update documentation to semi-final form

helpfulengineering · Nov 7, 2020 · 24ff8b0 · 24ff8b0
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diff --git a/docs/.ruby-version b/docs/.ruby-version
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+2.7.2
diff --git a/docs/README.md b/docs/README.md
@@ -7,3 +7,22 @@ DISCLAIMER: THIS IS NOT A MEDICAL DEVICE. These designs and documents are for ex
 This fully printable device with no moving parts is able to provide a continuous positive pressure to a patient's airways while letting them breathe freely.
 
 ![complete orthographic view](/assets/complete_ortho.png)
+
+## About the device
+This design provides a 3d-printable CPAP mask that can be manufactured in areas without access to standard CPAP or BiPAP equipment that has been shown to be desireable in COVID-19 patients [(source)](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7261654/).
+
+This device is not suitable for mass-manufacture, entities with the resources and logistics necessary should purchase either commercial electronic BiPAP or CPAP machines, or the Boussignac CPAP produced by [VYGON](https://www.vygon.com/).
+
+## Files
+
+Source files have all been generated in OnShape, as a public document. The source files may be found [here](https://cad.onshape.com/documents/fcc843822e3f2cb218bbe91c/w/738c68d83bd9079113df055c/e/e5dcf7b0527b1f57e8a51f64?configuration=barb_id%3D0.003%2Bmeter%3Bchamber_width%3D0.003%2Bmeter%3Begress%3D4.0E-4%2Bmeter%3Bpatient_channel_diameter%3D0.010%2Bmeter%3Btext_depth%3D3.0E-4%2Bmeter%3Bwall_thickness%3D0.002%2Bmeter). The design is parametric, so you may desire to tune the values to achieve different goals. The main parameter that users will want to tune is 'patient channel diameter', but the 'egress' parameter may also be tuned to account for differences in SLA exposure, resins, and finishing processes.
+
+| Item |
+| ---- |
+| [Mask](assets/CPAP Mask.stl) |
+| [10mm Valve](assets/cpap_valve_10mm.stl) |
+| [9mm Valve](assets/cpap_valve_9mm.stl) |
+| [8mm Valve](assets/cpap_valve_8mm.stl) |
+| [7mm Valve](assets/cpap_valve_7mm.stl) |
+| [6mm Valve](assets/cpap_valve_6mm.stl) |
+| [5mm Valve](assets/cpap_valve_5mm.stl) |
diff --git a/docs/assets/CPAP Mask.stl b/docs/assets/CPAP Mask.stl
diff --git a/docs/assets/cpap_valve_10mm.stl b/docs/assets/cpap_valve_10mm.stl
diff --git a/docs/assets/cpap_valve_5mm.stl b/docs/assets/cpap_valve_5mm.stl
diff --git a/docs/assets/cpap_valve_6mm.stl b/docs/assets/cpap_valve_6mm.stl
diff --git a/docs/assets/cpap_valve_7mm.stl b/docs/assets/cpap_valve_7mm.stl
diff --git a/docs/assets/cpap_valve_8mm.stl b/docs/assets/cpap_valve_8mm.stl
diff --git a/docs/assets/cpap_valve_9mm.stl b/docs/assets/cpap_valve_9mm.stl
diff --git a/docs/medical/README.md b/docs/medical/README.md
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+# Medical
+```danger
+DISCLAIMER: THIS IS NOT MEDICAL ADVICE. This is just some interesting data that real doctors may be referred to in order to inform their treatment decisions
+```
+
+## When to implement CPAP treatment
+This article has a useful algorithm to make decisions about the use of CPAP treament in COVID-19 patients, including considerations of FiO2 and other patient parameters.
+[https://www.medrxiv.org/content/10.1101/2020.06.05.20123307v1.full.pdf](https://www.medrxiv.org/content/10.1101/2020.06.05.20123307v1.full.pdf)
+
+## Effectiveness
+Article with information about the effectiveness of CPAP therapy in COVID-19 patients
+[https://www.medrxiv.org/content/10.1101/2020.06.05.20123307v1.full.pdf](https://www.medrxiv.org/content/10.1101/2020.06.05.20123307v1.full.pdf)
diff --git a/docs/testing/assets/regulator.jpg b/docs/testing/assets/regulator.jpg
diff --git a/docs/testing/equipment.md b/docs/testing/equipment.md
@@ -1,6 +1,9 @@
 # Equipment
 
-In order to verify the successful manufacture of the valve, the following equipment will be needed:
+Ideally, testing would be performed with a standard medical oxigen tank, regulator, and humidifier similar to this one:
+![Oxigen equipment](assets/regulator.jpg)
+
+In the absence of real equipment, the following may be substituted with care to match the characteristics of medical equipment.
 
 ## Air Supply
 
@@ -10,6 +13,8 @@ Air compressor with regulator, should be able to provide 15L/min @ 40 PSI
 
 Pressure compensated, should be able to limit to 15L/min to match standard medical equipment. Can be approximated with an 0.8mm printer nozzle @ 35 PSI. [Calculator for airflow](https://www.tlv.com/global/TI/calculator/air-flow-rate-through-orifice.html)
 
+To verify you're producing 15L/min, submerge a container of known volume in a large container of water. Place the air line (after the flow limiter) under the container and measure the amount of time it takes to make the container fill. E.G. with a 15L container that starts out completely full of water, the container should rise completely out of the water in about 1 minute, a 5L container should take 20 seconds. There is some wiggle room, but medical equipment is mostly limited to 15L, so accurate testing depends on accurate flow limiting.
+
 ## Manometer
 
-A manometer that can accurately show pressures in the 0-20cm H2O range is vital. A U-tube manometer is easily constructed out of clear vinyl tubing.
+A manometer that can accurately show pressures in the 0-20cm H2O range is vital. A U-tube manometer is easily constructed out of clear vinyl tubing. A printable manometer can be found [on thingiverse](https://www.thingiverse.com/thing:1205032)
diff --git a/docs/testing/procedure.md b/docs/testing/procedure.md
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+# Procedure
+
+Testing the valve is relatively simple, provided the necessary equipment is present. Two factors are highly important in testing and implementation:
+
+## Pressure
+
+Pressure and flow are interdependent, but the valve depends on pressure in order to generate the airspeed necessary to form the virtual valve. At the low flow present in medical equipment, even small leaks can result in pressure drops, so ensure that no leaks are present between the flow limiter and the valve. The valve's O2 port has been designed to accomodate standard oxigen line fittings with minimal leaks, but teflon tape may be used if leaks are present. 
+
+## Flow
+
+Standard air compressors have a much higher flow rate than medical equipment, so flow limiting is crucial. You may achieve good PEEP with your test equipment, then take it to the hospital and get terrible PEEP.
+
+## Testing the valve
+
+A video demonstrating testing [can be found here. TURN DOWN YOUR VOLUME](https://youtu.be/-pk_lfGOONA)
+
+Connect a soda bottle to your manometer via any means available, and insert the valve into the mouth of the soda bottle. Some teflon tape may be necessary to achieve a good seal.
+
+Valves come in a variety of channel diameters from 10mm to 5mm. These produce an increasing range of pressures. Depending on the calibration of your SLA printer, you may need to use a smaller channel to achieve your target pressure. The table below gives ballpark maximum pressures achievable with a well-calibrated printer
+
+| Channel Diameter | Pressure (cm H2O) |
+| ---------------- | ----------------- |
+| 10mm             | 6-9cm             |
+| 9mm              | 7-11cm            |
+| 8mm              | 8-12cm            |
+| 7mm              | 8-14cm            |
+| 6mm              | 9-15cm            |
+| 5mm              | 10-17cm           |