A medical device, comprising: a cooling system for cooling a patient during a patient cooling procedure； a monitoring device comprising an accelerometer arranged to monitor the chills of the patient during said patient cooling procedure and to provide a monitoring signal that responds thereto, wherein said monitoring device can selectively interconnect to and disconnect from a patient, wherein said monitoring device can be maintained in a fixed relationship with said patient during interconnection, and wherein said monitoring signal is indicative of acceleration as a function of time and comprises a stream of data sets； a processor programmed to process said monitoring signal that uses frequency domain processing to provide an output signal indicative of a magnitude of chills of the patient, wherein said process of frames of said partially overlapping data sets they are processed to obtain and analyze spectral data sets that correspond to a plurality of predetermined frequency bands； an output device arranged to employ the output signal to provide a visual output to a user during said patient cooling procedure in a user interface that responds to said monitoring signal, said visual output being indicative of at least one measure of said chills of the patient and comprising patient movement data displayed in relation to a predetermined scale of magnitude as a function of time.Un aparato médico, que comprende: un sistema de enfriamiento para el enfriamiento de un paciente durante un procedimiento de enfriamiento del paciente； un dispositivo de monitorización que comprende un acelerómetro dispuesto para monitorizar los escalofríos del paciente durante dicho procedimiento de enfriamiento del paciente y para proporcionar una señal de monitorización que responde al mismo, en el que dicho dispositivo de monitorización puede selectivamente interconectarse a y desconectarse de un paciente, en el que dicho dispositivo de monitorización puede mantenerse en una relación fija co
