Patent US4291705A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4291705A Expired / Lapsed US ⏱️ 0.0 years remaining

Neuromuscular block monitor

Assignee: University of California, San Diego
•
Filing: 1979-09-10
•
Granted: 1981-09-29
•
Expires: 1999-09-10
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract To determine the degree of neuromuscular blockage, the apparatus of the invention electrically, supramaximally stimulates the motor nerve of a patient by stimulus means, applies the resulting electromyogram (EMG) produced by the muscle associated with that motor nerve and integrates the amplified EMG with respect to time. The integrated, amplified EMG is then displayed. In a preferred embodiment of the invention means are also provided for displaying the integrated, amplified EMG, taken after a muscle relaxant has been administered to the patient, as a ratio of a control EMG taken with the apparatus before the administration of the drug.

Inventors

  • 👤 John W. Severinghaus
  • 👤 Edwin M. Severinghaus

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 15:43
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/05; A61B5/103; A61B5/11; A61B5/1104; A61B5/1106; A61B5/24; A61B5/316; A61B5/389; A61B5/395; A61B2505/00; A61B2505/05

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 194 words
Apparatus for monitoring the neuromuscular transmission of a motor nerve and the muscle associated with the nerve in a patient, the apparatus comprising stimulator means for generating a plurality of electrical stimulus signals which are spaced apart by predetermined periods of time and for applying such stimulus signals to the motor nerve to supramaximally stimulate it, amplifier and detector means connected to the stimulator means, and including a pair of sensing electrodes adapted to be attached to the patient, for sensing the electromyogram (EMG) produced by the associated muscle as a result of the stimulating electrical signals and for amplifying the EMG, electronic integrator means connected to the amplifier and detector means for receiving each amplified EMG in response to each stimulus signal and for integrating it with respect to time over periods which fall between stimulus signals, control standard means connected to the integrator means for storing a representation of a first integrated EMG, comparator means connected to the integrator means for generating an output signal which is representative of the ratio of a select, integrated EMG and the first, integrated EMG, and means for displaying the output signal of the comparator means.
Claim 2
Dependent Claim 194 words
Apparatus for monitoring the neuromuscular transmission of a motor nerve and the muscle associated with the nerve in a patient, the apparatus comprising stimulator means for generating a plurality of electrical stimulus signals which are spaced apart by predetermined periods of time and for applying such stimulus signals to the motor nerve to supramaximally stimulate it, amplifier and detector means connected to the stimulator means, and including a pair of sensing electrodes adapted to be attached to the patient, for sensing the electromyogram (EMG) produced by the associated muscle as a result of the stimulating electrical signals and for amplifying the EMG, electronic integrator means connected to the amplifier and detector means for receiving each amplified EMG in response to each stimulus signal and for integrating it with respect to time over periods which fall between stimulus signals, control standard means connected to the integrator means for storing a representation of a first integrated EMG, comparator means connected to the integrator means for generating an output signal which is representative of the ratio of a select, integrated EMG and the first, integrated EMG, and means for displaying the output signal of the comparator means.
Claim 3
Dependent Claim 53 words
Apparatus as recited in claim 1 wherein the control standard means produce a reference signal representative of the integrated and stored first EMG, and wherein the comparator means include means for resetting the integrator means to a predetermined initial value whenever the integrated EMG output of the integrator means exceeds the reference signal.
Claim 4
Dependent Claim 58 words
Apparatus as recited in claims 1 or 2 wherein the comparator means generate an output signal which is representative of the ratio of the integrated, amplified EMG's obtained from a patient after the administration of a muscle relaxant drug to the first integrated EMG when taken with the monitoring apparatus before the administration of a muscle relaxant drug.
Claim 5
Dependent Claim 36 words
Apparatus as recited in claim 1 wherein the stimulator means comprise a mode control circuit for selectively producing either a single pulse, a rapid series of pulses, or a predetermined number of pulses at regular intervals.
Claim 6
Dependent Claim 22 words
Apparatus as recited in claim 1 wherein the amplifier and detector means further comprise a rectifier for passing only negative polarity EMG's.
Claim 7
Dependent Claim 19 words
Apparatus as recited in claim 1 wherein the integrating means integrates over a period of up to 8 milliseconds.
Claim 8
Independent Claim 101 words
A method of monitoring meuromuscular blockage in a patient comprising the steps of electrically, supramaximally stimulating a motor nerve of a patient before the administration of a muscle relaxant drug, detecting amplifying the resulting electromyogram (EMG) produced by the muscle associated with the stimulated motor nerve, integrating and holding the amplified EMG with respect to time to obtain an integrated control EMG, repeating the stimulating, amplifying, integrating and holding steps after the administration of a muscle relaxant drug to the patient to obtain a second integrated EMG, and displaying the ratio of the second integrated EMG to the integrated control EMG.
Claim 9
Independent Claim 101 words
A method of monitoring meuromuscular blockage in a patient comprising the steps of electrically, supramaximally stimulating a motor nerve of a patient before the administration of a muscle relaxant drug, detecting amplifying the resulting electromyogram (EMG) produced by the muscle associated with the stimulated motor nerve, integrating and holding the amplified EMG with respect to time to obtain an integrated control EMG, repeating the stimulating, amplifying, integrating and holding steps after the administration of a muscle relaxant drug to the patient to obtain a second integrated EMG, and displaying the ratio of the second integrated EMG to the integrated control EMG.
Claim 10
Dependent Claim 46 words
The method as recited in claim 7 comprising the further steps of repeating the stimulating, amplifying, and integrating steps after the administration of an antagonist drug to obtain a third integrated EMG and displaying the ratio of the third integrated EMG to the integrated control EMG.
Claim 11
Independent Claim 33 words
The method as recited in claims 7 or 8 wherein in performing the repeated integrating steps the rate of integration is adjusted to be reference to a function of the integrated control EMG.

References Cited (Backward Citations)

US2690178A Cited
US3364929A Cited
US3565080A Cited
US3513834A Cited
US3774593A Cited
US3898983A Cited
US3905355A Cited
US3916876A Cited
SU553968A1 Cited
US4148303A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-09-28 1985-03-30 1985-09-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-09-28 1989-03-30 1989-09-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-09-28 1993-03-30 1993-09-29 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag