Are shock index and adjusted shock index useful in predicting mortality and length of stay in community-acquired pneumonia?

BACKGROUND: Community Acquired Pneumonia (CAP) is a common infection which is associated with a significant mortality. Shock index, heart rate divided by blood pressure, has been shown to predict mortality in several conditions including sepsis, acute myocardial infarction and traumatic injuries. Very little is known about the prognostic value of shock index in community acquired pneumonia (CAP). OBJECTIVE: To examine the usefulness of shock index (SI) and adjusted shock index (corrected to temperature) (ASI) in predicting mortality and hospital length of stay in patients admitted to hospital with CAP. METHODS: A prospective study was conducted in three hospitals in Norfolk & Suffolk, UK. We compared risk of mortality and longer length of stay for low (=<1.0, i.e. heart rate =< systolic BP) and high (>1.0, i.e. heart rate > systolic BP) SI and ASI adjusting for age, sex and other parameters which have been shown to be associated with mortality in CAP. RESULTS: A total of 190 patients were included (males=53%). The age range was 18-101 years (median=76 years). Patients with SI & ASI >1.0 had higher likelihood of dying within 6 weeks from admission. The adjusted odds ratio for 30 days mortality were 2.48 (1.04-5.92; p=0.04) for SI and 3.16 (1.12-8.95; p=0.03) for ASI. There was no evidence to suggest that they predict longer length of stay. CONCLUSION: Both SI and ASI of >1.0 predict 6 weeks mortality but not longer length of stay in CAP.

Confusion, Urea, Respiratory Rate and Shock Index or Adjusted Shock Index (CURSI or CURASI) criteria predict mortality in community-acquired pneumonia.

BACKGROUND: Community-acquired pneumonia (CAP) is common and associated with a significant mortality. Shock index, heart rate divided by systolic blood pressure, has been shown to be associated with outcome in sepsis. OBJECTIVE: To examine the usefulness of two new criteria CURSI (confusion, urea, respiratory rate and shock index), and CURASI where shock index is replaced by temperature adjusted shock index in mortality assessment of CAP. METHODS: A prospective study was conducted in Norfolk and Suffolk, UK. We explored the usefulness of CURSI and CURASI which we derived and performed mapping exercise using a different cohort. In this study we compared these new indices with the CURB-65 criteria in correctly predicting mortality in CAP. RESULTS: A total of 190 patients were included (males=53%). The age range was 18-101 years (median=76 years). There were a total of 54 deaths during a six-week follow-up. All died within 30-days. Sixty-five (34%) had severe pneumonia by CURB-65. Using CURSI and CURASI, 71(37%) and 69(36%) had severe pneumonia, respectively. The sensitivity, specificity, positive and negative predictive values in predicting death during six-week follow-up were comparable among three indices examined. The Receiver Operating Characteristic curve values (95%CI) for the criteria were 0.67(0.60-0.75) for CURB-65, 0.67(0.59-0.74) for CURSI and 0.66(0.58-0.74) for CURASI (p>0.05). There were strong agreements between these three indices (Kappa values > or =0.75 for all). Repeating analyses in those who were aged 65years and over (n=135) did not alter the results. CONCLUSIONS: Both CURSI and CURASI are similarly useful to CURB-65 in predicting deaths associated with CAP including older patients.