The differential diagnosis of chest pain
VOL: 98, ISSUE: 50, PAGE NO: 30
Julia Hubbard, MSc, BSc, PGDE, DipN, RGN, is adult branch leader, School of Nursing and Midwifery, University of East Anglia, NorwichChest pain is a frequent complaint of patients seeking urgent medical assistance, and accounts for an estimated 2-4 per cent of all A&E visits in the UK (Becker, 2000). Generally, acute chest pain should be considered cardiovascular in origin until proven otherwise and it is common in clinical practice to err on the conservative or 'safe' side when evaluating people with chest pain.
Chest pain has many causes, and it can be challenging for nurses to determine its aetiology. It is important to bear in mind that the complaint is partly determined by cultural factors influencing an individual's interpretation of physiological pain (Clancy and McVicar, 2002) and, therefore, a chest pain history plays a major role in the differential diagnosis. As a reminder, it is of utmost importance to recognise that chest pain may originate not only in the heart but also in a variety of non-cardiac intrathoracic structures. Potential causes of chest pain fall loosely into the following groups: - Cardiac: myocardial infarction, unstable angina, acute pericarditis, coronary spasm, hypertrophic cardiomyopathy, anaemia, myocarditis, aortic dissection and pulmonary hypertension; - Pulmonary: pulmonary embolism, pneumonia, pleuritis and pneumothorax; - Gastrointestinal: oesophageal reflux/spasm, oesophageal rupture and biliary colic; - Musculoskeletal: fractured rib, costochondritis (an inflammation of the costal cartilage of the anterior chest wall, characterised by pain and tenderness), chest wall trauma and Herpes zoster; - Miscellaneous: anxiety/panic attacks, depression, cocaine use and lymphoma, for example. Prior to performing laboratory or other diagnostic tests it is important to undertake a thorough assessment of patients who present with chest pain. The aim of this assessment is to determine: - The location, radiation and characteristics of the chest pain; - What precipitates and relieves the pain; - The setting in which the pain occurs; - The duration, frequency and pattern of the episodes of pain; - Any associated symptoms. Table 1 provides an overview of the differential characteristics of the three most common causes of chest pain, to assist with assessment and diagnosis. The amount of time spent asking questions will depend on the patient's condition, but even in the most urgent cases nurses should attempt to determine some basic facts. To this end a pain assessment list may be useful, such as Burden and Rogers' (1986) seven-question chest pain assessment. 1. How do you feel? Describe the sensation. 2. Where does it hurt? 3. Does the sensation travel elsewhere? 4. Did anything trigger it off? 5. How long has it lasted? 6. Has anything made it better or worse? 7. Are there any other relevant signs and symptoms? This list alone will not give any information on the patient's subjective experience of the pain, and it should be used in conjunction with an appropriate pain assessment tool. Alongside the chest pain history and physical examination, the electrocardiogram is the single most valuable and immediate diagnostic tool to help determine whether cardiac causes can be ruled out. When the ECG is inconclusive, additional evidence to confirm a cardiac origin can be made by detecting raised plasma activities of cardiac enzymes. Particular attention is paid to the enzymes CKMB (a variant of creatine kinase) and troponin (Hubbard, 2002). New developments
The National Service Framework for Coronary Heart Disease (DoH, 2000) has recommended that by 2003 there should be 100 rapid access chest pain clinics across the country. This should ensure that when patients develop new chest pain symptoms - which their GPs think might be due to cardiac origins - they can be referred directly to the acute services for rapid assessment by a specialist (usually a clinical nurse specialist). The framework also proposed that, from April 2002, 75 per cent of eligible patients (that is, people with cardiac chest pain due to myocardial infarction) should receive thrombolysis within 30 minutes of arrival in hospital. From April 2003, the target will be to treat 75 per cent of eligible patients within 20 minutes of arrival at hospital. Thus, the role of the nurse in the differential diagnosis of chest pain looks likely to continue expanding. Conclusion
It is important that patients presenting with chest pain are rapidly and skilfully assessed so that the correct working diagnosis can be made and appropriate treatment offered. Nurses will play an increasing role in the differential diagnosis of chest pain and should be familiar with correct procedures and practice. It is, therefore, valuable to remember the following points: - A quick assessment is important if myocardial infarction seems possible and there is a view to put the patient on a fast track to thrombolytic therapy; - The patient's history is usually more helpful than the physical examination; - In almost all diseases that cause chest pain, the physical examination of patients can at times show nothing abnormal, apart from the signs that are the result of the pain itself. Perhaps of greatest importance is that nurses should never underestimate the signs, symptoms, and reports of feeling 'unwell' that prompt an individual to seek medical attention and ask for help.