Robust Control of Intracranial Pressure with an Electromechanical Extra-ventricular Drainage

The drainage control of cerebrosprinal fluid, as needed in the treatment of increased intracranial pressure, is to this day achieved manually by using an external ventricular drainage system. The manual control procedure bears several risks for the patient among which the rapid decrease of intracranial pressure induced by patient´s upper body inclination angle change is the most prominent. An automatic controller is suggested to increase patient´s safety and the quality of the therapy by delivering a continuous pressure control and the rejection of disturbances like cerebrospinal fluid production rate and inclination angle changes. In this contribution an intracranial pressure controller is designed using the robust control methodology and subsequently validated in nonlinear simulations and in a hydrodynamic human cerebral simulator. The controller is designed using a mixed uncertainty approach accounting for uncertainties in the technical and the physiological system. A self-scheduled implementation of the controller guarantees the compensation of the nonlinear input function for the process, being of Hammer stein structure. The controller shows stable response in simulations and Mock experiments for various operating points and disturbance rejection tests.