Continuous body temperature automatic adjusting method and system

Abstract

The invention provides a continuous body temperature automatic adjusting method and system. The method comprises the steps that the artery side temperature and the vein side temperature in an extracorporeal circulation blood pipeline are collected, pipeline heat loss compensation is conducted on the artery side temperature and the vein side temperature, and the fistula arterial blood temperature and the fistula vein blood temperature are obtained; measuring a vascular access recirculation percentage, and calculating an initial central body temperature based on the fistula arterial blood temperature, the fistula venous blood temperature, and the recirculation percentage; calculating the target venous blood temperature at the fistula by taking the initial central body temperature as the target central body temperature; performing pipeline heat loss compensation on the target venous blood temperature at the fistula to obtain the target temperature of dialysate; and the temperature of the dialysate is controlled, so that the dialysate is stabilized at the target temperature of the dialysate. According to the method, the accuracy of calculation of the central body temperature of the patient is improved, the central body temperature of the patient can be automatically controlled, manual control is not needed, and the method can adapt to individual differences of initial body temperatures of different patient crowds.

Description

Technical Field

[0001] The present invention relates to the technical field of hemodialysis, and in particular to a method and system for continuous automatic temperature regulation. Background Art

[0002] Body temperature is an important physiological indicator during hemodialysis. If the patient's body temperature is increased or decreased too quickly during treatment, it will cause discomfort and harm to the patient. During hemodialysis, patients generally have an increase in body temperature due to the generation of endogenous heat. Obviously, this is not conducive to the treatment of patients. To solve this problem, the dialyzer is usually used as a heat exchange site between blood and dialysate during treatment, and the patient's body temperature is indirectly adjusted by adjusting the dialysate temperature. Mainly: before treatment, medical staff can use a thermometer to measure the patient's body temperature and set an appropriate dialysate temperature during treatment. During the treatment, a constant dialysate temperature (such as 37°C) is used, or a pre-set dialysate temperature change curve is used, that is, the dialysate temperature is automatically adjusted over time according to the curve change law.

[0003] The existing adjustment methods generally have the following problems:

[0004] 1. Manual temperature measurement adds unnecessary steps and has high labor costs.

[0005] 2. The patient's body temperature is often not a fixed value, and the preset dialysate temperature cannot provide selective treatment based on the individual differences in the patient's body temperature. Summary of the invention

[0006] In order to overcome the defects in the prior art, the object of the present invention is to provide a method and system for continuous automatic temperature regulation.

[0007] In order to achieve the above-mentioned object of the present invention, the present invention provides a method for continuous automatic temperature regulation, comprising the following steps:

[0008] During the dialysis stage, the arterial and venous temperatures in the extracorporeal blood circulation circuit are collected in real time, and the arterial and venous temperatures are compensated for the heat loss of the circuit to obtain the arterial and venous blood temperatures at the fistula, and an arteriovenous blood temperature curve is generated based on the arterial and venous blood temperatures at the fistula;

[0009] Regularly measuring the recirculation percentage of the vascular access, and calculating the initial central body temperature based on the arterial blood temperature at the fistula, the venous blood temperature at the fistula, and the recirculation percentage;

[0010] The initial central body temperature was used as the target central body temperature to calculate the target venous blood temperature at the fistula;

[0011] The target venous blood temperature at the fistula is compensated for the heat loss in the pipeline to obtain the target temperature of the dialysate;

[0012] The dialysate temperature is controlled to stabilize it at the dialysate target temperature.

[0013] This method takes into account the impact of vascular access recirculation on body temperature measurement, improves the accuracy of calculating the patient's central body temperature, can automatically control the patient's central body temperature without manual control, and can adapt to the individual differences in initial body temperature of different patient populations.

[0014] In an optional solution of the continuous body temperature automatic regulation method, the initial central body temperature Among them, T art0 T is the initial arterial blood temperature at the fistula site; ven0 is the initial venous blood temperature at the fistula, R 0 is the recirculation percentage of the initial measurement;

[0015] The target venous blood temperature at the fistula Among them, T art is the real-time arterial blood temperature at the fistula, R is the recirculation percentage, [t 1 , t 2 ] refers to the pulse integration interval on the arteriovenous blood temperature curve when measuring the recirculation percentage, T art (t) refers to the arterial blood temperature at the fistula at time t on the arteriovenous blood temperature curve, T ven (t) refers to the venous blood temperature at the fistula at time t on the arteriovenous blood temperature curve.

[0016] In an alternative embodiment of the continuous thermoregulation method, the measuring steps of the recirculation percentage R are:

[0017] An arteriovenous blood temperature curve is generated according to the arterial blood temperature and venous blood temperature at the fistula;

[0018] A temperature change pulse is injected into the artery and vein through dialysate, and the recirculation percentage is calculated based on the stress pulse portion of the temperature change pulse generated by the arteriovenous blood temperature curve.

[0019] In an optional solution of the continuous body temperature automatic regulation method, a target central body temperature change trend is set before the start of dialysis or during dialysis, and a target central body temperature change curve is generated according to the initial central body temperature and the target central body temperature change trend;

[0020] During dialysis, the temperature of the arterial side and the venous side of the extracorporeal blood circulation circuit are collected in real time;

[0021] During dialysis, the target venous blood temperature at the fistula at time t is calculated according to the target central body temperature curve;

[0022] The target venous blood temperature at the fistula at time t is compensated for the heat loss in the pipeline to obtain the target dialysate temperature at time t.

[0023] This optional solution continuously measures the patient's body temperature on the original basis, so that the patient's blood temperature during hemodialysis is consistent with the temperature on the target central body temperature curve. It is particularly suitable for people whose initial blood temperature is too low or too high.

[0024] In an alternative embodiment of the continuous temperature autoregulation method, the target venous blood temperature at the fistula at time t is Among them, T bt is the target central body temperature at time t on the target central body temperature curve, T artt is the arterial blood temperature at the fistula at time t.

[0025] In an optional scheme of the continuous body temperature automatic regulation method, an upper limit and a lower limit of the dialysate temperature are set. When the dialysate target temperature is higher than the upper limit of the dialysate temperature, the upper limit of the dialysate temperature is used as the dialysate target temperature; when the dialysate target temperature is lower than the lower limit of the dialysate temperature, the lower limit of the dialysate temperature is used as the dialysate target temperature.

[0026] This optional solution ensures that the patient's body temperature is always automatically adjusted within a safe range during the hemodialysis process.

[0027] The present invention also proposes a continuous body temperature automatic regulation system including a dialysate temperature controller, an arterial temperature sensor for collecting the arterial side temperature and a venous temperature sensor for collecting the venous side temperature in an extracorporeal blood circulation pipeline;

[0028] The signal output ends of the arterial temperature sensor and the venous temperature sensor are respectively connected to the corresponding signal input ends of the dialysate temperature controller; the dialysate temperature controller calculates the dialysate target temperature based on the arterial side temperature and the venous side temperature according to the above-mentioned continuous body temperature automatic adjustment method, and adjusts the dialysate temperature according to the dialysate target temperature.

[0029] In an optional solution of the continuous body temperature automatic regulation system, a heating module is also included, and the heating module is connected to the dialysate temperature controller. The dialysate temperature controller controls the heating module to heat the dialysate so that the dialysate temperature is consistent with the dialysate target temperature.

[0030] The beneficial effects of the present invention are: the present invention continuously measures the patient's body temperature, takes into account the impact of vascular access recirculation on body temperature measurement, improves the accuracy of calculating the patient's central body temperature, can automatically control the patient's central body temperature without manual measurement and control, and can adapt to the individual differences in initial body temperature of different patient populations. During hemodialysis, the patient's body temperature is measured in real time and automatically adjusted within a safe range, so that the patient's body temperature reaches or is maintained near the expected target after the treatment.

[0031] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0033] Figure 1 This is a schematic diagram of the installation of arterial temperature sensor and venous temperature sensor. DETAILED DESCRIPTION

[0034] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0035] In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal connection between two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0036] Embodiment 1

[0037] The present invention provides a continuous body temperature automatic regulation method, which is particularly applicable to the field of hemodialysis. Specifically, it comprises the following steps:

[0038] like Figure 1 As shown, an arterial temperature sensor for collecting the temperature of the arterial side is arranged on the arterial side of the extracorporeal blood circulation pipeline, and a venous temperature sensor for collecting the temperature of the venous side is arranged on the venous side of the extracorporeal blood circulation pipeline.

[0039] During the dialysis phase, the arterial and venous temperatures of the extracorporeal blood circuit are collected in real time, and the arterial and venous temperatures are compensated for the heat loss of the circuit to obtain the arterial and venous blood temperatures at the fistula. The details are as follows:

[0040]

[0041] Among them, T art is the real-time arterial blood temperature at the fistula, T ven is the real-time venous blood temperature at the fistula, T art ' is the arterial temperature, T ven ′ is the temperature on the venous side, C art C is the temperature loss compensation value of the arterial blood line from the fistula to the arterial temperature sensor, ven C is the temperature loss compensation value of the venous blood line from the venous temperature sensor to the fistula, art and C ven The value of can be determined based on factors such as the tube material, tube length, and blood flow in the tube.

[0042] The percentage of vascular access recirculation was measured periodically.

[0043] The vascular access recirculation percentage can be measured using existing known methods. In this embodiment, the following method is used:

[0044] An arteriovenous blood temperature curve is generated based on the arterial blood temperature and venous blood temperature at the fistula.

[0045] Then, based on the known principle of thermal dilution, recirculation measurement is performed non-invasively: a short temperature change pulse is actively generated by the dialysate side, such as a temperature change pulse of about 2.5°C, that is, when the current temperature rises or falls by 2.5°C, the arteriovenous blood temperature curve will generate a stress pulse. The recirculation percentage is calculated based on the stress pulse generated by the arteriovenous blood temperature curve to the temperature pulse. The calculation formula is as follows:

[0046]

[0047] Among them, [t 1 , t 2 ] refers to the pulse integration interval on the arteriovenous blood temperature curve when measuring the recirculation percentage. It is set manually. art (t) refers to the arterial blood temperature at the fistula at time t on the arteriovenous blood temperature curve, T ven (t) refers to the venous blood temperature at the fistula at time t on the arteriovenous blood temperature curve. The initial central body temperature is calculated based on the arterial blood temperature at the fistula, the venous blood temperature at the fistula, and the recirculation percentage. The calculation formula is as follows:

[0048]

[0049] Among them, T b is the initial central body temperature, T art0 T is the initial arterial blood temperature at the fistula site; ven0 is the initial venous blood temperature at the fistula, R 0 is the recirculation percentage of the initial measurement.

[0050] The initial central body temperature is used as the target central body temperature to calculate the target venous blood temperature at the fistula. The formula for calculating the target venous blood temperature at the fistula is as follows:

[0051]

[0052] R is the recirculation percentage, which is measured at the set measurement frequency. Each time it is used to calculate the target venous blood temperature at the fistula, the latest recirculation percentage is used in the calculation. If the recirculation percentage is only measured once during the entire dialysis process, that is, the recirculation percentage R measured initially 0 , then R 0 Participate in calculations.

[0053] The target venous blood temperature at the fistula is compensated for the heat loss in the pipeline to obtain the target dialysate temperature, that is, the dialysate target temperature T dial =T ven ″+C ven .

[0054] To ensure safety, set the upper and lower limits of the dialysate temperature. When the dialysate target temperature is higher than the upper limit of the dialysate temperature, the upper limit of the dialysate temperature is used as the dialysate target temperature; when the dialysate target temperature is lower than the lower limit of the dialysate temperature, the lower limit of the dialysate temperature is used as the dialysate target temperature. For example, 35°C is used as the lower limit of the dialysate temperature and 38°C is used as the upper limit of the dialysate temperature, resulting in:

[0055]

[0056] Then the dialysate temperature is controlled to stabilize it at the dialysate target temperature, ensuring that the patient's blood temperature is continuously maintained at the initial central body temperature T during the dialysis process. b .

[0057] Embodiment 2

[0058] This embodiment is the same as the first embodiment, in which an arterial temperature sensor for collecting the temperature of the arterial side is arranged on the arterial side of the extracorporeal blood circulation pipeline, and a venous temperature sensor for collecting the temperature of the venous side is arranged on the venous side of the extracorporeal blood circulation pipeline.

[0059] The target central body temperature change trend is set before the start of dialysis or during dialysis, and the target central body temperature change curve is generated according to the initial central body temperature and the target central body temperature change trend.

[0060] During the dialysis process, the arterial and venous temperatures of the extracorporeal blood circuit are collected in real time, and the arterial and venous temperatures are compensated for the heat loss of the circuit to obtain the arterial and venous blood temperatures at the fistula.

[0061] During dialysis, the target venous blood temperature at the fistula at time t is calculated according to the target central body temperature curve;

[0062] Target venous blood temperature at fistula at time t Among them, T bt is the target central body temperature at time t on the target central body temperature curve, T artt is the arterial blood temperature at the fistula at time t, T artt =T artt ′+C art , T artt ' is the arterial temperature at time t.

[0063] The target venous blood temperature at the fistula at time t is compensated for the heat loss of the pipeline to obtain the target dialysate temperature at time t, that is, the target dialysate temperature T at time t. dialt =T ven ″ t +C ven .

[0064] In order to ensure safety, the upper and lower limits of the dialysate temperature can also be set as in Example 1. When the dialysate target temperature is higher than the upper limit of the dialysate temperature, the upper limit of the dialysate temperature is used as the dialysate target temperature; when the dialysate target temperature is lower than the lower limit of the dialysate temperature, the lower limit of the dialysate temperature is used as the dialysate target temperature. For example, 35°C is used as the lower limit of the dialysate temperature and 38°C is used as the upper limit of the dialysate temperature, thus obtaining:

[0065]

[0066] The dialysate temperature is then controlled so that it changes along the target central body temperature curve, ensuring that the patient's blood temperature during the dialysis process is consistent with the temperature on the target central body temperature curve.

[0067] Embodiment 3

[0068] This embodiment also provides a continuous body temperature automatic regulation system, including a dialysate temperature controller, an arterial temperature sensor for collecting the arterial temperature of an extracorporeal blood circulation line and a venous temperature sensor for collecting the venous temperature, and a heating module. The signal output ends of the arterial temperature sensor and the venous temperature sensor are respectively connected to the corresponding signal input ends of the dialysate temperature controller, and the heating module is controlled and connected to the dialysate temperature controller.

[0069] The dialysate temperature controller calculates the dialysate target temperature based on the arterial side temperature and the venous side temperature according to the continuous body temperature automatic adjustment method described in Example 1 or Example 2, and controls the heating module to heat the dialysate with the dialysate target temperature as the target, so that the dialysate temperature is consistent with the dialysate target temperature, thereby adjusting the dialysate temperature.

[0070] A dialysate temperature sensor may be provided to collect the temperature of the dialysate to confirm whether the dialysate temperature is consistent with the dialysate target temperature. The signal output end of the dialysate temperature sensor is connected to the corresponding signal input end of the dialysate temperature controller.

[0071] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0072] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for continuous automatic temperature regulation, characterized in that: The following steps are involved: During the dialysis stage, the arterial and venous temperatures in the extracorporeal blood circulation circuit are collected in real time, and the arterial and venous temperatures are compensated for the heat loss of the circuit to obtain the arterial and venous blood temperatures at the fistula, and an arteriovenous blood temperature curve is generated based on the arterial and venous blood temperatures at the fistula; Regularly measuring the recirculation percentage of the vascular access, and calculating the initial central body temperature based on the arterial blood temperature at the fistula, the venous blood temperature at the fistula, and the recirculation percentage; The initial central body temperature was used as the target central body temperature to calculate the target venous blood temperature at the fistula; The target venous blood temperature at the fistula is compensated for the heat loss in the pipeline to obtain the target temperature of the dialysate; The dialysate temperature is controlled to stabilize it at the dialysate target temperature.

2. The continuous body temperature automatic regulation method according to claim 1, characterized in that: The initial central temperature Among them, T art0 T is the initial arterial blood temperature at the fistula site; ven0 is the initial venous blood temperature at the fistula, R0 is the recirculation percentage measured initially; The target venous blood temperature at the fistula Among them, T art is the real-time arterial blood temperature at the fistula, R is the recirculation percentage, [t1, t2] refers to the pulse integration interval on the arteriovenous blood temperature curve when measuring the recirculation percentage, T art (t) refers to the arterial blood temperature at the fistula at time t on the arteriovenous blood temperature curve, T ven (t) refers to the venous blood temperature at the fistula at time t on the arteriovenous blood temperature curve.

3. The continuous body temperature automatic regulation method according to claim 2, characterized in that: The measurement steps of the recycling percentage R are: An arteriovenous blood temperature curve is generated according to the arterial blood temperature and venous blood temperature at the fistula; A temperature change pulse is injected into the artery and vein through dialysate, and the recirculation percentage is calculated based on the stress pulse portion of the temperature change pulse generated by the arteriovenous blood temperature curve.

4. The continuous body temperature automatic regulation method according to claim 1, characterized in that: Before or during dialysis, a target central body temperature change trend is set, and a target central body temperature change curve is generated according to the initial central body temperature and the target central body temperature change trend; During dialysis, the temperature of the arterial side and the venous side of the extracorporeal blood circulation circuit are collected in real time; During dialysis, the target venous blood temperature at the fistula at time t is calculated according to the target central body temperature curve; The target venous blood temperature at the fistula at time t is compensated for the heat loss in the pipeline to obtain the target dialysate temperature at time t.

5. The continuous body temperature automatic regulation method according to claim 4, characterized in that: Target venous blood temperature at fistula at time t Among them, T bt is the target central body temperature at time t on the target central body temperature curve, T artt is the arterial blood temperature at the fistula at time t.

6. The continuous body temperature automatic regulation method according to any one of claims 1 to 5, characterized in that: Set the upper and lower limits of the dialysate temperature. When the dialysate target temperature is higher than the upper limit of the dialysate temperature, the upper limit of the dialysate temperature is used as the dialysate target temperature; when the dialysate target temperature is lower than the lower limit of the dialysate temperature, the lower limit of the dialysate temperature is used as the dialysate target temperature.

7. A continuous body temperature automatic regulation system, characterized in that: It includes a dialysate temperature controller, an arterial temperature sensor for collecting the arterial side temperature in the extracorporeal blood circulation pipeline and a venous temperature sensor for collecting the venous side temperature; The signal output ends of the arterial temperature sensor and the venous temperature sensor are respectively connected to the corresponding signal input ends of the dialysate temperature controller; the dialysate temperature controller calculates the dialysate target temperature based on the arterial side temperature and the venous side temperature according to the continuous body temperature automatic adjustment method according to any one of claims 1-6, and adjusts the dialysate temperature according to the dialysate target temperature.

8. The continuous body temperature automatic regulation system according to claim 7, characterized in that: It also includes a heating module, which is connected to the dialysate temperature controller. The dialysate temperature controller controls the heating module to heat the dialysate so that the dialysate temperature is consistent with the dialysate target temperature.

Images