The distance between ring 118 and skirt 119 as skirt 119 reciprocates in response to the magnetic field generated by magnetic ring assembly 76′″ as described in further detail below, is minimized to reduce leakage of blood between delivery channels 100 a″ and 100 b″, and to reduce blood damage. As magnetic ring assembly 76′ moves up and down, the movement is rigidly translated by posts 81′ to J-shape of skirt 115 of membrane assembly 82′. Given the rigidity of the posts, when magnetic ring assembly 76′ travels a certain distance upward or downward, membrane assembly 82′ may travel the same distance.
- Competencias de los profesionales de Enfermería
- Inflamación de uno de los testículos o ambos (orquitis)
- Epidemiología de los síndromes dolorosos
- Terapia sistémica
- Dolor crónico neuropático periférico
- Enfermedades coronarias o cardiovasculares
Similarly, the frequency at which magnetic ring assembly 76′″ traverses the space between the first and second electromagnetic coils may be the same frequency at which membrane assembly 82′″ travels the same distance. Along with the frequency and amplitude, the duty cycle, defined by the percentage of time membrane 97 is excited over a set period of time, may be adjusted to achieve a desired flow output and pulsatility, without loss of pump efficiency.
As duty cycle and frequency operate independent of one another, duty cycle may be manipulated between 0 and 100% while leaving the frequency of 120 Hz unaffected. Similarly, the controller may determine that current output exceeds demand and thus alter output by changing frequency, amplitude and/or duty cycle. Specifically, from the current measurement, the controller is able to control the excitation of the deformable membrane, e.g., membrane 97, while being robust to the almost un-modelled force of the deformable membrane Fmembrane. SUMMARY OF THE INVENTION The present invention overcomes the drawbacks of previously-known LVAD systems and methods by providing an implantable pump system having an undulating membrane capable of producing a wide range of physiological flow rates while applying low shear forces to the blood, thereby reducing hemolysis and platelet activation relative to previously-known systems. Previously-known reciprocating pump LVADs have a number of drawbacks. The implantable blood pump system further may include a rechargeable battery for delivering the alternating current to power the implantable blood pump.
Tipos De Dolor Dental
Battery 40 may include a separate charging circuit, not shown, as is conventional for rechargeable batteries. Alternatively, or in addition, battery 40 may include port 47 which may be removably coupled to a transformer and cable to permit the battery to be recharged using a conventional residential power outlet, e.g., 120 V, 60 Hz AC power. 16B illustrates blood flow using a pump assembly with a skirt in accordance with one aspect of the present invention.
Tecnicas De Relajacion
Implantable pump 20′″ is constructed similar to implantable pump 20′ described in FIGS. The sensors preferably are in electrical communication with controller 30, and may monitor operational parameters that measure the performance of implantable pump 20 or physiological sensors that measure physiological parameters of the patients such as heart rate or blood pressure. As such, height of skirt 115 is preferably at least 2 mm, and more preferably at least 4 mm, at least 10 mm, and/or at least 18 mm. 18, an alternative exemplary embodiment of the pump assembly of the present invention having a J-shaped skirt is described.
3A, controller 30 further includes microprocessor 38, memory 39, battery 43, optional transceiver 44 and amplifier circuitry 45. Microprocessor may be a general purpose microprocessor, for which programming to control operation of implantable pump 20 is stored in memory 39. Memory 39 also may store configuration settings and operational parameters for implantable pump 20. Battery 40 supplies power to controller 30 to provide continuity of operation when battery 40 is periodically swapped out. Ansiedad y dolor de espalda . Optional transceiver 44 to facilitates wireless communication with programmer 50 and/or mobile device 60 via any of a number of well-known communications standards, including BLUETOOTH™, ZigBee, and/or any IEEE 802.11 wireless standard such as Wi-Fi or Wi-Fi Direct.
See, e.g., P. Mercorelli, A Motion-Sensorless Control for Intake Valves in Combustion Engines, IEEE Transactions on Industrial Electronics, vol. Skirt 115 exhibits rigid properties under typical forces experienced during the full range of operation of the present invention and may be made of a biocompatible metal, e.g., titanium. First suspension ring 79 and second suspension ring 80 may comprise stainless steel having elastic properties and which exhibits a spring force when deflected in a direction normal to the plane of the spring. Because magnetic ring assembly 76 may be rigidly affixed to posts 81, which in turn may be rigidly affixed to first suspension ring 79 and second suspension ring 80, the elastic properties of the suspension rings permit magnetic ring assembly 76 to move up towards first electromagnetic coil 77 or downward toward second electromagnetic coil 78, depending upon the polarity of magnetic fields generated by the electromagnetic rings.
As explained above, membrane assembly 82 may be suspended by posts 81 within flow channel 101 below the bottom surface of flanged portion 87 and above the interior surface of lower housing portion 25. Membrane assembly 82 may be free to move up and down in the vertical direction within flow channel 101, which movement is constrained only by suspension rings 79 and 80. Membrane assembly 82 may be constrained from twisting, tilting or moving in any direction in flow channel 101 other than up and down by rigid posts 81 and by the suspension rings.
Dolor De Hombro
In this manner, first suspension ring 79 and second suspension ring 80 may exhibit a spring tension when deformed up and down relative to a vertical axis of the actuator assembly but may rigidly resist movement along any other axis, e.g., tilt or twist movements. As a yet further alternative, membrane 97 may vary in thickness and exhibit more complex geometries.