Abstract: Revolutionizing Remote Monitoring of Free Flaps with Laser Doppler Flowmetry and Smart Devices

Abstract

PURPOSE: The purpose of this presentation is to demonstrate an innovative method for remote free flap monitoring using laser Doppler flowmetry and smart devices. INTRODUCTION: Newer generation of free flap monitoring device using tissue oximetry offers web-based capability for transmission of recordings to the smart phone. However, remote monitoring capability does not currently exist for the Perimed laser Doppler (Perimed AB, Järfälla, Sweden) when used without connection to a computer. Using an existing tablet and a free app (application), the smart device can be converted into a Wi-Fi camera, which can be placed adjacent to the laser Doppler monitor to allow instant, real-time monitoring remotely. Multiple apps are currently available which can convert a smart phone or tablet (e.g. iPad) into a remote camera, which can then be linked to the provider’s smartphone over the internet. METHODS: We present our preliminary experience with this smart device app to a well-established modality, laser Doppler flowmetry,1,2 for monitoring free flaps. We employed the AtHome app from the app store which converted a used iPad into a camera and multiple smart phones into independent viewers. No patient identifier was transmitted with this remote monitoring set-up. RESULTS: We monitored 9 head and neck free flaps, each for 4–6 days remotely with near 100% reliability. We had minor mechanical issues: capturing angle of smart device getting displaced; device getting knocked off the table; and charge cord dislodging. Auto-lock needs to be turned off on the capturing smart device. On one occasion, the camera app needed restarting due to automatic software update. These glitches were each corrected by a phone call to the nurse or by the provider in person. For one flap, nursing over-sedated the patient leading to profound hypotension. The steady decline in the laser Doppler reading witnessed by the surgeon remotely allowed him the opportunity to rapidly return to the ICU to resuscitate the patient, thus avoiding anastomotic thrombosis from hypoperfusion. CONCLUSION: Remote monitoring of the laser Doppler readings by multiple providers on the team for all 9 flaps was successful for the duration of 4–6 days. The ability to remotely look at your patient’s laser Doppler numbers (or recordings from any monitoring modality) in real-time can be provided by a simple, inexpensive, and reliable adaptation of smart device and app technology. Reference Citations: 1. Bellamy JL, Mundinger GS, Flores JM, et al. Do adjunctive flap-monitoring technologies impact clinical decision making? An analysis of microsurgeon preferences and behavior by body region. Plast Reconstr Surg 135:883, 2015. 2. Yuen JC, Feng Z. Monitoring free flaps using the laser Doppler flowmeter: five-year experience. Plast Reconstr Surg 105:55, 2000.