Case Study

Copolyester Material Meets the Needs of Three-Port Anesthesia Manifold

The clear, lipid-resistant material can be molded to tight tolerances.

To better control the spread of infectious diseases and maximize the safety of healthcare providers, anesthesiologists are actively seeking alternatives to the use of needles during surgery. One system that has found widespread acceptance is the CheckMate anesthesia system from Quest Medical Inc. (Allen, TX.)

The heart of the system is a three-port manifold molded of Eastar PCTG copolyester from Eastman Chemical Co. (Kingsport, TN). While permitting delivery of several medications at once, its unique design provides minimal residual volume, or "dead space," permitting quick, direct injection of anesthetic into the fluid path. This assures delivery of an accurate, cost-efficient dose without flushing.

Each port contains a small plastic disc, sealed by sonic welding, through which a syringe or other delivery device can be inserted. All CheckMate anesthesia sets have an in-line, one-way check valve that prevents retrograde flow and directs the anesthetic toward the patient. Open check valves are used for gravity infusions, while pressure activated valves are designed for use with pumps and syringes.

"This part was designed from the very beginning to be molded of Eastar," says David Roosth, director of materials for Quest Medical. "We needed a clear, lipid-resistant material that could be molded to very tight tolerances. We also needed a material that could withstand sonic welding and solvent bonding without cracking and crazing."

Another important consideration, according to Roosth, was sterility. Eastar PCTG copolyester can be sterilized with either gamma radiation or EtO without clouding or weakening. And because it is latex-free, it alleviates concerns about latex allergy on the part of patients and healthcare workers.

"The people at Eastman were very helpful when we were first considering this design," notes Roosth. "They provided advice and suggestions on the design and the tooling. They even helped us select a molder for the part."

The part is molded by Courtesy Med/Tek (Chicago). "We worked closely with Eastman in developing this application," says Mike Cullen, a Courtesy Sales Engineer. "We felt from the beginning that Eastar PCTG copolyester was the best material for the job, but we also test-molded acrylic and polycarbonate. We found no improvement in moldability, and Eastar was better able to withstand sonic welding."

For more information:

Quest Medical Inc., One Allentown Pky., Allen, TX 75002. Tel: 972-390-9800; Fax: 972-390-2881.

Courtesy Med/Tek, 1019 Noel, Chicago, IL 60090. Tel: 847-541-7900; Fax: 847-215-0350.

Eastman Chemical Co., P.O. Box 431, Kingsport, TN 37662. Tel: 423-229-1424; Fax: 423-229-8595.