Practical Guide for Effective Radio Wave Management in Medical Telemetry Devices, covering the following major topics:

 

1. Background

• Current issues

According to a 2024 survey, about 40% (36.8%) of hospitals using medical telemetry have experienced radio wave troubles. The most common cause (79.2%) was "areas where radio signals could not reach sufficiently" (dead zones).

• Causes of troubles

Dead zones are often caused by difficulties in antenna cabling (such as concrete beams or firewalls), aging antenna systems (approximately 70% have been in use for over 10 years), human errors (e.g., incorrect channel settings, battery depletion), and electromagnetic noise or interference from other devices and equipment.

 

2. Main Practices for Target groups

• Nurses

As the first to detect problems, it is recommended that nurses confirm abnormalities (such as signal loss or waveform distortion) and accurately report information, including location, channel, and patient condition, to clinical engineers or radio management personnel. They also respond promptly to issues like battery depletion or detached electrodes.

• Clinical engineers

As those responsible for wireless channel management, it is important to perform channel management, zone layout, and regular inspections. Based on reports from nurses, they shall identify dead zones and check the received signal strength (C/N ratio of 30 dB or higher is recommended) using simple spectrum analyzer function.

• Medical Administrative staffs

It is desirable to establish a hospital-wide, cross-departmental radio wave management system, promote renewal plans for aging antenna systems, and instruct architects or contractors to follow "construction guidelines" during new construction or renovation projects.

 

3. Examples of dead zone countermeasures

In the FY 2023 survey, hospitals that implemented dead zone countermeasures reported improvements.

• When antennas were located in unsuitable places such as corridors or room entrances, relocating or adding antennas near the center of patient rooms significantly improved signal strength (C/N improved by 15-54 dB), effectively eliminating signal loss.
• In areas with large signal fluctuations, introducing a diversity reception system using multiple antennas proved effective. Additionally, optimizing the placement of amplifiers (boosters) and restoring power to inactive boosters also led to improvements.

The practical guide provides more details and suggestions for medical institutions and healthcare staffs to take into consideration.

 

Connect with us today to ensure your devices operate safely, efficiently, and in full compliance with Japanese regulations.

 

Reference

Practical guide for radio wave management of medical telemetry devices