History taking and clinical examination can provide an accurate assessment of severity of illness and social support available in the community. Although most patients with LRTI are managed in the community without investigations,¹⁸ some clinical assessment may help predict the need for hospitalisation. It is good clinical practice to examine the chest and make basic observations.

Occasionally, patients will present with a severe form of LRTI, i.e. pneumonia. No combination of symptoms or clinical findings reliably confirms the diagnosis of pneumonia. If focal chest signs are present, 35-46% of patients may have pneumonia.¹⁹ In the elderly, clinical features are less reliable, and up to 50% of pneumonia cases cannot be diagnosed from clinical symptoms.

Studies suggest that between 70 and 99% of community acquired pneumonia is managed at home.^20,21 Severity assessment tools have been developed to aid the primary care or A&E physician to safely predict those patients who can be managed at home; and decreased admission rates, without increased mortality, have been demonstrated when such admission decision protocols are used.²² Evidence level 3

Evidence from the USA has shown that patients with radiological evidence of pneumonia who do not exhibit any of the features shown in Box 1 have a negligible mortality and can normally be managed in the community.²³ Evidence level 2+

Box 1: Features of severity in LRTI (items in bold are the most important) Raised respiratory rate (>30/min) Low blood pressure (systolic <90 mmHg +/- diastolic <60 mmHg) Confusion of recent onset Age >50 years Coexisting disease present (e.g. cardiac failure, cerebrovascular, neoplastic, renal, or liver disease) High or low temperature (<35°C or >=40°C) Tachycardia (>125/min)

Clinical judgement will also need to be taken into account. There will for instance, be patients over the age of 50 who could be managed safely at home, and indeed other workers have proposed similar criteria but with age >65.²⁴ It also needs to be borne in mind that what applies in North American healthcare does not necessarily apply to a Scottish population. Therefore such criteria may guide the physician in the prognostic factors to look for, but cannot be interpreted rigidly, the decision being dependent on a more holistic overview of the patient. Evidence level 3

The decision for hospitalisation should also consider social factors. Even a relatively "well" patient who is socially disadvantaged or geographically isolated may require hospital rather than community care.²⁵ Similarly, domiciliary treatment may not be appropriate for a frail isolated elderly patient with co-morbidity, or where compliance is unpredictable, for example in patients who have severe psychiatric disorder or who have an alcohol problem. Hospital admission may be needed if there is lack of social support, inability to take medicine (e.g. vomiting), or where illness is assessed as severe.

Manage patients with LRTI routinely in the community, using assessment protocols based on the features of severity to identify those requiring hospital admission. Consider the individual patient's needs and the availability of support at home.