A Study on Catheter Drives for Automatic Aspiration Working with Ventilator

We developed a catheter drive with two rotors that pinch an aspiration catheter between them and incline along the perpendicular of the catheter axis at mutually opposite angles. Rotors are driven with the same torque in opposite directions to minimize residual torque devolving on the patient being treated. The catheter drive enables a flexible 4 mm diameter plastic catheter to be inserted into and withdrawn from a respiratory cannula over 200 mm long at a constant speed of 30 mm/s accompanying catheter rotation. The catheter drive is about 30 g mass, including a joint to a ventilator and a joint to a vacuum resource for aspiration. Aspiration tests of 5 types of dummy sputum confirmed the feasibility of aspiration by the catheter drive we developed.