Showing papers on "Heartbeat published in 1983"

Respiration and heart rate monitoring apparatus

Abstract: A respiration and heart rate monitoring apparatus includes a mechanical-electric apparatus for detecting chest movements and electrodes for detecting electric impulses associated with heartbeat. A highly sensitive detector includes a transducer crystal mounted in bridge-like configuration on pair of spaced piers connected by at least one flexible beam member. The transducer crystal and electrodes may be connected to circuitry for producing indications of respiration and heart rate. The circuitry blocks detection of chest motion substantially coincident with the impulses associated with heartbeat to inhibit erroneous indications of respiration caused by chest motion due to heartbeat. The circuitry also may block small, single polarity signals to inhibit erroneous indications of respiration caused by muscle noise.

Dual frequency heart rate monitor utilizing doppler radar

Abstract: A heart rate monitor for use where direct contact with a patient cannot be made utilizes two continuous radio frequency (RF) signals, one of relatively low frequency and one of relatively high frequency directed toward the patient whose heart is to be determined. Doppler shifted signals are reradiated by the patient back to the monitor. The reradiated low RF signal has doppler components due to bodily motion caused by respiration and heartbeat. The reradiated high RF signal has doppler components due to patient bodily movement caused by respiration. Doppler components due to heartbeat if any, are of substantially lower value than those associated with the low RF signal. The heart rate monitor includes a difference amplifier which effectively subtracts the doppler signal associated with the high RF frequency from the doppler signal associated with the low RF frequency to obtain a signal which contains only components due to the heartbeat of the patient.

Fetal heartbeat doppler transducer

Abstract: A doppler transducer which is particularly well adapted for use in fetal heartbeat measurements is comprised of a piston type transducer with a pair of lenses, which together provide both a divergent acoustic pattern and a flat surface for good acoustic coupling between the transducer and the mother's abdomen.

Altered feeding response as a cause for the altered heartbeat rate and locomotor activity of schistosoma mansoni-infected biomphalaria glabrata

Abstract: Biomphalaria glabrata infected with Schistosoma mansoni for 33 days fed more often than unin- fected snails. Whereas uninfected snails had nocturnal increases in feeding, snails with a 33-day-old infection of S. mansoni fed as often during the day as in the night. Using direct observation and film analysis, we found that feeding increased the heartbeat rate and locomotor activity of B. glabrata. When snails were allowed to feed ad lib., infected snails had higher heartbeat rates than uninfected snails both during the day (P < 0.01) and the night (P < 0.001). However, when the snails were deprived of food for 24 hr, infected snails had slightly higher heartbeat rates than uninfected snails only during the day (P < 0.05). There was no difference between the heartbeat rates of feeding, infected snails and the heartbeat rates of uninfected snails that were starved for 8 hr, and then allowed to feed. Uninfected snails had nocturnal increases in heartbeat rate regardless of feeding schedule, but infected snails had greater nighttime heartbeat rate than daytime heartbeat rate only when they were not allowed to feed. Infected snails had less nocturnal locomotor activity than uninfected snails when feeding, but there was no difference between the locomotor activity of infected and uninfected snails when the snails were deprived of food for 24 hr. Absence of food also resulted in an increased nighttime to daytime ratio of locomotor activity of infected snails. These results suggest that the increased heartbeat rate and altered rhythms of heartbeat rate and locomotor activity in B. glabrata infected with S. mansoni for 33 days were caused by the altered feeding response of these snails.

Electrical therapy of cardiac arrhythmias.

Abstract: More than 30 years ago, Zoll1 demonstrated the life-saving application of external electrical stimulation of the arrested heart. Now he and his colleagues2 have improved on that technique. In this issue of the Journal, they show that even in this electronically sophisticated medical age, a simple approach may still have a place. But in the 30-year interval, particularly in the past four or five years, phenomenal developments in the electrical control of the heartbeat have occurred. Very advanced and complex dual-chamber (atrioventricular) pacing devices have been developed that permit maximal restoration of normal hemodynamic and electrical responses in patients with . . .

New heartbeat phenomenon, and the concept of 2-D optical turbulence.

Abstract: A new heartbeat phenomenon (HB2), produced when a laser beam travels vertically upward through a shallow pool of absorbing liquid, is described. The HB2 is compared with a previously reported similar heartbeat (HB1) obtained when a laser beam travels horizontally near and under the free surface of an absorbing liquid. The main difference between both phenomena is that the HB1 permits us to observe the transition to what we call 2-D optical turbulence, while the HB2 does not.

Activity monitor, power-on clear circuit

Abstract: A power-on clear circuit is disclosed with a repetitive reset output for use with a microprocessor having a "heartbeat" activity monitor. The reset output is repeated at specified intervals until the activity monitor is sensed, at which time the reset output is disabled until the activity monitor is no longer detected.

Heartbeat and blood pressure in terrestrial slugs

Abstract: Heart rate was measured in four species of terrestrial slugs. The effects of temperature, body weight, activity, and cardiac denervation on heart rate were established. Using a servo-null-balance s...

Apparatus and method for reduction in respiration artifact in pulmonary artery pressure measurement

Abstract: Apparatus is disclosed for deriving weighted values SHD i, DHD i and MHD i to respectively represent the systolic, diastolic and mean blood pressures for each heartbeat of a patient from the values S i , D i and M i that are the maximum, minimum and means blood pressures of the current heartbead; S i-1 , D i-1 and M i-1 that were the maximum, minimum and mean blood pressures for the previous heartbeat; SHD i-1, DHD i-1 and MHD i-1 that respectively represented the systolic, diastolic and means blood pressures of the previous heartbeat; and a constant K i that is a function, F, of the difference between M i and the mean pressure M i-1 of the previous heartbeat. The expressions for S i , D i , M i and K i are as follows: ##EQU1##

Automatic pulse rate trigger-source select circuit

Abstract: Disclosed herein is a circuit for automatically selecting between an ECG heartbeat signal source and a pressure/pulse signal source depending on which of the two sources is the most periodic between three successive heart beats. A pair of microprocessor internal timers commence a count-up cycle in response to a first detected heart beat from each of the two respective sources, after which count-down cycles are started in response to the next successive detected heart beats. The counting of the timers is then stopped in response to the third successive detected heart beats from the two sources and a comparison is provided to determine which of the two sources is most periodic, and should be used to trigger a heart rate monitor.

A method of and apparatus for estimating heartbeat rate

Abstract: A continuity detection method and apparatus for use in a system for monitoring a patient's EKG signal and estimat­ ing heartbeat rate including continuity detection apparatus for continuously monitoring electrical continuity between to EKG electrodes contacting the patient to inhibit the system from its measuring of heartbeat intervals whenever poor continuity is detected.

Drunken driving preventing device

Abstract: PURPOSE:To securely prevent drunken driving by judging whether a driver is drunk or not from both the detected result of an alcohol sensor and the detected result of the distribution of heartbeat, and prohibiting the starting of engine if said driver is in a drunken condition. CONSTITUTION:An oscillation circuit OSC1, which outputs a signal, is connected to a light emitting diode LD of a heartbeat detector 2, and an alcohol sensor ASE is formed by a semiconductor resistor SC, whose resistance value varies with the strength of alcohol. A main relay RL for prohibiting the start of engine is interposed between an ignition key switch IGS and an ignition coil. Any detected alcohol by checking the switch IGS is displayed on a cathode-ray tube display device CRT2, and an unusual distribution in the judging result of a step S55 is also displayed on the CRT2, and a speech synthesis device VGU is energized, to carry out warning with voice.

Medical impact wave injecting apparatus

Abstract: An instrument for therapeutic shock waves in which the shock waves are triggered in response to the patient's heartbeat cycle or to the patient's breathing cycle or both