Community-acquired pneumonia: severity of illness evaluation

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The pneumonia severity index

Fine and colleagues [6], [9] set out to develop a prediction tool that would identify accurately patients who have CAP at low risk for death within 30 days of presentation and who thus might be managed without hospital admission. Previous studies generally had been retrospective, sometimes based on features not available readily at admission [5], [6], [9] or on impractical complex scoring systems [9]. In addition, they usually were developed on single sites [10] and in hospitalized patient

The British Thoracic Society rule, CURB, and CURB65 scores

In 1987 the British Thoracic Society (BTS) published a prospective study of 453 adults who had CAP admitted to 25 hospitals in Britain [11]. One aim of the study was to identify prognostic factors for outcome by multivariate analysis to lead to simple prognostic rules for the identification of patients at high risk for adverse outcome, principally death. Three prognostic rules were constructed, of which the most useful, Rule 1, is known as the “BTS Rule.” The BTS Rule is based on the presence

The American Thoracic Society score

The 1993 American Thoracic Society (ATS) CAP Guidelines recognized that there was no universally agreed definition of severe pneumonia [25]. It therefore was proposed that the presence of at least one of seven features be used to define severe pneumonia, when admission to the ICU should be considered. When this rule was tested in a different prospectively collected population of 422 hospital admissions for CAP, of whom 64 (15%) were admitted to the ICU, several features had a weak relationship

Severity prediction rules in the elderly

Prediction of CAP severity in the elderly poses different challenges than in younger patients, but is important because of the higher mortality in this group. Many studies have shown that the clinical features of CAP may be different in the elderly. Therefore, severity prediction may need to be based on different parameters than those in the young. The issue is complicated further, however, by differences in the way in which management interventions might be applied to the elderly, which makes

Comparison of severity of illness scores

Comparisons between scoring systems in the elderly have been described. The study that derived and validated the CURB65 score made a direct comparison with the PSI [20]. The two systems were comparable for mortality prediction when the PSI was reorganized into three groups (Fig. 6). In a study of 731 unselected and consecutive CAP admissions to a tertiary care center, of whom 17% were admitted to the ICU and 7% died, the BTS rules were compared with the ATS rule, a sepsis score, and the PSI [17]

Do severity-of-illness scores alter management and outcome?

Whether severity-of-illness scores alter management and outcome is perhaps the most critical question, because if the application of an illness severity score does not alter outcome, then its value in clinical practice must be questioned. The development of illness severity scores is evolving, so it is not surprising that few studies have addressed this issue. Table 2 summarizes available studies.

All these studies have limitations. In most, the retrospective cohort design (when applied to

How should severity-of-illness scores be used?

Because of the shortage of prospective studies evaluating illness-severity scores, it is difficult to determine how such scores should be used. The weakness of clinical judgment alone in severity prediction, however, and the poor management of medical patients before ICU admission argue that validated scoring systems are likely to help. These only should be used, however, to complement clinical judgment, and not indiscriminately in isolation. Further evolution of the scores and their operating

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References (44)

  • P. McQuillan et al.

    Confidential inquiry into quality of care before admission to intensive care

    BMJ

    (1998)
  • E. Seward et al.

    A confidential study of deaths after emergency medical admission: issues relating to quality of care

    Clin Med

    (2003)
  • J. Daley et al.

    Predicting hospital-associated mortality for Medicare patients. A method for patients with stroke, pneumonia, acute myocardial infarction, and congestive heart failure

    JAMA

    (1988)
  • A. Durocher et al.

    A comparison of three severity score indexes in an evaluation of serious bacterial pneumonia

    Intensive Care Med

    (1988)
  • C. Feldman et al.

    Community-acquired pneumonia of diverse aetiology: prognostic features in patients admitted to an intensive care unit and a ‘severity of illness’ score

    Intensive Care Med

    (1989)
  • M.J. Fine et al.

    Comparison of a disease-specific and a generic severity of illness measure for patients with community-acquired pneumonia

    J Gen Intern Med

    (1995)
  • A. Ortqvist et al.

    Aetiology, outcome and prognostic factors in community-acquired pneumonia requiring hospitalization

    Eur Respir J

    (1990)
  • British Thoracic Society

    Community-acquired pneumonia in adults in British hospitals in 1982–1983: a survey of aetiology, mortality, prognostic factors and outcome

    Q J Med

    (1987)
  • M.J. Fine et al.

    A prediction rule to identify low-risk patients with community-acquired pneumonia

    N Engl J Med

    (1997)
  • J. Dedier et al.

    Processes of care, illness severity, and outcomes in the management of community-acquired pneumonia at academic hospitals

    Arch Intern Med

    (2001)
  • G.W. Waterer et al.

    Monotherapy may be suboptimal for severe bacteremic pneumococcal pneumonia

    Arch Intern Med

    (2001)
  • D.C. Angus et al.

    Severe community-acquired pneumonia: use of intensive care services and evaluation of American and British Thoracic Society diagnostic criteria

    Am J Respir Crit Care Med

    (2002)
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