Artificial Diuresis: animal studies on efficacy and safety of a new miniaturized device for extracorporeal ultrafiltration

Introduction. We have recently developed a new miniaturized device for extracorporeal ultrafiltration to be used in patients with fluid overload: Artificial Diuresis-1, or AD1 (Medica S.p.A., Medolla, Italy). The device has a reduced priming volume and operates at very low pressure and flow regimes and is designed to perform extracorporeal UF at bedside. After accurate experiments carried out in vitro, we report in this paper the results of in vivo tests ultrafiltration session carried out in selected animals according to veterinary best practice. Materials and methods. The AD1 kit is pre-filled with sterile isotonic solution and operates with a polysulfone mini-filter MediSulfone (Polysulfone at 50000 Dalton). A collection bag with a volumetric scale is connected to the UF line and the ultrafiltrate is obtained by gravity based on the height at which the ultrafiltrate collection bag is placed. Animals were prepared and anesthetized. Jugular vein was cannulated with a double lumen catheter. Three six hours sessions of ultrafiltration were scheduled with a target fluid removal of 1500 ml. Heparin was used as anticoagulant.Results. In all treatments the target value of ultrafiltration was obtained in the absence of major clinical or technical problems with a maximum deviation from the scheduled ultrafiltration rate lower than 10%. The device resulted safe, reliable, accurate and easily usable thanks to a user friendly interface and the very small dimensions. Conclusions. This study opens the way for clinical trials in different settings including departments with low intensity of care and even in ambulatory centers or patient's home.