← Back to Patent Explorer
US5099841A Expired / Lapsed US ⏱️ 0.0 years remaining

Measurement of the composition of blood

Assignee: Instrumentarium Oyj
•
Filing: 1990-02-05
•
Granted: 1992-03-31
•
Expires: 2010-02-05
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The invention relates to a method for synchronizing an optical arterial pulse signal (2, 3, 4), obtained by passing electromagnetic radiation through a tissue, with a detected signal (1) obtained from heartbeat. The delays of optical arterial pulses in relation to corresponding heartbeats are used to set up a time lapse, during the course of which there must appear an arterial pulse acceptable in the determination of blood composition. The position of time lapse in relation to detected heartbeat is repeatedly determined while continuing measurements from the obtained optical pulses occurring during the time lapse.

Inventors

  • 👤 Erkki O. Heinonen
  • 👤 Esa J. Tuulari
  • 👤 Mona Gronstrand

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 07:40
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/24; A61B5/316; A61B5/318; A61B5/346; A61B5/349; A61B5/352

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 209 words
A method for synchronizing an arterial signal with a heartbeat signal so that blood composition can be accurately determined by analysis of the arterial signal, said arterial signal being obtained by passing electromagnetic radiation through tissue at location removed from that of the heart and being pulse-like in nature as a result of the pulsatile movement of blood through the tissue by the heartbeat of the heart, said method comprising the steps of: detecting the occurrence of an identifiable aspect of a heartbeat signal; ascertaining a point in time at which a pulse occurs in the arterial signal following the occurrence of an identifiable aspect of a given heartbeat signal; establishing a time period which includes said pulse in the arterial signal, said time period commencing after an interval following the occurrence of the identifiable aspect of the heartbeat, the commencement and conclusion of the period of time respectively preceding and succeeding the point in time by predetermined amounts; accepting arterial signals appearing within said time period for analysis to determine blood composition; repeating the ascertainment of the point in time for heartbeat signals occurring subsequent to the given heartbeat signal; and re-establishing the time period with respect to the heartbeat signal as a result of said subsequent ascertainment.
Claim 2
Independent Claim 209 words
A method for synchronizing an arterial signal with a heartbeat signal so that blood composition can be accurately determined by analysis of the arterial signal, said arterial signal being obtained by passing electromagnetic radiation through tissue at location removed from that of the heart and being pulse-like in nature as a result of the pulsatile movement of blood through the tissue by the heartbeat of the heart, said method comprising the steps of: detecting the occurrence of an identifiable aspect of a heartbeat signal; ascertaining a point in time at which a pulse occurs in the arterial signal following the occurrence of an identifiable aspect of a given heartbeat signal; establishing a time period which includes said pulse in the arterial signal, said time period commencing after an interval following the occurrence of the identifiable aspect of the heartbeat, the commencement and conclusion of the period of time respectively preceding and succeeding the point in time by predetermined amounts; accepting arterial signals appearing within said time period for analysis to determine blood composition; repeating the ascertainment of the point in time for heartbeat signals occurring subsequent to the given heartbeat signal; and re-establishing the time period with respect to the heartbeat signal as a result of said subsequent ascertainment.
Claim 3
Dependent Claim 29 words
The method according to claim 1 further defined as repeating the ascertainment of the point in time for each arterial signal having a pulse appearing within said time period.
Claim 4
Dependent Claim 30 words
The method according to claim 1 further defined as averaging the occurrences of the pulses in the arterial signals for a plurality of heartbeats in ascertaining the point in time.
Claim 5
Dependent Claim 17 words
The method according to claim 1 further defined as maintaining the duration of the time period constant.
Claim 6
Dependent Claim 16 words
The method according to claim 1 further defined as altering the duration of the time period.
Claim 7
Dependent Claim 32 words
The method according to claim 1 further defined as altering the predetermined amount of time by which the commencement or conclusion of the time period precedes or succeeds the point in time.
Claim 8
Dependent Claim 32 words
The method according to claim 4 further defined as altering the predetermined amount of time by which the commencement or conclusion of the time period precedes or succeeds the point in time.
Claim 9
Dependent Claim 32 words
The method according to claim 5 further defined as altering the predetermined amount of time by which the commencement or conclusion of the time period precedes or succeeds the point in time.
Claim 10
Dependent Claim 28 words
The method according to claim 1 further defined as determining the occurrence of an identifiable aspect of the heartbeat signal by detecting an EKG signal of the heart.
Claim 11
Dependent Claim 32 words
The method according to claim 1 further defined as one for determining blood composition and as including the step of analyzing arterial signals occurring within the time period to determine blood composition.

References Cited (Backward Citations)

US4224948A Cited
US4934372A Cited
US4928642A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-03-31 1995-09-30 1996-03-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-03-31 1999-09-30 2000-03-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-03-31 2003-09-30 2004-03-31 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag