It seems that Hydroxyethyl, Hetastarch or HES has been referred to by the WT in the 'public' publications (as per the WT CD-Rom) around eight times, from 1977 (first) through to 2000 (last)
Jehovah’s Witnesses and the Question of Blood 1977, page 54, paragraph 152
Another approach is to replace lost blood with colloids such as dextran. That is a clinical sugar solution that has proved valuable both in surgery and in treating burn cases and shock . Sometimes it is combined with a buffered salt solution so as to draw on the best properties of each. Haemaccel and hydroxyethyl starch solution have also been employed with good results in various operative situations as plasma volume expanders .
Footnote 94. Surgical Clinics of North America, June 1975, p. 671.
Surgical Clinics of North America, Volume 55, Issue 3, June 1975, Pages 659-678
Hemodilution / Konrad Messmer M.D.
Awake 22 February 1980, pages 21 to 23
Artificial Blood” Makes Its Debut
Despite its complexity, scientists have been working to copy human blood, or at least to produce a replacement that can temporarily assume some of the functions of the real thing. Examples of such products now in use are dextran, Haemaccel, hydroxyethyl starch, Ringer’s lactate, and common saline solution. However, such solutions can take over only a few functions of blood, and serve primarily as volume expanders. As such, they fill out the blood-vessel system after blood loss, thus preventing sludging of blood cells, until the body itself replaces what is missing.
Awake 22 June 1982, pages 26 and 27
Jehovah’s Witnesses — The Surgical/Ethical Challenge
(This was a reprint from The Journal of the American Medical Association (JAMA), November 27, 1981, Volume 246, No. 21, pages 2471, 2472)
Current and future applications of hetastarch , large-dose intravenous iron dextran injections [5,6], and the "sonic scalpel"  are promising and not religiously objectionable.
Footnote 4: 4 Hetastarch (Hespan)—a new plasma expander. The Medical Letter on Drugs and Therapeutics 1981;23:16
How Can Blood Save Your Life? 1990, page 14
Quality Alternatives to Transfusion
Volume replacement can be accomplished without using whole blood or blood plasma. Various nonblood fluids are effective volume expanders. The simplest is saline (salt) solution, which is both inexpensive and compatible with our blood. There are also fluids with special properties, such as dextran, Haemaccel, and lactated Ringer’s solution. Hetastarch (HES) is a newer volume expander, and "it can be safely recommended for those [burn] patients who object to blood products." (Journal of Burn Care & Rehabilitation, January/February 1989) Such fluids have definite advantages. "Crystalloid solutions [such as normal saline and lactated Ringer’s solution], Dextran and HES are relatively nontoxic and inexpensive, readily available, can be stored at room temperature, require no compatibility testing and are free of the risk of transfusion-transmitted disease." — Blood Transfusion Therapy — A Physician’s Handbook, 1989.
Journal of Burn Care & Rehabilitation, January/February 1989
Hetastarch: An Alternative Colloid in Burn Shock Management.
Waters, L. M. MD, FRCS(C); Christensen, M. A. RN, CCRN; Sato, R. M. MD
Blood Transfusion Therapy — A Physician’s Handbook, 1989 (3rd Edition)
American Association of Blood Banks
How Can Blood Save Your Life? 1990, pages 27 to 29
Appendix: Jehovah’s Witnesses — The Surgical/Ethical Challenge
Reprint from JAMA as per 1982 Awake above
Watchtower 1 June 1990, pages 30 and 31
Questions From Readers: Do Jehovah’s Witnesses accept injections of a blood fraction, such as immune globulin or albumin?
A pregnant woman has an active mechanism by which some immune globulin moves from the mother’s blood to the fetus’. Because this natural movement of antibodies into the fetus occurs in all pregnancies, babies are born with a degree of normal protective immunity to certain infections.
It is similar with albumin, which doctors may prescribe as a treatment for shock or certain other conditions . Researchers have proved that albumin from the plasma is also transported, though less efficiently, across the placenta from a mother into her fetus.
Footnote 3: Evidence shows that nonblood volume replacement fluids (such as hetastarch [HES]) can be used effectively to treat shock and other conditions for which an albumin solution might have been used previously.
Awake 22 November 1991, pages 8 to 11
Pioneering Bloodless Surgery With Jehovah’s Witnesses
[Box on page 10] Preventing and Controlling Hemorrhage Without Blood Transfusion
5. Volume Expanders:
(1) Ringer’s lactate (Eichner, E. R., Surgery Annual, January 1982, pages 85-99)
(2) Normal saline
(2) Gelatin (Howell, P. J., Anaesthesia, January 1987, pages 44-8)
Awake 8 January 2000, pages 7 to 11
The Growing Demand for Bloodless Medicine and Surgery
[Box] Bloodless Medicine and Surgery
Some of the Methods
Fluids: Ringer’s lactate solution, dextran, hydroxyethyl starch, and others are used to maintain blood volume, preventing hypovolemic shock. Some fluids now being tested can transport oxygen.