Lung Bioreactor Minutes

Meeting with Prof. Lima and Columbia surgeons scheduled for Friday at 4:00 pm
Plans to update wiki page.

Columbia surgeons back out on meeting. Rescheduled for Tuesday at 5:00 pm. One student member of the group will join Prof. Lima and take notes for the group.

Columbia surgeons deem our team to be unimportant- meeting cancelled; not rescheduled yet.
Plan to schedule meeting with a few of the surgeons soon to discuss project.
Columbia team will be harvesting lungs Friday February 4 at 11:00 am and Monday February 7 - students may attend to observe.

Prof. Lima showed us an existing device that can be sewn on pulminary vein after artery is cut.
We're going to gather already existing pieces (chambers, pumps, tubes, etc.) to assemble.
Can the bioreactor be tested by actually connecting the lung from the bioreactor to the person and then if it works fully place it inside.
We will research tubing, pumping, pressure/flow/pH/CO2, etc. sensors, and storage options.

Prof. Lima went to surgeons' meeting at Columbia
Columbians are shooting for a grant deadline of March; so we have about a month to make some drawings to put into the grant
Prof. Lima sent relevant pictures and videos about project

Decided to start working on basic prototype by testing pumps and tubes that are available
Short term goal is to effectively pump proper amounts of solution into and out of a dish
Plan to take inventory of available equipment available at CU and Prof. Lima will check with the Columbians to see what's available
Debated between bag and hard cased bioreactor - leaning towards bag for now
Resolved to split lung even before placing in bioreactor (a) lung is split anyway when replaced; (b) will allow for a better distribution of decellularization solution

Met with Professor Lima. We discussed methods for ventilation and creating negative pressure in a bag. Decided on negative pressure expansion system. Either a tightly sealed bag and the bag expands, or rigid cylinder with piston attached to displace media. Discussed possibility of a permanent bag (that will go into the body with the lung). Discussed transparent liquid media to detect leaks.

We put together a list of functions:
Containment
Allow expansion
Gas exchange
Means of blood circulation
Means of blood expansion
Sterility
Monitoring

Resolved to begin prototyping negative pressure system. Begin with function diagram and put together several systems. Reference historical examples.

Worked on QFD.
Prototyping for 2 designs in separate groups

Planned to look at heart machine and take pics
We got permission to shadow Columbian surgeons. very exciting.
Resolved to prototype negative pressure system at volume

Arrived at Columbian security offices, failed to produce proper documentation. Be advised for future to give advanced notice to security offices of our arrival.
18th floor- met Dr. Gopal Singh; introduced to staff and Babe.
Swine Operations (before euthanasing and removing lung):

• placed line in corroded artery
• placed oral airway through mouth to lung; separate inhale/exhale lines; (used absorbent pellets to get rid of CO2 from air)
• (Tested wound dressings on pig's femoral arteries)
• cut through flesh along length of torso (avoiding urethra); sawed through (double) sternum
• removed half of liver and gall bladder to create working space
• cut through protective membrane over heart and lung; heart, left lung, and diaphragm were exposed (and photographed)
• took skin samples and used to sew up leaking, gushing, and spurting heart

Simultaneously euthanized Babe, harvested heart and cut off ventilation. (squeezed and played with heart)
Right lung was now exposed and lung was fully extracted (they cut out leaving about an inch of trachea on the removed lung)
Pulmonary vein and artery were also exposed to a lesser degree. (Took note of 4 sub-PV's)
Ran saline solution using hand-syringe pump (however, for human would use gravity mechanism) in order to clean out and prevent clots within the lung
Slight discoloration was immediately noticed in the lung as result of collapsed alveoli
Placed lung in a saline filled bag; lung can only last in this solution for several hours (however in freezer lasts longer)
Dr. Gopal Singh advised that for human lung we would use Perfadex (saline based solution- for details see: http://www.vitrolife.com/transplantation/index.cfm?page=61F1027C-E606-454D-70EF930D4809B6BB); this solution would be longer lasting and proper media for lung to bathe in

SDS (decellularizing solution) would be pumped through blood vessels then afterwards through trachea- this is in order to note if the alveoli has been punctured and would result in the SDS exiting through whichever part it is not being pumped into
After which the SDS needs to be thoroughly cleaned out of lungs and tubes (we suggested an in between stage in which the tubes and lung were ran through with saline solution in order to thoroughly rinse the system, and Dr. Jeff said that that would be plausible- allowing a central bioreactor making use of the tube splitter)
Dr. Gopal Singh advised that blood substitute would be used in lung in the bioreactor can be used in a loop, but would have to be replenished APPROXAMITELY every two days.
Dr. Jeff confirmed that perfusate would be similar to amniotic fluid
The negative pressure would need to allow 8 cc per kilo of bodyweight per breath; Dr. Jeff epiphanized that because the breathing is not to sustain the body, but rather to keep constant flow through the lung, we would only need to allow as few as 6 breaths per minute (while avg human is 12-20).

Dr. Gopal Singh took us to see the current decellularizing chamber
this chamber is not sealed nor sterile for the pig and would need to be heavily modified for human medical use
also doesn't address several other relevant issues to be later discussed.

Discussed daily life of a surgeon - their job and their breaks.

In Dr. Gopal Singh's office we discussed in detail the physiology of the lung and the three big problems that we have to address:

• Collapsing alveoli (as soon as we cut off ventilation the alveoli have nothing to sustain them other than relatively weak surfactant)
• Clots in blood vessels
• During SDS process we need to ensure that it does not puncture any part of the lung, but is still powerful enough to decellularize
  

Yaron suggests to harvest lung while inflated and staple in order to keep alveoli supported by the air (Dr. Gopal Singh agrees heavily and confidently- and says he will try this with pig on Thursday).

We were introduced to Chief Dr. Joshua Sonett (Chief of thoracic surgery in Columbia and Bill Clinton).

Went to Dr. Jeff's office and met Jo and did and saw nothing at all! Awaiting Jo's e-mail regarding further information of our nothing.
Pictures with captions to explain the Nothing are available on the protected page.

In conclusion, we experienced an interesting, exciting, informative, memorable, motivating, and fascinating day.

Yaron and Elli meet about rigid chamber prototype
NEED to discuss proper methods of cleaning out SDS from the Bronchioles - How much SDS is negligible? Does the negative pressure system properly wash Brochioles with SDS and then Saline Solution? Or would some sort of separate pump system?????

Yaron and Elli improving function diagram to actually be a function diagram.
Would like to propose negative pressure prototype to be completed by spring break

Resolved to finish a flowchart regarding the heart machine.
Discussed taking and using ventilator from Columbia to attempt to create the negative pressure system.

Met without Prof. Lima and Elli and Yaron recapped day at Columbia with the group(as summarized above).

Resolved to meet Thursday at 5 to discuss negative pressure prototype.

Discussed Elli and Yaron's rigid body prototype plans.
Want to switch certain parts as will be noted when the diagram is posted.
Intend to get Columbian pump and heater and ventilator.
Intend to soon purchase a see-through chamber.
Need to research types of pump connections (such as panel mount things).
Want to check how they would sterilize tubes - using autoclave or a gas sterilizer.

Reviewed prototype plans.
Malcolm filled us in that Gopal said that we need to switch to air in the trachea as the last step, and that we can vacuum out liquids from lung with worry of it collapsing because some liquid will always stay in.
Prof. Lima proposed possibility of keeping the lung in a bag with minimum amount of perfadex (to save money) and using water surrounding the bag to create the negative pressure.

Meeting potentially scheduled for Thursday at 5.

Met to discuss a bill of goods - what we will need, amounts of each, and approximate pricing. (See Bill of Goods sheet)

Finalized Bill of Goods with prof. Lima
Intend to get all equipment from Columbia next week

Discussed fixing up and continuing wiki pages

Discussed PowerPoint Presentation - Slides will include: intro to topic, requirements & function tree, solid works &explanation of negative pressure system, solid works & explanation of tubings and fluid flow

Gopal will be out until March 29, but we can still get panel mount connectors and other materials to at least start some sort of prototype for next week. We should start thinking about duck-bill valves and how they may come in handy.

Looked over 12-month budget grant. We are requesting about 32,000 USD in the current draft. This may be an underestimate for the animal costs.

Grant has 2 possible schematics of bioreactor using same components. Separate and independent lung chambers (in series) allow for precise experimentation, while running in parallel in spatially and materially efficient. Using these sketches, the nest step is to draw them out in greater detail. (this includes exact panel mount locations, tube lengths, etc…) The series and parallel may have to differ significantly, or they may be fairly similar. We also have to look into tube cross section size. We also have to figure out PV connection. It has four subveins, and an open circuit may not be a viable option.

In conclusion:

• Sketch with size, location, and part no. (parallel and serial)
• PV solutions. (get pics)
• start actually looking into sensors. Get educated
• To bag, or not to bag? (could the bag be drainable?)
• Side by side comparison of our design v. secret heart thing (theirs is probably better)

Next meeting on Monday @ 5 (at least one person should come) [cancelled]

Discussed options for fluid flow and negative pressure system that would minimize time any tube would spend in the pump (to prevent wear&tear)
Intend to stop fluid flow for several moments to replace reservoirs to minimize need for switchers and to minimize number of reservoirs sitting around
Also, looking into renting sensors temporarily

Decided to build system with tubes and reservoirs with just the pump missing a so we can get somewhere meanwhile.

Consulted with Joshua from Cole-Parmer about tubing. He said we can get up to 5,000 hrs on expensive tubing. Good news. They can also handle the different fluids. Also spoke to him about one-way valves. They have spring powered w/.5 psi breaking pressure.

Perhaps we should come up with different pump soln's while we are waiting. Gravity may we a viable option.

Wondering whether Perfadex is external media during the whole process or only during the decellularization.

Ordered connectors from Cole-Parmer to get started on chamber.

Looking into reservoirs (with 3/8” inputs).

Josh hasn't been responding. Can't find 4-way valves. We may have to use 2 3-way valves. Or we can switch the reservoirs and suffice with a 3-way.

Heating may not be necessary for all reservoirs. Probably for recellularizing. We should look into it for everything else.

Going to talk to Josh about sterile media bag. He can advise with reservoirs and switching. (See schematic and bullets below for specs)

Put together more comprehensive (and simpler) schematic for reservoir-tube system for trachea and blood (very exciting utilization of resistance). Going to draw and post on wiki. So for each chamber:

• 3 3-ways
• 8 Quick Disconnect (QD)
• 2 1-way valves
• 2 y connections
• At least 7 1L reservoirs
• Ventilator they use during surgery for gas (easy to control tidal vol.)

WE HAVE TO GET DETAILS ON ALVEOLI ISSUE

Went over tube complex from last meeting and tweaked (corrected previous minutes). So we need 3 holes on top of each lung chamber and two on the side to go to -ive pressure pump. Perhaps wedge the chambers to optimize the flow through the -ive pressure pump.

Going to edit new sketch before scanning in. Clear up ambiguities, correct flaws, and add rough dimensions.

Elli and Yaron are not around this and first half of next week. We want to start drilling in shop this week. BUT NO PANEL MOUNTS!!!

Upcoming Tues presentation: it will rock ur sox.

Preliminary final goals: have panel mounts drilled to chamber, with some tubing and switches, and mock reservoirs. (and some -ive pressure demonstration if we have some sort of pump available)

Discussed shop. We should drill holes. Julian can do it tomorrow.

New Presentation Approach: chronological overview of project, rather than problem solution. Journey through our experience (demonstration of effort may compensate for our lack of hardware) everyone knows our project by now and we don't have anything new to say, but it could be interesting to talk about it experientially and less technically

Went through minutes and composed word doc of major checkpoints.

slide visuals:

1. cover and problem
2. fcn diagram (abridged version) (first prototype, discuss splitting into research teams (show wiki pages))
3. bullet points (Medical Team Rosdevous, got informed major medical issues ahead, general process, different sides different times, some technical points)
4. first schematic (2 teams one rigid one bag, chose rigid, -ive pressure)
5. Lung split decision
6. air gas for trachea, potential bag, pressure in series (use pic from grant request!), potential pump problem and resolution
7. most recent autocad schematics (different changes…)
8. bill of goods and lima grant request (project is much larger than this semester…)(talk about hardware research with cole parmer, anthony's email, etc…, talk about progression of bill of goods)
9. sum up, acknowledgements, take away (pic of chamber with holes and tubes and whatnot)

Discussed pump problems (see project progress):

1. will tape down lid when the chamber is refilled and see if the 'lung' will drain better
2. will retry negative pressure with as few connections used as possible and look for improvement

Will get CP working on sending over the new pump head and figuring out what the problem is with the one-way valves
will send over tubing for IR analysis
hope to meet with the Columbians on Friday (need to be done there by 5:00pm)

Met with Prof. Lima
intend to send pump in to Cole Parmer as a return (due to the noise problem)
Decided that the sterilizing air filter will do, and we do not require autoclave-able gas flow meter

Met with Prof. Lima
reviewed sketch (see main wiki page) and discussed that we would want this drawn neatly on computer
discussed that it would not be a problem to place a sensor in-line using a T-fitting even though the sensor would be 3” long
discussed that we cannot just autoclave the tip of a sensor, but could dip in alcohol to sterilize
(Checked with Dione that autoclave is 131 degrees C)
Plan to look into purchasing pump that is more reliable - nothing from Cole Parmer or Masterflex
Want to avoid connections as much as possible - even at the cost of losing stainless steel sensor option
Want to avoid using check valves and switch to solenoid valves that can be programmed using arduino

Need to check with Columbians about what machine they use to pump/produce the oxygen; and
what sensor is in the artificial lung.

Decided that we wanted the more expensive autoclave-able DO probe rather than potentially alcohol-able DO probe.
Want to return current pump and move on to the I/P series of Masterflex pumps
Meeting with Columbians tomorrow at 4:00 pm

Elli, Igor, and Dr. Lima met:

Discussed problems with current chamber
Plan to build our own chamber from scratch to hold the pressure we need

Moved wiki to Senior Project page
Plan to reorganize wiki to be a better source of information and dispose of all EID103 related class assignments

Elli, Igor, and Dr. Bacchetta met:

Discussed that we will start working with human lung segments - chambers will be about 15*15*15 cm^3
Rather than the 8 mL per kg of lung donor body weight, we will only require 6 mL
Confirmed that 6 breaths per minute will work
Lung segments will be in the range of 1/3 of one of the lung lobes - exact segment volume to come later

Reviewed with Dr. Bacchetta that we will now be designing our own chamber

Linda said that she has not heard back from Spectrum Medical yet; recommends I contact them directly.

Elli and Igor met:

Discussed the current set up of what he have working and how it works
Discussed additional problems for us to deal with:

1. Need to solder wires and switches, rather than having them in breadboard
   
2. Need better solution of having the wires plug into the back of the pump
   
3. Eventually need better reservoirs rather than the Ziploc bags, but for now those DO hold and are easiest to bleed air out of
   
4. CHAMBER
   
5. Need to re-wire the arduino/pump on/off switch so that it works
   
6. Need to decide where in relation to the chamber we want the reservoirs
   

Elli Igor and Prof. Lima met:

We need to map out the pressure situations in the 2 chambers from the starting conditions of the lung

• tube resistance to trachea - do we want to not use one-way valves in order to minimize resistance
  
• initial conditions would include air at the top of both chambers
  
• use one-way valves that can also be closed completely to bleed air out when necessary
  

We will try to use a rectangular chamber or flatten some edges of the cylindrical chamber in order to ensure that we can properly get the panel-mount connectors in
We set a 2 week deadline (Oct. 24) on hearing from Spectrum Medical on the sensors and at that point will purchase our own
Need to get and read the paper on the machine (with sensors and solenoids and other exciting stuff) that Delogamatikas has
Want to meet with the students who designed that machine this Monday

Elli, Igor and Prof. Lima met:

Looked at glass jars with aluminum screw on lid
Due to aluminum's flexibility the lid was not secure at all
Sinisa said he would be unable to fix a custom lid for the chamber
Sinisa will be machining for us a cube chamber with dimensions 20^3 cm
Chamber will be made bulletproof in order to ensure maximum protection of the human lung and with have latch top lid
We will bring Sinisa our panel-mount connectors to ensure proper hole size
Holes will be placed with 2 towards the bottom of one of the sides and and one on each towards the top side of a wall, and probably one in the lid for one way pressure release valve.

We want to recover all of our equipment from Columbia in order to work here
Unable to go Wednesday evening
Elli and Igor will attempt to go on Monday to bring all back

Went to see Mindy at 30 Cooper for potential presentation help - she was not in

Elli and Prof. Lima met:

Plan to order O-ring and clamps soon
Clamps to be used over butterfly-nut system because clamps will be easier and as it is adjustable it should hold tight

e-mailing Spectrum Medical for purchase information for their products

Will set up meeting with Columbians soon to discuss where we are and what we need to purchase.

Elli and Prof. Lima met:

Discussed how to respond to Donna from Spectrum medical - will be asking to have their system within the next 2 weeks and to keep it for at least 2-3 months
Decided to use panel mount connector in lid to attach to pressure release solenoid valve or check valve or manual ball valve
Sinisa finished chambers on his end - we have to bring him the clamps (already received), the panel mounts, and the O-rings to finish up the job
Elli and Igor packed up Columbia and brought all back to Cooper Union

Elli, Igor, Prof. Lima, Dr. Singh, and Dr. Bacchetta met:

Happy with current chamber design
Will have human lung segments available mid-November - plan to transport segments to Cooper Union and work in our laboratory
Will not need to measure DO at any point
Also, we can ignore air flow for now
Will need pressure sensors and all flow will need to be altered depending on pressures - each lung will have a max pressure
Control everything (sensor readings, pump control, and all feedback) through several Arduino micro-controllers
We need to have both pulmonary and trachea side up and running equally as important - will order second pump for pulmonary flow soon
Confirmed that we will want temperature sensors to monitor a temp of 37 C
Discussed possibility of placing more than one lung segment in a chamber - however at lung inflation it could be about 10 to 15 cm large, so we cannot fit two