There is no advantage to use the yellow flexible MULTI sockets

There is no advantage to use the yellow flexible MULTI sockets

for differentiation of patient monitors

NIHON KOHDEN uses the yellow shared-use MULTI sockets to differentiate patient monitors developed in Japan against those that are developed in China, which is why the SVM-7000 series monitors do not offer the flexible  yellow MULTI sockets (and related "Smart Cables"). The use of flexible MULTI sockets is considered a "premium" feature only reserved for patient monitors developed in Japan by NIHON KOHDEN.

 

Nothing is actually lost, because it is not technology and the market is telling the manufacturer to abandon it as soon as possible.

 

The key point to highlight here is the fact there are attempts to send a marketing message, without offering any proof, that there are patient-monitoring hardware embedded in the so-called "Smart Cables", and we are going to show you beyond doubt there is no basis to this claim.

 

Under US rule, a cable is only a cable if it does not change the signal that passes through it. A Smart Cable embedded with a non-volatile digital hexadecimal code is just a cable and does not change a signal passing through it, but if it has an amplifier it becomes a medical device and definitely requires FDA registration. Can you find any stand-alone NIHON KOHDEN Smart Cable registered with US FDA as a medical device? We do not.

Make no mistake, when the Smart Cables are used with serial kit sets, such as mainstream CO2 kit sets or the NMT AF-101P kit set, the registration is for the active serial kit set (just like any other manufacturers) and not the passive Smart Cable. 

 

Messages such as "New Modular Technology" and "The Module is in the cable!" are just the wild imaginations of people without the necessary electronics knowledge.

 

What do the manufacturer mean by this statement? 

It started with the Life Scope TR (BSM-6000) series monitors in the USA market and gradually adopted officially for International markets. These are precise statements.

The constant iteration of the same assertion while avoiding to provide any proof does not make it the truth!

 

This is just wild assertion without showing any proof

 

Chip makers need huge demand to justify each of their products, it is unlikely any manufacturer would want to take losses by taking such low-volume business from NIHON KOHDEN. When we opened up the plug of a Smart Cable, we found see a small flexible PC board being soldered to some pins of the yellow plug (as shown below).

 

A small PC Board is soldered to some pins of the yellow connection plug

 

Upon inspection, the PC board confirms a cheap non-volatile digital EEPROM chip is being used to custom code each Smart Cable.

 

A non-volatile cheap digital EEPROM chip was what we found inside the yellow Smart Cable plug

The Smart Cables are each programmed with a digital hexadecimal code to identify the type of hardware needed by the measurement cable; the code is also known as the parameter-selection code.

 

Overview

 

The hexadecimal code is programmed in the non-volatile EEPROM at the factory and cannot be changed by operator setting after production. It is not difficult to make the Smart Cables but they are being priced highly by the manufacturer; only the common IBP cable can be sourced from China suppliers at a reasonable price.

 

A parameter code is stored in the plug of the measurement cable

Below is the plug of a compatible IBP cable from China suppliers, they just copied the digital code defined by NIHON KOHDEN. Do you really think they managed to put an active IBP amplifier inside?

 

Back in the 1990s, it was just a quest to find a solution for a small module with a front panel with insufficient space area to mount all the necessary sockets needed.

 

The special need that was searching for a solution

The problem was not unique to NIHON KOHDEN, with the most common solution in the market being to integrate more than one signal onto a socket, and using an external splitter to obtain back the original individual signals. The interesting solution from NIHON KOHDEN was, however, to share a small number of common sockets.

NIHON KHODEN managed to identify five types of analog hardware (Temperature, IBP, Cardiac Output, Thermistor-method Respiration, FiO2) to form a hardware group frugally sharing just two sockets flexible for group use. The two flexible sockets are known as MULTI (short for multi-parameter) sockets and are specially colored yellow.

 

The hardware group and flexible sockets together made up the MULTI-PARAMETER UNIT (MPU), and was only a peculiar design to reduce the number of physical sockets needed on a panel with limited space area; thus, the MPU has the unusual characteristics of having more hardware than physical sockets. In other words, it is a design to optimize use of a fraction of needed physical sockets, and is operating under constraint of limited sockets.

 

The MPU must be viewed in the right perspective, that it is illogical to use when panel space area is not a problem, because we should typically be optimizing the use of relatively expensive hardware instead of cheap sockets; it was a trade-off of flexibility vs. sufficiency.

 

It was a design to have flexibility over sufficiency, taking advantage of the space constraint for limited sockets

To access each type of hardware, an external measurement cable with a digital parameter code stored in its plug needs to be inserted into one of the two MULTI sockets. These measurement cables that come with yellow coded plugs are collectively cited as Smart Cables by the manufacturer and each embedded digital parameter code pinpoints the exact type of internal hardware needed by a particular measurement cable.

 

If specified, the included hardware are placed internally in the MPU before leaving the factory, just like any configured monitor.

 

Principle of Operation

 

Each socket selects only one channel of the hardware, except for Temperature allowing two channels of hardware to be selected.

 

As an exception, a MULTI socket can be linked to two channels of Temperature hardware

 

A MULTI socket can additionally switched to be a pass-through path for

digital serial data packet from any serial kit set

 

Again, like a configured monitor, the MPU can accept use of serial kit sets for capability extension (supported by necessary software). This is done via the parameter code, whose execution means to bypass the internal analog hardware and go directly for digital processing. As is common knowledge, the identity of a serial kit set is contained in the header of the data packet; it will not be processed if the system software does not support it.

 

Using a parameter code, the MULTI socket can switch to be a transit point for any digital serial data packet

 

 

The older manuals [before June 2007]

have the details

The Life Scope BSM-2301 bedside monitor was launched in 2001, and the Service Manual is clear on the design; manuals for later models stop providing such information. The major move to curb details in manuals started from Life Scope J (BSM-9101) Bedside Monitor, which was launched in June 2007. The Life Scope TR bedside monitors also do not provide details, as it was launched in April 2008 (after Life Scope J monitor).

 

In BSM-2301 service manual, you can see the IBP and thermistor respiration are internal hardware inside the Life Scope BSM-2301 monitor. These hardware are clearly shown being linked internally to the yellow MULTI socket, and to make use of either hardware, a Smart Cable with the correct code must be plugged into the MULTI socket.

 

The block diagram also shows us the MULTI socket of Life Scope BSM-2301 monitor cannot measure Temperature because there is no Temperature hardware linked to it; and the sole Temperature hardware is dedicated to an external jack. This observation is further confirmed by the label for the yellow MULTI socket indicating PRESS/ CO2/ RESP, i.e. no TEMP. This block diagram clearly shows there is no reason for any amplifier hardware to be placed inside the NIHON KOHDEN Smart Cables.

 

The manual confirms the IBP amplifier and thermistor respiration hardware are internal components of the Life Scope BSM-2301 monitor

 

The block diagram also shows the flow of the serial data packet bypassing the internal analog hardware and going straight to the digital APU (Analog-block Processing Unit).  For a parameter using the internal analog hardware, the analog signal needs to be converted to digital before it can go to the APU for digital processing.

 

The manufacturer had already quietly conceded

the yellow flexible MULTI sockets are indeed poor man's sockets

In 2001, a popular Life Scope BSM-2301K (also known as Life Scope i) was launched and many customers bought it for standalone applications not restricted by system compatibility. It was popular because the Life Scope BSM-2300K series range of monitors were the first in the industry to adopt the new-generation type 8.4-inch high-resolution touchscreen introduced by the electronics industry. The new touchscreen display was a huge jump in touchscreen technology and made for highly-intuitive operation, hence its popularity. The company tried to attribute its popularity to the use of Smart Cables and a flexible MULTI socket. Let's see if this is true.

 

The portable 8.4-inch Life Scope i (BSM-2301K)

 

 

The key issue is one multi-purpose socket

cannot concurrently do the jobs of three fixed-purpose sockets

 

To insist the use of Smart Cables, the Life Scope BSM-2301K monitor has a flexible yellow MULTI socket for three types of measurements, namely:

 

1. Invasive Blood Pressure

2. Thermistor-method Respiration

3. Mainstream CO2 (using self-contained serial kit sets)

 

Without any use of Smart Cables, all three parameters (IBP, Thermistor Respiration and mainstream CO2 are freely available for carefree use via their respective dedicated sockets. The use of Smart Cables makes things unnecessarily complicated and requires deliberate operator attention and choice to choose one among three (IBP, Thermistor Respiration and mainstream CO2), but why introduced a need to choose? This is bordering on frivolity.

 

It is obviously unwarranted stress and inconvenience, what is wrong with the conventional way of using three dedicated sockets for the job? If MULTI socket is such a superior proposal, why is the Temperature socket a dedicated one?

 

This is compromised usage, like a poor man affording only one physical socket for three types of use

 

The reality is the shortage of two physical sockets for users. However, one of the parameter for the yellow MULTI socket is thermistor-method respiration, which is for use in the operating room to overcome electrical noise interference; this parameter is therefore not for use in the ward. The real shortage felt by users is only one missing physical socket, and they are not hesitating to demand it back. Imagine the initial wonder of a flexible socket turned into an outrage for being shortchanged!

 

Users do not want to be shortchanged with a poor man's socket

The manufacturer was pressured to respond with an updated model, Life Scope BSM-2303K. The solution from new model BSM-2303K is to add a new isolated yellow MULTI socket that can only do IBP monitoring.

 

The MPU of the Life Scope BSM-2301K was not designed to take on expansion, and any additional MULTI socket will load (disturb) the operation of existing MPU, causing it to malfunction. The additional (fake) MULTI socket is not linked to the MPU, just an independent socket with its own dedicated IBP amplifier hardware. Such was the additional yellow socket offered for Life Scope BSM-2303K, considering there was a need to recognize and use the same IBP Smart Cable.

With a new socket for IBP, the existing MULTI socket can move away from doing IBP monitoring, and just focus on being a serial port for mainstream CO2 or being an amplifier for respiration monitoring using a thermistor transducer.

 

It was ironical, a solution relying on an extra dedicated socket for IBP; there are now two IBP amplifier hardware in the monitor, which was not the original intention. It was clear the complaints was the result of sharing a flexible socket and the solution offered by Life Scope BSM-2303K was to return back one of the two missing physical sockets needed by users.

 

Market rejection forced the manufacturer to return back the missing physical socket demanded by users