IMPORTANT CHANGES TO 2001 BTS GUIDELINES ON CAP MANAGEMENT

Microbiological investigation

Several studies have provided further evidence that the overall sensitivity of blood and sputum cultures in CAP is low, particularly for patients with non-severe CAP and no co-morbid disease and for those who have received antibiotic treatment before admission.^2–5 This has led to a changed recommendation that blood cultures may be omitted in a patient with no severity indicators or co-morbid disease providing the diagnosis of CAP has been definitely confirmed. The latter condition is important, particularly when dealing with a febrile patient where the site of infection is not clear and blood cultures can be very useful. The value of rapid legionella urine antigen testing was clearly demonstrated in a large outbreak of Legionnaires’ disease in Holland, which found that early antibiotic management of patients could be guided by the results of rapid testing, resulting in improved outcome both in mortality and need for intensive care.⁶ Outside the epidemic situation there is also evidence that early detection of urine legionella antigen can positively influence management of sporadic cases of legionella pneumonia.⁷ This is an important message as there is growing evidence that delays in appropriate antibiotics adversely affect the outcome of pneumonia, particularly with legionella infection. Similarly, pneumococcal urine antigen tests have reported significantly greater sensitivity rates than routine blood or sputum cultures.^8,9 Both legionella and pneumococcal urine antigen testing are recommended for severe pneumonia, together with a rapid reporting service for legionella urine antigen for all hospitals admitting patients with CAP.

Severity assessment

Severity assessment remains the key to deciding the site of care (whether at home, in a medical ward, or critical care ward) and guiding both general management and antibiotic treatment. The severity assessment tool recommended in the 2001 BTS CAP guidelines¹ was an amalgamation of aspects of the Fine pneumonia severity index (PSI),¹⁰ the modified BTS severity criteria described in the 1993 BTS CAP guidelines,¹¹ and other adverse prognostic features published in the literature, and resulted in a rather cumbersome and non-memorable two step assessment process based on core, additional, and pre-existing adverse prognostic features. A recently published international study¹² derived and tested a simpler severity assessment tool, the CURB-65 score, with a six point scale (0–5)—one point for each of Confusion, Urea >7 mmol/l, Respiratory rate ⩾30/min, low systolic (<90 mm Hg) or diastolic (⩽60 mm Hg) Blood pressure, and age ⩾65 years—based on information available at the initial hospital assessment. Patients could be stratified into three groups according to increasing risk of mortality, hence adding support to clinical judgement regarding the need for hospital admission or intensive care management. Patients with a CURB-65 score of 3 or more are at high risk of death and should be managed as having severe pneumonia, those with a score of 2 are at some increased of risk of death and should be considered for short stay inpatient treatment or hospital supervised outpatient treatment, and those with a score of 0 or 1 are at low risk of death and may be suitable for home treatment. Both the BTS Pneumonia Guidelines Committee and the BTS Standards of Care Committee recommended adopting this revised severity assessment tool for the 2004 CAP update because of the more robust evidence, a single step assessment (compared with the current two step model), and a simpler algorithm to remember. Further prospective studies are needed to assess the true value of this newly adopted assessment tool, both in hospital and also in the community where a similarly predictive tool omitting the blood urea result (the CRB-65 score) can also be simply calculated.

Use of non-invasive ventilation

Non-invasive ventilation (NIV) plays a key role in the management of ventilatory failure in patients with chronic obstructive pulmonary disease, and several studies have reported that provision of NIV in patients with severe CAP can lead to initial improvement.^13–15 However, as over half of these patients later deteriorate and require intubation, this has led to the recommendation that, for CAP, trials of NIV should only occur in an appropriate critical care setting.¹⁶

Discharge planning

A recent North American prospective multicentre study¹⁷ identified clinical factors that were useful in deciding whether a patient with CAP was sufficiently stable to be discharged from hospital. The presence of two or more features of clinical instability (based on temperature, heart rate, respiratory rate, blood pressure, oxygen saturation, mental status, and oral intake) predicted a significant chance of re-admission or mortality. It is recommended that this assessment is considered when planning for discharge.

Antibiotics

Moxifloxacin has joined levofloxacin as the only licensed newer fluoroquinolones recommended for CAP in the UK, although the use of moxifloxacin is limited as it is not licensed for use in severe pneumonia, nor is it available in a parenteral formulation in the UK. As before, new fluoroquinolones are not recommended as first line agents or for community use for pneumonia, but can provide a useful alternative in selected hospitalised patients with CAP.^18,19

FUTURE PRESENTATION OF GUIDELINE UPDATES

Like the 2001 guidelines, the update does not cover economic or quality assessment of CAP care—an area which is becoming increasingly important for audit and clinical governance²⁰ and will probably need to be included in future updates.

One challenge has been how to present updates of BTS guidelines. Various models are possible. In December the Infectious Diseases Society of America published the 2003 update of their 2000 guidelines on the management of CAP as a stand alone article on both their website and in Clinical Infectious Diseases²¹—a table summarising both the recommendations of 2000 and also the new recommendations for 2003 (printed in bold). For this update the BTS is using a web based article linked to a pdf document of the full 2001 guidelines available from the BTS website. It is expected that readers will download and view both documents together, but feedback will be welcome to guide the BTS in the best way of presenting future updates for its numerous published clinical guidelines. Ultimately, dissemination of the guideline will require respiratory physicians to inform and educate their colleagues, both in hospital and primary care. It is hoped that these few important recommendations will be incorporated easily into clinical practice.