A medical injection system includes a needle guard and an automatic injection system. The tool includes an intensity modulated pump beam for periodically exciting the sample. The receiver tube is configured to attach to a hitch of a vehicle, such as a pick-up truck. The cladding part is formed as a one piece body with edge areas that at least partially enclose the metal body is firmly secured to the metal body by means of tension applied by the edge areas onto the metal body. An analyzer determines an electrode temperature based on the detector output and predetermined spectrum versus temperature calibration data. The common suction line joined to the endoscope line and the drain bag line draws a flow through the endoscope that predominates, to maintain substantially constant withdrawal of irrigation fluid via that path, and substantially eliminates the possibility of loss of suction.