Intraoperative administration of Hextend^® versus 6% Hetastrach in saline for the treatment of hypovolemia during major surgery: preliminary results of a randomized clinical trial

Introduction

Hextend^® is a new 6% hydroxyethyl starch (mean molecular weight 550 Kd) in a balanced and buffered electrolyte and glucose solution intended for use as a plasma expander. In animal models Hextend^® appears to offer significant advantages over currently available alternatives (e.g Hespan^®) in terms of acid/base/electrolyte/glucose balance and survival. Hextend can potentially serve as an economical, sterile, physiologically-balanced replacement for blood volume lost subsequent to trauma related bleeding. It may also be used to induce mild to moderate hypothermia in order to prolong survival time during transport to a critical care center. We report here the preliminary results of the on-going phase III study of Hextend^®.

Methods

Following Institutional Review Board approval and informed patient consent, patients undergoing major elective surgery were enrolled at The Mount Sinai Medical Center (NY, NY) and Duke University Medical Center (Durham, NC) in a prospective, randomized, blinded clinical trial. Lactated ringers crystalloid was used as a maintenance fluid intraoperatively as follows: 7 ml/kg prior to induction of general anesthesia followed by an infusion of 5 ml/kg/h. Intraoperative hypovolemia was treated with 250 ml doses of either Hextend^® or 6% hetastarch in saline. Where appropriate data (unaudited) are presented as median, mean ± SD, and range.

Results

Data from 117 patients are presented. Procedure types were major urologic (37.6%), major general (42.7%), major gynecologic (17.9%), and major orthopedic (1.7%). Postoperative length of stay (days) was 6, 7 ± 5,1–34. Duration of anesthesia (minutes) was 307, 315 ± 126, 90–780. Estimated blood loss (ml) was 800, 1161 ± 1331, 20–7300. The amount of study fluid administered (6% hetastarch of either type) was 1250, 1510 ± 1016, 0–5000. 38.5% of patients received the study fluid in excess of 20 ml/kg. No serious and unexpected adverse events related to the study fluid were observed in the study cohort.

Conclusions

Hextend^® is a novel plasma volume expander presented in a balanced and buffered electrolyte and glucose solution. Data analysis and unblinding from this clinical trial will be completed soon and will be presented at this conference.