Irreversible electroporation to control bleeding

Abstract

A method of stopping or controlling bleeding by the placement of electrodes into or near the vicinity of vessels is disclosed. Then the application of electrical pulses causing irreversible electroporation of vessel and blood cells throughout the entire area of current flow the bleeding is stopped or controlled. The electric pulses irreversibly permeate the cell membranes, thereby invoking cell death. The irreversibly permeabilized cells are left in situ and are removed by the body immune system. Through the use of irreversible electroporation bleeding can be stopped or controlled without inducing thermal damage.

Description

CROSS-REFERENCE [0001] This application claims the benefit of U.S. Provisional Application No. 60 / 532,588, filed Dec. 24. 2003, which application is incorporated herein by reference.FIELD OF THE INVENTION [0002] This invention resides in the fields of electroporation of tissue and to treatments whereby unwanted bleeding is stopped. BACKGROUND OF THE INVENTION [0003] In many medical procedures, such as the treatment of benign or malignant tumors, it is important to be able to ablate the undesirable tissue in a controlled and focused way without affecting the surrounding desirable tissue. Over the years, a large number of minimally invasive methods have been developed to selectively destroy specific areas of undesirable tissues as an alternative to resection surgery. There are a variety of techniques with specific advantages and disadvantages, which are indicated and contraindicated for various applications. For example, cryosurgery is a low temperature minimally invasive technique in...

AI Technical Summary

Benefits of technology

[0020] The present invention comprises a method whereby blood flow and such bleeding from a vessel is stopped with the application of electrical pulses causing irreversible electroporation of cells making up vessels and blood involved in unwanted bleeding. The electric pulses irreversibly permeate the membranes, thereby invoking cell death. The length of time of the electrical pulses, the voltage applied and the resulting membrane permeability are all controlled within defined ranges. The irreversibly permeabilized cells may be left in situ and may be removed by natural processes such as the body's own immune system. Through the use of irreversible electroporation bleeding may be completely disrupted or controlled without inducing thermal damage.

[0026] The invention provides the simultaneous irreversible electroporation of multitudes of cells providing a direct indication of the actual occurrence of electroporation and an indication of the degree of electroporation averaged over the multitude. The discovery is likewise useful in the irreversible electroporation of biological tissue (masses of biological cells with contiguous membranes) for the same reasons. The benefits of this process include a high level of control over the beginning point of irreversible electroporation.

[0027] A feature of the invention is that the magnitude of electrical current during electroporation of the tissue becomes dependent on the degree of electroporation so that current and pulse length are adjusted within a range predetermined to obtain irreversible electroporation of targeted cells of the tissue while minimizing cellular damage to surrounding cells and tissue.

[0028] An aspect of the invention is that pulse length and current are precisely adjusted within ranges to provide more than mere intracellular elecctro-manipulation which results in cell death and less than that which would cause thermal damages to the surrounding tissues.

Problems solved by technology

The electroporation pulse should not have considerable thermal effects, but irreversible break cell membranes of targeted cells and result in cell death.

Of these effects, irreversible electroporation is generally undesirable due to the possibility of instantaneous necrosis of the entire tissue affected by the electrical field, regardless of its diseased or healthy state.

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