Estimate of the Number of Patients Eligible for Treatment with Drotrecogin Alfa (Activated) Based on Differing International Indications: Post-hoc Analysis of an Inception Cohort Study in Australia and New Zealand

Reliability and accuracy of practitioner-calculated Acute Physiology and Chronic Health Evaluation II scores for determining the appropriateness of drotrecogin alfa (activated)

PURPOSE

The reliability and accuracy of practitioner-calculated Acute Physiology and Chronic Health Evaluation (APACHE) II scores for determining the appropriateness of drotrecogin alfa (activated) in critically ill patients were evaluated.

METHODS

Three adjudicated clinical cases of sepsis were developed using composites of real patient scenarios. The patients' APACHE II scores were independently assessed by randomly selected critical care practitioners (physicians and nonphysicians). Each case contained at least one reason to consider withholding drotrecogin alfa (activated), but none had a definitive contraindication to drotrecogin alfa (activated). Intraobserver and interobserver variabilities were assessed using kappa correlation. Accuracy was assessed by comparing median scores to the adjudicated scores and evaluating correctly classified APACHE II scores.

RESULTS

A total of 21 (42%) physicians and 14 (56%) nonphysicians completed all assessments. Intraobserver and interobserver variabilities were 0.16 and 0.49 for the total APACHE II score, respectively. Median calculated APACHE II scores significantly differed for case 1 (p = 0.003) and case 3 (p < 0.0001). The percentage of error in calculating the total APACHE II score approached 85%. The main reasons for administering drotrecogin alfa (activated) were an APACHE II score of >or=25 and multiple organ failures. The main reason for therapy was a high bleeding risk or an APACHE II score of <25.

CONCLUSION

Weak intraobserver agreement, modest interobserver reliability, a high error rate, and low accuracy limited the clinical application of the APACHE II score by untrained practitioners, indicating that the APACHE II score should not be the only determinant for the use of drotrecogin alfa (activated).