NIHON KOHDEN SVM-7000 series patient monitors made in China and Malaysia

Category: Product Review, Shanghai Kohden Patient Monitors, Nihon Kohden SVM-7000 series monitors

It is the first being designed and with all parts sourced in China

Do note it is not NIHON KOHDEN Life Scope SVM-7000 series monitors but just NIHON KOHDEN SVM-7000 series monitors.

 

The SVM-7000 series has the following models from China

1. SVM-7501 10.4-inch monitor

2. SVM-7503 10.4-inch monitor

3. SVM-7521 12.1-inch monitor

4. SVM-7523 12.1-inch monitor

The SVM-7000 series monitors are the first being designed by a team from Shanghai Kohden with all the parts sourced entirely in China; SVM stands for "Shanghai (Kohden) Vital (Signs) Monitor". Compare the statement with that of the Vismo PVM-2700 series which are designed in Japan while the parts are sourced in China. Vismo stands for "Vital signs monitor". Before the Vismo monitors, the Life Scope BSM-2300 series monitors was designed in Japan with parts sourced in Japan.

 

The SVM-7000 series multi-parameter patient monitors are the first in the series; this means all components, quality control and design are handled from China. The quality of the product is of course similar to manufacturers in China who are getting their components from the same sources as NIHON KOHDEN.

Why are Free Sales Certificates not available for exports from China?

 

Notice there are two models with Invasive IBP parameter, and these need clinical trials in China for approval to sell in the country. The models with invasive IBP parameter are therefore not allowed for sales in China

 

This means Certificate of Free Sales from China cannot be provided for all models; these models are offered only Certificate of Export Sales. An alternative assembling site must be found to solve this problem.

 

Standard models from CHINA

 

In Malaysia, there is a loophole to get regulatory approval for models with invasive BP parameter even though there is no regulatory approval from China or Japan.

 

The models assembled in Malaysia are assigned a different number from that assembled in China and they are all approved for sales in Malaysia:

1. SVM-7601 10.4-inch monitor

2. SVM-7603 10.4-inch monitor

3. SVM-7621 12.1-inch monitor

4. SVM-7623 12.1-inch monitor

 

Standard models from MALAYSIA

 

Two types of colored frames

The standard color of the frame is white while the models with black frame are reserved models for OEM negotiation with interested parties. 

 

This effectively means distributors who are successful with the standard white frame models face the possibility of additional supply coming into the market in the form of the black frame models as competitors.

Standard frame is the white one while versions with black frame are open for OEM negotiation

 

To bring down the cost of a product, manufacturers typically reduce the amount of total hardware used and also saving cost by using cheaper components which are of a lower MTBF (mean time between failures). Contrasting against the SVM-7000 series monitors by Nihon Kohden are products from Edan Instruments, Inc. from China whom we are aware could offer monitors with high MTBF comparable to those produced in Japan.

 

The eight models of SVM-7500 and SVM-7600 series patient monitors

 

The operation of the monitors is only by touchscreen and with two display sizes, at 10.4 and 12.1 inches with a 800x 600 resolution.

Below table shows the details of various models from China and Malaysia respectively (including the versions with black frames); there are two models for 10.4 inch display screen and another two models for 12.1 inch display screen. According to the table there is no difference between SVM-7501 (China) and SVM-7601K (Malaysia) for example, only the assembly location.

 

SVM-7500 series models from CHINA and SVM-7600 series from MALAYSIA

 

 

You should find more assembling sites than just China and Malaysia

 

It is very easy to assemble any SVM-7000 series monitor in any location around the world, there is no reason to restrict assembling production sites to only the two locations mentioned in this article. In the USA for example, NIHON KOHDEN AMERICA already has a history of assembling their own models PC-based Electroencephalograph and Evoked potential/EMG measuring instruments for sales in the US Neurodiagnostic market, and the subsidiary can easily add the SVM-7000 series monitors.

How to check if the country of origin is Japan?

Officially, you should know the country of origin in writing for an export; the product label is another source of information from the factory.

 

Below picture shows the product label for ECG-1150 ECG machine, whose production site is in China. The product label does not indicate the country of origin is Japan, since there is no specific mention of "Made in Japan". Do not mistake the corporate address as production site.

The Product Label for above ECG-1150 whose Country of Origin is China has no "Made in Japan" declaration

 

In next picture, the product label for BSM-1102 similarly has no indication "Made in Japan" because this was a third-party product made outside of Japan. The address just indicates ownership of the product model. In the same picture, the lower label for Telemetry Central Monitor WEP-4208A clearly show the product was made in Japan.

If Country of Origin is Japan, it is indicated on the product label "Made in Japan"

The SVM-7000 series monitors are not for sales in Japan

The SVM-7000 series monitors do not make use of the common-use yellow multi-parameter sockets, this is the straight-forward confirmation that the products are not meant for the Japanese domestic market. This is further confirmed by the fact there is no provision of interface for the digital telemetry networking which is standard for a Life Scope Patient Monitor. Clearly, this range is not sold in the Japanese domestic market and there cannot be any Free Sales Certificate from Japan MHLW.

The SVM-7000 series monitors cannot be mixed with Life Scope or Vismo monitors in a patient monitoring network

 

Missing is a brand identity for the SVM-7000 series patient monitors since it is not associated with Vismo or Life Scope brands, just the generic parent brand. Brand identities of Vismo and Life Scope are not strong any way, they are mostly just known as Nihon Kohden monitors.

While Vismo and Life Scope patient monitors can work together in the same real-time network (inter-bed, central monitoring), the SVM-7500/ SVM-7600 series patient monitors do not share the latest networking protocols and cannot be on the same monitoring network.

We also noted the iNIBP measurement is not deployed in the SVM-7500 and SVM-7600 series.

 

The common-use yellow multi-parameter sockets as differentiator for patient monitors developed in Japan and China

 

NIHON KOHDEN uses the yellow common-use multi-parameter (MULTI) sockets to differentiate patient monitors developed in Japan and China, and that is why the SVM-7000 series monitors do not make use of such yellow common-use sockets (and related "Smart Cables"). The use of yellow 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. We have discussed the archaic concept of a MULTI-PARAMETER UNIT (MPU) elsewhere and the yellow MULTI sockets are a part of the MPU.

 

The key point to highlight is the fact there is no patient-monitoring hardware embedded in the so-called "Smart Cables", and this makes a big difference in how you appraise a monitor that comes with MULTI sockets.

 

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 continued repetitions of an assertion without offering 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, so which chip manufacturer is supplying NIHON KOHDEN the variety of analog chips given the extremely low volume in demand? If we were to open up the plug of a Smart Cable, what do we see? A a small PC board is seen being soldered to some pins of the yellow plug.

 

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

 

The PC board confirms a cheap non-volatile digital EEPROM chip is being used to code the 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

If we were to open up the plug of a compatible IBP cable from China suppliers, what do we see? It is the same thing, a plug with a digital code.

NIHON KOHDEN had identified five types of hardware (Temperature, IBP, Cardiac Output, Thermistor Respiration, FiO2) that can be linked from the inside onto the MULTI sockets and to make use of these hardware, a measurement cable with a valid code must be plugged into one of the MULTI sockets. The code selects the internal hardware needed by the measurement cable and is also known as the parameter code. Note the selected hardware are linked from the inside to the common-use yellow socket, and not from the outside!

 

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

 

Principle of Operation

One socket can select two Temperature hardware channels.

Each MULTI socket can take two channels of Temperature measurements

Irrefutable proof the IBP amplifier hardware is configured internally, an important fact no longer shown on later monitor manuals

 

The Life Scope BSM-2301 bedside monitor was launched before the Life Scope TR and Life Scope J bedside monitors, 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 before the Life Scope TR bedside monitors.

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.

 

Can you see the IBP amplifier and thermistor respiration hardware are internal components of the Life Scope BSM-2301 monitor?

The MULTI socket doubles as a serial port without any need for internal monitoring hardware, only as a link to the monitor. In the block diagram below, the processed digital serial data from a CO2 kit set goes straight to the digital micro-controller APU (Analog-block Processing Unit) and is forwarded to the DPU.  For a parameter using the internal analog hardware, the analog signal needs to converted to digital before going to the APU for digital processing.

Using the yellow MULTI socket as a serial port is only meaningful when facing the constraint of panel space area, it is otherwise illogical.

Relevant page in the combined Service Manual for BSM-2301A, BSM-2301K, BSM-2303K, BSM-2304A

What you had just seen is that the number of yellow MULTI socket on a monitor is not an arbitrary number, but peg to the number of internal IBP hardware channel intended. Adding an extra yellow MULTI socket has the unintended consequence of adding another channel of internal IBP hardware. Take a step back and ask the question, why do you need such yellow flexible sockets? 

It does not bother the manufacturer that use of Smart Cables and flexible MULTI sockets has negative captured value for users

The use of Smart Cables has unintentional negative captured value for the users, as can be seen from below illustration. Users of the left monitor (BSM-3500 series with 2 channels of IBP) requires five connection sockets but only two yellow common-use sockets can be provided for sharing. The internal IBP hardware channels intended for this model is only two, and therefore limited to two yellow MULTI sockets. 

 

Without any use of Smart Cables, all five parameters are freely available for carefree use via their respective dedicated sockets. The use of Smart Cables just makes things unnecessarily complicated and requires deliberate operator attention and choice to choose two among the five, but what if you need all? This is unwarranted stress and inconvenience, and the use of five dedicated sockets is obviously a far superior design!

 

Similarly, users of the right monitor (BSM-3700 series with 3 channels of IBP) requires six connection sockets for carefree use but the manufacturer insists three yellow common-use sockets are enough for use. This just means the manufacturer only wants to place 3 channels of IBP hardware in the MPU of the BSM-3700 series monitors, which is possible for a protected Japanese market, but not for export.

 

How does such dire shortage of connector sockets benefit a user? The apparent flexibility of the yellow MULTI sockets is in reality an adoption with negative captured value for the users.

 

These monitors are in dire short of necessary connector sockets, the value captured by users is negative

Beware the mandatory need for electrical safety of monitored patients

When networking a patient to a hardwired Ethernet network, the typical non-isolated Ethernet from NIHON KOHDEN is a danger to patient electrical safety. Network Isolation Units are mandatory to ensure safety of patient from electrical shocks.

 

NIHON KOHDEN network isolation transformer

When an isolated monitor with an non-isolated Ethernet port is connected to a hardwired network, it is no longer a medical device unless the above-shown network isolation transformer is introduced between the monitor and network. If the network isolation transformer is not installed, dangerous electric shocks can be delivered to a monitored patient through the wired Ethernet network. Such dangerous electric shocks are potentially lethal and no hospital should ignore this mandatory requirement.

WATCH OUT the dangerous use of semi-quantitative CO2 measurements and ignorantly displaying a flawed CO2 waveform

Nihon Kohden lacks sidestream CO2 sampling expertise and buys OEM units to offer them as expensive standalone. The AG-400 CO2 unit as shown, for example, is technology from Oridion Medical. For monitoring such as post-surgery recovery, integration of the sidestream CO2 into the monitor is a mandatory requirement because an external unit requires additional power socket besides necessitating the use of a trolley.

 

For some unknown weakness, Nihon Kohden monitors have never been able to offer benefits of integrated sidestream CO2 measurements.

 

The inability to integrate the sidestream CO2 unit into the patient monitor main unit

The adoption of semi-quantitative mainstream CO2 measurement was to reduce cost and its simplicity also help in miniaturization of the transducers. The first solution offered by Nihon Kohden was the mainstream cap-ONE TG-920P CO2 sensor kit (order code P907) that can be used on non-intubated patients.

 

The cap-ONE TG-920P CO2 sensor kit (order code P907) has very small sensors because semi-quantitative measurement is adopted, the method is not commonly seen and many are not aware of the risks of obtained CO2 readings from the semi-quantitative CO2 kit sets, and to make matter worse, the semi-quantitative measurements are also being made used of to display a flawed continuous CO2 waveform.

 

Nihon Kohden cap-ONE P907 (TG-920P) mainstream CO2 sensor kit

 

The SVM-7000 series monitors do not make use the yellow MULTI-parameter plug, below picture shows the type of non-coded connector plug being used on the SVM-7000 series monitors.

 

TG-921T4 semi-quantitative CO2 sensor kit for SVM-7000 series monitors

 

How to remove a relatively big disposable adapter from the two tiny transducers after use?

When the sensors become smaller, it also means the disposable adapter becomes relatively much bigger as seen in this below picture. When trying to remove the disposable adapter from the transducers, it is difficult to separate the two because of the latching mechanism. A small size transducer means anything that latches onto it must be even smaller.

It is not easy to separate the disposable adapter from the Cap-ONE transducers after use

 

When removing disposable adapter from the mini sensors, users tend to just pull from the cables and this action quickly weakens the joint holding the sensors and cables. The action will cause stress to the two joints and quickly degenerate the performance of the transducers. This means the transducers are unlikely to last.

 

Users just doing the inevitable

 

Shown below is another TG-900P etCO2 kit set (order code P903) that makes semi-quantitative CO2 measurements on a traditional mainstream CO2 sensor. The TG-901T3 kit set (order code P906) is the same thing but using a non-coded connection plug. The medical devices from same manufacturer that make use of semi-quantitative CO2 kit sets for patient CO2 measurements and waveform include:

- Life Scope patient monitors

- Vismo patient monitors

- Cap-STAT OLG-2800

- CardioLife defibrillators

- Neurofax EEG machines etc.

 

Nihon Kohden semi-quantitative CO2 kit sets with traditional mainstream transducer

 

The manufacturer is not aware semi-quantitative CO2 measurements are only estimates

 

To save costs, the semi-quantitative kit sets do not make measurement during the inspiration phase. The important point is there is a measurement duty cycle and it is as shown; there is no way to know the actual CO2 measurements during the inspiration phase because CO2 measurements are not made.

Semi-quantitative means there is a duty cycle, and measurements are not continuous

 

Semi-quantitative measurement is also of low-accuracy type, performed using one IR detector instead of the usual two to save cost. This is reflected in the measurement tolerance.

 

Contrasting, quantitative measurement delivers high accuracy for critical care. To ensure the necessary high accuracy, quantitative measurement employed two IR detectors for simultaneous CO2 measurements at different wavelength for results comparison. CO2 measurements are also being made continuously.

 

Quantitative measurement employs two detectors to make continuous measurement at different wave-lengths to compare readings for high accuracy

NIHON KOHDEN specification for TG-901T CO2 sensor kit shows even the specified low accuracy of CO2 measurement using semi-quantitative method no longer holds true once CO2 is present during the inspiration phase.

This is because actual CO2 value will be more.

Semi-quantitative design cannot assure users the CO2 level is definitely zero during each inspiration phase!

 

Measurements are invalid when CO2 is present during inspiration, but the design does not measure the CO2 level during this period

As seen from the duty cycle, there is no measurement being made during the inspiration phase, how does the manufacturer assure measurement accuracy? The specified measurement tolerance is conditional and has no meaning for the users!

Each semi-quantitative CO2 measurement is in fact only an estimation.

In addition, since the users are not alerted on screen there is no CO2 measurement being made during the inspiration phase, they are unknowingly made to take on an unnecessary risk.

 

Semi-quantitative methodology means cost-effective estimations but the design cannot be used in a general way, only on a selective basis with known risks

 

For example, semi-quantitative methodology can be used as a simple estimation tool for obtaining the numerical value of End-tidal Carbon Dioxide level (etCO2).

 

Below picture shows the semi-quantitative method in the way it was intended for, estimating only the etCO2 numerical value for purpose of airway tube placement confirmation. It is not for continuous waveform display.

A hand-held semi-quantitative etCO2 estimation tool (with SpO2) for airway tube placement confirmation

The manufacturer ended up ignorantly displaying a flawed continuous CO2 waveform using semi-quantitative measurement kits that do not have ability to make continuous measurements

 

NIHON KOHDEN also allows data from semi-quantitative measurements to be displayed on screen with the non-measurement period reset to zero level. The insistence to display a continuous waveform using discontinuous measurement data from semi-quantitative mainstream CO2 estimation kits is irresponsible, and the manufacturer is subjecting the monitored patients and users to dangerous misinterpretation risks.

 

A zero CO2 reading on the waveform means zero measured value. No measurement can only mean a defective sensor, not by design!

Note the end-tidal CO2 (etCO2) value shown is also not alerted as "estimated etCO2" only.

 

A flawed CO2 waveform with non-measurement intervals reflected as zero measured CO2 value

As seen from the two true CO2 traces below, expiratory upstrokes do not always start from zero CO2 level!

Quantitative measurements confirming expiratory upstrokes do not always start from zero CO2 level

Check the latest updated table to make sure you only use quantitative method for critical measurements and displaying a true CO2 waveform on the screen.

 

Use only quantitative method for waveform display; the quantitative TG-950P (P905) shown here was already discontinued.

 

 

What you should know about fully-quantitative type miniaturized mainstream CO2 sensors

The TG-907P CO2 Sensor kit (order code P909) shown in above table is declared using quantitative method. This sensor was designed for non-intubated adult CO2 monitoring, as well as neonatal CO2 monitoring. Nihon Kohden is thus offering an alternative to sidestream CO2 sampling methodology.

 

The miniaturized CO2 sensor is easily broken by the bigger and stronger adapter

 

The model using non-coded measurement cable for use by the SVM-7000 series monitors is shown below.

 

TG-971T4 quantitative CO2 sensor kit for SVM-7000 series monitors

In addition to the dead space problem, they had not foreseen miniaturized mainstream CO2 sensors could be easily broken by the disposable adapters. This happened because the disposable adapters are now relatively bigger and stronger!

These are common defects of a TG-970P CO2 sensor kit (P909). The design is impractical.

 

The fragile miniaturized CO2 sensor are clearly of poor design, and easily broken

 

The key point is, it does not last

 

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