US3898983A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device and method for detecting the degree of muscle relaxation of a medical patient
Assignee: Individual
•
Filing: 1973-10-03
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Granted: 1975-08-12
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Expires: 1993-10-03
Abstract
Abstract The system and method automatically indicate the degree to which the muscles of a surgical patient have been relaxed by the use of relaxant drugs, and control the dispensing of relaxant drugs to the patient. Electrical pulses are applied to the ulnar nerve between two points on an arm of the patient. This causes the fingers on that arm to clench. The clenching or flexing of the fingers is detected by an inflatable bladder which is placed in the patient''s hand. The patient''s fingers are held tightly against the surface of the bladder by an evacuatable enclosure so that when the fingers flex they squeeze the bladder. The resulting change in pressure of the gas in the bladder is detected either by a pressure meter or by a piezoelectric crystal which converts the pressure changes into electrical signals. The magnitude of the signals indicates the degree of muscle relaxation of the patient. The electrical signals are read on an electrical meter, or are recorded or are utilized to control a system for dispensing the relaxant drug to the patient. In the preferred embodiment of the invention, a burst of electrical pulses called tetanic stimulation is applied to the ulnar nerve. This creates a tetanic state in which the muscles flex the fingers continuously for about five seconds. A selected number of the resulting post-tetanic pulses from the bladder-detector are sampled and integrated with respect to time. If the integration value is above a pre-set value, then this indicates the need for further relaxant drugs, and a pre-determined dose of such a drug is automatically dispensed by a parenteral fluid dispensing system. If the integration value is below the pre-set level, this indicates satisfactory muscle relaxation, and no additional drugs are dispensed.
Inventors
- 👤 James O Elam
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:27
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/103; A61B5/05; A61B5/11; A61B5/1104; A61B5/1106; A61B5/22; A61B5/224; A61B5/225; A61B5/68; A61B5/6801; A61B5/6813; A61B5/6825; Y; Y10; Y10S; Y10S128/00; Y10S128/13
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
106 words
A relaxation detector device comprising a stimulator means for electrically stimulating selected muscles of a living being and causing said muscles to flex, transducer means adapted to be associated with at least one of said selected muscles for converting the movement of said muscle into a signal which is a function of the amount of said movement, and holding means for holding against non-flexing movement a part of the body which is moved when said muscles flex, said holding means comprising a flexible, thin-wall gas-tight container shaped to enclose said body part and having a granular material therein, and means for removing gas from said container.
Claim 2
Dependent Claim
106 words
A relaxation detector device comprising a stimulator means for electrically stimulating selected muscles of a living being and causing said muscles to flex, transducer means adapted to be associated with at least one of said selected muscles for converting the movement of said muscle into a signal which is a function of the amount of said movement, and holding means for holding against non-flexing movement a part of the body which is moved when said muscles flex, said holding means comprising a flexible, thin-wall gas-tight container shaped to enclose said body part and having a granular material therein, and means for removing gas from said container.
Claim 3
Dependent Claim
35 words
A device as in claim 1 in which said transducer means is pressure-sensitive and includes a fluid in a closed container, and means for converting said movement into changes in the pressure of said fluid.
Claim 4
Dependent Claim
51 words
A device as in claim 2 in which said container is a bladder with flexible walls and shaped to be gripped by the human hand, said stimulator is adapted to be connected to stimulate the ulnar nerve in a human arm, and said holding means is shaped to enclose said hand.
Claim 5
Dependent Claim
22 words
A device as in claim 2 including pump means for initially pumping the pressure in said fluid up to a predetermined level.
Claim 6
Dependent Claim
43 words
A device as in claim 2 in which said transducer means includes a means for converting the pressure in said container into a corresponding electrical signal, amplifier means for amplifying said corresponding signal, and meter means for indicating the magnitude of said signal.
Claim 7
Dependent Claim
35 words
A device as in claim 1 in which said transducer means is pressure-sensitive and includes a fluid in a closed container, and means for converting said movement into changes in the pressure of said fluid.
Claim 8
Dependent Claim
33 words
A device as in claim 6 including means for selecting a pre-determined number of said signals, integrating the selected signals with respect to time, and producing a signal proportional to the integration product.
Claim 9
Dependent Claim
29 words
A device as in claim 7 iNcluding a level detector means for detecting and indicating the condition in which said integration product signal reaches and/or passes a predetermined level.
Claim 10
Independent Claim
61 words
A method of detecting the degree of relaxation of a medical patient, said method comprising applying electrical stimulation signals to cause post-tetanic twitch of at least one selected muscle of said patient, converting the post-tetanic twitches into corresponding tetanic signals, and converting the magnitude of a train of said signals into a signal indicating the degree of relaxation of said patient.
Claim 11
Independent Claim
61 words
A method of detecting the degree of relaxation of a medical patient, said method comprising applying electrical stimulation signals to cause post-tetanic twitch of at least one selected muscle of said patient, converting the post-tetanic twitches into corresponding tetanic signals, and converting the magnitude of a train of said signals into a signal indicating the degree of relaxation of said patient.
Claim 12
Dependent Claim
31 words
A method as in claim 9 including the step of integrating a plurality of said post-tetanic signals and comparing the integration product with a standard to determine the degree of relaxation.
Claim 13
Dependent Claim
82 words
A relaxation detector device comprising a stimulator means for electrically stimulating selected muscles of a living being and causing post-tetanic flexing of said muscles, transducer means adapted to be associated with at least one of said selected muscles for converting the movements of said muscle into signals the magnitude of each of which is a function of the amount of said movement, and means for converting the magnitude of a train of said signals into a signal indicating the degree of relaxation.
Claim 14
Dependent Claim
82 words
A relaxation detector device comprising a stimulator means for electrically stimulating selected muscles of a living being and causing post-tetanic flexing of said muscles, transducer means adapted to be associated with at least one of said selected muscles for converting the movements of said muscle into signals the magnitude of each of which is a function of the amount of said movement, and means for converting the magnitude of a train of said signals into a signal indicating the degree of relaxation.
Claim 15
Independent Claim
86 words
A method of detecting the degree of relaxation of a medical patient, said method comprising enclosing a portion of the body of said patient in a flexible-walled container with air-tight walls and granular material between the walls, evacuating air from said granular material to form a hard casing around said body portion, applying electrical stimulation signals to cause at least one selected muscle of said body portion of said patient to flex, and using the resulting flexing of said muscle to indicate said degree of relaxation.
Claim 16
Independent Claim
86 words
A method of detecting the degree of relaxation of a medical patient, said method comprising enclosing a portion of the body of said patient in a flexible-walled container with air-tight walls and granular material between the walls, evacuating air from said granular material to form a hard casing around said body portion, applying electrical stimulation signals to cause at least one selected muscle of said body portion of said patient to flex, and using the resulting flexing of said muscle to indicate said degree of relaxation.
Claim 17
Dependent Claim
66 words
A method as in claim 12 in which the selected muscles include those which cause the fingers of the hand of said patient to close, and including the steps of placing an inflated bladder in said hand, and converting the change of pressure in said bladder, upon the closing of said fingers around said bladder, into said indication signal, said enclosing step comprising enclosing said hand.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |