CN111544719B - Method for estimating dynamic end-expiratory pressure in mechanical ventilation - Google Patents
Method for estimating dynamic end-expiratory pressure in mechanical ventilation Download PDFInfo
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/0003—Accessories therefor, e.g. sensors, vibrators, negative pressure
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/021—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes operated by electrical means
- A61M16/022—Control means therefor
- A61M16/024—Control means therefor including calculation means, e.g. using a processor
- A61M16/026—Control means therefor including calculation means, e.g. using a processor specially adapted for predicting, e.g. for determining an information representative of a flow limitation during a ventilation cycle by using a root square technique or a regression analysis
Abstract
The application provides a method for estimating dynamic positive end-expiratory pressure in mechanical ventilation, and mainly relates to the field of dynamic positive end-expiratory pressure research in mechanical ventilation. The present application uses an exhalation curve as a study object, and estimates the intra-alveolar positive pressure (positive end expiratory pressure 1, peep 1) at the moment before the inflection point and the assumed intra-alveolar positive pressure (positive end expiratory pressure 2, peep 2) if there is no inhalation force at the time of the actual exhalation flow rate of 0, based on the difference of the area under the curve of the actual exhalation curve and the imaginary trace curve and the compliance of the respiratory system. The application has the beneficial effects that: the application can provide the reference of the setting parameters of the breathing machine for medical staff when the breathing machine is used by patients, thereby leading the patients to achieve the best breathing effect by using the breathing machine and further improving the survival probability of the patients.
Description
Technical Field
The application mainly relates to the field of dynamic positive end expiratory pressure research in mechanical ventilation, in particular to a method for estimating dynamic positive end expiratory pressure in mechanical ventilation.
Background
As an effective means for artificially replacing the spontaneous ventilation function, a ventilator has been widely used in respiratory failure due to various reasons, anesthesia respiratory management during major surgery, respiratory support treatment and emergency resuscitation, and has taken a very important place in the field of modern medicine. The breathing machine is a vital medical device which can prevent and treat respiratory failure, reduce complications, save and prolong the life of patients.
In mechanical ventilation by using a ventilator, positive end-expiratory pressure is an index related to respiratory quality of a patient, but when the ventilator is clinically debugged, parameter setting can only be performed according to experience of a doctor or reaction of the patient, and no theoretical basis exists, so that the patient cannot be guaranteed to achieve the best ventilation effect under the assistance of the ventilator.
Disclosure of Invention
In order to solve the defects in the prior art, the application provides a method for estimating the dynamic positive end expiratory pressure in mechanical ventilation, which estimates the intra-alveolar positive pressure (positive end expiratory pressure 1, PEEPi) at the moment before inflection point according to the difference of the areas under the curves of an actual expiration curve and a fictive trace curve and the compliance of a respiratory system 1 ) And the assumed intra-alveolar positive pressure (end-expiratory positive pressure 2, peepi) if there is no inspiratory effort at an actual expiratory flow of 0 2 ) Thereby providing a reference for the usage parameter settings of the ventilator.
The application aims to achieve the aim, and the aim is achieved by the following technical scheme:
a method for estimating dynamic positive end-expiratory pressure in mechanical ventilation, comprising the steps of:
step one: define the expiration start time as T 0 The last moment before the inhalation effort occurs is T 1 Inspiratory effort slows lung recoil to T when airway expiratory flow is 0 2 ；
By T 1 The point is taken as a starting point, according to T 1 The curve evolution form of the natural expiration curve of the pre-patient is followed by tracing until the expiration flow is 0, and the 0 point is set as T 3 ；
Step two: t (T) 1 The point is the final point of the expiration action process, and at this time, the endogenous end expiratory positive pressure is set as PEEPi 1 ；
T 2 The point is the point at which the expiratory flow is 0 during inspiration effort, the end point of the expiratory phase, and if there is no inspiratory force at this time, the state of inflation of the lung is still greater than the functional residual air level of the natural end expiration, and the internal pressure of the lung is still greater than the internal pressure PEEP of the functional residual air level according to the state of inflation of the lung at this time, and this positive pressure is called the endogenous end expiratory positive pressure assumed at the end expiration phase and is PEEPi 2 ；
T 3 The point is the natural end expiration under the PEEP, and the intra-alveolar pressure is the same as the external pressure at the moment, and is PEEP;
step three: according to the expiration-time curve, the area under the curve is the amount of expired gas, i.e. the reduction of the lung volume; let T be 0 To T 1 The area under the curve between the two is S 1 ，T 0 To T 2 The area between them is S 2 ，T 0 To T 3 The area between them is S 3 ；
Step four: let its respiratory system compliance be C, PEEPi 1 ＝PEEP+(S 3 -S 1 )/C；
PEEPi 2 ＝PEEP+(S 3 -S 2 )/C。
Specifically, in the first step, T is used 1 The point is taken as a starting point, according to T 1 Natural exhalation curve of pre-patientIn the subsequent trace, a point at which the slope of the curve is significantly changed by starting the inhalation effort or starting the time-limited air supply should be selected as a trace start point, which is an inflection point of the curve, and a curve in which the inflection point is extended to 0 flow rate in the natural exhalation state is traced out from the trace of the curve before the inflection point.
Specifically, in the second step, T 2 The point is the point at which the expiratory flow is 0 during the inspiratory effort, and is the end point of the expiratory phase, when the intra-alveolar pressure should be the same as the external pressure PEEP, but because there is an inspiratory effort, not truly natural expiration to 0; assuming that the inspiration force does not exist, the expansion state of the lung is still greater than the functional residual capacity of the natural end expiration; according to the expansion state of the lung at this time, the pressure in the lung is still higher than the pressure PEEP in the lung at the position of functional residual gas, so the positive pressure is set as the endogenous end expiratory positive pressure envisaged at the end expiratory phase, and is PEEPi 2 。
Specifically, the respiratory system compliance C is measured by a ventilator.
Compared with the prior art, the application has the beneficial effects that:
the method takes an expiration curve as a study object, selects a point (inflection point) which causes the slope of the curve to be obviously changed when inspiration effort starts (or time-limited air supply starts) as a tracing starting point for the expiration curve of an incomplete expiration person, and traces the curve when the inflection point extends to 0 flow under the supposed natural expiration state according to the evolution form of the expiration curve before the inflection point. Based on the difference between the area under the curve of the actual expiration curve and the imaginary trace curve and the compliance of the respiratory system, the intra-alveolar positive pressure (end expiratory positive pressure 1, PEEPi) at the moment before the inflection point is estimated 1 ) And the assumed intra-alveolar positive pressure (end-expiratory positive pressure 2, peepi) if there is no inspiratory effort at an actual expiratory flow of 0 2 ) The two data are closer to the actual data, and can be used as a reference for medical staff to set parameters of the breathing machine when the breathing machine is used by a patient, so that the patient can achieve the best breathing effect by using the breathing machine, and the survival probability of the patient is improved.
Drawings
FIG. 1 is a graph of the expiratory flow time curve of the person with incomplete expiration, which is divided by each node;
fig. 2 shows the inflated state of the lung at each node of the person with incomplete exhalation according to the present application.
As shown in fig. 1, the gray curve is an air supply curve; the black curve is an expiration curve, and the black dotted line is an expiration curve under a virtual natural expiration state; t (T) 0 : an exhalation starting point; t (T) 1 Time of day: a point before the start of the inhalation; t (T) 2 Time of day: the time when the inspiration drive causes the expiration flow to be 0; t (T) 3 Time of day: the exhalation curve in the natural exhalation state is assumed to be at the time when the flow rate is 0.
S 1 ：T 0 To T 1 Area under the inter-expiratory flow time curve (expiratory volume); s is S 2 ：T 0 To T 2 Area under the inter-expiratory flow time curve (expiratory volume); s3: t (T) 0 To T 3 Area under the inter-expiratory flow time curve (expiratory volume).
As shown in figure 2, T 0 : an exhalation starting point; t (T) 1 Time of day: a front point of inspiration initiation (occurrence of inspiration force); t (T) 2 Time of day: inhalation drive causes the exhalation flow to be 0 time (inhalation force outward, arrow); t (T) 3 Time of day: the expiration curve in the natural expiration state (without inspiration force) is assumed to be at the time when the flow rate is 0.
S 1 ：T 0 To T 1 Area under the inter-expiratory flow time curve (expiratory volume); s is S 2 ：T 0 To T 2 Area under the inter-expiratory flow time curve (expiratory volume); s is S 3 ：T 0 To T 3 Area under the inter-expiratory flow time curve (expiratory volume).
Detailed Description
The application will be further described with reference to the accompanying drawings and specific embodiments. It is to be understood that these examples are illustrative of the present application and are not intended to limit the scope of the present application. Further, it will be understood that various changes and modifications may be made by those skilled in the art after reading the teachings of the application, and equivalents thereof fall within the scope of the application as defined by the claims.
As shown in FIGS. 1-2, the present application is directed to PEEPi 1 With PEEPi 2 The estimation method of (2) is as follows:
actual exhalation profile
Let the expiration start time be T 0 The last moment before inspiratory effort (inspiratory muscle begins to contract) occurs is T 1 (end-tidal point, airway still with outward flow), the inspiratory effort (inspiratory effort outward) slows the lung recoil to 0 airway expiratory flow, referred to as T 2 。
Envisaged extended trace
By T 1 The point is taken as a starting point, according to T 1 The curve evolution form of the natural expiration curve of the pre-patient is followed by tracing until the expiration flow is 0, and the 0 point is T 3 。
Pressure at each node
T 1 The point is the last point of the expiration action process, and no inspiration effort is participated at the moment, namely the endogenous end expiratory positive pressure is set as PEEPi 1 。
T 2 The point is the point at which the inspiration effort makes the expiration flow 0, is the end point of the expiration phase, and the intra-alveolar pressure should be the same as the external pressure PEEP, but the reason is that there is an inspiration force, not truly natural expiration to 0; if there is no inspiration force, the expansion state of the lung is still greater than the functional residual capacity of the natural end expiration; if it is assumed that there is no such inspiratory effort, the pressure should still be greater than the pressure in the lungs PEEP at the location of functional stuffiness, based on the state of inflation of the lungs at this time, this positive pressure is called the end-expiratory positive pressure assumed at the end of the expiratory phase, which is designated PEEPi 2 。
T 3 The point is the natural end expiration (functional residual capacity) under the PEEP, and the intra-alveolar pressure is the same as the external pressure at the moment, and is PEEP.
Volume between nodes
Since it is an exhalation-time curve, the area under the curve should be the amount of exhaled gas, i.e. the reduction in lung volume.
Let T be 0 To T 1 Area under curve (expiratory volume) between S 1 ，T 0 To T 2 The area between the two (exhale volume) is S 2 ，T 0 To T 3 The area between the two (exhale volume) is S 3 。
Calculation method
The respiratory system compliance is assumed to be C, and the breathing machine can be measured.
PEEPi 1 : from T according to the respiratory system compliance calculation formula 1 To T 3 The degree of change of volume is S 3 -S 1 ", the intra-alveolar depression degree is" PEEPi 1 -PEEP "; therefore, c= (S 3 -S 1 )/(PEEPi 1 -PEEP), i.e. PEEPi 1 ＝PEEP+(S 3 -S 1 )/C。
PEEPi 2 : from T according to the respiratory system compliance calculation formula 2 To T 3 The degree of change of volume is S 3 -S 2 ", the intra-alveolar depression degree is" PEEPi 2 -PEEP "; therefore, c= (S 3 -S 2 )/(PEEPi 2 -PEEP), i.e. PEEPi 2 ＝PEEP+(S3-S2)/C。
Claims (4)
1. A method for estimating a dynamic positive end-expiratory pressure in mechanical ventilation, comprising the steps of:
step one: define the expiration start time as T 0 The last moment before the inhalation effort occurs is T 1 Inspiratory effort slows lung recoil to T when airway expiratory flow is 0 2 ；
By T 1 The point is taken as a starting point, according to T 1 The curve evolution form of the natural expiration curve of the pre-patient is followed by tracing until the expiration flow is 0, and the 0 point is set as T 3 ；
Step two: t (T) 1 The point is the final point of the expiration action process, and at this time, the endogenous end expiratory positive pressure is set as PEEPi 1 ；
T 2 The point is the point at which the expiratory flow is 0 during inspiratory effort, the end point of the expiratory phase, assuming thisWhen there is no inspiration force, the expansion state of the lung is still larger than the functional residual capacity position of the natural end-expiration, and the internal pressure of the lung is still larger than the internal pressure PEEP of the lung at the functional residual capacity position according to the expansion state of the lung at the moment, and the positive pressure is called the endogenous end-expiration positive pressure envisaged at the end-expiration time phase and is PEEPi 2 ；
T 3 The point is the natural end expiration under the PEEP, and the intra-alveolar pressure is the same as the external pressure at the moment, and is PEEP;
step three: according to the expiration-time curve, the area under the curve is the amount of expired gas, i.e. the reduction of the lung volume; let T be 0 To T 1 The area under the curve between the two is S 1 ，T 0 To T 2 The area between them is S 2 ，T 0 To T 3 The area between them is S 3 ；
Step four: let its respiratory system compliance be C, PEEPi 1 ＝PEEP+(S 3 -S 1 )/C；
PEEPi 2 ＝PEEP+(S 3 -S 2 )/C。
2. The method of claim 1, wherein in the first step, T is used for estimating the dynamic positive end-expiratory pressure 1 The point is taken as a starting point, according to T 1 When the curve evolution form of the natural expiration curve of the patient is followed, the point at which the inspiration effort starts or the time-limited air supply starts to cause the slope of the curve to change significantly should be selected as the starting point of the curve, and the starting point is the inflection point of the curve, and the curve when the inflection point extends to the flow rate of 0 under the assumption of the natural expiration state is traced according to the curve evolution form of the expiration curve before the inflection point.
3. The method for estimating a dynamic positive end-expiratory pressure in mechanical ventilation according to claim 1, wherein in said step two, T 2 The point is the point at which the expiratory flow is 0 during the inspiratory effort, and is the end point of the expiratory phase, when the intra-alveolar pressure should be the same as the external pressure PEEP, but because there is an inspiratory effort, not truly natural expiration to 0; false, falseWhen the inspiration force does not exist, the expansion state of the lung is still larger than the functional residual capacity of the natural end expiration; according to the expansion state of the lung at this time, the pressure in the lung is still higher than the pressure PEEP in the lung at the position of functional residual gas, so the positive pressure is set as the endogenous end expiratory positive pressure envisaged at the end expiratory phase, and is PEEPi 2 。
4. The method of claim 1, wherein the respiratory compliance C is measured by a ventilator.
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| CN112535471B (en) * | 2020-11-06 | 2022-05-03 | 北京航空航天大学 | Method for estimating lung atelectasis characteristic based on static inspiratory pressure-volume curve of lung |
| CN112827030B (en) * | 2021-01-06 | 2023-02-28 | 北京谊安医疗系统股份有限公司 | Expiratory pressure automatic titration method and system based on expiratory airflow limitation index |
| CN113288113B (en) * | 2021-05-27 | 2023-02-28 | 湖南城市学院 | Method for online measuring and calculating respiratory tract air resistance and compliance of noninvasive positive pressure respirator |
| WO2023197112A1 (en) * | 2022-04-11 | 2023-10-19 | 深圳迈瑞生物医疗电子股份有限公司 | Ventilation apparatus and ventilation monitoring method |
| CN115804585B (en) * | 2023-02-08 | 2023-06-13 | 浙江大学 | Method and system for detecting high resistance of airway based on mechanical ventilation waveform |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5575283A (en) * | 1994-02-14 | 1996-11-19 | Siemens-Elema Ab | Device for determining an opening pressure in the lungs |
| US5632270A (en) * | 1994-09-12 | 1997-05-27 | Puritan-Bennett Corporation | Method and apparatus for control of lung ventilator exhalation circuit |
| CN103920215A (en) * | 2014-05-04 | 2014-07-16 | 湖南明康中锦医疗科技发展有限公司 | Method for supplying gas to patient through gas stream generator |
| CN109222978A (en) * | 2018-09-22 | 2019-01-18 | 广州和普乐健康科技有限公司 | A kind of respiratory effort detection method |
| CN110975087A (en) * | 2019-12-09 | 2020-04-10 | 武云珍 | Breath mechanics analysis method during inspiration triggering in mechanical ventilation |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9468398B2 (en) * | 2004-06-24 | 2016-10-18 | Convergent Engineering, Inc. | Method and apparatus for detecting and quantifying intrinsic positive end-expiratory pressure |
| EP1765442B1 (en) * | 2004-06-24 | 2017-08-02 | Convergent Engineering, Inc. | APPARATUS FOR NON-INVASIVE PREDICTION OF INTRINSIC POSITIVE END-EXPIRATORY PRESSURE (PEEPi) IN PATIENTS RECEIVING VENTILATORY SUPPORT |
| US8973578B2 (en) * | 2006-09-14 | 2015-03-10 | Politecnico Di Milano | Apparatus for respiratory support and non-invasive detection of alveolar derecruitment for patients suffering from respiratory failure |
-
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- 2020-05-11 CN CN202010391736.1A patent/CN111544719B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5575283A (en) * | 1994-02-14 | 1996-11-19 | Siemens-Elema Ab | Device for determining an opening pressure in the lungs |
| US5632270A (en) * | 1994-09-12 | 1997-05-27 | Puritan-Bennett Corporation | Method and apparatus for control of lung ventilator exhalation circuit |
| CN103920215A (en) * | 2014-05-04 | 2014-07-16 | 湖南明康中锦医疗科技发展有限公司 | Method for supplying gas to patient through gas stream generator |
| CN109222978A (en) * | 2018-09-22 | 2019-01-18 | 广州和普乐健康科技有限公司 | A kind of respiratory effort detection method |
| CN110975087A (en) * | 2019-12-09 | 2020-04-10 | 武云珍 | Breath mechanics analysis method during inspiration triggering in mechanical ventilation |
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