Category: Patient Safety in a Monitoring Network, BSM-3000 series, BSM-6000 series, BSM-1700 series, Life Scope G9 etc.
In this record we reviewed the often-avoided discussion of electrical safety for patients using NIHON KOHDEN (日本光電) Life Scope Patient Monitors for hardwired monitoring.
In this record we reviewed the often-avoided discussion of electrical safety for patients using NIHON KOHDEN (日本光電) Life Scope Patient Monitors for hardwired monitoring.
It is mandatory for hospitals to use network isolation units to ensure electrical safety of monitored patients in a NIHON KOHDEN patient monitoring network
When linking a NIHON KOHDEN Life Scope bedside patient monitor to a network by wire, it is important to pay full and undivided attention to the need for patient electrical safety. NIHON KOHDEN typically does not isolate a monitor's Ethernet port, it is thus imperative hospitals ensure network isolation units are actually installed for sake of patient safety from electrical shocks.
The models that use non-isolated Ethernet port includes Life Scope G9 (CSM-1901), PVM-2700 series (VISMO), BSM-6000 series (Life Scope TR), BSM-3000 series (Life Scope VS), and BSM-1700 series (Life Scope PT) etc. The length of current Nihon Kohden Network Isolator is 86mm long.
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| Example of Life Scope
patient monitors that require the use of network isolation units to ensure patient electrical safety |
The models that use non-isolated Ethernet port includes Life Scope G9 (CSM-1901), PVM-2700 series (VISMO), BSM-6000 series (Life Scope TR), BSM-3000 series (Life Scope VS), and BSM-1700 series (Life Scope PT) etc. The length of current Nihon Kohden Network Isolator is 86mm long.
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| 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 the monitored patient through the wired Ethernet network. Such dangerous electric shocks are potentially lethal and should not be ignored.
The Ethernet switches, routers, network printers and gateway servers are commonly not powered by isolated AC Power and therefore leakage current that cannot pass through the isolated supply of the patient monitor can go to ground through the network. Voltage differences causing electric shock can also arise as a result of incorrect installations or damaged cables on the network. It is recommended by the manufacturer to have the network isolation unit installed within the patient environment.
Note the isolation unit can still be ignorantly removed or bypassed after proper installations if there are no physical measures to make sure this does not happen by accident, and will unknowingly expose the patients to electrical shock risk. Without doubt, the best approach is to have it built into the monitor.
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| The absence of internal built-in network isolation unit clearly confirmed by documents from the manufacturer |
Below is a system composition block diagram showing the connection of LIFE SCOPE VS (BSM-3000 series) patient monitors to a Central Monitor.
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| Network Isolation Unit is shown needed between BSM-3000 series patient monitors and CNS Central Monitor |
The VISMO PVM-2701 and PVM-2703 Patient Monitors has a network card option which also needs the Network Isolation Unit for patient safety.
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| VISMO PVM-2700 series Patient Monitors need the Network Isolation Unit for patient electrical safety |
A few older models namely BSM-1100 series, BSM-2300 series, BSM-4100 series and BSM-5100 series do not have RJ-45 sockets on the patient monitors but instead uses third-party PCMCIA Ethernet Adapter card for Ethernet connectivity. It is not necessary to use a Network Isolation Unit if the connection is via the PCMCIA interface (as shown in below picture) since this is already internally isolated; such interface card is no longer available in the market.
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| Life Scope BSM-4100 series with third-party QI-101P PCMCIA Ethernet Adapter card inserted |
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| The QI-101P PCMCIA network Card is internally isolated |