Introduction
The PROWESS [1] study reported the development of an apparently successful, but expensive, treatment for severe sepsis. All but two of the 26 adult, general intensive care units (ICUs) in Scotland participated in a prospective audit of admissions during 1999 and 2000. We reviewed our data to assess the extent and effect of sepsis, evident in the first day of intensive care, in this 2-year period.
Results
Almost 40% of all patients were septic within the first 24 hours of ICU admission, and 44% of these had severe sepsis (18% of all admissions). This proportion was consistent in both 1999 and 2000. The ICU mortality was 30% in the sepsis group and 50% in the severe sepsis group, compared to an overall Scottish ICU mortality of 21.5%. A further 9% die before hospital discharge. Although this attrition rate is similar to that in the general ICU population, it means that patients with severe sepsis are twice as likely to die before hospital discharge as the general ICU population. Patients with severe sepsis have higher APACHE II scores (mean 25) compared to those with sepsis (21) or the ICU population in general (19) and stay in ICU longer (mean increase 1.8 days, median 1.1). The standardised mortality ratio (SMR) of 1.16 in the severe sepsis group is clearly of concern, but is unlikely to be due to poor quality of care since the SMRs for Scottish ICUs are known to be in line with expectation [2].
Conclusion
Severe sepsis has important consequences for individual patients, ICU resources and community health. There is the potential for new therapies to make a significant impact on all of these but close surveillance on a national rather than selective basis will be required to assess the cost and benefit.
Table 1.
Summary of data collected during 1999 and 2000 in Scottish ICUs
| All admissions (n = 16,000) | Sepsis (n = 6504) | Severe sepsis (n = 2892) | ||
|---|---|---|---|---|
| LOS (days) | Median/mean | 1.8/4.53 | 2.2/5.26 | 2.9/6.3 |
| Age (years) | Mean | 58.3 | 57.9 | 61.4 |
| Mortality (%) | ICU/hospital | 21.5/29.9 | 29.6/38.6 | 50.4/58.7 |
| APACHE II | Probability (%) | 33.0 | 38.5 | 50.1 |
| SMR (95% CI) | 0.905 (0.884-0.927) | 0.990 (0.970-1.01) | 1.16 (1.12-1.19) |