Hydroxyethyl Starch on Kidney and Haemostatic Function in Cardiac Surgical Patients: Is A Non-Inferiority Study Design Appropriate for This Setting?

We read with great interest the paper by Duncan et al. on the effect of hydroxyethyl starch (HES) on kidney and haemostatic function in cardiac surgical patients [1]. In their single‐centre, triple‐blind, parallel group, randomised ‘non inferiority’ trial, the authors tested the primary hypothesis that kidney function was not worse in cardiac surgery patients who received HES compared with patients assigned to receive albumin. The authors concluded that reported evidence proves “lack of harm” due to similar results between the groups.

In light of the existing concerns on HES use, this study leaves several unanswered questions: how should patients be informed when they are asked to participate in a clinical trial that may randomise them to receive HES? How can a prestigious research group consider it appropriate to adopt a ’non‐inferiority’ study design to evaluate the safety profile of a controversial drug such as HES, when any proven beneficial effects (if there are any) remain unanswered?