Operate the Prototype

How to set up, configure, operate, and troubleshoot the Prototype version of the field ventilator.

NOTE: These instructions are designed to show the steps common to all Modes, as well as the differences for 1:1 I/E Mode, 1:2 I/E Mode, and CPAP Mode.

Separate the two boxes

Slide the vertical slide latch in the center face of the upper box up and while holding it, slide the entire upper box forward (toward you), detaching it from the lower box.

Unpack the equipment for the Mode you are configuring

For maximum flexibility, take out all components for all Modes. The most flexible configuration is Mode 1:2, as it fairly easy to convert to Mode 1:1 or to Mode CPAP.

Carefully set the upper box aside to access the parts in the lower box. You need:

  • Patient ventilator manifold with one normally open (brass colored) solenoid
  • Patient ventilator manifold with one normally closed (silver colored) solenoid
  • Air supply tubing and brass tee fitting
  • Electrical cords to connect the manifold solenoids to the upper box power
  • Two patient ventilator manifolds with normally open (brass colored) solenoids
  • One patient ventilator manifold with normally closed (silver colored) solenoid
  • Tubing bridge with a normally closed (silver colored) solenoid
  • Air supply tubing (you will need two brass tee fittings for this configuration)
  • Electrical cords to connect the manifold solenoids to the upper box power
  • Two patient ventilator manifolds with normally open (brass colored) solenoid
  • Air supply tubing
  • This mode does not require timers or solenoids. Flow is continuous to the patient manifolds through normally open valves.

Emergency procedures and fail safe videos

Unpack the secondary (emergency) pump and its connected power and air attachments.

Set them aside near the ventilator in case the pump needs to be used in an emergency. It can be switched out with the primary pump in 20 seconds.

If you are in 1:1 I/E mode, you have extra “normally open” (brass colored) and “normally closed” (silver colored) solenoid valves. Keep them handy in case they need to be used in an emergency.

If you will only need 1:1 I/E respiratory support, you have extra “normally open” (brass colored) and “normally closed” (silver colored) solenoid valves. Keep them handy in case they need to be used in an emergency. During the emergency, manual flow control will be necessary. Here is how to manually control air flow to the patients while someone changes the defective solenoid valve. Watch the video.

If the pump fails, it can be replaced in 20 seconds. Watch this video.

The fail safe mode is bag valve masks operated manually per patient. The tradeoff you are making here is 1:2 I/E ratio and the ability to provide respiratory support for additional patients. There is no fail safe for solenoid failure when operating in 1:2 I/E Mode. If the pump fails in 1:2 I/E Mode, you can replace it in 20 seconds. Watch this video.

If the pump fails in CPAP Mode, you can replace it in 20 seconds. Watch this video.

Note: No solenoid valve switching is done in CPAP Mode.

Reconnect the boxes

Close the bottom box lid. Latch it and replace the upper box on the lower, locking it into place.

Connecting the tubing and electrical

The tubing and electrical connection instructions vary per Mode:

1:1 Mode only requires two solenoids, which are connected to the round plug. Plug the power to the solenoid valves into the plug on the face of the upper box. DO NOT PLUG THIS INTO AC POWER! Plug the air supply tubing firmly into the front nozzle on the air pump. There should be a Tee in the pump’s air supply and tubing to one normally open patient manifold and one normally closed patient manifold. Be sure you are using the solenoids that are connected to this electrical plug.
Connect main supply hose to the output nozzle of the pump.

Connect the brass tee fitting to the end of that hose.

To one side of the tee, run tubing to a patient manifold with normally open (brass colored) valves. Use the manifold that has an electrical supply wire connected to the large round plug.

To the other side of the Tee, run tubing to a patient manifold with normally closed (silver) solenoid valve (which is NOT attached to a patient manifold).

Be sure to connect this so that flow though the valve from the pump to the patient is in the direction of the arrow on the valve body.

Now connect tubing from the downstream side of that solenoid valve to a second brass tee.

To one side of THAT tee, connect a patient manifold with normally opened (brass colored) solenoid. Use the manifold which has an electric wire with the smaller plug attached to it.

To the other side of the tee, connect tubing to a patient manifold with a normally closed solenoid valve. Again, use the manifold with the wire connected to the smaller plug. This is the only patient manifold with a normally closed (silver) solenoid valve.

Plug in all electrical plugs on the front of the ventilator enclosure. WHEN YOU LATER UNPLUG THEM, BE CAREFUL NOT TO PULL BY THE WIRES. ALWAYS UNPLUG USING THE PLUG ITSELF.

Connect the tubing to the front of the pump and a brass Tee.

To both sides of the tee, run tubing to a patient manifold with a brass colored (normally OPEN) solenoid valve.

You do not need to open and close valves in CPAP mode so either don’t connect the power or turn off the timers.

Power the unit

Plug the ventilator unit’s rear AC power cord into 110V AC Power. The entire unit will draw less than 350 Watts of power.

The prototype unit uses an older model 12V DC power supply to the digital relay timers. It has an on-off switch on the face of it. Future units will likely not have a power switch on this power supply. So for the prototype model, make sure the power switch on the face of the large black box at the base on the left side is UP (on). This is supplying power to the digital relay timer in the upper center of the face of the ventilator unit.

Make sure that the Cooling fans (left and right) are plugged into the 5V DC power supply in the power strip.

Make sure there are three 110V AC plugs all plugged into the power strip (as well as the two USB plugs).

Open all patient ventilation ports on both manifolds fully—these have blue knobs.

The patient ventilation ports have smooth brass ends where standard elastic cuff 22mm breathing tube supply lines will attach.

The “Flow Control” valves on the free ends of the patient manifolds are for regulating flow out of the patient ventilation ports. You will adjust these only as needed when adding/removing a patient to/from a ventilation port

Do not adjust the control valve through the solenoids except in case of solenoid valve failure during Mode 1:1 operation. (see Fail Safe procedure info below). Note: There is no mechanical fail safe mode available for Mode 1:2 in the event of a timer or solenoid failure. Bag valve masks will be needed to provide rescue ventilation in such a case. For MODE CPAP, digital relay timers and solenoids are not used. Therefore, there is no risk of their failure. Just be certain you are using normally open solenoid valves to the patient manifolds in CPAP mode and that they are not being closed by the timer (timer needs to be off or valves disconnected from electrical supply).

Turn the ventilator on by switching power to the power strip on. It is located under the pump’s inlet tubing near the back of the enclosure.

Position the patient air manifolds where they will not be tripped on or interfered with.

Each time you add a patient ventilator line to the air manifold, test the flow in the line. Adding/removing patients may change flow in other lines. IT IS MOST IDEAL IF ALL PATIENTS ATTACHED TO A MANIFOLD ARE RECEIVING AIR AT THE SAME FLOW RATE, AND THAT FLOW RATE IS ESTABLISHED BEFORE ADDING ANY PATIENTS. THAT WAY THERE WILL BE MINIMAL OPERATING OF THE FLOW VALVES.

Testing

Testing was done with four ventilator ports per manifold flowing at 6 LPM; and with six ventilator ports per manifold flowing at 2.5 LPM.
Testing was done with four ventilator ports per manifold flowing at 6 LPM. It was not tested with six patient ventilator ports open.
Testing was done with eight patient ventilator ports operating at 2.5 LPM.
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