Abstract:
Blood pressure cuff for measuring slender, normal and thick upper arms as well as thighs, characterized in that it comprises a number of sections (3-5, 3'-5') defining the width of the field acting around the upper arm or thigh at pressure measurement, which sections are connected via each their channel (6) to the force pump creating the pressure, and a throttle means (9) arranged to connect one or more channels with the air pump depending on the thickness of the arm or thigh.
Abstract:
A method and apparatus for determining the rate of flow of a liquid in a selected region of a body by nuclear magnetic resonance techniques. The method includes a sequence of applying a first magnetic pulse (B 1 (90°) ) effective to excite nuclear magnetic resonance of a chosen nucleus within the liquid preferentially in a slice of the body which includes the selected region. A period of time (to) is waited and then a second magnetic pulse (B 1 (90°) ) is applied which is effective to excite nuclear magnetic resonance of the nuclei preferentially in the slice, and the free induction decay signal is measured. The whole sequence is repeated for different values of the period of time (to). The values of the period of time (to) and the corresponding measured signals are then related to the rate of flow of the liquid through the slice.
Abstract:
A method and apparatus for producing two-dimensional, plan view images of in vivo blood flow networks using unique nuclear magnetic resonance (NMR) pulse sequences are disclosed. The method teaches the use of a pair of 90° selective pulses separated by a delay time optimized to provide images with enhanced blood flow contrast by discriminating against stationary media surrounding the blood flow path. For the instant method, two-dimensional images are compiled by the illustrative apparatus using a collection of NMR slice data, wherein each slice reflects a one-dimensional projection of NMR received signal data in a thin planar slab selected to be generally orthogonal to the primary blood flow network. Further alternative embodiments discuss the use of free induction decay (FID) signals, as well as single pulse and multiple pulse spin echo sequences.
Abstract:
Cardiac output is measured utilizing an indicator, such as saline, which alters blood resistivity, and an electrically calibrated conductivity cell positioned at the tip of a catheter. The catheter with the tetrapolar conductivity cell at the top is inserted into a blood vessel for current injection to develop a potential which is proportional to blood resistivity for inscribing the dilution curve occurring due to injection of the indicator, which curve is utilized to determine blood flow or cardiac output.
Abstract:
L'invention concerne un procédé de mesure de la pression sanguine d'un sujet à l'aide d'un sphygmomano mètre ayant un brassard (1) muni d'une chambre déformable (3) et d'un microphone (5). Après fixation du brassard (1) sur le bras du sujet et gonflage de la chambre (3) à une pression suffisante, on fait décroítre cette pression de façon discontinue par pas de décompressions ayant tous une même amplitude Δp. Dans une première phase où aucun son ayant une intensité supérieure à un premier seuil W₀ ne peut être détecté à l'aide du microphone (5), on effectue les pas de décompression à intervalles réguliers, toutes les 1,6 secondes par exemple. Dans une deuxième phase qui commence après la détection de deux premiers sons (S₄,S₅) dont l'intensité dépasse ledit seuil W₀, on effectue un pas de décompression à chaque apparition d'un nouveau son S₀, dont l'intensité dépasse un seuil W₁ associé audit son et déterminé en fonction de l'intensité d'au moins un des sons détectés précédemment.
Abstract:
An inflatable blood pressure cuff is volumetrically contiguous with a reservoir, and has a microphone mounted on the inside cuff surface. Electrocardiograph signals are obtained, and the cuff is first inflated, then incrementally deflated. At each pressure increment, and for a number of heart beats dependent on the subject's heart rate, data acquisition is gated based on cardiac R-waves. In particular, a first plurality of microphone signal samples are taken, approximately about the R-wave occurrence, and a second, larger and subsequent plurality is also taken. Sample combination techniques yield indices respectively representing noise and signal plus noise, and at least at the first instance when signal exceeds noise by a specified amount, a Korotkoff sound is deemed to have occurred, and systolic pressure is identified. Subsequent deflation and similar processing is utilized to detect diastolic pressure, which occurs when the Korotkoff sounds decrease rapidly or substantially cease.
Abstract:
A cardiovascular monitor comprises a watch casing, a timing circuit (3) in the watch casing for supplying timing signals, a transducer (2) associated with the watch casing for sensing arterial blood pulses and supplying an electric signal in dependence thereon, electrodes (7) associated with the watch casing for sensing electrocardiographic R-waves and supplying an electric signal in dependence thereon, a circuit (5) for deriving from the transducer signal and a timing signal an electric signal representing heartbeat rate, a circuit (4) for deriving from the electrode signal, the transducer signal and a timing signal an electric signal representing mean blood pressure, and a display (6) on the watch casing for displaying the time of day in dependence on a timing signal, heartbeat rate in dependence on the heartbeat rate signal, and mean blood pressure in dependence on the blood pressure signal. Alternatively, only the time of day and the heartbeat rate, or only the mean blood pressure may be displayed.
Abstract:
A probe for monitoring the blood pressure of a patient includes a light reflective diaphragm 4 deformable in response to the blood pressure. A single emitter light guide l0 is arranged off-set from the central axis of the diaphragm 4 and directs light at an off-axis region of the diaphragm. A pair of receiver light guides 8, l2 are arranged one on each side of the emitter light guide l0 so that the axes of the light guides lie in or adjacent the same plane as the centre of the diaphragm 4. Each receiver light guide 8, l2 receives light reflected from the diaphragm 4 in accordance with movement of the diaphragm 4.