PISA: the prevalence of infection in intensive care units in South Africa

Introduction

Sepsis in the ICU is a major cause of morbidity and mortality. In addition it increases the direct and indirect cost of care. Effective intervention to improve patient outcome and ensure optimal use of resources depends on the availability of data. No epidemiological data are available on the prevalence of sepsis in South Africa. This study was a 1-day sepsis prevalence study conducted in an attempt to address this lack of data.

Method

Following appropriate institutional approval, 43 ICUs were selected using the proportional probability sampling technique. This was applied to a national database of ICUs. Every seventh bed was selected from all the serially placed units. Data collected identified the profile of the unit and the patient details for the day in question (15 August 2005). The primary endpoint was a peer-reviewed determination of the need for antibiotic prescription as determined by two independent reviewers. Sepsis was defined according to the ACCP/SCCM criteria. Secondary end-points included determination of diagnostic ability of attending clinicians, antibiotic prescribing patterns and appropriateness of modification of therapy based on microbiological data.

Results

The mean age of patients was 55 years (n = 248) with a male:female ratio of 60:40. Sixty-eight per cent of patients were admitted post surgery. There was reasonable concordance for sepsis, severe sepsis and septic shock (Table 1). A total of 196/248 (79%) patients were deemed to require antibiotics by the attending clinician, compared with 69/248 (28%) who were deemed to have sepsis by independent review. Fifty-one per cent of patients were inappropriately diagnosed as having sepsis. The commonest site of sepsis (as determined by the assessors) was the lung (45%) followed by the abdomen (10%). In 42% of cases antimicrobial prescription was adjudged as being appropriate, while in 11% of cases antimicrobials were appropriately modified following microbiology results. The duration of therapy was appropriate in 26% of cases.

Table 1 Diagnostic concordance

Conclusion

The national prevalence of sepsis, the site of sepsis and the patient profile in South Africa is similar to that described in other studies [1]. Treating doctors are reasonably accurate in diagnosing sepsis but prescribe antiobiotics inappropriately in the vast majority of cases.