Figure 2.

a) To minimize the mechanical volume between the flow constrictor and the valve, the solenoid-actuated valves of the oxygen and nitrogen lines use a constrictor integrated into the brass hose barb, highlighted by the black oval background. b) Similarly, the flow constrictor for hyperpolarized gas (emphasized by the black oval background) is located as close as possible to the Teflon-constructed, pneumatically-actuated valve. c) The volume from the tip of the endotracheal tube (left) to the junction tee of the inhale and exhale line is limited to 0.02ml as indicated by the black background