To assess respiratory reserve (Box 4.1), it is important to determine how well the patient can move air, assessed at the bedside or by spirometry with forced vital capacity testing. A forced expiration time (FET) of less than three seconds is normal. A time of more than five seconds is abnormal and indicates significant obstructive airways disease, as does inability to blow out a match held at 15 cm from the mouth. Obstructive airways disease is by far the most common type of lung disease seen. It occurs as part of the degenerative effects of ageing and is exacerbated by smoking.

The other main type of lung disease is restrictive disease, resulting from conditions that restrict or destroy lung tissue. Pulmonary atelectasis, oedema, effusions and infections are the most common causes seen in post-surgical patients. Counting while breath-holding should be possible for at least 20 seconds. Inability to do so suggests significant restrictive lung disease.

Pulmonary function tests (PFTs) augment the bedside tests and are used to define the degree of respiratory dysfunction on presentation, the amount of functional respiratory reserve and hence the ability to tolerate lung surgery and, at follow-up, the response to therapy. There are two major types of PFT:

• those that assess the movement of air in and out of the lungs (e.g. forced expiratory volume in one second, forced vital capacity, peak flow, total lung capacity, residual volume)

• those that measure the ability to transfer gas across the alveolar–capillary membrane (e.g. tests of carbon monoxide diffusing capacity).

When considering surgical therapy for a given patient, it may be evident that the patient has insufficient ventilatory reserve to cope with a chest wall incision or a major pulmonary resection and alternative non-operative therapies will need to be offered.

Arterial blood gas analysis is also an important investigation in patients with acute and chronic thoracic conditions. Parameters measured include PaO2, pCO2, pH, bicarbonate level and arterial oxygen saturation.

History

Breathlessness, chest pain, palpitations and cough are cardinal symptoms of cardiorespiratory disease.

Breathlessness on exertion is a feature of both cardiac and respiratory disease and is also seen in the severely anaemic patient. Dyspnoea at rest is more characteristic of heart failure (‘cardiac asthma’) than of chronic pulmonary disease. With cardiac disease, dyspnoea is of variable severity, not usually associated with wheeze or productive cough and may be nocturnal as well as exertional. The heart will usually be enlarged. Ankle oedema also strongly suggests heart failure.

Breathlessness on sudden awakening is called paroxysmal nocturnal dyspnoea, which is sometimes the initial symptom of congestive cardiac failure. By contrast, obstructive lung disease presents with exertional dyspnoea of insidious onset, a wheeze associated with prolonged expiration and an ineffective and productive cough. Paroxysmal nocturnal dyspnoea can simulate bronchial asthma first appearing in adult life or the symptoms of regurgitation and nocturnal aspiration of gastric juice in patients with reflux oesophagitis.

Marked fatigue relieved by rest is common in heart failure and in some instances may be the main complaint. Fatigue and lethargy due to chronic depression are not relieved by rest.

Any chest pain must be assessed carefully. In ischaemic heart disease, anginal pain is due to coronary artery narrowing or occlusion. Non-cardiac causes of chest pain are also common.

Cardiac pain is retrosternal, described as constricting or crushing, and may radiate to the neck or shoulders and arm. The pain may be brought on by exertion (angina of effort) or be continuous, suggesting myocardial infarction. Patients with angina can be classified using the New York Heart Association (NYHA) classification, as shown in Table 4.1.

Table 4.1 New York Heart Association classification of angina

Class	Description
I	Angina with strenuous exercise
II	Angina with moderate exercise
III	Angina after climbing one flight of stairs or walking one or two blocks
IV	Angina with any activity

Elective surgery is permitted in patients with Class I and Class II angina but is usually contraindicated with Class III or IV angina. In these latter cases, coronary angiography and percutaneous coronary intervention (PCI) or coronary bypass grafting may be considered before major elective surgery.

Pleuritic pain arises from inflamed pleura, is described as sharp or stabbing and is made worse by deep breathing and coughing.

Awareness of the action of the heart (palpitations) suggests cardiac disease. This symptom must be defined as accurately as possible. The patient may be aware of a fast or slow pounding of the heart, a sensation of a missed or irregular beat or a fluttering in the chest. The symptom can occur in normal individuals after exertion or from anxiety. Syncope may occur. If the symptom has not been precipitated by such obvious causes, an arrhythmia should be excluded.

Cough is the most common and prominent symptom of respiratory disease. Paroxysmal coughing suggests bronchial obstruction. The integrity of the cough reflex is essential if sputum retention is to be prevented in the perioperative period.

Wheezing is a characteristic symptom of bronchial narrowing, occurring during expiration in chronic obstructive airways disease and paroxysmally and throughout the breathing cycle in bronchial asthma.

Haemoptysis can occur in many bronchopulmonary diseases, including bronchitis, tuberculosis, carcinoma and bronchiectasis. Haemoptysis associated with acute pleuritic chest pain suggests pulmonary embolus and infarction.

A careful enquiry should always be made about past and present medications taken by the patient and any allergy to such medications. This should include drugs prescribed, bought over the counter and ‘alternative’ medicines. Of particular importance are cardiac drugs and those with effects that might influence the safety of surgery, including insulin and oral hypoglycaemic drugs, oral contraceptives, diuretics, digitalis, beta-blocking agents and other antihypertensives, uricosuric drugs, anti-anxiety (phenothiazine) drugs, antidepressants, sedatives and aperients. The past history may reveal relevant illnesses such as asthma, tuberculosis, bronchiectasis, rheumatic fever or occupations of significance and allergies. Smoking habits and alcohol intake must be noted. Actions to diminish intake during preoperative preparation (which can minimise and reverse cardiorespiratory damage) must commence as soon as possible.

Physical examination

General inspection

The patient’s general appearance often assists in the diagnosis of cardiorespiratory disease. Central or peripheral cyanosis, the pallor of anaemia, laboured breathing with the use of accessory neck muscles and pursing of the lips on expiration (diagnostic of chronic obstructive airways disease) and obesity are all relevant.

Inspection of the sputum can reveal the frothy pink sputum of acute left ventricular failure, the purulent or white sputum of bronchitis and bronchiectasis or the rusty sputum of pneumonia. Haemoptysis occurs with chronic bronchitis, tuberculosis, pulmonary infarction or carcinoma of the lung. Copious purulent, offensive sputum suggests lung abscess.

Examination of the periphery

Peripheral cyanosis with cold skin suggests low cardiac output, peripheral vascular disease or vasospasm. Cyanosis with warm skin suggests venous shunting. Warm hands without cyanosis, on a cold day, suggest thyrotoxicosis.

Clubbing or thickening of tissues over the terminal phalanx with rocking of the nail is found in cyanotic congenital heart disease, chronic pulmonary suppuration, lung cancer, inflammatory bowel disease, cirrhosis of the liver and thyrotoxicosis and is occasionally found as a congenital trait. Clubbing can be graded in severity (Table 4.2).

Table 4.2 Grades of finger clubbing

Grade I	Obliteration of the normal angle between nail and cuticle
Grade II	Soft tissue thickening with nail breaking in anteroposterior plane
Grade III	Thickening also in a lateral plane

Nicotine staining on the fingers is an important physical sign suggesting the likelihood of respiratory or vascular disease.

	Venous	Arterial
Easily palpable	No	Yes
Visible but not palpable	Yes	No
Waves per cycle	Two	One
Changes with respiration and valsalva	*Yes	No
Changes with compression of neck and abdomen	*Yes	No
Changes with posture	*Yes	No

* If vena cava unobstructed

If there is elevation without a venous pulse wave and no fall on sitting to 90°, superior vena caval obstruction is probably present.

Examination of the heart

After inspection of the chest wall the strength of the cardiac impulse is assessed and the apex beat located by palpation. The apex beat is normally in the left fifth intercostal space in the mid-clavicular line, 7–12 cm from the left sternal edge. The apex beat may not be felt in the obese or emphysematous patient. Lateral displacement of the apex beat indicates left ventricular hypertrophy, especially when vigorous and sharply localised. An enlarged right ventricle causes little displacement of the apex beat; its pulsation is felt best at the left sternal edge. Vibrations or thrills may be felt corresponding to audible heart murmurs.

Auscultation is performed over the precordium, examining each phase of the cardiac cycle and using different positions to assist in interpretation. Starting at the apex, auscultation may reveal additional heart sounds, extracardiac sounds or clicks and murmurs due to turbulent flow within the heart. Murmurs are graded according to intensity. A soft short systolic murmur at any valve area may be innocent if there are no other abnormalities, especially if the murmur disappears during respiration or with a change in posture. Anaemia may cause a flow murmur related to an increased cardiac output consequent upon a decrease in oxygen-carrying capacity of the blood. Diastolic murmurs are not found in healthy subjects. The areas where murmur are best heard are: the aortic area at the right second costochondral junction and down the left side of the sternum — especially on leaning forward and in expiration; the pulmonary area at the left second interspace; the tricuspid area at the left fourth interspace; and the mitral area at the apex — especially when the patient is turned on to the left side.

Systolic murmurs are produced by valvular diseases, mitral incompetence and aortic sclerosis/stenosis or by ventricular septal defects. Fever, anxiety and pregnancy may sometimes induce benign systolic murmurs. The louder a systolic murmur, especially one associated with a thrill and cardiomegaly, the more likely it is to be of organic origin. An early systolic murmur that replaces the first sound and is transmitted into the left axilla is organic and is due to mitral incompetence and regurgitation. The aortic systolic murmur of aortic stenosis is ejection in type, midsystolic and is transmitted into the neck. Diastolic murmurs are caused by aortic incompetence, mitral stenosis or dilatation of the aortic ring in patients with marked hypertension and intracardiac shunt. The mitral stenotic murmur is diastolic with a presystolic crescendo component (unless there is atrial fibrillation) and is preceded by an opening snap, often best heard with the patient lying on the left side. The aortic incompetent murmur is in early diastole and is best heard with the patient leaning forward and holding the breath in expiration.

Finally the abdomen and legs are examined.

Congestive cardiac failure (CCF) is a very common medical problem encountered in surgical patients and includes left and right ventricular failure.

Left ventricular failure (Table 4.4) is characterised predominantly by symptoms such as exertional dyspnoea, cough, fatigue orthopnoea and paroxysmal nocturnal dyspnoea. Fatigue may be the chief complaint in patients with heart failure from mitral valve disease. The signs include cardiomegaly, basal crepitations in the lungs, gallop rhythm (a cadence found with tachycardia plus triple rhythm due to a loud, easily heard, third heart sound) and evidence of pulmonary venous congestion on X-ray (Kerley B lines).

Table 4.4 Clinical manifestations of heart failure

	Left	Right
Symptoms	Dyspnoea	Dyspnoea
	Cough
	Orthopnoea
	Paroxysmal nocturnal dyspnoea
Signs	Cardiomegaly	Elevated venous pressure
	Gallop rhythm
	Basal crepitations	Oedema
		Hepatomegaly