Sepsis incidence and mortality are underestimated in Australian intensive care unit administrative data

TO THE EDITOR: We commend Heldens and colleagues1 for publishing their data on the incidence and in‐hospital mortality of sepsis and septic shock among patients admitted to Australian intensive care units (ICUs). The incidence of sepsis and septic shock in ICUs is estimated to be 101.8 and 19.3 per 100 000 patient‐years, respectively, at an attributable cost of $32 421.2 We concur that sepsis cases captured using the Australian and New Zealand Intensive Care Society Centre for Outcome and Resource Evaluation database criteria, compared with prospective clinical diagnoses,3 has poor sensitivity for sepsis case ascertainment.

Notwithstanding, we propose that the application of a third surveillance metric using coded discharge data could be a viable alternative for sepsis case ascertainment and monitoring in ICUs. International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification (ICD‐10‐AM) diagnostic coding data are feasible to collect with a reduced risk of sampling bias and minimal loss to follow‐up.

Using tandem dataset comparison following the implementation of a hospital‐wide sepsis pathway,4 we explored the utility of coding data for sepsis surveillance. We noted that 78% and 74% of ICU cases were designated an ICD‐10‐AM code denoting sepsis at admission and patient level, respectively (Box). Alarmingly, the concordance rate between coded administrative data and clinically verified sepsis diagnoses was even lower in non‐ICU settings. These data are in keeping with international reports.2

Robust and reproducible data are required to evaluate quality improvement regarding sepsis management. Given the poor sensitivity of research criteria and coding data, used in isolation for sepsis identification, a multifaceted approach is required. We hypothesise that the combination of administrative coding data and electronic medical record data, augmented with sepsis screening algorithms, may improve the sensitivity for sepsis case ascertainment in both cancer and non‐cancer settings.5 We encourage Heldens and colleagues to consider these suggestions as an alternative reproducible method needed to elucidate the incidence of sepsis and septic shock in Australian ICUs.