RU2653794C1 - Device for induction of controlled hypothermia of the brain - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: group of inventions relates to medicine. Device for induction of controlled hypothermia of the subject's brain contains two cryoapplicators, a coolant cooling device, a hydraulic system, means for registering the temperature of at least one body portion of the subject and the control means. One cryoapplicator is made in the form of a cryo-applicator-helmet, the inner surface of which is in contact with the surface of the skin of the scalp of the subject's head. Another cryoapplicator is designed as a cryoapplicator-collar, the inner surface of which is in contact with the subject's neck in the area of the projection of the internal carotid arteries. Both cryo-applicators are designed to circulate in them a liquid coolant. Hydraulic system is arranged to circulate a liquid coolant in at least one of said cryoapplicators. Temperature recording means includes at least one antenna for non-invasive recording of the intrinsic EMV of the subject's deep tissues in the microwave range and the subsequent determination of the brain temperature of the subject. Control means is configured to control the cooling means of the coolant and the hydraulic system, as well as to determine the need for cooling cryoapplicators and the adequacy of hypothermia of the brain of the subject, depending on the data obtained with the help of these temperature recording facilities. Mmethod for inducing controlled hypothermia of the subject's brain includes: fixing the first cryoapplicator (cryo-applicator-collar) on the subject's neck, which requires lowering the temperature of the brain, and carrying out the cooling procedure through the first cryoapplicator for 15–120 minutes; measuring the rate of cooling of the subject's brain by means of an antenna for non-invasive recording of the EMR of the deep tissues of the subject in the microwave range; when determining the insufficient speed of cooling the brain of the subject, fixation of the second cryoapplicator (cryo-applicator-helmet) on the head of this subject and performing a cooling procedure using only the second cryoapplier or together the first and second cryoapplicators for an additional 60–120 minutes; measuring the rate of cooling of the subject's brain by means of an antenna for non-invasive recording of the EMR of the deep tissues of the subject in the microwave range and stopping cooling when the desired temperature of the brain is reached.

EFFECT: invention provides ability to select and monitor the brain cooling procedure of the subject by non-invasive temperature measurement, and also provides an increase in the accuracy of the regulation of the temperature of the brain during the hypothermia procedure, which reduces the side effects associated with excessive cold loads.

11 cl, 1 dwg

Description

Technical field

The invention relates to medicine, in particular to emergency medical care, traumatology, resuscitation and sports medicine, namely, it describes a device that allows efficient and controlled selective cooling of the brain of a subject.

State of the art

Therapeutic hypothermia is a well-known method of protecting the brain from the effects of hypoxia, ischemia, reperfusion and neurotrauma. The main objective of various methods of cooling patients with cerebral lesions is to lower the temperature of neurons.

Therapeutic hypothermia is reproduced by using a wide variety of devices that allow for brain cooling in accordance with the known mechanisms of natural cerebral thermoregulation - convection and conduction:

1) The convection mechanism consists in the flow of arterial blood to the brain through the internal carotid arteries, while the excess heat is carried away into the general venous blood flow. Arterial blood flowing to the brain through the internal carotid arteries is normal at rest colder than the blood in the aorta by about 0.2 ° C. Arterial blood is cooled due to the tight contact of the internal carotid arteries with the vessels of the jugular venous network, collecting blood from the mucous membranes of the upper respiratory tract, face and scalp, providing counter-current heat transfer. Venous blood flowing from the skin cools in the external environment, cooling arterial blood. When breathing, the mucous membranes of the nasopharynx are cooled, and the blood flowing from them also provides effective heat exchange with arterial blood. This mechanism is considered as the main one in maintaining the thermal balance of the brain. Consequently, a forced decrease in the temperature of the blood flowing to the brain will increase the removal of heat from the brain and lower its temperature. With general cooling of the body surface, venous blood and cooling of the skin in the area of projections of the carotid arteries, the temperature of the blood flowing to the brain decreases, which underlies the technical solutions of most devices for therapeutic hypothermia. In addition, cooling the scalp of the scalp helps lower the temperature of the flowing blood from the scalp to the jugular system and increases the efficiency of countercurrent heat transfer.

2) The conduction mechanism is to remove excess heat from the surface of the brain through the shells, flat bones of the skull and soft tissues of the head into the external environment due to heat conduction. The relatively low thermal conductivity of the flat bones of the skull and soft tissues of the head makes it difficult to remove heat, but with a decrease in the temperature of the scalp and an increase in the temperature difference between the skin and the cerebral cortex, the intensity of heat removal increases. Cooling the mucous membranes of the nasopharynx helps lower the temperature of the bones in the area of the base of the brain and also lowers the temperature of the base of the brain by conduction heat dissipation.

3) Another convection mechanism for cooling the surface of the brain is due to the anatomical features of the blood circulation of the scalp. Venous blood of the scalp through perforating holes directly enters the network of veins of the spongy substance of the flat bones of the skull into the emissary veins, which carry blood into the sinuses of the dura mater directly to the surface of the brain. Thus, the venous blood of the scalp cooled in the external environment is able to lower the blood temperature in the venous sinuses of the dura mater and provide a decrease in the surface temperature of the brain. Forced lowering of the temperature of the scalp increases the efficiency of this heat removal path.

In accordance with the indicated natural ways of transferring excess heat from the brain, all known devices for hypothermia by the principle of heat removal can be divided into the following groups:

1. Devices for cooling the surface of large areas of the body using cooled cryoapplicators (convection);

2. Device for cooling the blood of a patient using special cooled intravenous catheters (convection);

3. Devices for craniocerebral cooling using helmets-cryoapplicators (convection and conduction);

4. Devices for endonasal cooling of the mucous membranes of the nasopharynx with the help of easily evaporating sprays, cold air or cooled cylinders (convection and conduction);

5. Cooling devices for the projections of the carotid arteries (cooling collars) for cooling the blood flowing to the brain (convection).

The 1st and 2nd types of devices are aimed at lowering the temperature of the body and circulating blood, which, reaching the brain, provides a decrease in its temperature. With this methodological approach, body temperature is below brain temperature.

The 3rd, 4th and 5th types of devices provide a preferential decrease in brain temperature, but also contribute to lowering body temperature with a sufficiently long and vigorous heat removal. In these techniques, brain temperature is below body temperature.

Thus, in each of the listed devices, heat is removed from the brain through the natural pathways of heat transfer. It should be borne in mind that in various clinical situations, the contribution of each heat removal path to the process of lowering brain temperature during hypothermia induction can vary. Nevertheless, the choice of device and method for hypothermia has not yet been objectified. At the same time, the choice of an adequate cooling method and equipment as applied to a particular patient is crucial for obtaining the best clinical result. In particular, in patients with a high level of intracranial pressure and cerebral edema, the volumetric rate of cerebral blood flow, i.e. perfusion, decreases, which reduces the efficiency of cooling the brain with chilled blood due to the difficulty of its delivery to the lesion. Therefore, in these cases, the use of equipment and cooling methods that implement only the convection path of heat removal (1, 2, 5) will not be high compared with those patients in whom cerebral perfusion is preserved or only slightly reduced. The use of equipment based on craniocerebral and endonasal cooling under conditions of significantly reduced cerebral perfusion can be more effective, since they realize both convection and conduction paths of heat removal from the brain.

At the same time, the conduction path of heat removal from the brain during craniocerebral cooling is characterized by low efficiency due to the low thermal conductivity of the scalp, subcutaneous tissue and flat skull bones. This increases the developmental time of hypothermia in the brain compared with convection cooling. In addition, the surface area of heat removal from the scalp is not large. In turn, this reduces the efficiency of the total heat removal from the body and lengthens the time for lowering the temperature of the body and blood in comparison with general cooling, that is, the contribution of the convection path of cooling the brain is insignificant. It follows from this that it is more advisable to use combined (combined) cooling methods and appropriate equipment for the induction of hypothermia, taking into account the current state of cerebral thermoregulation systems and affecting convection and conduction mechanisms.

The most effective combined effect is the use of craniocerebral and collar cooling, since it includes convection and conduction heat removal paths. However, the authors did not consider endonasal cooling, since it is not applicable in severe patients requiring intubation and hypothermia for at least 24 hours.

It should be borne in mind that intense cold loads on the patient's body, in particular when using general cooling, carry a high risk of side effects and complications, such as depression of the cardiovascular system, disorders of water-electrolyte and acid-base balance, and infectious complications. At the same time, the risks of developing complications when applying general cooling are higher than with collar and craniocerebral cooling due to a higher level of cold load on the body. The danger of the development of complications of hypothermia is reflected in the Recommendations of the American Association of Cardiologists (2015) and the Recommendations of the European Resuscitation Council (2015), which states that after cardiopulmonary resuscitation during cooling, it is necessary to maintain body temperature at the level of normothermia or very mild hypothermia (not lower 35 ° C). However, a decrease in the intensity of heat removal from the brain reduces the neuroprotective effects of hypothermia.

In order to assess the quality and adequacy of the use of hypothermia, choose the optimal method of cooling, the level of cold load on the body and reduce the risks of complications, it is necessary to control the dynamics of changes in temperature of various parts of the body, as well as brain temperature. Most devices that implement the well-known methods of inducing hypothermia are equipped with means for recording the temperature of various parts of the body with the help of temperature sensors, which allow contact recording of the temperature of tissues. In particular, the temperature is recorded in the axillary region on the surface of the skin, in the esophagus, in the bladder, in the inner part of the ear canal (tympanic temperature). According to the measured temperature data, the achieved level of general cooling of the departments of the body is judged and, using controllers and automated control systems of the devices, they maintain the necessary level of heat removal, keeping the temperature of the departments of the body at a given level. It is significant that the temperature of the skin, internal organs or tympanic temperature does not reflect the true values of the temperature of the brain. In the acute period of brain damage, its temperature always exceeds basal, and brain hyperthermia can develop at normal body temperature (latent cerebral hyperthermia). In addition, in some cases with brain damage using sedatives, hypnotics and general anesthesia, its temperature decreases, cerebral hypothermia develops, and in these cases, additional cooling of the brain is not required.

Several non-invasive devices are known that selectively cool the brain and create conditions under which the temperature of the brain is below body temperature; such devices are described in US2013211484, US8529613, US6277143, US6183501, US8696726; Huan Wang et al., Translational Neuroscience, 2015, 6, p. 20-31; Poli S et al., Stroke, 2013 Mar; 44 (3): 708-13; Jackson K et al., Transl Neurosci., 2015 Jun 26; 6 (1): 131-138.

To date, there are no devices on the market for the induction of therapeutic hypothermia that would contain non-invasive means of determining brain temperature. Such devices would allow an individual choice of the cooling method and heat removal areas for each patient, control the cooling procedure and avoid the development of complications associated with excessive cold loads. This invention has a number of properties necessary to solve the problem.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an effective and safe device for inducing controlled hypothermia of a subject's brain. This problem is solved by creating a device that combines a combined brain cooling system with at least one non-invasive means of determining the temperature of deep tissues.

Some embodiments of the invention include a device for the induction of controlled hypothermia of the brain of a subject, containing at least two cryoapplicators, one of which is made in the form of a cryoapplicator-helmet, the inner surface of which contacts the skin surface of the scalp of the subject's head, and the other is made in the form of a cryoapplicator-collar, the inner surface of which is in contact with the neck of the subject, preferably in the projection region of the internal carotid arteries, both cryoapplicators flax with the possibility of circulation of a liquid coolant in them; coolant cooling means and a hydraulic system, wherein said hydraulic system is arranged to independently circulate a liquid coolant in at least one cryoapplicator; means for recording the temperature of at least one part of the body of the subject, which includes at least one antenna for detecting electromagnetic radiation (EMP) of the deep tissues of the specified subject in the microwave range for non-invasive determination of the brain temperature of the subject; and a control means that is configured to control the coolant coolant and the hydraulic system, as well as determine the need for combined or isolated karaniocerebral and / or collar cooling, as well as the sufficiency of the hypothermia of the brain of the subject, depending on the data obtained using these registration tools temperature.

In preferred embodiments of the invention, the control means is configured to provide independent control of the coolant circulation in the two cryoapplicators according to thermal monitoring, as well as to control the level of decrease in brain temperature based on non-invasive monitoring of brain temperature.

In some embodiments of the invention, an antenna for non-invasively detecting EMR of the subject’s deep tissues in the microwave range is designed to detect EMR in two frequency ranges of microwave radiation, and the control means is capable of averaging the brain temperature calculated on the basis of the measured EMR of the subject’s deep tissues antenna over two frequency ranges of microwave radiation.

In some embodiments of the invention, this device is characterized in that it further comprises at least one antenna capable of detecting electromagnetic radiation in the microwave range for non-invasively recording the temperature of the deep tissues of the subject, located so as to measure the internal temperature of the tissues in the area of the projection of the internal carotid artery. In other embodiments of the invention, the device comprises at least two antennas for non-invasive recording of brain temperature, which provide registration of EMR in two frequency ranges of microwave radiation.

In preferred embodiments of the invention, the control means is configured to provide a preferred choice of cooling areas — collar, craniocerebral or combined — based on monitoring data of brain temperature and, optionally, tissue temperature in the region of the carotid arteries.

In some embodiments of the invention, this device further comprises at least two antennas for detecting electromagnetic radiation in the microwave range for non-invasively determining the temperature of the deep tissues of the subject, located so as to measure the internal temperature of the tissues in the region of both projections of the two internal carotid arteries of the subject.

This problem is also solved by developing a method of inducing controlled hypothermia of the brain of the subject, carried out using the above-described device, which includes the following stages: a) fixing the first cryoapplicator (collar) on the neck of the subject, which requires lowering the temperature of the brain, and performing the cooling procedure through the first cryoapplicator within 15-120 minutes; b) measuring the cooling rate of the brain of the subject using an antenna for non-invasive registration of electromagnetic radiation of the deep tissues of the subject in the microwave range; c) when determining the insufficient cooling rate of the subject’s brain, fixing the second cryoapplicator (helmet) on the head of the subject and performing the cooling procedure using only the second cryoapplicator or together the first and second cryoapplicators for an additional 60-120 minutes; d) measuring the cooling rate of the brain of the subject using an antenna for non-invasive registration of electromagnetic radiation of the deep tissues of the subject in the microwave range and terminating the cooling procedure when the desired values of the brain temperature are reached.

When carrying out the invention, the following technical results are achieved:

- a new principle of the device for the selective cooling of the brain of the subject has been developed, which consists in the possibility of choosing and controlling the cooling procedure by non-invasively measuring the temperature of the brain of the subject, while the dynamics of the change in brain temperature will dictate the optimal cooling method selected from an isolated collar, isolated craniocerebral or combined craniocerebral and collar cooling;

- the proposed device provides improved accuracy in regulating the temperature of the brain during the hypothermia procedure, which allows to reduce side effects associated with excessive cold loads.

Brief Description of the Drawing

Fig. 1. Scheme of the procedure for inducing hypothermia of the brain in Option 1 (collar cooling), Option 2 (craniocerebral cooling), Option 3 (combined collar and craniocerebral cooling) with non-invasive brain thermometry using a dual-band antenna and tissue thermometry in the carotid artery, and in Option 4 (for example, combined collar and craniocerebral cooling) for non-invasive brain thermometry using a pair of two band antennas (sim metric left and right) and pairs of antennas for thermometry of tissues in the region of the carotid artery on the left and right.

Designations: GS - a hydraulic system, HA - a refrigeration unit, SU - a control tool, K - a controller, black circles - antennas for registering the electromagnetic radiation of the subject's deep tissues in the microwave range, white circles - cryo-applicator temperature sensors.

Definitions and Terms

For a better understanding of the present invention, the following are some of the terms used in the present description of the invention.

In the description of the present invention, the terms “includes” and “including” are interpreted as meaning “includes, inter alia,”. These terms are not intended to be construed as “consists of only”.

By “subject” is meant a human or other mammal. Under the EMP of the deep tissues of the subject should be understood the radiation of their own electromagnetic fields of body tissues. The induction of controlled hypothermia of the brain should be understood as inducing, or inducing, lowering the temperature of the brain to specified values in a controlled mode, that is, under the control of a control system (in automatic mode) or directly under the control of an operator (in manual mode).

By temperature recording, one should understand both direct temperature measurement and temperature determination by measuring the intrinsic electromagnetic radiation of deep tissues in the microwave range and subsequent temperature calculation. Determining the temperature during the cooling procedure by measuring the intrinsic electromagnetic radiation of deep tissues in the microwave range allows for non-invasive temperature monitoring, or thermal monitoring of the deep tissues of the subject.

By a cryoapplicator, one should understand a component of a device with a highly cooled surface in contact with tissues when exposed to local cold. In a preferred embodiment of the invention, the device for inducing controlled hypothermia uses two cryoapplicators, one of which is made in the form of a helmet, the inner surface of which is in contact with the head of the subject, and the other is made in the form of a collar, the inner surface of which is in contact with the neck of the subject. Preferably, the collar cryoapplicator contacts the projections of the human carotid arteries. The use of a cryoapplicator helmet provides craniocerebral cooling; cryoapplicator-collar - collar cooling; the use of both cryoapplicators provides combined, or combined, cooling.

 Unless defined separately, technical and scientific terms in this application have standard meanings generally accepted in the scientific and technical literature.

Detailed Disclosure of Invention

Therapeutic hypothermia of the brain improves the clinical performance of patients with traumatic brain injury, cerebral ischemia, ischemic encephalopathy and other diseases. At the same time, there are known negative cases of hypothermia associated with both ineffective or too slow lowering of the patient’s brain temperature, as well as with side effects caused by excessive cold loads. To ensure the efficiency and safety of the cooling procedure, it is necessary to carefully monitor the dynamics of the patient’s brain temperature and, if necessary, choose cooling methods that are more suitable for a particular patient.

Known devices for direct recording of brain temperature using implantable (invasive) temperature sensors, for example, Sofisa-Impressio. However, these devices can only be used in neurosurgical patients and hypothermia is not applicable in routine practice. Currently, microwave radiothermometry is the only non-invasive method for recording deep tissue temperature. Such devices allow you to register the power of your own electromagnetic radiation (EMR) of the subject's tissues in the range of super high frequencies (microwave, wavelength λ = 0.8-30 cm, frequency - 1-10 GHz) using contact antennas (or just antennas) placed on the surface of the skin and by calculation to determine the temperature values of deep tissues (patents RU2510236, RU2562025, RU2407429). An example of such a device is the commercially available radiometer RTM-01-RES, designed to record the temperature of deep breast tissue in order to detect temperature anomalies in diseases of the gland.

The power of EMR is proportional to the metabolic rate and therefore, by calculation it is possible to determine the internal temperature of tissues at different depths (Vesnin S.G., Sedankin M.K. Microwave radio thermometry of the brain. // Mashinostroitel, 2015, No. 11, p. 44-51). The depth of registration of tissue temperature using registration EMR also depends on the frequency (wavelength) of the detected radiation. So, it was shown that when registering EMR with a frequency of 3-4 GHz, it is possible to estimate the temperature of the brain at a depth of 4-5 cm from the skin surface, which corresponds to the temperature of the surface of the cortex of the cerebral hemispheres in the temporal region. Registration of EMP with a frequency of 1.5-2 GHz allows you to estimate the temperature of brain tissue at a depth of 5-7 cm, that is, in the volume of all gray matter on the surface of the brain. The temperature recorded in this way is averaged over a sufficiently large volume of tissue. The use of dual-band antennas makes it possible to increase the accuracy of measurements and, potentially, to record thermal asymmetry in various parts of the brain.

In order to create an effective device for the induction of therapeutic controlled hypothermia of the brain, the authors proposed to connect one or more cryoapplicators with a device for recording the subject's own electromagnetic radiation of deep tissues in the microwave range to monitor the subject's brain temperature during the cooling procedure. To increase the cooling efficiency in patients with impaired intracerebral circulation, it was proposed to use at least two cryoapplicators - a collar applicator for cooling the skin in the neck (preferably, projections of the carotid arteries) and a helmet-cryoapplicator for cooling the scalp. Cryoapplicators, for the cooling of which refrigerant circulation is used, are well known to specialists (for example, see patent RU74563 - Applicator for hypothermia). The use of two cryoapplicators gives the necessary flexibility in the choice of cooling methods; for example, only craniocerebral, only collar or a combination of collar and craniocerebral cooling can be used. Monitoring the temperature of the brain during cooling allows you to evaluate the effectiveness of a particular method and, if necessary, replace it with a more effective or safe method. Means of recording temperature also allow you to track in time the adequacy of hypothermia in the brain and initiate the termination of the cooling procedure, thereby reducing side effects associated with excessive cold loads. Thus, by tracking the dynamics of the temperature of the brain of the subject, such a design allows you to choose the optimal method of cooling, and to control the cooling procedure.

The described device also contains a means of cooling cryoapplicators, a hydraulic system for circulating the coolant in the cryoapplicators for cooling them, a means for controlling the temperature of the coolant, a means for controlling the temperature in the cryoapplicators in the area of contact with the skin, a means for registering basal temperature (body temperature), at least one means for non-invasive temperature recording deep tissue for measuring EMR, as well as a controller and a means of controlling the operation of the device, ensuring the maintenance of mperatury krioapplikatorov, body temperature and brain at a given level. EMR detection can be carried out using the standard microwave recorder RTM-01-RES, or any other device that allows you to register EMR of tissues in the range from 2 to 6 GHz.

In some embodiments of the invention, it is possible to use devices containing cooling means of a compressor-type liquid coolant or on thermoelectric elements, a hydraulic system with a coolant tank, fluid supply pipes, pumps and valves providing closed circulation of the coolant from the tank to the cooling medium, then to cryoapplicators with subsequent return of the liquid coolant to the tank. The circulation of liquid coolant can be carried out independently in each applicator.

In this case, cryoapplicators (collar and helmet) are sealed devices, the shape and dimensions of which correspond to the surface configuration of the cooled areas, and the inside contains the channels of circulation of the liquid coolant. An aqueous solution of a liquid, for example, propylene glycol, which does not freeze at low temperatures (up to minus 10 ° С), is used as a coolant, which can significantly increase the intensity of heat removal from cooled surfaces and accelerate the decrease in tissue temperature. The automated control tool monitors the recorded temperatures and maintains them at a preset level (settings) by applying a control signal (on / off) to the liquid coolant cooling means, changing the intensity of heat removal from the cooled areas of the subject's body and / or the control signal to the pumps and / or valves that interrupt the circulation of the coolant in the cryoapplicators or a particular cryoapplicator. Moreover, the choice of preferred areas of cooling, for example, the use of isolated or combined craniocerebral and collar cooling can be carried out on the basis of non-invasive recording of brain temperature. In this embodiment, the use of known devices is carried out taking into account the independent use of non-invasive registration of deep human tissues, based on the location of EMR in the microwave range and on the algorithm of the method of using the inventive device.

 The described device may also contain at least two means of non-invasive recording of brain temperature, which can be installed, for example, symmetrically at the border of the scalp of the scalp, preferably in the temporal region, left and right. The controller and control will monitor and compare brain temperature recorded on the left and right. In this case, it is possible to register the temperature asymmetry (thermal asymmetry) of different parts of the brain (Δt ° С) of the subject. Information on the occurrence and dynamics of the development of thermal asymmetry may be useful in assessing the state of the brain in subjects with traumatic brain damage of various origins, cerebrovascular accidents, neuro-oncology, etc.

The following examples of the operation of the device are provided in order to disclose the characteristics of the present invention and should not be construed as in any way limiting the scope of the invention.

Option 1 (see Fig. 1 for this and other options). At the border of the scalp of the scalp, on the skin surface, preferably in the temporal region to the right or left in the projection of the subject’s hemisphere of interest, the first means for non-invasive recording of brain temperature is installed - at least one applicator antenna. A cryoapplicator collar is fixed on the patient’s neck, the internal (cooled) parts of which are in contact with the skin in the projection area of the carotid arteries on the left and right. In the projection area of the carotid artery above the collar, a second means for non-invasively recording the temperature in the region of the carotid artery can be installed - at least one antenna applicator left or right. At least one temperature sensor is fixed on the patient’s body to record basal skin temperature. After switching on, the cooling means lowers the temperature of the coolant to a predetermined level, after which the control automatically turns on the pumps of the hydraulic system and circulates the coolant and lowers the temperature of the cryoapplicator collar. The controller monitors the temperature of the coolant, the temperature of the cryoapplicator collar in the area of contact with the skin, body temperature, brain temperature and carotid artery temperature. The first means of non-invasive recording of brain temperature preferably provides registration of EMR in at least two microwave ranges, for example, with a frequency of 1.5-2 GHz and 3-4 GHz. The second means of non-invasive temperature registration provides the registration of radiation in at least one frequency range of the electromagnetic radiation, for example, 3-4 GHz. The control tool calculates the average temperature of the brain using the first means of recording the temperature of the brain according to the power of the EMP, measured in two microwave ranges after the averaging procedure. The signal from the second means of recording temperature allows you to register the temperature in the region of the carotid artery. A decrease in brain temperature recorded after the start of cooling of the projections of the carotid arteries through an interval of time, for example, after 15-30 minutes, indicates sufficient cerebral perfusion, the effectiveness of collar cooling and the absence of the need to supplement the hypothermia procedure with craniocerebral cooling. The control means generates a signal to the user about the adequacy of cooling. This reduces the total cold load on the body and helps to prevent the development of complications of general hypothermia. The patient is not wearing a helmet, which helps to preserve the natural ways of maintaining the thermal balance of the brain. Lowering the temperature of the brain and the temperature in the region of the carotid arteries indicates the effectiveness of the cooling procedure.

Option 2. It is used in cases where the temperature of the brain does not decrease or does not drop enough after the cooling of the projections of the carotid arteries begins, as described in Option 1. The control tool generates a signal about the inefficiency (low efficiency) of the collar cooling and the need to supplement the procedure with craniocerebral cooling. A cryo-applicator helmet is put on the patient’s head, positioning it so as not to cause a shift in the first means of non-invasive recording of brain temperature. In special through holes of the helmet, at least one temperature sensor is fixed to measure the temperature in the area of contact of the cryo-applicator with the skin, the helmet is connected to the hydraulic system, which lowers its temperature to a predetermined level. The controller monitors the temperature recorded by the first and second means of non-invasive temperature recording, and the control tool evaluates the effectiveness of craniocerebral cooling by the degree of decrease in brain temperature and, optionally, the temperature in the carotid artery. A decrease in the temperature of the brain and carotid artery indicates the sufficiency of craniocerebral cooling and the absence of collar cooling, since the blood flowing from the scalp cools the blood in the carotid arteries, supplementing the convection path of heat dissipation and thereby replacing the collar type of cooling. The control means generates a signal to the user, after which the cooling of the collar area is stopped, which reduces the total cold load. The collar is removed.

Option 3. In cases where the temperature of the brain does not decrease (does not decrease sufficiently) with isolated craniocerebral cooling, as described in Option 2, which indicates gross violations of cerebral perfusion and the development of cerebral edema, the control tool generates a signal to the user about the need to supplement the collar procedure cooling. Such combined (combined) cooling, even with reduced perfusion of the brain, increases the intensity of heat removal from the brain, helping to reduce cerebral edema and restore cerebral hemocirculation. Upon restoration of cerebral perfusion, established on the basis of lowering the temperature of the brain to the desired level, collar cooling is turned off, and the control means evaluates the adequacy of isolated craniocerebral cooling based on changes in the temperature of the brain and carotid arteries and sends a signal to the user.

In all cases, the control means when the temperature of the coolant deviates from the set one, gives a control signal to the cooling means, changing the level of refrigerating capacity of the refrigerating unit. As a refrigeration unit can be a compressor refrigeration machine or thermoelectric elements. When the temperature deviates in the area of contact of the cryoapplicators with the skin and the body temperature from a predetermined one, the control means provides a control signal to the actuating means of the hydraulic system (pumps, valves), changing the volume velocity of the coolant in the channels of the cryoapplicators to maintain the temperature at a predetermined level. The hydraulic system provides cooling of both cryoapplicators independently of each other. The controller monitors all recorded temperatures throughout the cooling procedure. The control tool generates a signal to the user (sound / light) in cases where there is no decrease in temperature in the carotid artery, with an increase in brain temperature, informing about the need for combined (combined) or isolated cooling, as well as about cases of uncontrolled deviation of recorded temperatures from predetermined ones.

Option 4. In another particular case, the device uses at least two means of non-invasive recording of brain temperature in two ranges of electromagnetic radiation, which are installed symmetrically on the border of the scalp of the scalp, preferably in the temporal region, left and right. At least two non-invasive means of recording the temperature of the carotid arteries in at least one EMR range are also used, which are installed on the left and right in the projection region of the carotid arteries above the cryoapplicator collar. The controller and control tool provide monitoring and comparison of brain temperature recorded on the left and right, as well as the carotid arteries on the left and right. In case of asymmetry of the temperature of the brain above a predetermined (Дt ° С), which indicates the unevenness of the cooling of the brain, the control tool generates a signal to the user about the need to check the position of the helmet on the head (loose fit, etc.). The appearance of temperature asymmetry in the carotid arteries indicates uneven cooling in the collar cryoapplicator and the control means gives the corresponding signal to the user.

This option implements a technical solution that is aimed at improving the accuracy of recording the temperature of the brain and carotid arteries and ensuring the effectiveness of the hypothermia procedure.

Although the invention has been described with reference to the disclosed embodiments, it will be apparent to those skilled in the art that the specific experiments described in detail are for illustrative purposes only and should not be construed as limiting the scope of the invention in any way. It should be understood that various modifications are possible without departing from the gist of the present invention.

Claims (19)

1. A device for the induction of controlled hypothermia of the brain of a subject, containing at least: a) two cryo-applicators, one of which is made in the form of a cryo-applicator-helmet, the inner surface of which is in contact with the skin surface of the scalp of the subject’s head, and the other is made in the form of a cryo-applicator-collar, whose inner surface is in contact with the subject’s neck in the projection area of the internal carotid arteries, both cryoapplicators are configured to circulate a liquid coolant in them; b) a coolant cooling means and a hydraulic system, wherein said hydraulic system is arranged to circulate a liquid coolant in at least one cryoapplicator; c) means for recording the temperature of at least one region of the subject’s body, which include at least one antenna for non-invasively recording the intrinsic electromagnetic radiation of the deep tissues of the subject in the microwave range and then determining the temperature of the brain of the subject; g) a control tool that is configured to control the coolant coolant and the hydraulic system, as well as determine the need for cooling the cryoapplicators and the sufficiency of the hypothermia of the brain of the subject, depending on the data obtained using the indicated temperature recording means. 2. The device according to claim 1, characterized in that the control means is configured to provide independent control of the coolant circulation in two cryoapplicators according to non-invasive thermal monitoring data. 3. The device according to claim 2, characterized in that the control means is configured to provide control of the level of lowering the temperature of the brain based on non-invasive monitoring of brain temperature. 4. The device according to p. 3, characterized in that the antenna for non-invasive recording of brain temperature is designed to detect EMR in two frequency ranges of microwave radiation. 5. The device according to claim 4, characterized in that the control means is configured to average the temperature of the brain of the subject over two values calculated on the basis of the measured electromagnetic radiation of the deep tissues of the subject by the specified antenna in two frequency ranges of microwave radiation. 6. The device according to p. 3, characterized in that the control means is configured to provide a preferred choice of cooling areas - collar, craniocerebral or combined - based on data from monitoring brain temperature. 7. The device according to p. 6, characterized in that it further comprises at least one antenna for non-invasively recording the electromagnetic radiation of the deep tissues of the subject in the microwave range, located so as to measure the temperature of the tissues in the region of the carotid artery of the subject. 8. The device according to p. 7, characterized in that the control means is configured to provide a preferred choice of cooling areas - collar, craniocerebral or combined - based on monitoring data of the temperature of the brain and tissues in the region of the carotid arteries. 9. The device according to p. 8, characterized in that it contains at least two antennas for non-invasive registration of electromagnetic radiation of the deep tissues of the subject, each of which is designed to detect electromagnetic radiation of the deep tissues of the subject in two frequency ranges of microwave radiation. 10. The device according to p. 6, characterized in that it further comprises at least two more antennas for non-invasive recording of temperature in the microwave range of the native electromagnetic radiation of the deep tissues of the subject, located so as to measure the internal temperature of the tissues in the region of both carotid arteries of the subject. 11. The method of inducing controlled hypothermia of the brain of a subject, carried out using the device according to any one of paragraphs. 1-10, including: a) fixing the first cryoapplicator (cryoapplicator-collar) on the neck of a subject who needs a decrease in brain temperature, and performing a cooling procedure through the first cryoapplicator for 15-120 minutes; b) measuring the cooling rate of the brain of the subject using an antenna for non-invasive registration of electromagnetic radiation of the deep tissues of the subject in the microwave range; c) when determining the insufficient cooling rate of the subject’s brain, fixing the second cryoapplicator (cryoapplicator-helmet) on the head of the subject and performing the cooling procedure using only the second cryoapplicator or together the first and second cryoapplicators for an additional 60-120 minutes; g) measuring the cooling rate of the brain of the subject using an antenna for non-invasive registration of electromagnetic radiation of the deep tissues of the subject in the microwave range and stopping cooling when the desired values of the brain temperature are reached.

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