.
• Atheroma incidence increases with age, probably promoted by hypertension and cigarettes. Mental confusion and profound weariness should raise suspicion of heart disease in older people. They are often more prominent than angina pain or even breathlessness because of restricted activity.

These ageing changes may lead to Cardiovascular Disease. For example:

• Cardiovascular Disease, the leading cause of death for both males and females.
• Atherosclerosis.
• Arteriosclerosis.
• Coronary Artery Disease.
• Stroke
• Heart Failure

Treatment

In people with heart failure, you will need to watch positioning, as they may not tolerate the supine position. Be aware, when treating a chest condition, of the signs and differences between cardiac failure and a chest infection, as we are limited in what we can do with the former complaint compared to the latter.

Circulation- It is important to consider the person’s general sensation and circulation , especially in conditions such as intermittent claudication, neuropathy, Raynaud’s phenomena, and ulceration.

Decreased exercise tolerance and increased fatigue can be secondary to these changes. Your assessment must ascertain the person's prior level of function, so that they can set appropriate goals and progress in a timely fashion. This should also take into account any growing fears, whether chest or heart related, as either will make the individual breathless and anxious about the effect of exercising. You may need to have heart or saturation monitors available during treatment, or at the very least, medications such as GTN spray for angina attacks or inhalers for relief of bronchospasm with chronic respiratory conditions. If conducting a Cardiac Rehabilitation class, ensure you know who is at hand with CardioPulmonary Resuscitation experience.

Watch the work of breathing- it is an indicator of exertion, and ensure adequate recovery time with treatments, whether rehabilitation or of an acute chest problem. There may be an element of acute confusion in those with hypoxia. You may find those with a chronic chest have developed their own coping strategies for breathlessness; don’t ignore these or try to alter them straight away.

Resources

Ageing and the Cardiorespiratory System