Architecture, implementation, and testing of a multiple-shell gas injection system for high current implosions on the Z accelerator.

Tests are ongoing to conduct ~20 MA z-pinch implosions on the Z accelerator at Sandia National Laboratory using Ar, Kr, and D2 gas puffs as the imploding loads. The relatively high cost of operations on a machine of this scale imposes stringent requirements on the functionality, reliability, and safety of gas puff hardware. Here we describe the development of a prototype gas puff system including the multiple-shell nozzles, electromagnetic drivers for each nozzle's valve, a UV pre-ionizer, and an inductive isolator to isolate the ~2.

Arterial misplacement of large-caliber cannulas during jugular vein catheterization: case for surgical management.

Background: Accidental placement of a large sheath or catheter in an artery during central venous cannulation, though rare, is a potentially devastating complication. The present study reviews our 14-year experience with this complication to determine appropriate role of surgical management.

Study Design: Review was conducted of all cases involving patients treated by the vascular surgery service from July 1989 to June 2003 for accidental placement of a large-caliber cannula (>or= 7 F) in an artery during catheterization of the jugular vein.