Three reasons for on-line remote telemonitoring of patients treated with high doses of radionuclide therapy. Our experience.

OBJECTIVE: Following radionuclide therapy, patients usually must remain hospitalised in special "restricted access area" 2-5 days, until radiation in their body drops below a certain level. During this period medical personnel can be faced with some challenges. Based on our previous experience, we used telemedicine approach as solution for it. We have developed comprehensive telemedicine system, which consists of three own developed hardware & software modules which are accessible remotely.

SUBJECTS AND METHODS: Challenge #1 Some of patients can experiencing serious complications related to radionuclide therapy or related to co-morbidities, if they have any of it. In some of those cases audio-visual contact with patients and follow-up their vital functions can be of high importance in case of patient needs urgent intervention. Solution #1 System for on-line remote monitoring of patients' vital functions registered with bed side monitor and video surveillance of area which use patients during hospitalisation. This system is established by IP cameras and bedside patient monitor, equipped with appropriate network card and software. Using remote connection (LAN or internet), a physician can watch at personal computer or mobile phone the waves and vital signs patterns from the bedside monitor, as well as live video from surveillance cameras. It provides prompt intervention in case of emergency. Challenge #2 Having in mind the overall costs of radionuclide therapy and patients hospital stay on the one hand, and limited capacity of the hospital premises for radionuclide therapy, on the other, it is of high importance to estimate as early as possible the time period after which the radiation in a patient's body will drop below the limit imposed by the law. Solution #2 On-line remote radiation monitoring system, which measures the radiation exposure rate by means of a pancake probe, which is connected to a PTZ (Pan-tilt-zoom) device and DVR (Digital video recorder). Those devices enable precise positioning of the detector on target region of the patient's body. The positioning of the detector can be visually controlled by a micro camera, placed at the center of detector's plane. Furthermore, there are three LASER pointers placed around the detector in order to mark the area where it is directed. In addition, two ultrasound sensors placed on the edge of the detector holder in order to estimate the exact distance between the probe and the patient's body. All those devices are controlled by the DVR. The data collected by the detector are acquired and processed by a PC, using customized hardware/software system developed by Italian ThereminoR group. Using remote connection, a physician can watch on-line radiation exposure rate in any time and can use commands of PTZ and DVR device for proper positioning of probe during measurement and control it by micro camera, LASER pointers and US sensors. Physician demands from the patients to take the same position for 5 minutes on each hour, during first 10 hours. Those data we use as reference points for further processing by our software. Based on two exponential matematical model, our software estimates the whole process of elimination of radioactivity from the patient's body, using reference points collected during the first day after radionuclide therapy. Based on that, physician can predict (on first day after therapy!) when patient will be able to leave the restricted access area". Challenge #3 Despite strict instructions given to them by physician and nurse before administration of radionuclide therapy, some patients sometimes try to leave "restricted access area". Solution #3 We have developed a system which continuously monitors the corridor which a patient must use in case of an attempt to leave the "restricted access area". Our system consists of a survey meter equipped with pancake probe directed towards the corridor. The survey meter is connected to a trigger circuit which gives signal in the case when the measeured count rate exceeds previously adjusted value. Trigger circuit is connected to the programmable siren, blinking light, alarm device unit with SIM card and IP surveillance camera. On the siren we previously recorded the voice alarm. In the case when the system is triggered, the patient will hear warning message and see blinking light. When the alarm device is triggered it will call responsible physician and nurse on mobile phone and IP camera simultaneously records this event. System also sending via email appropriate data about each event, when it happens.

CONCLUSION: From our experience gained over the past 4 years, our telemonitoring system dedicated for patients receiving radionuclide therapy ensures a high level of safety for the patient and medical staff.