Showing posts with label innocentive challenge. Show all posts
Showing posts with label innocentive challenge. Show all posts

November 21, 2014

Innocentive NASA Challenge: Medical Consumables Tracking

As I am not authorized to share the details of the challenge, as per the agreement signed by me, I am sharing the overall structure of the problem here. Once you are through you may now look for the solution that I submitted, some more than 4 years ago. 
I am omitting "My Solution: • Introduction and Background: " part; as it may divulge  information from the challenge itself, which is prohibited. The below portion has not been altered post-submission, even though I could find many faults looking back. [I particularly could better have done without resorting to the undue rigmarole under this subheading: "Electronic cascading method". Should have explained my idea in simple terms and perhaps with some schematic, self explanatory diagrams. What I really meant was that each box would be like an element in an array of a 3D matrix (where the 3D matrix represents the array of medicine boxes for each day), and that each element/box would be assigned a unique value identifying it, corresponding to their orientation in space. This could be achieved by a process similar to DTMF encoding. The actual counting would still be done optically and the data sent to a memory module/register. Counting could be implemented by cascading binary coded decimal (BCD) counters.]  Below is the submission, uncut. 

"• Detailed Description of the Solution: The requested problem may be solved in a much better way than being done by standard bar-code (UPC= Universal Product Code=bar code) in a number of ways: such as, quick access time, minimum medicine handling, far higher accuracy, holds more data and ‘potential’ tracking to the ultimate end-user. 
An RFID device (Radio Frequency Identification) may look like a rectangular card, a ring, a wristwatch, wrist band, a bracelet or anything we may want it to be of the ‘required’ shape. We will concentrate upon both the ‘passive RFID tag’ (fig. 4), a batteryless device; as well as an ‘active RFID’, a battery incorporating device having an inbuilt antenna. They may be used both in a spacecraft and aboard the ISS. Before describing them it is pertinent to point out that the astronaut wear an ‘active RFID reader’ (interrogator module), whereas the medication boxes will contain RFID tags. Although this will marginally increase the power consumption, but it will certainly save more box space.    

The ‘passive RFID label’ contains a batteryless circuit which may be inductively (Loop of wire) or capacitively coupled. Although we prefer the capacitively coupled one, here we briefly discuss the actions of an inductively coupled one, as it is easier to understand. A miniature in-built coil within the RFID label produces ‘induced electricity’ that powers the rest of the circuit, when it nears an RFID reader (the wristband). The EMF (from ‘induced electricity’) then transmits all the data, the RFID has been preloaded with. It may include user data, time, quantity in stock etc., which the ‘wristband or ring device’ sincerely relays to a nearby computer, PDA, mobile phone (??Service provider in Space!), or a USB memory stick.

RFID is already in use in tracking cattle, dispensing medicines, checking medical inventory, managing expired/counterfeit medicine, etc.; and it is approved by the FDA for most of those stated. The tracking may be employed in two major ways:

1). The conventional method: 
(Step A): The ‘inventory’ would be designed as shown in fig.1. A postage stamp has been pasted on the ‘main’ door to symbolize the ‘main’ RFID tag. Behind the main door are an array (fig.2 & 3) of medical boxes arranged in a week’s course (the grid may be modified according to need). Each day-numbered-boxes has their own unique ‘sub’ RFID labels (tags). These RFIDs have been exemplified in fig.3, as red/black circular pads. All the RFID tags will have information regarding the type of the medicine, quantity, expiry and other issues as needed. Quantity remaining will be conveyed by the passive RFID tags stuck to the boxes, when they are approached by RFID readers via RF communication to the server. It also records the identity of the person. Subtracting doses is done by knowing the drugs taken and in which amount. 
This is laser ‘optically’ determined (we can’t weigh them since gravity is virtually non-existent) or an ejection-related electrical contact system may emit an RF signal . Replenishing the inventory may be done in an analogous way. 

An audible/visible alarm may be preset on the day (or before as desired) of expiry of any particular medicine, injection etc., or when empty. This arrangement of boxes in the XYZ coordinates (fig. 3) will help us determine which meds are taken or needs refill.

(Step B): Each astronaut has his/her own specific RFID reader. Each reader is attached directly or by Bluetooth transponder to a nearby computer, PDA, mobile phone (??Service provider in Space!), USB memory stick, or any other server.

Example: Consider this scenario: Mr A volunteering to bring a caplet for Mrs B. Mr A goes to the inventory, brings his battery powered ‘active’ RFID reader enabled ‘wristband’ near the ‘main’ console which is ‘passive’ RFID enabled. ‘Active’ sends coded RF signal to the ‘passive’ RFID sticker. The ‘Passive’ device now knows the user’s identity from its database, sends back this info to Mr A’s wristband, which again relays info to the Flashdrive/PDA etc.. The ‘main’ console opens, allowing access to the individual boxes of pills to Mr A. Supposing, Mrs B wanted a pill of Calcium tablet, Mr A would this time use “her wristband/RFID reader” to individual boxes until he gets to the right rack (each box contains pre-encoded medications). He gets the caplet, her wrisband subtracts the total amount of the pill by ‘one’(this is done in the PDA/mobile/USB drive, with cues from optical/electrical signal, sent via RF). The pill has to be either ejected mechanically or the person have to finger-pick them (the box has to be bigger then). 
Thus, we know who opened and who was the actual recipient (patients’ information system, or PIS). Obviously, we did not see Mrs B ACTUALLY taking it, but we may rely on the cosmonauts’ honesty. Otherwise, optical monitoring/radiolabelling of medicines have to be done (this is NOT desirable)! [We may however, implement capsule endoscopy containing actual active ingredients too (and videograph/send RF signal, as well)!]

Here at this stage we need to use a software to do all the tedious job for us. Software programs are written using HL7 organisation protocols (Health level seven is an American National Standards Institute accredition organisation). The server processes data received from PIS. The server would have no problem forwarding the medication related information to a physician.

2). Electronic cascading method: 
The medication array remaining the same, we may encode each ‘box’ a specific tune (frequency) just as we do in DTMF (dual tone multi frequency) telephones. These frequencies will provide us with the requisite address/bus location, in addition to relaying to a centralized server. Electronic counter low power CMOS integrated circuits incorporating overflow (for cascading signals) like 4553 may be employed. They may be interfaced with 74HC4543 BCD to 7 segment decoder ICs to produce visible LED digit displays for the astronauts, alarms; or they may be FSK-ed (frequency shift keying) to a database and transmitted as required.

In either case, the volume and weight of the inventory will easily be within the specified limits, provided not too many medicines are required by the persons.

PS: Ready made medicine dispenser with builtin inventory and alarm are available in the market. I have included some such sites in references.

References and Notes: 
http://www.openpcd.org/
http://en.wikipedia.org/wiki/Radio-frequency_identification
http://www.rfidjournal.com/article/print/778 (smallest rfid reader)
http://www.rfidcardreaders.com/rfidreaders.htm (rfid reader interfacing)
http://www.eng.tau.ac.il/~yash/kw-usenix06/index.html (how to build an RFID skimmer)
www.eahp.eu/content/download/25218/164530/file/DugDistribution71-73.pdf.pdf (USING AUTOMATED DISPENSING MACHINES)
www.rfidjournal.com/article/articleview/1511 (RFID and Emerging Technologies Market Guide to Healthcare)
www.rfidjournal.com/article/articleview/3777 (Radio Frequency Identification in Health Care)
www.rfidjournal.com/article/print/7713 (Hospital RTLS Tracks Pumps' Status and Movement)
www.rfidjournal.com/article/view/7671 (USAF Boot Camp Tracks Boots)
http://www.iautomate.com/products/RFID-PC-Security-Kit.html (RFID PC Security Kit)
http://www.ftc.gov/os/2005/03/050308rfidrpt.pdf (FTC "Radio Frequency Identification: Applications and Implications for Consumers" (March 2005))
http://www.epill.com/medtime.html (AUTOMATIC MEDICATION DISPENSER)


Attachments:
Fig 1, Fig 2, Fig 3, Fig 3a, Fig 4

• Supporting Information: vide References 

• Conclusion: This solution is likely to conform to the ‘seeker’ standards, as it is:
gravity independent
Minimal hand work
Space saving
Accurate inventory tracking
Technically and financially feasible"

Addendum: links to Fig 1, Fig 2, Fig 3, Fig 3a, Fig 4
Last modified: never 
Reference: hyper-links, unless specifically mentioned

Innocentive Theoretical Challenge: Heart Implantation of a Medical Device

I must say that I am not authorized to share the details of the challenge, as per the agreement signed by me. Yet you can have a glimpse of the overall structure of the problem here. Once you have seen the salient points you may now look for the solution that I submitted to them way back in 2010. 

I am free to publish my proposed solution, which also sheds some light on the deeper requirements for the leadless device. However, I am omitting "My Solution: • Introduction and Background: " part, as it may divulge  information from the challenge itself. The truncated portion that appears below has not been altered post-submission, even though I could find some faults retrospectively. Below is the un-altered submission. 

"• Detailed Description of the Solution:

As is conventional with these procedures, the patient is venepunctured (using aseptic and anesthetic precautions) in the groin and the femoral vein is accessed.  The Leadless Device is introduced retrogradely to the inferior vena cava and thence to the right atrium of the heart. All these procedures should be undertaken while under fluoroscopic control is assisted by echocardiographic guidance.  

The LD may be conveniently delivered to its location, discussed later, by using a fiberoptic endoscope, which in addition to ‘being guided’ by the fluoroscopic/ echocardiographic screens; can visualize the anatomy of the right atrium and the right ventricle that lie proximally. 

In a study by Fujimura et al (fig 1, =Ref 3) a 3.6 mm diameter fiberoptic endoscope (with a latex balloon) was used to study the right heart anatomy of anesthetized dogs. The distal tip was inserted into the right atrium, where the balloon was inflated with air in 5 mL increments. Thus, it seems very likely that we could explore the human heart using a fiberoptic device having a diameter of around 4mm. The endoscope will, in fact, help to locate the best anatomical co-ordinates in the right heart (ventricle) where the LD may attach (reversibly). 

The LD must be secured to the RV (septum, wall or the apex). This could be done in the following ways:

1. Modifying the LD shape (fig 1), so as to incorporate a ‘groove’ in it (fig 2) or as a ‘O’-ring at its ends (fig 2), which could act as an anchor for LD to the RV.

2. The ‘modified’ LD may then be either sutured to the right ventricular myocardium using:

a)atraumatic suture using fiberoptic guidance,
b)Better still; secure the LD, with the help of silastic rings, as is done in male sterilization.
c)An inflatable occlusion balloon (as in Foley’s catheter); that may be deflated, when necessary, for re-implantation (fig 3); BUT the volume of the balloon may interfere with the stroke output of the Right Ventricle, though that is miniscule, by physiological standards.
d)Or, depositing the device in the pocket of the moderator band (septomarginal trabecula) (fig 4)

Whichever way the LD is secured, the LD should be preferably anchored in a transversely approach, as a longitudinal placement may enable the LD to a ‘greater strain’ (RV axis; Ref 1) while the ventricle is contracting.

It is quite obvious that some coverage of anti-thrombotic episodes must be provided during the procedure. This may include low molecular weight heparin therapy or therapy by aspirin or other pharmaceutical agents, so that the implant does not initiate a thrombotic episode, due to the LD’s irregular (or, perhaps its wettable surface) surface terrain.

However, once the LD is implanted in the cardiac tissue; the irregularities in surface may, in fact, stimulate cell growth and adhesion (chronic endothelialization) (Ref 2; Patent application number: 20100063562 )

Thus, the LD will finally adapt to the cardiac tissue in a way that the LD will not be a deterrent to normal functioning of the heart.


• References and Notes: 

Ref 1: Septomarginal trabecula (also see wikipedia: http://en.wikipedia.org/wiki/Septomarginal_trabecula), the septomarginal trabecula (or moderator band))
Ref 2: Chronic endothelialization (LEADLESS TISSUE STIMULATION SYSTEMS AND METHODS)

Fig 1
`
Fig 2

Fig 3

Fig 4


• Conclusion

The LD being 25mm/7mm will have no problem negotiating a catheter of 8mm diameter (24 Fr catheter). The volume of the LD (962.5 mm3 or 0.0009625 L) is too small to have any practical hemodynamical impact on the stroke volume of the Right Ventricle (5 L) which is equal to the output of the left ventricle. Moreover, the implanted payload is expected not to interfere with the right heart function hemodynamically (0.0009625 Liter of the vol. of the LD vs. 5L of cardiac output), antigenically (medical grade polymer) or thrombogenically (clotting). The non-metal, silastic ring or atraumatic sutures will not cause undue ‘electromagnetic shielding’ of any electromagnetic radiation the LD might emanate, neither would they pick up stray electromagnetic disturbances. The securing of the device by silastic ring or atraumatic sutures will keep our options open regarding the choice of re-implanting elsewhere, if needed. 

Thus it seems that the present approach is arguably one of the best approaches possible for a reversible implant of a Leadless Device onto the right chamber of the heart."

Addendum: Ref 2 link
Fig 1, Fig 2, Fig 3, Fig 4

Last modified: never 
Reference: hyper-links, unless specifically mentioned