Journey

STANPUMP and Open Source

SimTIVA's mathetical calculations to PKPD are based on STANPUMP, a computer program created by Dr. Steven Shafer, written in C programming language and runs on MS-DOS. As its core, STANPUMP gives SimTIVA the ability to solve the equations to CP and CE targeting. It is very generous and visionary of Dr. Shafer to share the source code to STANPUMP on the public domain (available on OpenTCI) so that many other PK and TCI simulators could be built upon STANPUMP's pharmacokinetic engine, not to mention many more pump manufacturers who build TCI pumps based on Dr. Shafer's work.

My programming skills are limited. SimTIVA started off as a small personal project, and my initial task was to transcribe STANPUMP (written in C) to JavaScript, which I am more familiar with. Today, SimTIVA has grown into a somewhat mature product and has attracted some international recognition. This is a stage which I had not imagined.

To take this project forward, as encouraged by a few of you in the scientific community who are interested in pharmacology and programming like I am, I have decided to put the source code of SimTIVA on the public domain. This will ensure transparency and hopefully like-minded enthusiasts can edit, improve and maintain the code in the future. Follow the link to GitHub here to see the code.

TCI for everybody

Although TCI technology has been around for decades, there are many places that are not equipped with TCI pumps. A notable example is USA where there are regulatory constraints. Also, even if hospitals have TCI pumps, they may not have the latest Eleveld model, which is a broad population based model and simplifies TCI delivery in a number of specific patient groups, particularly the morbidly obese. SimTIVA bridges this technological gap and it is vital that SimTIVA remains free and available to all, so that those interested in TCI technology will be able to learn about TCI and run TCI simulations and not be limited by pump, hospital or regional regulatory constraints.

The PK models, including the latest Eleveld model, of propofol are freely accessed in the literature. The codebase to STANPUMP, the PK engine used in many simulation programs and pump devices, is also free. SimTIVA hopes to continue this tradition to share an easily accessible app, based on these PK models and also the PK engine of STANPUMP, freely to the anaesthetic world.

Acknowledgments

I wish to thank Dr. Eric Ng, Dr. George Zhong, Dr. Alexander Clarke, Dr. David Lam and most importantly Dr. Steven Shafer for their time in correspondences on email and Twitter to encourage me to take this project in the right direction.

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