James Walton
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Within the medical arena there is increased pressure on budgets and financial accountability, with a significant trend for the sector to look again at how resources are used and where savings can be made.

One of the largest expenditures in most hospitals is the cost of purchasing or producing the various medical gases needed, such as Medical Air, Nitrogen, Oxygen and Nitrous Oxide. Often the usage and consumption of these gases is neither monitored nor measured or, whenever it is done, it is often a crude estimation, inaccurate and recorded only by pen and paper.

Most hospitals rely on the rate at which the cylinders (in which the gas is supplied) empty to determine the amount and rate of gas used. There are of course many issues associated with this method, such as:

  1. The amount of gas in a particular sized cylinder can vary greatly, even when directly delivered by the gas supplier
  2. Total gas consumption and peak times of consumption cannot be accurately determined
  3. Leaks can go undetected
  4. Specific point of use consumption is impossible to determine

This makes it very difficult to manage costs overall and to assign invoicing costs to individual departments and sections.

A company specialising in the design, installation and maintenance of gas systems was asked to install the medical gas network in a new hospital. An approach was made to Bronkhorst UK Ltd for the supply of gas meters which could then be communication-linked to the building maintenance system.

Thermal mass flow Instruments with integrated multi-functional displays were offered to fulfil both the accuracy and reliability requirements . As a result of their through-flow measurement (Constant Temperature Anemometry - CTA technology) the thermal mass flow instruments offered the additional benefits of no risk of clogging, no wear as there are no moving parts, minimal obstruction to the flow of the gas and hence ultra-low pressure drop, all based upon the fact that the instrument body is essentially a straight length of tube.

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In addition to the local integrated displays both 4…20 mA and RS232 output signals were available ensuring integration with the Building Management System (BMS). This gave the end user real time continuous data logging and remote alarming should the gas supply enter low- or high-flow status for any given event. As a double failsafe the instrument offers both on-board flow totalization and further hi/lo alarms.

The installation of the mass flow instruments for this hospital application provided the following benefits to the client:

1. On primary networks:

  • Separated invoicing for hospital/clinic/laboratory departments sharing the same source of medical gas
  • Monitoring and acquisition of consumption data
  • Leak detection within gas line, safety vent and medical gas source

2. On secondary networks:

  • Independent gas consumption invoicing between the health institution departments
  • Over-consumption detection
  • Monitoring and acquisition of consumption data
  • Leak detection within gas line

Subsequent installations across Europe have followed the trend of increased accountability by installing a Mass Flow Meter for the incoming bulk delivery, obtaining a totalized flow reading and cross matching this to the bulk invoice. This could be useful in the event of inadvertent errors or typos when a bulk delivery invoice is being raised.



Application note

Frank Nijsen
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This is a guest blog by Frank Nijsen (CSO of Quirem Medical).

The toolbox of an oncologists who is faced with treating liver cancer, is still limited. Fortunately, a new tool will be added shortly to target advanced unresectable liver tumours: microscopic beads loaded with the radioactive isotope holmium-166. These so-called microspheres are brought onto the market by Quirem Medical (Deventer, the Netherlands) as QuiremSpheres®. Recently, QuiremSpheres® was named a top 5 Dutch medical technology innovation [1].

QuiremSpheres® consists of millions of tiny microspheres. In fact, the microspheres are smaller than a third of the diameter of human hair. Nevertheless, their impact on liver tumors can be huge. The mode of action is twofold: (1) once introduced in the bloodstream to the liver tumours, the microspheres block the hair vessels supplying oxygen and nutrients to the tumours (embolization) and (2) beta-radiation, emitted by the radioactive holmium-166, kills tumour cells from close range (radiotherapy). It is because of this dual action that the treatment is called radioembolization. Various clinical studies have shown the efficacy of radioembolization for treatment of liver tumors while patients only suffer relatively mild side-effects.

What makes QuiremSpheres® so unique?

QuiremSpheres® microspheres are based on more than 20 years of research and development at the University Medical Center in Utrecht (UMCU), the Netherlands. 15 years ago, radioembolization was already an existing, but largely unknown, treatment method for liver cancer. The researchers at the UMC Utrecht wanted not only to promote the usage of radioembolization, but also develop a new type of microsphere with unique imaging advantages. And they succeeded. The microspheres that were developed cannot only be imaged with SPECT imaging, but also with MRI. By means of these imaging possibilities, the treating clinician can follow the microspheres after they have been injected in the liver artery and assure that the microspheres actually reach the tumours. In addition, Quirem Medical provides proprietary software to precisely calculated the dose that was delivered to the tumour and to the healthy liver tissue.

Manufacturing QuiremSpheres®

The microspheres are synthesised at the production site of Quirem Medical in the Netherlands. During synthesis, holmium-165 chloride is converted into holmium-165 acetyl acetonate crystals, which are mixed with polylactic acid in a solvent. This solution is combined with an aqueous solution, after which microspheres with a size of approx. 30 microns are being formed. The solvent has to be evaporated, and Bronkhorst mass flow controllers deliver the nitrogen flow to enhance and control the solvent evaporation. After washing, sieving and drying, the batch of holmium-165 loaded microspheres is ready. The total synthesis takes almost two weeks.

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After the production of the ‘cold’ holmium-165 microspheres, a vial containing 33 million microspheres is activated by neutron bombardment in a nuclear reactor. The resulting active holmium-166 microspheres are then transported to a hospital for implantation into the patient. The limited half-life of holmium 166 (26.8 hours) means that good reactor-to-hospital logistics is of key importance.

A few company facts ...

Quirem Medical BV is a spin-off from the University Medical Center Utrecht (UMC Utrecht) in the Netherlands. The CEO of Quirem Medical, Jan Sigger, has held numerous senior management roles in the (petro)chemical and medical devices industry. Frank Nijsen, CSO of Quirem and associated professor at the UMCU, has already more than 15 years of experience in the (clinical) research and development of holmium microspheres. In April 2015, Quirem has acquired CE-marking for QuiremSpheres®. Recently, Quirem Medical entered into a strategic alliance with Terumo, a major Japanese medical devices company.

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Curious? Take a look at the following links:

Microspheres for liver cancer treatment - Application Note

Website of Quirem

Reference [1] Rabobank Highlights – Dutch medical technology is going to change the world