METHOD AND DEVICE FOR INTRAOPERATIVE DETERMINATION OF DRAG COEFFICIENT VALUES OF DIFFERENT MEDICAL INSTRUMENTS IN THE USE OF A MEDICAL FLUID PUMP

Abstract

Subject matter of the present invention is a method for determining the resistance coefficients in particular of different combinations of shaft and endoscope when using a medical fluid pump, e.g. in the context of arthroscopy.

Claims

1. A method for determining and controlling the internal body pressure in medical methods, wherein a fluid is pumped by a controllable pumping device through a feed line into a body cavity, wherein the feed line contains, at its patient's end, an exchangeable medical instrument, through which the feed of the fluid into the body cavity takes place, wherein the fluid can flow out of the body cavity through at least one second line, wherein the pump included in the pumping device is controlled, wherein at least the feed line contains a pressure sensor that measures the pressure in the line, wherein the pressure measured by the pressure sensor is an input variable of a mathematical estimation system, which mathematically describes a state space, which estimates the actual pressure in the body cavity and controls the output of the pump by means of this estimated value, wherein the resistance coefficients 1 and 2 of the medical instrument required for the estimation of the pressure are determined by that when starting the pump, the pressure behavior is evaluated for a certain time, therefrom a characteristic curve is determined, and the characteristic curve is stored in a memory device of the pump.

2. The method of claim 1, wherein determining the resistance coefficients 1 and 2 takes place by starting the pump twice.

3. The method of claim 1, wherein determining the resistance coefficients 1 and 2 of the medical instrument takes place pre- or intraoperatively.

4. The method of claim 1, wherein the mathematical estimation system is configured in the manner of a Kalman filter.

5. The method of claim 1, wherein the fluid is a gas or a liquid.

6. A medical apparatus for supplying fluids into body cavities, including a controllable fluid pump, a memory device, a feed line, a pressure sensor in the feed line, a medical instrument to be connected to the feed line, wherein the pressure measured by the pressure sensor is an input variable of a mathematical estimation system, which mathematically describes a state space, which estimates the actual pressure in the body cavity and controls the output of the pump by means of this estimated value, wherein the resistance coefficients 1 and 2 of the medical instrument required for the estimation of the pressure are determined by that when starting the pump, the pressure behavior is evaluated for a certain time, therefrom a characteristic curve is determined, and the characteristic curve is stored in a memory device of the pump.

7. A medical apparatus for supplying fluids into body cavities, including a controllable fluid pump, a memory device, a feed line, a pressure sensor in the feed line, a medical instrument to be connected to the feed line, wherein the pressure measured by the pressure sensor is an input variable of a mathematical estimation system, which mathematically describes a state space, which estimates the actual pressure in the body cavity and controls the output of the pump by means of this estimated value, wherein the resistance coefficients 1 and 2 of the medical instrument required for the estimation of the pressure are determined by that when starting the pump, the pressure behavior is evaluated for a certain time, therefrom a characteristic curve is determined, and the characteristic curve is stored in a memory device of the pump wherein at least one microprocessor, at least one memory and at least one software, which are configured to carry out the method of claim 1.

8. The medical apparatus of claim 6, wherein at least one memory contains data with the resistance coefficients of at least one instrument characteristic curve.

9. The medical apparatus for supplying fluids into body cavities of claim 6, wherein the apparatus is an insufflator.

10. The medical apparatus for supplying fluids into body cavities of claim 6, wherein the apparatus is a liquid pump for arthroscopy, urology, hysteroscopy, laparoscopy, or for examinations of the backbone.

11. The medical apparatus for supplying fluids into body cavities of claim 6, wherein the apparatus is a liquid pump with integrated conveyer and suction pump.

Description

IMPROVEMENTS ACCORDING TO THE INVENTION

[0056] An improvement of the apparatus according to the invention is that the resistance coefficients of every instrument are stored on the instrument itself or can be determined by means of the latter. Thus, for example, it is conceivable to attach a transponder at every instrument, which contains data. By a corresponding transceiver at the pump, these data can be read. The data of the instrument can immediately include the resistance coefficients. Alternatively, they may also be identification data, by means of which the resistance coefficients can be retrieved, e.g., from the pump manufacturer via the internet. Furthermore, alternatively, the data can also be stored on other media, e.g., on barcodes that can be designed in a multi-dimensional manner, or magnetic tapes.