Ultra-short pulse defibrillator

Abstract

The present invention belongs to the technical field of medical devices, and specifically relates to a defibrillator. An ultrashort pulse defibrillator includes a DC power supply, an energy storage capacitor, and a pair of electrodes connected in sequence, and also includes: a discharge switch circuit, which is arranged before the energy storage capacitor and the pair of electrodes, and is used to control the discharge time of the energy storage capacitor; a step-up transformer, which is arranged between the discharge switch circuit and the pair of electrodes, and the step-up transformer increases the voltage on the energy storage capacitor to a preset amplitude. The present invention uses nanosecond to microsecond ultrashort pulse electric fields for defibrillation. Due to the pulse action time, less energy is deposited on ventricular cells, which reduces the destructive effect of the defibrillation pulse on myocardial cells, reduces the irreversible electroporation damage to myocardial cells, and also improves the success rate of defibrillation.

Description

Technical Field

[0001] The invention belongs to the technical field of medical devices, and in particular relates to a defibrillator. Background Art

[0002] A cardiac defibrillator is a device that uses electrical pulses to terminate ventricular fibrillation and restore sinus rhythm. As an important medical electronic device for cardioverting malignant arrhythmias such as ventricular fibrillation and ventricular tachycardia, cardiac defibrillators have been widely used in clinical practice. However, the current clinical rescue success rate for such patients is still unsatisfactory. Since its invention in 1962, improving the success rate of defibrillation and reducing the side effects of defibrillation have always been the goal pursued by people.

[0003] Traditional defibrillators use energy to perform defibrillation based on the principle of electrical stimulation of myocardial cells by electric current. The side effects of this type of defibrillator may include increased morbidity and mortality, anxiety, pain, and cell damage. In 1991, biphasic waves were used to replace the monophasic waves that had been used for more than 30 years for defibrillation, which can significantly reduce the defibrillation energy and reduce side effects. The pulse width of the defibrillation waveform currently used in clinical practice is in the millisecond range, that is, the duration of the defibrillation pulse is between 6 and 32ms. According to the myocardial electrical stimulation intensity-action time curve, the energy required for electric shock defibrillation within this pulse width range is the lowest. Millisecond waves should require hundreds of joules of energy. Although millisecond waves can effectively terminate ventricular fibrillation, excessively wide pulses can easily cause irreversible electroporation of myocardial cells, destroying the function of myocardial cells.

[0004] The waveform of ventricular fibrillation on the surface electrocardiogram constantly changes in shape, amplitude and direction. The electrical excitation of the ventricular muscle during ventricular fibrillation is completely random and has no regularity at all. The depolarization waves wander freely in the ventricular wall, changing shape and direction independently. Ventricular fibrillation is described as "violent" or "chaotic."

[0005] According to the principle of electroporation, the pulsed electric field causes nanoscale holes to form on the cell membrane. These holes interrupt the depolarization wave from wandering freely in the ventricular wall, terminating ventricular fibrillation. The pulse width and the number of pulses jointly determine the electroporation results of myocardial cells. If the pulse width is too wide and the number of pulses is too many, irreversible electroporation will occur in myocardial cells, causing irreversible damage to myocardial cells. Summary of the invention

[0006] The present invention aims to provide an ultra-short pulse defibrillator to solve the technical problem that irreversible electroporation and irreversible damage easily occur in existing defibrillators due to the excessively wide pulse width of the defibrillation waveform and the excessive number of times.

[0007] An ultrashort pulse defibrillator comprises a DC power supply, an energy storage capacitor and a pair of electrodes connected in sequence, and further comprises:

[0008] a discharge switch circuit, disposed between the energy storage capacitor and the pair of electrodes, for controlling the discharge time of the energy storage capacitor;

[0009] A step-up transformer is arranged between the discharge switch circuit and a pair of electrodes, and the step-up transformer increases the voltage on the energy storage capacitor to a preset amplitude.

[0010] Before defibrillation, the present invention uses a DC power supply to charge the energy storage capacitor, stores energy in the energy storage capacitor, and determines the voltage condition in the energy storage capacitor according to the voltage amplitude of the output pulse. During defibrillation, the discharge switch circuit works to transfer the energy in the energy storage capacitor to the step-up transformer. The step-up transformer increases the voltage on the energy storage capacitor to a certain amplitude and applies it to the human body through a pair of electrodes. The voltage forms a pulse electric field of 1500V / cm on the human heart, causing electroporation of the myocardial cell membrane and terminating ventricular fibrillation.

[0011] The energy storage capacitor comprises:

[0012] an electrolytic capacitor, a positive electrode of which is connected to the positive electrode of the DC power supply, and a negative electrode of which is connected to the negative electrode of the DC power supply;

[0013] A film capacitor is connected in parallel with the electrolytic capacitor.

[0014] The discharge switch circuit comprises:

[0015] a first MOS tube, the drain of which is connected to the non-same-name end of the boost transformer, and the source of which is connected to the negative electrode of the energy storage capacitor;

[0016] a discharge switch control module, whose signal output end is connected to the gate of the first MOS tube and is used to control the on or off of the first MOS tube;

[0017] The discharge switch control module controls the first MOS tube to be turned on, the energy storage capacitor is connected to the step-up transformer, and a single-phase exponential wave defibrillation pulse with a preset amplitude is generated on the secondary side of the step-up transformer. The discharge time constant τ of the energy storage capacitor is CR, where C is the capacity of the energy storage capacitor, and R is the human body impedance between a pair of electrodes converted to the primary resistance of the step-up transformer.

[0018] The discharge switch circuit further includes:

[0019] A first protection diode, which is a bidirectional voltage regulator, one end of which is connected to the positive electrode of the energy storage capacitor, and the other end of which is connected to the positive electrode of the boost transformer;

[0020] a discharge inductor connected in parallel with the first protection diode;

[0021] The discharge switch control module controls the discharge switch circuit in the following manner:

[0022] Assume that the defibrillation discharge time is t0, the discharge period is t1, and the discharge end time is t2, then:

[0023] At time t0, the first MOS tube is turned on, and the charge in the energy storage capacitor is applied to the primary side of the step-up transformer via the discharge inductor, forming a defibrillation voltage and current on the secondary side of the step-up transformer, and the voltage and current form a pulse electric field between a pair of electrodes;

[0024] During the period from time t0 to time t1, a unipolar defibrillation pulse is outputted at the secondary side of the step-up transformer, and a preset energy is stored in the discharge inductor;

[0025] At time t1, the first MOS tube is disconnected, and a negative wave is generated on the secondary side of the boost transformer, resulting in the formation of a quasi-biphase wave.

[0026] The discharge switch circuit further includes:

[0027] a second MOS tube, the drain of which is connected to the same-name terminal of the primary side of the boost transformer, the source of which is connected to the negative electrode of the energy storage capacitor, and the gate of which is connected to the signal output terminal of the discharge switch control module;

[0028] a second protection diode, which is a bidirectional voltage regulator, one end of which is connected to the positive electrode of the energy storage capacitor, and the other end of which is connected to the drain of the second MOS tube;

[0029] a third protection diode, which is a bidirectional voltage regulator, one end of which is connected to the positive electrode of the energy storage capacitor, and the other end of which is connected to the drain of the first MOS tube;

[0030] The positive electrode of the energy storage capacitor is also connected to the middle tap of the step-up transformer;

[0031] The discharge switch control module controls the discharge switch circuit in the following manner:

[0032] Assume that the defibrillation discharge time is t0, the discharge period is t1 and t2, and the discharge end time is t3, then:

[0033] At time t0, the second MOS transistor is turned on, and the first MOS transistor is turned off. The discharge current flows from the energy storage capacitor through the boost transformer and the second MOS transistor back to the energy storage capacitor. The primary voltage of the boost transformer is equal to the voltage on the energy storage capacitor, and a high-voltage square wave is generated on the secondary side of the boost transformer.

[0034] At time t1, the second MOS transistor is disconnected, and the first MOS transistor is disconnected;

[0035] At time t2, the first MOS transistor is turned on, and the second MOS transistor is turned off, and the discharge current flows back from the energy storage capacitor through the step-up transformer and the first MOS transistor to the energy storage capacitor, and a negative pulse is output on a pair of electrodes;

[0036] At time t3, both the first MOS tube and the second MOS tube are disconnected, and defibrillation ends.

[0037] There are two energy storage capacitors, namely a first energy storage capacitor and a second energy storage capacitor, and a capacitor switch is provided between the positive electrode of the first energy storage capacitor and the positive electrode of the second energy storage capacitor;

[0038] The primary side of the step-up transformer includes two groups of primary coils, namely:

[0039] a first primary coil, wherein the same-name end is connected to the positive electrode of the first energy storage capacitor, and the non-same-name end is connected to the drain of the first MOS transistor;

[0040] a second primary coil, the non-identical end of which is connected to the positive electrode of the second energy storage capacitor;

[0041] The source electrode of the first MOS tube is connected to the negative electrode of the first energy storage capacitor;

[0042] The discharge switch circuit further includes:

[0043] a third MOS tube, wherein the drain is connected to the same-name end of the second primary coil, the source is connected to the negative electrode of the second energy storage capacitor, and the gate is connected to the signal output end of the discharge switch control module;

[0044] a fourth protection diode, which is a bidirectional voltage regulator, one end of which is connected to the positive electrode of the first energy storage capacitor, and the other end of which is connected to the drain of the first MOS tube;

[0045] a fifth protection diode, which is a bidirectional voltage regulator, one end of which is connected to the positive electrode of the second energy storage capacitor, and the other end of which is connected to the drain of the third MOS tube;

[0046] The first energy storage capacitor, the step-up transformer and the first MOS transistor form a discharge loop, and the second energy storage capacitor, the step-up transformer and the third MOS transistor form another discharge loop;

[0047] The discharge switch control module controls the discharge switch circuit in the following manner:

[0048] During defibrillation discharge, the first MOS tube is turned on to release all the charges in the first energy storage capacitor, forming a positive defibrillation pulse on the pair of electrodes, and then the third MOS tube is turned on to release all the charges in the second energy storage capacitor, forming a negative defibrillation pulse on the pair of electrodes. After the negative defibrillation pulse, the defibrillation process ends.

[0049] The discharge switch circuit further includes:

[0050] a fourth MOS tube, whose drain is connected to the positive electrode of the energy storage capacitor, whose source is connected to the non-same-name end of the boost transformer, and whose gate is connected to the signal output end of the discharge switch control module;

[0051] a fifth MOS tube, whose drain is connected to the positive electrode of the energy storage capacitor, whose source is connected to the same-name terminal of the boost transformer, and whose gate is connected to the signal output terminal of the discharge switch control module;

[0052] a sixth MOS tube, wherein the drain is connected to the same-name terminal of the step-up transformer, the source is connected to the negative electrode of the energy storage capacitor, and the gate is connected to the signal output terminal of the discharge switch control module;

[0053] The discharge switch control module controls the discharge switch circuit in the following manner:

[0054] Assume that the defibrillation discharge time is t0, the discharge period is t1 and t2, and the discharge end time is t3, then:

[0055] Before defibrillation, the first MOS tube and the sixth MOS tube are turned on, the fourth MOS tube and the fifth MOS tube are turned off, and both ends of the primary side of the boost transformer are grounded;

[0056] At time t0, the fifth MOS transistor is turned on, the sixth MOS transistor is turned off, the same-name terminal of the primary side of the boost transformer is connected to the positive electrode of the energy storage capacitor, the first MOS transistor is turned on, the fourth MOS transistor is turned off, the non-same-name terminal of the primary side of the boost transformer is connected to the negative electrode of the energy storage capacitor, and a voltage is generated on the secondary side of the boost transformer to form a first phase of the defibrillation waveform, wherein the output waveform of the first phase is a square wave;

[0057] At time t1, the first MOS transistor and the sixth MOS transistor are turned on, the fourth MOS transistor and the fifth MOS transistor are turned off, and both ends of the primary side of the boost transformer are grounded. The primary side input voltage of the boost transformer is zero, so the secondary side voltage of the boost transformer is also zero.

[0058] At time t2, the fifth MOS transistor is disconnected, the sixth MOS transistor is turned on, the same-name terminal of the primary side of the boost transformer is connected to the negative electrode of the energy storage capacitor, the fourth MOS transistor is turned on, the first MOS transistor is disconnected, the non-same-name terminal of the primary side of the boost transformer is connected to the positive electrode of the energy storage capacitor, and a negative voltage is generated on the secondary side of the boost transformer to form the second phase of the defibrillation waveform, and the output waveform of the second phase is a square wave;

[0059] At time t3, the first MOS tube, the fourth MOS tube, the fifth MOS tube and the sixth MOS tube are all disconnected, and the defibrillation ends.

[0060] The positive improvement effect of the present invention is that the present invention adopts an ultra-short pulse defibrillator, which has the following significant advantages:

[0061] 1. Use pulsed electric field to form numerous nano-scale holes on the cell membrane, blocking the ventricular depolarization wave channel in a chaotic state, thus achieving the purpose of defibrillation;

[0062] 2. Defibrillation is performed using nanosecond to microsecond ultra-short pulse electric fields. Due to the pulse action time, less energy is deposited on ventricular cells, which reduces the destructive effect of defibrillation pulses on myocardial cells, reduces irreversible electroporation damage to myocardial cells, and also improves the success rate of defibrillation;

[0063] 3. The step-up transformer is used to output pulses, the voltage of the energy storage capacitor is low, and the patient is electrically isolated from the energy storage capacitor, which improves the safety of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 It is an overall structural block diagram of the present invention;

[0065] Figure 2 A circuit schematic diagram of the first embodiment of the present invention;

[0066] Figure 3 A circuit schematic diagram of the second embodiment of the present invention;

[0067] Figure 4 A circuit schematic diagram of the third embodiment of the present invention;

[0068] Figure 5 A circuit schematic diagram of a fourth embodiment of the present invention;

[0069] Figure 6 This is a circuit schematic diagram of Embodiment 5 of the present invention. DETAILED DESCRIPTION

[0070] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below with reference to specific illustrations.

[0071] Reference Figure 1 , an ultrashort pulse defibrillator, comprising a DC power supply 100, a storage capacitor C (200), a discharge switch circuit 300, a step-up transformer T1 and a pair of electrodes 400 connected in sequence.

[0072] In the present invention, before defibrillation, the DC power supply 100 charges the energy storage capacitor C, stores energy in the energy storage capacitor C, and determines the voltage condition in the energy storage capacitor C according to the voltage amplitude of the output pulse. During defibrillation, the discharge switch circuit 300 works to control the discharge time of the energy storage capacitor C and transfer the energy in the energy storage capacitor C to the step-up transformer T1. The step-up transformer T1 increases the voltage on the energy storage capacitor C to a preset amplitude and applies it to the human body 500 through a pair of electrodes 400. This voltage forms a pulse electric field of 1500V / cm on the human heart, causing electroporation of the myocardial cell membrane and terminating ventricular fibrillation.

[0073] Embodiment 1, refer to Figure 2 This embodiment provides an ultrashort pulse defibrillator, including a DC power supply, an energy storage capacitor 200, a discharge switch circuit, a step-up transformer T1 and a pair of electrodes 400.

[0074] The DC power supply provides electrical energy to the energy storage capacitor. Before defibrillation, the energy is stored in the energy storage capacitor through the DC power supply. The voltage in the energy storage capacitor is determined according to the voltage amplitude of the output pulse. Considering the withstand voltage of each switch tube in the discharge switch circuit, the voltage of the energy storage capacitor should not be too high. Considering the influence of the transformation ratio of the step-up transformer T1, the voltage of the energy storage capacitor should not be too high.

[0075] The energy storage capacitor includes an electrolytic capacitor C1 and a film capacitor C2, wherein the positive electrode of the electrolytic capacitor C1 is connected to the positive electrode of the DC power supply, and the negative electrode of the electrolytic capacitor C1 is connected to the negative electrode of the DC power supply. The film capacitor C2 is connected in parallel with the electrolytic capacitor C1.

[0076] The discharge switch circuit 300 includes a first MOS tube K1 and a discharge switch control module. The drain of the first MOS tube K1 is connected to the non-same-name end of the step-up transformer T1, and the source of the first MOS tube K1 is connected to the negative electrode of the energy storage capacitor 200 and grounded. The signal output end of the discharge switch control module is connected to the gate of the first MOS tube K1, and the discharge switch control module is used to control the conduction or disconnection of the first MOS tube K1.

[0077] The primary like-name end of the boost transformer T1 is connected to the positive electrode of the energy storage capacitor 200 , the secondary like-name end of the boost transformer T1 is connected to one electrode, and the secondary non-like-name end of the boost transformer T1 is connected to the other electrode and grounded.

[0078] The discharge switch control module controls the first MOS tube K1 to be turned on, the energy storage capacitor 200 is connected to the step-up transformer T1, and a single-phase exponential wave defibrillation pulse with a preset amplitude is generated on the secondary side of the step-up transformer T1. The discharge time constant τ of the energy storage capacitor 200 is CR, where C is the capacity of the energy storage capacitor 200, and R is the human body impedance between a pair of electrodes 400 converted to the primary side resistance of the step-up transformer T1. Since the first MOS tube K1 is always kept in the on state during the discharge process, the energy in the energy storage capacitor 200 will be completely released, and the leakage inductance in the step-up transformer T1 will not generate a reverse voltage on the drain of the first MOS tube K1.

[0079] Example 2, refer to Figure 3 This embodiment provides an ultrashort pulse defibrillator, including a DC power supply, an energy storage capacitor 200, a discharge switch circuit 300, a step-up transformer T1 and a pair of electrodes 400.

[0080] The DC power supply provides electric energy to the energy storage capacitor 200. Before defibrillation, the energy is stored in the energy storage capacitor 200 through the DC power supply. The voltage in the energy storage capacitor 200 is determined according to the voltage amplitude of the output pulse. Considering the withstand voltage of each switch tube in the discharge switch circuit, the voltage of the energy storage capacitor 200 should not be too high. Considering the influence of the transformation ratio of the step-up transformer T1, the voltage of the energy storage capacitor 200 should not be too high.

[0081] The energy storage capacitor 200 includes an electrolytic capacitor C1 and a film capacitor C2. The positive electrode of the electrolytic capacitor C1 is connected to the positive electrode of the DC power supply, and the negative electrode of the electrolytic capacitor C1 is connected to the negative electrode of the DC power supply. The film capacitor C2 is connected in parallel with the electrolytic capacitor C1. In actual implementation, the energy storage capacitor 200 is selected to be large enough so that only part of the energy is released during the discharge defibrillation process.

[0082] The discharge switch circuit 300 includes a first MOS tube K1, a discharge switch control module, a first protection diode Z1 and a discharge inductor L. The drain of the first MOS tube K1 is connected to the non-same-name end of the boost transformer T1, and the source of the first MOS tube K1 is connected to the negative electrode of the energy storage capacitor 200 and grounded. The signal output end of the discharge switch control module is connected to the gate of the first MOS tube K1, and the discharge switch control module is used to control the conduction or disconnection of the first MOS tube K1. The first protection diode Z1 is a bidirectional voltage regulator, one end of the first protection diode Z1 is connected to the positive electrode of the energy storage capacitor 200, and the other end of the first protection diode Z1 is connected to the same-name end of the boost transformer T1. The discharge inductor L is connected in parallel with the first protection diode Z1, and the function of the discharge inductor L is to limit the discharge current during the discharge period.

[0083] The secondary like-named end of the step-up transformer T1 is connected to one electrode, and the secondary non-like-named end of the step-up transformer T1 is connected to the other electrode and grounded.

[0084] The discharge switch control module controls the discharge switch circuit 300 in the following manner:

[0085] Assume that the defibrillation discharge time is t0, the discharge period is t1, and the discharge end time is t2, then:

[0086] At time t0, the first MOS tube K1 is turned on, and the charge in the energy storage capacitor 200 is applied to the primary side of the step-up transformer T1 through the discharge inductor L, and a defibrillation voltage and current are formed on the secondary side of the step-up transformer T1. Due to the existence of human body impedance between the pair of electrodes 400, according to Ohm's law, the voltage and current form a pulse electric field between the pair of electrodes 400;

[0087] During the period from time t0 to t1, a unipolar defibrillation pulse is outputted at the secondary side of the step-up transformer T1, and a preset energy is stored in the discharge inductor L;

[0088] At time t1, the first MOS tube K1 is disconnected, and a negative wave is generated on the secondary side of the boost transformer T1, resulting in the formation of a quasi-biphase wave.

[0089] Example 3, refer to Figure 4 This embodiment provides an ultrashort pulse defibrillator, including a DC power supply, an energy storage capacitor 200, a discharge switch circuit 300, a step-up transformer T1 and a pair of electrodes 400.

[0090] The DC power supply provides electric energy to the energy storage capacitor 200. Before defibrillation, the energy is stored in the energy storage capacitor 200 through the DC power supply. The voltage in the energy storage capacitor 200 is determined according to the voltage amplitude of the output pulse. Considering the withstand voltage of each switch tube in the discharge switch circuit, the voltage of the energy storage capacitor 200 should not be too high. Considering the influence of the transformation ratio of the step-up transformer T1, the voltage of the energy storage capacitor 200 should not be too high.

[0091] The energy storage capacitor 200 includes an electrolytic capacitor C1 and a film capacitor C2. The positive electrode of the electrolytic capacitor C1 is connected to the positive electrode of the DC power supply, and the negative electrode of the electrolytic capacitor C1 is connected to the negative electrode of the DC power supply. The film capacitor C2 is connected in parallel with the electrolytic capacitor C1. In actual implementation, the energy storage capacitor 200 is selected to be large enough so that only part of the energy is released during the discharge defibrillation process.

[0092] The discharge switch circuit 300 includes a first MOS tube K1, a second MOS tube K2, a discharge switch control module, a second protection diode Z2 and a third protection diode Z3. The drain of the first MOS tube K1 is connected to the non-same-name end of the step-up transformer T1, and the source of the first MOS tube K1 is connected to the negative electrode of the energy storage capacitor 200 and grounded. The drain of the second MOS tube K2 is connected to the same-name end of the primary side of the step-up transformer T1, and the source of the second MOS tube K2 is connected to the negative electrode of the energy storage capacitor 200 and grounded. The signal output end of the discharge switch control module is connected to the gate of the first MOS tube K1 and the gate of the second MOS tube K2 respectively, and the discharge switch control module is used to control the conduction or disconnection of the first MOS tube K1 and the conduction or disconnection of the second MOS tube K2. The second protection diode Z2 is a bidirectional voltage regulator, one end of the second protection diode Z2 is connected to the positive electrode of the energy storage capacitor 200, and the other end of the second protection diode Z2 is connected to the drain of the second MOS tube K2. The third protection diode Z3 is a bidirectional voltage regulator, one end of the third protection diode Z3 is connected to the positive electrode of the energy storage capacitor 200, and the other end of the third protection diode Z3 is connected to the drain of the first MOS tube K1.

[0093] The primary side of the boost transformer T1 has a center tap located in the middle, and the center tap of the boost transformer T1 is connected to the positive electrode of the energy storage capacitor 200. The secondary side of the boost transformer T1 has a same-name terminal connected to one electrode, and the secondary side of the boost transformer T1 has a non-same-name terminal connected to the other electrode and grounded.

[0094] The discharge switch control module controls the discharge switch circuit 300 in the following manner:

[0095] Assume that the defibrillation discharge time is t0, the discharge period is t1 and t2, and the discharge end time is t3, then:

[0096] At time t0, the second MOS tube K2 is turned on, and the first MOS tube K1 is turned off. The discharge current flows back from the energy storage capacitor 200 through the boost transformer T1 and the second MOS tube K2 to the energy storage capacitor 200. The primary voltage of the boost transformer T1 is equal to the voltage on the energy storage capacitor 200, and a high-voltage square wave is generated on the secondary side of the boost transformer T1.

[0097] At time t1, the second MOS tube K2 is disconnected, and the first MOS tube K1 is disconnected;

[0098] At time t2, the first MOS tube K1 is turned on, and the second MOS tube K2 is turned off. The discharge current flows back from the energy storage capacitor 200 through the step-up transformer T1 and the first MOS tube K1 to the energy storage capacitor 200. At this time, the magnetic field generated by the discharge current in the step-up transformer T1 changes in different directions, and a negative pulse is output on a pair of electrodes 400.

[0099] At time t3, the first MOS tube K1 and the second MOS tube K2 are both disconnected, and the defibrillation ends.

[0100] Embodiment 4, referring to Figure 5 This embodiment provides an ultrashort pulse defibrillator, including a DC power supply, an energy storage capacitor 200, a discharge switch circuit 300, a step-up transformer T1 and a pair of electrodes 400.

[0101] The DC power supply provides electric energy to the energy storage capacitor 200. Before defibrillation, the energy is stored in the energy storage capacitor 200 through the DC power supply. The voltage in the energy storage capacitor 200 is determined according to the voltage amplitude of the output pulse. Considering the withstand voltage of each switch tube in the discharge switch circuit, the voltage of the energy storage capacitor 200 should not be too high. Considering the influence of the transformation ratio of the step-up transformer T1, the voltage of the energy storage capacitor 200 should not be too high.

[0102] There are two energy storage capacitors 200, namely, a first energy storage capacitor C01 and a second energy storage capacitor C02, and a capacitor switch S1 is provided between the positive electrode of the first energy storage capacitor C01 and the positive electrode of the second energy storage capacitor C02. Before defibrillation, the first energy storage capacitor C01 and the second energy storage capacitor C02 are powered by a DC power supply. When the DC power supply supplies power to the first energy storage capacitor C01 and the second energy storage capacitor C02, different voltages can be charged to adjust the amplitude of the pulse.

[0103] The discharge switch circuit 300 includes a first MOS tube K1, a third MOS tube K3, a discharge switch control module, a fourth protection diode Z4 and a fifth protection diode Z5. The primary side of the boost transformer T1 includes two sets of primary coils, namely a first primary coil T11 and a second primary coil T12.

[0104] The drain of the first MOS tube K1 is connected to the non-same-name end of the first primary coil T11, and the source of the first MOS tube K1 is connected to the negative electrode of the first energy storage capacitor C01 and grounded. The drain of the third MOS tube K3 is connected to the same-name end of the second primary coil T12, and the source of the third MOS tube K3 is connected to the negative electrode of the second energy storage capacitor C02 and grounded. The signal output end of the discharge switch control module is connected to the gate of the first MOS tube K1 and the gate of the third MOS tube K3 respectively, and the discharge switch control module is used to control the conduction or disconnection of the first MOS tube K1 and the conduction or disconnection of the third MOS tube K3. The same-name end of the first primary coil T11 is connected to the positive electrode of the first energy storage capacitor C01, and the non-same-name end of the second primary coil T12 is connected to the positive electrode of the second energy storage capacitor C02. The fourth protection diode Z4 is a bidirectional voltage regulator, one end of the fourth protection diode Z4 is connected to the positive electrode of the first energy storage capacitor C01, and the other end of the fourth protection diode Z4 is connected to the drain of the first MOS tube K1. The fifth protection diode Z5 is a bidirectional voltage regulator, one end of the fifth protection diode Z5 is connected to the positive electrode of the second energy storage capacitor C02, and the other end of the fifth protection diode Z5 is connected to the drain of the third MOS tube K3.

[0105] The first energy storage capacitor C01, the boost transformer T1 and the first MOS tube K1 form a discharge loop, and the second energy storage capacitor C02, the boost transformer T1 and the third MOS tube K3 form another discharge loop.

[0106] The discharge switch control module controls the discharge switch circuit 300 in the following manner:

[0107] During defibrillation discharge, the first MOS tube K1 is turned on to release all the charges in the first energy storage capacitor C01, forming a positive defibrillation pulse on a pair of electrodes 400, and then the third MOS tube K3 is turned on to release all the charges in the second energy storage capacitor C02, forming a negative defibrillation pulse on the pair of electrodes 400. After the negative defibrillation pulse, the defibrillation process ends.

[0108] Example 5, refer to Figure 6 This embodiment provides an ultrashort pulse defibrillator, including a DC power supply, an energy storage capacitor 200, a discharge switch circuit 300, a step-up transformer T1 and a pair of electrodes 400.

[0109] The DC power supply provides electric energy to the energy storage capacitor 200. Before defibrillation, the energy is stored in the energy storage capacitor 200 through the DC power supply. The voltage in the energy storage capacitor 200 is determined according to the voltage amplitude of the output pulse. Considering the withstand voltage of each switch tube in the discharge switch circuit, the voltage of the energy storage capacitor 200 should not be too high. Considering the influence of the transformation ratio of the step-up transformer T1, the voltage of the energy storage capacitor 200 should not be too high.

[0110] The energy storage capacitor 200 includes an electrolytic capacitor C1 and a film capacitor C2. The positive electrode of the electrolytic capacitor C1 is connected to the positive electrode of the DC power supply, and the negative electrode of the electrolytic capacitor C1 is connected to the negative electrode of the DC power supply. The film capacitor C2 is connected in parallel with the electrolytic capacitor C1. In actual implementation, the energy storage capacitor 200 is selected to be large enough so that only part of the energy is released during the discharge defibrillation process.

[0111] The discharge switch circuit 300 includes a first MOS tube K1, a fourth MOS tube K4, a fifth MOS tube K5, a sixth MOS tube K6 and a discharge switch control module. The drain of the first MOS tube K1 is connected to the non-same-name end of the boost transformer T1, and the source of the first MOS tube K1 is connected to the negative electrode of the energy storage capacitor 200 and grounded. The drain of the fourth MOS tube K4 is connected to the positive electrode of the energy storage capacitor 200, and the source of the fourth MOS tube K4 is connected to the non-same-name end of the boost transformer T1. The drain of the fifth MOS tube K5 is connected to the positive electrode of the energy storage capacitor 200, and the source of the fifth MOS tube K5 is connected to the same-name end of the boost transformer T1. The drain of the sixth MOS tube K6 is connected to the same-name end of the boost transformer T1, and the source of the sixth MOS tube K6 is connected to the negative electrode of the energy storage capacitor 200 and grounded. The signal output end of the discharge switch control module is respectively connected to the gate of the first MOS tube K1, the gate of the fourth MOS tube K4, the gate of the fifth MOS tube K5, and the gate of the sixth MOS tube K6. The discharge switch control module is used to control the conduction or disconnection of the first MOS tube K1, the conduction or disconnection of the fourth MOS tube K4, the conduction or disconnection of the fifth MOS tube K5, and the conduction or disconnection of the sixth MOS tube K6.

[0112] The secondary like-named end of the step-up transformer T1 is connected to one electrode, and the secondary non-like-named end of the step-up transformer T1 is connected to the other electrode and grounded.

[0113] The discharge switch control module controls the discharge switch circuit 300 in the following manner:

[0114] Assume that the defibrillation discharge time is t0, the discharge period is t1 and t2, and the discharge end time is t3, then:

[0115] Before defibrillation, the first MOS tube K1 and the sixth MOS tube K6 are turned on, the fourth MOS tube K4 and the fifth MOS tube K5 are turned off, and both ends of the primary side of the boost transformer T1 are grounded;

[0116] At time t0, the fifth MOS tube K5 is turned on, the sixth MOS tube K6 is turned off, the same-name terminal of the primary side of the boost transformer T1 is connected to the positive electrode of the energy storage capacitor 200, the first MOS tube K1 is turned on, the fourth MOS tube K4 is turned off, the non-same-name terminal of the primary side of the boost transformer T1 is connected to the negative electrode of the energy storage capacitor 200, and a voltage is generated on the secondary side of the boost transformer T1 to form the first phase of the defibrillation waveform, only a small part of the voltage of the energy storage capacitor 200 is discharged, and the output waveform of the first phase is a square wave;

[0117] At time t1, the first MOS tube K1 and the sixth MOS tube K6 are turned on, the fourth MOS tube K4 and the fifth MOS tube are turned off, and both ends of the primary side of the boost transformer T1 are grounded. The primary side input voltage of the boost transformer T1 is zero, so the secondary side voltage of the boost transformer T1 is also zero.

[0118] At time t2, the fifth MOS tube K5 is turned off, the sixth MOS tube K6 is turned on, the same-name terminal of the primary side of the boost transformer T1 is connected to the negative electrode of the energy storage capacitor 200, the fourth MOS tube K4 is turned on, the first MOS tube K1 is turned off, the non-same-name terminal of the primary side of the boost transformer T1 is connected to the positive electrode of the energy storage capacitor 200, and a negative voltage is generated on the secondary side of the boost transformer T1 to form the second phase of the defibrillation waveform, and the output waveform of the second phase is a square wave;

[0119] At time t3, the first MOS tube K1, the fourth MOS tube K4, the fifth MOS tube K5 and the sixth MOS tube K6 are all disconnected, and the defibrillation ends.

[0120] The five embodiments of the present invention all have the characteristics of ultra-short pulse electric field. Due to the pulse action time, less energy is deposited on the ventricular cells, which reduces the damage of the defibrillation pulse to the myocardial cells.

[0121] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An ultrashort pulse defibrillator, comprising a DC power supply, a storage capacitor and a pair of electrodes connected in sequence, characterized in that: Also includes: a discharge switch circuit, disposed between the energy storage capacitor and a pair of the electrodes, for controlling the discharge time of the energy storage capacitor; a step-up transformer, disposed between the discharge switch circuit and a pair of the electrodes, the step-up transformer increasing the voltage on the energy storage capacitor to a preset amplitude; The discharge switch circuit comprises: a first MOS tube, the drain of which is connected to the non-same-name end of the boost transformer, and the source of which is connected to the negative electrode of the energy storage capacitor; a discharge switch control module, whose signal output end is connected to the gate of the first MOS tube and is used to control the on or off of the first MOS tube; There are two energy storage capacitors, namely a first energy storage capacitor and a second energy storage capacitor, and a capacitor switch is provided between the positive electrode of the first energy storage capacitor and the positive electrode of the second energy storage capacitor; The primary side of the step-up transformer includes two groups of primary coils, namely: a first primary coil, wherein the same-name end is connected to the positive electrode of the first energy storage capacitor, and the non-same-name end is connected to the drain of the first MOS transistor; a second primary coil, the non-identical end of which is connected to the positive electrode of the second energy storage capacitor; The source electrode of the first MOS tube is connected to the negative electrode of the first energy storage capacitor; The discharge switch circuit further includes: a third MOS tube, wherein the drain is connected to the same-name end of the second primary coil, the source is connected to the negative electrode of the second energy storage capacitor, and the gate is connected to the signal output end of the discharge switch control module; a fourth protection diode, which is a bidirectional voltage regulator, one end of which is connected to the positive electrode of the first energy storage capacitor, and the other end of which is connected to the drain of the first MOS tube; a fifth protection diode, which is a bidirectional voltage regulator, one end of which is connected to the positive electrode of the second energy storage capacitor, and the other end of which is connected to the drain of the third MOS tube; The first energy storage capacitor, the boost transformer and the first MOS transistor form a discharge loop, and the second energy storage capacitor, the boost transformer and the third MOS transistor form another discharge loop.

2. The ultrashort pulse defibrillator according to claim 1, characterized in that: The energy storage capacitor comprises: an electrolytic capacitor, a positive electrode of which is connected to the positive electrode of the DC power supply, and a negative electrode of which is connected to the negative electrode of the DC power supply; A film capacitor is connected in parallel with the electrolytic capacitor.

3. The ultrashort pulse defibrillator according to claim 1, characterized in that: The discharge switch control module controls the discharge switch circuit in the following manner: During defibrillation discharge, the first MOS tube is turned on to release all the charges in the first energy storage capacitor, forming a positive defibrillation pulse on the pair of electrodes, and then the third MOS tube is turned on to release all the charges in the second energy storage capacitor, forming a negative defibrillation pulse on the pair of electrodes. After the negative defibrillation pulse, the defibrillation process ends.

Images