This article discusses the use of Bluetooth® technology in the Nox PSG system, which allows for wireless transmission of data from the patient to the PC. The article emphasizes the importance of ensuring a clear path for the Bluetooth signal and provides tips for optimising the Bluetooth connection between the Nox A1s and Nox C1 devices.
- Place the Nox C1 close to the Nox A1s
- Place the Nox C1 to have a clear line of sight to the Nox A1s with no physical obstructions
The article also highlights the benefits of using Bluetooth technology, including greater patient comfort and easier cable management for technicians.
Using Bluetooth® technology in the sleep-lab
The reason the Nox PSG equipment looks so futuristic is that it uses Bluetooth technology to wirelessly transmit the patient’s biopotentials through an access point to the PC you’re working on. The benefits of this wireless transmission are comfort for the patient, faster set-ups, easier cable management, and quicker clean-ups for the technician. But, it also requires the technician to think differently about how to support and maintain the data transfer from the patient to the workstation. The most important aspect is to ensure a clear path for the transmission of the Bluetooth signal.
Let’s take a step back and look at the technology used in the Nox PSG system. In a traditional PSG system, the biopotentials would flow from the patient, through the electrodes to the amplifier box, where they would be converted from analog to digital and sent to the PC to be displayed by the software. This is all done with wires. If something goes wrong, you have a wire to investigate (which makes fixing issues with older PSG systems sound much easier than in reality).
On the other hand, the Nox A1s collects the biopotentials and converts them to a digital signal on the device. This digital signal is sent via Bluetooth wirelessly to the Nox C1 Access Point (receiver) in the room. The Nox C1 Access Point is what connects the Nox A1s to the network and allows all the signals to be displayed on the PC via the Noxturnal software. Instead of long, tedious wires, Nox uses a wireless connection between the patient and the software. It’s almost magic. It allows the patient freedom of movement and comfort that is foreign to how we perceive most PSG systems.
Tip from the field: at the hospital I worked in, patients undergoing a diagnostic PSG that had no cables connecting them to a device e.g. TcCO2 or CPAP, and were ambulatory were allowed to just get up and go to the toilet throughout the night. No nurse calls and minutes spent untangling wires. Just up to the toilet and back to sleep without an issue.
This means instead of playing around with cables, the technician needs to make sure that the Bluetooth connection between the Nox A1s and Nox C1 is optimal The following are steps to take both before and during the study to ensure the Bluetooth connection and transmission between the Nox A1s and Nox C1 is optimal:
- Make sure that the Nox A1s and Nox C1 have the latest firmware
- Make sure that both the Nox A1s and Nox C1 are within close proximity. Make sure the devices are as close together as possible (see optimal placement section).
- Remove any physical obstructions that may be interfering with the signal transmission. Do not put the Nox C1 far away from the patient or place it in a cupboard. Ideally, place it on top of a bedside table next to the bed.
- Prevent bedding material such as blankets and clothing from the patient such as thick clothing from disrupting the signal. Ideally, the Nox A1s and the Nox RIP belts should be placed on top of a thin shirt.
Nox A1s and Nox C1 Optimal Placement
For users with the Nox A1s, the position of the Bluetooth® dongle connected to the Nox C1 is important. If your study features gaps in playback or slow data transfer, the first step will be to reposition the Nox C1 in relation to the patient. The best position is close to the patient with a clear line for the Bluetooth connection between the Nox A1s and the Nox C1. Feedback from the field suggests having a Nox C1 on a bedside table with dongle facing away from the Nox A1s (see image below). It is important to adapt the set up the environment. With recent versions of the Nox A1s firmware, you can check the signal strength of the Bluetooth connection and adjust the position of the Nox C1 in relation to the Nox A1s to achieve the best connection for the setup you are using.
This image provides a bird's eye view of the patient and Nox A1s and Nox C1 set-up. The Nox C1 is set up on the right hand side on a bedside table with the Bluetooth dongle facing away from the Nox A1s.