What Is the Range of Wireless Heart Monitors?

A wireless monitor is a portable transmitter that continuously records the heart rhythm of a patient and transmits this data to a receiver. It is not wired to a bedside monitor. This allows the patient to move freely.

History

• Telemetry devices are a NASA spin-off.

  Telemetry was developed in 1958 by NASA, and others, as a way to send uninterrupted data back to mission control. This included astronaut's vital signs. Wireless cardiac monitoring is a spin-off of space technology.

Significance

• Telemetry uses specific radio frequencies to transmit and receive data.

  Telemetry is a radio signal within an assigned frequency range. The wireless monitor uses telemetry to transmit its data.

How it Works

• A bulky bedside monitor system.

  Powered by batteries, the monitor is connected to a patient by adhesive patches. The monitor records patient data and transmits. The signal is captured by an antenna located in the medical unit. The signal is sent to the central receiver in the nurses' station. The patient's data is then displayed on a monitor screen.

Limitations

• Batteries are the biggest expense for wireless monitor use.

  The transmitting range of a wireless monitor is dependent on several factors, including battery condition, antenna placement and building construction. Even the type of paint on the walls affects the range.

Range

• NASA telemetry, with its greater power, can monitor orbiting astronauts.

  Technicians with the Cleveland Clinic Health System, Clinical Engineering Department, state that with optimal conditions a wireless monitor can transmit up to 100 feet from the nearest antenna.