Category Archives: Maintenance

Fixing things

MCKelly – ALS part 2

I have nearly finished the upgrade of one of our MegaCode Kelly’s as referenced here.  Well, that’s not for the faint of heart.  I’ve seen the ResusAnne Simulator SimPad upgrade kit which is very complete.  All of the little bits and pieces (cable ties, anchors, hoses, etc.) which are included in that kit need to be worked out and sourced independently for this upgrade.

This does require a complete tear-down of the manikin.

The main board mounting plate needs to be re-drilled to accommodate the larger main board.  The lower left corner stays in the same place and holes are drilled to match.  The load board moves directly up to clear the main board.

main board drill pattern

Here’s a photo of what it should look like when re-installed in the manikin.  Notice that the load board extends over the edge of the cutout in the manikin.

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The next big modification is the chest.  The lung occluder servos end in a fitting 13mm OD.  The end of the trachea (just past the bifurcation) is 19mm OD.  The original ALS has a molded adapter tube to join these parts.

IMG_20130925_162124

I made up a stack of flexible PVC hoses (13mm ID, 16mm ID, 19mm ID) to make this transition.  There was also a change in lung design at some point.  I really like the idea of a screw connector to replace the lungs, so kept our old grey lungs for the time being.  Eventually, we’ll switch to the new white style lungs.  I cut a 20mm sprinkler riser in half to make this connection. It screws into the end of the lung occluder assembly and secured to the lung with a cable tie.

IMG_20131001_171207The connection to the pressure sensors uses about 300mm of 3mm ID PVC hose.  This hose also fits the connections on the chest rise bladder and the hose from the thigh tank.  It has a larger OD, but opening out the chest plug with a drill worked OK.

Finally, the thigh tank reservoir.  I couldn’t stand the schraeder valve (bicycle) connection and wanted this to interface with our standard wall air setup.  This required some slight modifications to the thigh tank assembly.

I removed the schraeder valve and the rest of the components temporarily.  Note that this assembly consists of the fill valve, reservoir tank, relief valve, 10 psi regulator, 8 psi regulator and finally a solenoid valve.  I have no idea why Laerdal chose to put in two regulators set so closely together.  I also noted that the locking nuts on the regulators came loose fairly easily and needed to be re-tightened.

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On the first leg I managed to break the hose barbs off both the inside of the schraeder valve and the Tee fitting that screws into the tank.  Note that the clear hoses are 1/4″ OD and DO NOT fit into 6mm push on-fittings.  Thankfully, 6mm soft poly tubing has the same ID as the original and fits nicely.  The Tee replacement I used was a 6mm x 1/8″ thread tee from SMC pneumatics.  I also installed a check valve in the thigh assembly between the tank Tee and the external fill hose since the QD we’re using doesn’t seal on the plug end.

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I drilled a couple holes in the side of the fill penetration for a cable tie to hold the fill hose securely.  The fill hose ends in a KK3-P quick disconnect which I put down the trouser leg for connection to the wall air source.

SMC parts used in this modification included:

  • KQ2T06-01NS (only if you break the original Tee) $5.40
  • KK3P-06H Quick disconnect plug end $6.10
  • KK3P-06S Quick disconnect socket end for the hose that goes to the wall – this is self sealing so you can change manikins easily without disconnecting from the wall. $16.70
  • KCH06-00 AKH06-00 Check valve with 6mm push-on fitting at both ends $13.50
  • KK2F06-01-X2 straight 6mm – female 1/8″ thread to connect to the hose barb which comes out of the wall $4.70
  • From other suppliers: 1/4″ x 1/8″ thread male tailpiece (hose barb), a bit of 1/4″ ID hose and a hospital wall air nut.  The photo below shows a slightly different arrangement of fittings, but does the same job.

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The compression sensor had to be soldered to the cable end left conveniently in the chest plate.  The hall effect sensors in the head are still a work in progress.  I need to go look at the original again to confirm exact placement and may have to fabricate a mounting plate.

Not particularly difficult, but there’s lots of steps and bits and pieces to sort out and source, so it took some time.  We’ll see how it holds up over time and abuse by medical students.

Air fittings for manikins

We frequently move our manikins from place to place and were having a problem with the push-on fittings used by the Laerdal manikins.  Over time, the tube would get damaged and not release properly.  I fixed this by replacing the push-on fittings in the regulator box with a proper quick disconnect – a KK3 from SMC Pneumatics.

The KK3S (socket/female) has an internal check valve.  I have set this up on the hose that comes from the wall.

SMC KK part numbers

The corresponding male/plug bulkhead fitting (KK3P-06E) was used on the regulator box and other manikin connections throughout our centre to allow consistent connection of air.

Inside the regulator box, a short tube stub connects to a 6mm push-on tee to replicate the original configuration.

qd

This is a sample of the hose that connects from our piped wall air.  There is a short section of reinforced hose crimped with appropriate fittings.  This is adapted to 6mm polyurethane “push-on” compatible air tube which finishes with the KK3S for connection to various manikins.

ResusAnne Simulator and the ALS Simulator will take the 55psi (380 kPa) nominal wall pressure easily.  Their relief valves are set to 10 bar (145 psi = 1000 kPa).

Replication of the regulator box was accomplished using an SMC AR20-02H-01 regulator (0.2MPa spring) with appropriate fittings and pressure gauge.  The output is set to 110-120 kpa per the Laerdal regulator box spec (1.1 Bar +- 10% = 15.95psi (109 kPa)).  The double lumen tube that connects to the manikins connects to a bulkhead fitting from Colder (PTC16020) with 1/8″ hose barbs.  These will take a 6mm OD push-on hose with a bit of heat and persuasion.

This arrangement could use a relief valve to protect the manikin in the event of a regulator fault.  I have this setup on our SimBaby and SimNewB cots.

KK3P-06E

IV Arms for Laerdal manikins

I got tired of having mouldy IV arms and disgusting skin, not to mention the effort and expense required to change the skins.  The replacement skin and veins alone are $383 + GST!

It turns out that Laerdal make a different style of arm for their Nursing Kelly manikins that are directly compatible with SimMan Classic, MegaCode Kelly and ALS Simulator.  This is an articulated arm with a simple pad insert to allow limited IV insertion.  The arm is part number 300-05150 and retails for $264 + GST.  The insert is part number 300-04050 and retails for $42 + GST.

replacement IV arm IV arm insert

We generally don’t even connect up the tubes, but simply provide this insert as a location for inserting an IV.  Fluids and drugs are administered via our bung and tube setup.