| 摘要 |
Vibration is conveyed to the proximal orifices of an indwelling catheter to disintegrate accumulated clogging deposits, large suspended particles and contaminating bacteria, viruses, fungi, etc. Orifices may be recessed, hooded or enclosed, and in some cases the catheter tip should be of absorptive material, to deter propagation of the vibration to the parts of the patient's body outside the catheter. Vibration may be conveyed to the orifices by (1) a solid fiber embedded in the catheter walls or positioned in an auxiliary lumen of the catheter; or (2) by a liquid in an auxiliary lumen-which may be formed as an annular space surrounding the main lumen. Preferably the apparatus measures the amount of vibration absorbed by the deposits or bacteria, etc., as a function of frequency, and automatically concentrates the vibration at frequencies where absorption is particularly high, to maximize the disintegration of deposits, particles, bacteria or other bioactive objects. Ultrasonic shear waves are thought more effective than compressional waves, but both may be used. |
