Use of deferred proxy consent in two emergency critical care trials

Introduction

Almost all patients with life-threatening conditions are incapacitated to give informed consent for participation in emergency critical care research. Deferred proxy consent (DPC) is an ethically valid surrogate for informed patient consent. Here we present our experience in two emergency trials [1].

Methods

We analysed the use of DPC in the Early Lactate-directed Therapy in Intensive Care Trial (NCT 00270673) and the NGAL study (TC 1405).

Results

In the lactate-directed therapy trial, 362 patients were randomized. In 75.4% DPC could be obtained, 3.9% of the relatives refused DPC and in 20.7% DPC could not be obtained before the end of the study (= 72 hours). In the NGAL study, 550 patients were randomized. DPC or patient consent was obtained in 89.8%, 0.7% refused DPC and in 9.4% DPC could not be obtained due to early patient death. In both studies combined, only in 2% was DPC refused and in 10% consent could not be obtained due to early patient death.

Conclusion

DPC is an ethically valid and practically feasible way to include patients in emergency critical care trials.