
Home Research Community acquired pneumonia Pre-op screening Legionella detection Virtual Sentinel Node Falls Risk Assessment CV Line Cost Benefit Health Systems Analysis Topics Courses People Links

Health Informatics Unit
The University of Adelaide
SA 5005 Australia
Email

Telephone:
+61 8 8274 3713
Facsimile:
+61 8 8271 9158

Guidelines for the Treatment of Community Acquired Pneumonia (CAP)

Scott Clark

Health Informatics, Adelaide University

Guidelines in CAP [1]

Some variation in clinical practice is required due to both patient and disease complexity, however a proportion of this variation may be associated with sub-optimal outcomes and adverse events. Consequently, excess mortality, morbidity and cost may be explained by the high variation in pneumonia treatment practices [2] . Studies of clinical practice processes and outcomes have indicated this trend exists worldwide [ 3 4 ].

In recent times the management response to practice and outcome variation has been the paper-based guideline. For CAP alone 30 guideline articles have been published during the past decade [5] , culminating in consensus statements from major organisations in pulmonary and infectious medicine, such as the British Thoracic Society [6] , The American Thoracic Society [7] and the Infectious Diseases Society of America [8] .

CAP is highly heterogeneous disease. It has multiple aetiologies and treatments. Comorbidity modifies risk of infection, course and outcome of the disease. CAP treatment is also complicated by a continuum of severity. Care for CAP patients spans the whole health system from primary care to ICU. Consequently, CAP consensus statements tend to be large impractical documents that attempt to cover all the major decisions for the treatment of a disease. They identify standards for diagnosis and investigation of microbiological aetiology. They indicate specific empiric treatments for differing sub-groups of patients [8] . Due to the poor sensitivity and specificity of microbiological investigations in CAP [8] and the association of treatment delay with poor outcomes [9] , consensus statements identify preferred antibiotics based on their spectrum of action against locally prevalent microbes, modified by patient risk factors and the severity of disease [8] .

Broad consensus documents are then adapted and simplified by local institutions. This reflects the need to produce a usable guideline of low complexity, the stakeholders involved local guideline construction and the quality of the evidence available. An example is the CAP guideline recently implemented at an Australian teaching hospital. This guideline is based upon the Intermountain Health CAP guideline, which in turn is derived from the American Thoracic Society 1993 consensus statement. [10]

Performance of Guidelines in CAP

To date there is only one randomised controlled clinical trial of pneumonia guideline efficacy [11] .

This guideline consisted of a clinical prediction rule for admission, levofloxacin therapy, and a critical pathway including criteria for switch from intravenous to oral antibiotics and discharge.

Implementation resulted in an 18% reduction in the admission of low risk patients, a reduction of 1.7 bed days per patient managed (6.1 to 4.4 days), and a mean reduction of 1.7 days of intravenous therapy (6.3 to 4.6 days), in comparison to conventional management. These figures represent significant savings. Fifty Nine percent of the cost of treating pneumonia is associated with staffing and room costs and it is estimated that a 1 day reduction in length of stay would result in a mean saving of $US 680 per patient [12] .

Only one study has shown a significant reduction in mortality, from 13.4% to 11% following CAP guideline introduction [10]

Other prospective studies have indicated reduced hospitalisation rates for low-risk patients [13] , and earlier switch from intravenous to oral antibiotics and earlier discharge for low risk patients [14 15 ]. Guidelines may also produce significant savings in mean antibiotic costs of around $US13 per patient for non-severe patients [16] and reduce symptoms at 6 weeks post therapy [17] .

These studies indicate that there are substantial gains in health outcomes and resource usage to be made by the implementation of CAP guidelines. These gains may only be the "tip of the iceberg" when the inadequacies of the guideline construction process and the applicability, usability and use of guidelines themselves are considered.

Problems With Guidelines

Due to the difficulty and cost of interpreting the evidence base, guidelines may suffer from bias in construction. They are labour intensive and costly, in both lag time and dollars, to update with changes in practice or to match local conditions. Once in place guidelines require constant maintenance to keep pace with clinical science, drug development and demographic variation of illness [18] . A simple literature search of the Pubmed database indicates 234 new CAP papers for the year 2000 alone [19] .

Guidelines generally lack the flexibility to deal with uncertain values in medicine. Taking a traditional statistical approach they divide patients into discrete categories, which may not truly represent the likelihood of certain outcomes. They contain hidden utility judgements of the value of medical outcomes. Once fixed in a guideline these judgements do not allow for situational variables such as patient preference [20] . The adoption of guidelines by practitioners is highly variable and dependent on characteristics of the physician, the patient and the medical system [21] .

References

1. Clark S, Pradhan M, Faunt J, Swart R. A comparison of a paper-based clinical guideline and a decision support system for the management of community acquired pneumonia. Health Informatics Society of Australia Conference Proceedings 2000.

2. Gilbert K, Gleason PP, Singer DE, Marrie TJ, Coley CM, Obrosky DS, et al. Variations in antimicrobial use and cost in more than 2,000 patients with community-acquired pneumonia. Am J Med 1998;104(1):17-27.

3. Fine MJ, Smith MA, Carson CA, Mutha SS, Sankey SS, Weissfeld LA, et al. Prognosis and outcomes of patients with community-acquired pneumonia. A meta-analysis [see comments]. Jama 1996;275(2):134-41.

4. Fine MJ, Stone RA, Singer DE, Coley CM, Marrie TJ, Lave JR, et al. Processes and outcomes of care for patients with community-acquired pneumonia: results from the Pneumonia Patient Outcomes Research Team (PORT) cohort study. Arch Intern Med 1999;159(9):970-80.

5. Hackner D, Tu G, Weingarten S, Mohsenifar Z. Guidelines in pulmonary medicine: a 25-year profile. Chest 1999;116(4):1046-62.

6. BTS Guidelines for the Management of Community Acquired Pneumonia in Adults. Thorax 2001;56 Suppl 4:IV1-64.

7. Niederman MS, Mandell LA, Anzueto A, Bass JB, Broughton WA, Campbell GD, et al. Guidelines for the management of adults with community-acquired pneumonia. Diagnosis, assessment of severity, antimicrobial therapy, and prevention. Am J Respir Crit Care Med 2001;163(7):1730-54.

8. Bartlett JG, Breiman RF, Mandell LA, File TM, Jr. Community-acquired pneumonia in adults: guidelines for management. The Infectious Diseases Society of America. Clin Infect Dis 1998;26(4):811-38.

9. Meehan TP, Fine MJ, Krumholz HM, Scinto JD, Galusha DH, Mockalis JT, et al. Quality of care, process, and outcomes in elderly patients with pneumonia [see comments]. Jama 1997;278(23):2080-4.

10. Dean NC, Silver MP, Bateman KA, James B, Hadlock CJ, Hale D. Decreased mortality after implementation of a treatment guideline for community-acquired pneumonia. Am J Med 2001;110(6):451-7.

11. Marrie TJ, Lau CY, Wheeler SL, Wong CJ, Vandervoort MK, Feagan BG. A controlled trial of a critical pathway for treatment of community-acquired pneumonia. CAPITAL Study Investigators. Community-Acquired Pneumonia Intervention Trial Assessing Levofloxacin [see comments]. Jama 2000;283(6):749-55.

12. Fine MJ, Pratt HM, Obrosky DS, Lave JR, McIntosh LJ, Singer DE, et al. Relation between length of hospital stay and costs of care for patients with community-acquired pneumonia [In Process Citation]. Am J Med 2000;109(5):378-85.

13. Dean NC, Suchyta MR, Bateman KA, Aronsky D, Hadlock CJ. Implementation of admission decision support for community-acquired pneumonia. Chest 2000;117(5):1368-77.

14. Weingarten SR, Riedinger MS, Hobson P, Noah MS, Johnson B, Giugliano G, et al. Evaluation of a pneumonia practice guideline in an interventional trial. Am J Respir Crit Care Med 1996;153(3):1110-5.

15. Rhew DC, Riedinger MS, Sandhu M, Bowers C, Greengold N, Weingarten SR. A prospective, multicenter study of a pneumonia practice guideline. Chest 1998;114(1):115-9.

16. Gleason PP, Kapoor WN, Stone RA, Lave JR, Obrosky DS, Schulz R, et al. Medical outcomes and antimicrobial costs with the use of the American Thoracic Society guidelines for outpatients with community-acquired pneumonia. Jama 1997;278(1):32-9.

17. Siegel RE. Community-Acquired Pneumonia in the 21st Century: Medscape.com, 2000.

18. Owens DK, Nease RF, Jr. A normative analytic framework for development of practice guidelines for specific clinical populations. Med Decis Making 1997;17(4):409-26.

19. NLM. Pubmed, 2000.

20. Protheroe J, Fahey T, Montgomery AA, Peters TJ. The impact of patients' preferences on the treatment of atrial fibrillation: observational study of patient based decision analysis [see comments]. Bmj 2000;320(7246):1380-4.

21. Halm EA, Atlas SJ, Borowsky LH, Benzer TI, Metlay JP, Chang YC, et al. Understanding physician adherence with a pneumonia practice guideline: effects of patient, system, and physician factors. Arch Intern Med 2000;160(1):98-104.