– 40 –
NOTE:
When connecting to the PENTAX endoscope, connect only the medical
grade regulated source of gas which pressure can be controlled.
2) The gas adapter, which can be secured to the air/water port on the PVE connector,
has a luer receptacle to accept tubing from an external source of nonflammable
gas. As long as the air/water feeding tube from a PENTAX water bottle assembly
is connected to the gas adapter and the air pump in the video processor is turned
OFF, nonflammable gas can be delivered.
NOTE:
Set the pressure below 49kPa (7.1psi) and the flow rate at about 4 liters/
min.
CAUTION:
Open the valve of the CO
2
gas cylinder only AFTER turning off the pump
switch of the video processor. Failure to do so will apply excessive pressure
to the video processor and can cause damage to the air pump.
3) Flow of gas from the nozzle at the distal end of the endoscope can be checked
by placing the tip of the endoscope under water and covering the hole on the top
of the air/water feeding valve. The flow rate of gas should be no greater than the
rate of air delivery when the air/water feeding valve on the control head of the
endoscope is covered.
4) The water delivery system is activated by pressing the air/water feeding valve.
5) The operator and assistant(s) should wear surgical gloves to avoid burns during use
of laser equipment.
CAUTION:
It should be noted that as long as the valve of the CO
2
gas cylinder is
OPEN and the hole at the top of the A/W feeding valve is NOT covered,
CO
2
gas will constantly be vented through the A/W valve into the room.
To reduce excessive CO
2
concentrations, it is, therefore, recommended to
close the CO
2
gas cylinder valve, work in a well ventilated room, and use
air delivery whenever possible during examinations which are lengthy or in
very confined quarters.
As an alternative, the optionally available gas/water feeding valve, model
OF-B194, may be used in place of the standard air/water feeding valve.
OF-B194 is a closed two-stage valve mechanism. Pressing the first stage
delivers CO
2
gas and depressing the second stage activates water delivery.
NOTE:
When using the OF-B194 valve, there will be no venting of CO
2
gas into
the room. Place OF-B194 with the air/water feeding valve OF-B188 after
using the CO
2
gas.