Recognising severe pneumonia with simple clinical and biochemical measurements.

Community-acquired pneumonia (CAP) is the most common reason for acute admission to hospital and the fourth most common cause of death in the UK. It is important to identify patients with severe pneumonia and the worst prognosis. We conducted this study to validate a rule designed to do this devised in New Zealand. CAP was defined by evidence of new shadowing on the chest X-ray and clinical features of pneumonia. A standardised proforma was completed documenting clinical features and investigation results. Severe pneumonia was identified by two or more of the following: confusion; respiratory rate > or = 30/min; diastolic blood pressure < or = 60 mmHg; urea >7 mmol/l. One hundred patients (mean age 58.8 years) were included; 32 satisfied the rule. Seven died, all of whom satisfied the rule. Ten patients received intensive care, including six who died. Of 11 patients who died and/or received intensive care, nine satisfied the rule. The sensitivity and specificity of the rule for predicting death and/or intensive care were 82% and 73% respectively.