Abstract:
A defibrillator/monitor (10) is disclosed employing a motion detection circuit 18 and control and processing circuit (20) that cooperatively detect motion at a patient-electrode interface. In that regard, an impedance measurement circuit (24) produces an output indicative of the impedance of the interface. This output is then processed by a number of filter elements before being analyzed by a motion detection routine (52). The motion detection routine includes subroutines (62 and 64) that compare the impedance against distinct upper and lower limits and then monitor the time at which the signal is above and below the limits. Basically, motion is indicated if the signal undergoes relatively large variations for a short time, or smaller variations for a longer time. A third motion clear subroutine (66) is used to determine when motion is no longer detected. Finally, a similar scheme (102) is employed to quickly restore the various filter elements after saturation.
Abstract:
An internal defibrillation electrode assembly (10) is disclosed including a disposable electrode (12) and a reusable handle (14). The electrode includes an electrode spoon (16), a shaft (18), and a barrier sleeve (20). The handle includes a handle body (58), electrical cable (60), sleeve connector (62), and electrical connector (64). The handle has a dagger-style configuration that makes the electrode assembly easy to use and is further constructed to allow the electrode to be quickly and reliably attached. In that regard, during assembly, a bayonet (32) on the shaft of the electrode is engaged in a bayonet receptacle (68) of the handle. The sleeve is then pulled over the handle to form a barrier between the handle and the environment. After the electrode assembly is used, the sleeve is removed from the handle, the electrode disengaged from the handle, and the electrode disposed of. After attaching a new electrode, the handle is then ready for immediate service. The handle can also be used with a reusable electrode that does not include a barrier sleeve. To that end, the handle is constructed to exhibit a relatively long life when subjected to repeated steam sterilization.
Abstract:
A defibrillator (20) designed to determine and display (a) the current which is anticipated to be provided to a patient by a defibrillation pulse generated by the defibrillator (20) when the former is to be provided in the form of an energy dose (46, 44) and (b) the energy which is anticipated to be provided to a patient by a defibrillation pulse generated by the defibrillator (20) when the former is to be provided in the form of a current dose (46, 42). The defibrillator (20) is also designed to determine and display how changes in the transthoracic impedance ( 70 ) of the patient will change (1) the magnitude of the selected energy level of the defibrillation pulse when defibrillator is in the energy dose mode and (2) the magnitude of the selected current level of the defibrillator pulse when the defibrillator is in the current dose mode.
Abstract:
A defibrillator/monitor (10) is disclosed employing a message processing routine (60) that controls the way in which information from a plurality of sensing circuits (28) is communicated to an attending physician by output devices (30). In that regard, each of the various conditions monitored by the sensing circuits has a priority associated therewith. Each condition may be associated with one or more of five different types of messages: an initial display message, steady state display message, initial sound message, steady state sound message, and display icon message. The different messages, like the different conditions, may also be prioritized. The particular message or messages produced by the output devices in response to a particular set of conditions is then dependent upon the relative prioritization of the conditions and messages as evaluated by a microcomputer (18) in accordance with the routine.
Abstract:
A defibrillation training system (10) is disclosed for use in training individuals in the proper positioning of defibrillation electrodes on a patient. The system includes a pair of training electrodes (12), each of which includes a permanent magnet (30). The training electrodes are attached to a manikin (14) at two electrode placement sites (42 and 44) provided with arrays (46 and 48) of Hall-effect sensors. The magnetic field produced by the permanent magnet in each electrode is sensed by the corresponding array, allowing an electrode placement monitor (16), attached to the manikin, to determine the electrodes' positions. The placement monitor then determines whether any adjustments in the electrodes' positions are required and prompts the individual being trained accordingly.
Abstract:
A training electrode for use in training emergency personnel in electrocardiogram (EKG) defibrillation and monitoring is disclosed. An adhesive pad is fixedly attached to a connector comprising a connecting post and a connecting arm. Attached to the connecting arm is an electrical cable with a female-type adaptor at its distal end for connection to an electrocardiogram simulation signal generator. The connecting post inserts into a female-type adaptor from a defibrillator/monitor cable lead originating from a defibrillator/monitor. A detachable backing covers an adhesive surface of the adhesive pad such that the training electrode may be reused. Further, a training method is disclosed using the training electrode of the present disclosure and incorporating existing CPR mannequins and EKG simulation signal generators.
Abstract:
In transmittance and reflectance oximetry, LEDs (40, 42) are typically employed to expose tissue to light at two different wavelengths. The light transmitted through, or reflected by, the tissue is received by a detector (38) where signals proportional to the intensity of light are produced. These signals are then processed by oximeter circuitry (14, 16) to determine oxygen saturation, pulse rate, and perfusion. Displays (20) are provided including a display (132, 134) of the change in the oxygen saturation during a specified interval. This display may include first (132) and second (134) trend indication displays that indicate when the oxygen saturation has either been increasing or decreasing at a rate in excess of some predetermined level. Preferably, these displays are triangular, upwardly and downwardly directed light-emitting diodes. A digital display (138) of the change in oxygen saturation may also be provided. A second type of display included provides pulse and perfusion information, with the perfusion being displayed as a logarithmic function of the actual perfusion. This display comprises an aligned array of light-emitting diodes (136) with the number of light-emitting diodes lit at any one time being logarithmically proportional to the magnitude of the perfusion. The display is automatically scaled to produce a full-scale display when the peak perfusion exceeds some predetermined level.
Abstract:
A battery pack (28) for a portable defibrillator (30). The battery pack has a latch (34) that is biased in an extended position. When the battery pack is inserted into a battery well (30) in the portable defibrillator, the latch automatically latches into a slot (124) to secure the battery pack in the battery well. Ridges (112) are provided on the floor (108) of the battery well to reduce the friction between the battery pack and the floor of the well as the battery pack is inserted into the defibrillator. A ridge (38) is also provided around the periphery of the top (36) of the battery pack to reduce the friction between the battery pack and the ceiling of the battery well. A right wall (44) of the battery pack is inclined from vertical so that a cross section of the battery pack is trapezoid in shape. The asymmetric cross section prevents the battery pack from being incorrectly inserted into the battery well. The disclosed battery pack construction simplifies the replacement of the battery pack in the portable defibrillator.