Archive for the ‘Cyprane mk3 vaporiser’ Category

Mk 3 Vaporisers.
more photographs by me in the illustrated version of this article.


This is a very easy vaporiser to clean.
Remove 4 grey plastic caps at each corner and with a 4mm hexagonal key, undo the 4 bolts holding the top on. Clean off the deposits on the brass face of the top and also the bottom part.
Use Halothane, Trilene or Ether.
Blow away any fibres that may have been left behind by the cleaning cloth, no lubrication required, re-assemble the top, tighten the 4 bolts and replace the grey caps.
As a general rule DO NOT use any abrasive cleaning compounds, and NEVER under any circumstances use wire wool or sandpaper.If, however, you do get one really stubborn bit you can use a metal polish but you MUST clean away any remaining polish afterwards with Halothane, Trilene or Ether, if you don’t it will continue to slightly abrade after reassemble and every time you turn the top.

Trouble with the click stops on the control knob:
Remove the two screws holding on the circular plate on top of the control knob, remove the plate.
Undo the large screw in the centre and remove it along with its washer, lift off the control knob. Remove the woodruff key (the small half-round piece of metal that keys the top to the spindle).
The click stops are provided by the small nylon pip at the front, there is a spring underneath it, it will either be stuck or the spring is weak or missing. Repair as necessary.
The sprung pip at the rear is to balance the front one.
The orange off position release button is on a spring held on by one screw.
Replace the woodruff key with the top part into the groove more than the bottom part otherwise you will have difficulty getting the top back in place. It may need a little juggling and a tap with a soft hammer or a piece of wood to get the top on.
Replace the large central screw and washer and the top cover and two screws.

To get to the wick, turn the unit on its side and undo the 4 screws underneath the lip of the unit, pull the top away complete with the wick assembly.
Inside you will see 4 bolts which hold on the filler unit and the sight glass unit.
These should not be disturbed unless you have to replace the seals, sometimes, if the unit has been dropped, they may work loose. Tighten them with a spanner, do not over tighten or you may damage the seals.
The drain cock may be removed by loosening it a few turns and undoing two countersunk screws.
There is a seal on the end of the shaft, do not damage it. Unless you have a replacement there will be little you can do to it.

If you do not have one use a piece of wood. Do not use a metal hammer, not that it won’t work but simply that it will damage the chrome.

Re-assemble in the reverse order and test.
Check that the taper connections at each end are round, if not make an anvil, slightly smaller than the hole in the connector, out of a piece of wooden stick, hold it in a vice and tap the connector round with a soft hammer, i.e. one with a nylon or similar head. If you do not have one use a piece of wood. Do not use a metal hammer, not that it won’t work but simply that it will damage the chrome.

I’ve just found a little piece in the operators manual for the Mk3 vaporiser made by CYPRANE, or OHMEDA (BRITISH OXYGEN) as it is now called, there are quite a few of these vaporisers around so it is worth setting it out in case it is of any use to you but I do stress that it is written for the Mk3 vaporiser sold by CYPRANE and more than likely won’t apply to other vaporisers.
The checking method below can be used where specialist equipment is not available for checking the calibration.
The characteristics of the vaporiser is such that if the vaporiser is correct at one setting it should be satisfactory at all other settings.
1. Check that the vaporiser has been filled and has been at an ambient temperature of 22c for at least three hours.

2. With the vaporiser securely mounted, open the drain until no more liquid will run
out and then close the drain.

3. Check that the dial is turned off and carefully and quickly refill with a measured
amount of anaesthetic agent without spilling, use 70ml, close the drain securely.

4.Leave the vaporiser at about 22C for 1 hour to ensure that the temperature
has stabilised.

5. Set a flow rate of 5lpm. of oxygen.

6. Turn dial to 2 %, note the time and check that the flow rate is still 5lpm.-readjust as appropriate.

7. Leave the vaporiser at this setting for 30 minutes, check the flow rate now and again, turn vaporiser off and turn the oxygen off.

8. Drain until no more liquid will come out and measure the amount of liquid drained off.

The amount of liquid consumed in ml should be in accordance with the table below.
Make sure that you exhaust the gas outside.
Fluotec 13.5
Enfluratec 15.5
Isotec 15.5

It should be appreciated that the above test method is designed to be quick and easy under ordinary hospital conditions and that the method is somewhat imprecise.
Nevertheless, it would be unusual for measured liquid consumption to vary from that given above by more than 25%.
This is a simple procedure and although the firm say it is imprecise, it is worth doing if you have no other means of testing.
In general terms, it is recommended that vaporisers are returned to their makers or agents from time to time.
If you have your own analyser you should check the output on a regular basis.
If you find that the error is more than +/- 10% of the dial setting, (at 2%, 1.8 ~ 2.2), the unit should be returned to the makers for re-calibration.
Any errors you find should be reported to the anaesthetist, let him decide if the unit is fit to be used.

Cutaway diagram.

Tec 3 Cut_Away

Tec 3 Schematic

Tec 3 Sump_Valve Assy 01

Thanks to General Anaesthetic services and in particular, Andrew Wall for the above diagrams.

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