Efficacy comparison of ramosetron with ondansetron on preventing nausea and vomiting in high-risk patients following spine surgery with a single bolus of dexamethasone as an adjunct.

BACKGROUND: Despite the development of a new class of antiemetics, postoperative nausea and vomiting (PONV) still remains a frequent and distressing complication. We compared the prophylactic antiemetic effect of administering dexamethasone 5 mg as an adjunct to ramosetron and ondansetron in patients at high-risk for PONV following lumbar spinal surgery. METHODS: In this randomized, double-blind study, 120 female non-smoking patients with intravenous patient-controlled analgesia (PCA) received ramosetron 0.3 mg plus dexamethasone 5 mg (group R + D) or ondansetron 4 mg plus dexamethasone 5 mg (group O + D) intravenously. Fentanyl-based PCA was administered for 48 hr postoperatively; ramosetron 0.3 mg or ondansetron 12 mg was added to the PCA regimen according to the allocated group. The incidence of PONV and rescue antiemetic were assessed for 48 hr postoperatively at 0-6, 6-24, and 24-48 hr. RESULTS: The overall incidence of PONV did not differ between the groups (50% vs. 60%, in groups R + D and O + D, respectively). The overall incidence of nausea was similar between groups (47% vs. 60%, in groups R + D and O + D, respectively). The overall frequency of vomiting was also similar between groups (8% vs. 12%, in groups R + D and O + D, respectively). The severity of nausea and the overall use of rescue antiemetic were not different between groups. CONCLUSIONS: The antiemetic efficacy of ramosetron plus dexamethasone was similar to that of ondansetron plus dexamethasone on preventing PONV in high-risk patients undergoing lumbar spinal surgery.

Fabrication of thermally stable and cost-effective polymeric waveguide for optical printed-circuit board.

A thermally stable polymeric optical waveguide has been fabricated using ultraviolet (UV)-curable epoxy resins for the core and clad materials. A simple and cost-effective fabrication method that uses reusable polydimethylsiloxane (PDMS) masters has been developed. The 12-channel under-clad layer of the UV-cured epoxy was prepared using a PDMS master whose embossed channels had been fabricated by a polycarbonate (PC) secondary master. The thermal stability of the fabricated waveguide was tested at 200 degrees C for one hour. The optical waveguide was not damaged physically by thermal stress. Propagation losses detected by a cut-back method were 0.16 dB/cm and 0.26 dB/cm, respectively, before and after the thermal stability test at 850 nm. Loss increase after the thermal treatment can be attributed to the formation of the absorbing and scattering sources. This waveguide can be applied for areas that require thermal stability such as an optical printed-circuit board.

Experimental demonstration of 10 Gbit/s transmission with an optical backplane system using optical slots.

A practical optical backplane system was prepared with transmitter-receiver processing boards and an optical backplane made from polymeric-waveguide-embedded optical printed-circuit boards. Optical slots were used as connection components between the transmitter-receiver processing boards and the backplane board to permit easy and repeatable insertion and extraction of the boards with micrometer precision. We report 10 Gbit/s data transmission between an optical backplane and the transmitter-receiver processing boards.