Abstract: The invention is a method of automatically adjusting an electrode array to the neural characteristics of an individual patient. By recording neural response to a predetermined input stimulus, one can alter that input stimulus to the needs of an individual patient. A minimum input stimulus is applied to a patient, followed by recording neural response in the vicinity of the input stimulus. By alternating stimulation and recording at gradually increasing levels, one can determine the minimum input that creates a neural response, thereby identifying the threshold stimulation level. One can further determine a maximum level by increasing stimulus until a predetermined maximum neural response is obtained.

Abstract: An instrument is described for assisting a rescuer in the proper administration of CPR. A sensor detects movement of the chest caused by ventilation. The sensor signals are processed to produce a control signal representative of the effectiveness of the ventilation. A lung icon is displayed in the outline shape of human lungs and the outline is displayed filled to a level which indicates the effectiveness of the ventilation.

Abstract: An implantable medical device such as a cardiac pacemaker or implantable cardioverter/defibrillator with the capability of storing body temperature measurements taken periodically and/or when triggered by particular events.

Abstract: There is provided a wearable defibrillator that includes a first sensor adapted to sense a cardiac related parameter, a second sensor adapted to sense breathing, a controller adapted to produce a signal upon determining a cardiac arrest and a defibrillating subunit adapted to provide a defibrillation energy upon receiving the signal from the controller. There is also provided a method of defibrillating that includes sensing a cardiac related parameter; sensing breathing; and triggering a defibrillation energy upon determining a cardiac arrest. There is further provided a wearable defibrillator that includes a first sensor adapted to sense a cardiac related parameter; a controller adapted to produce a signal upon determining a cardiac arrest; a transmitter adapted to send a signal indicative of a cardiac arrest to a remote location; and a defibrillation subunit adapted to trigger a defibrillation upon being activated from a remote location.

Abstract: A wearable defibrillator consists of a vest (or belt) which is worn by the patient. The device monitors the patient's ECG with sensing electrodes and can monitor other patient conditions and in appropriate cases can treat certain conditions. An accelerometer(s) in the wearable defibrillator can allow for the device to determine the position, movements, forces applied to the patient, and/or the device. The device can use a least one patient motion detector generating a signal indicative of patient activity. Analysis of the signal can be indicative of patient activity appropriate for treatment or indication of device condition.

Abstract: A medical device is disclosed that includes one or more treatment electrodes, one or more sensors, and one or more controllers connected to the one or more treatment electrodes and one or more sensors. The medical device also includes one or more response mechanisms connected to the one or more controllers. The one or more controllers are configured to receive input from the one or more response mechanism and are also configured to determine whether a patient wearing the medical device actuated the one or more response mechanisms based, at least in part, on the input received from the one or more response mechanisms. In some disclosed embodiments, the medical device is a wearable defibrillator.

Abstract: Embodiments include cardiac information and activity information association systems, apparatus, and methods. An apparatus embodiment includes a cardiac sensor adapted to generate cardiac information descriptive of cardiac functioning of a patient, an activity sensor adapted to generate activity information indicating physical activity of the patient, a processing element adapted to detect a cardiac anomaly based on the cardiac information, an information association element adapted to generate associated cardiac/activity information during the cardiac anomaly, and a data storage apparatus adapted to store the associated cardiac/activity information.

Abstract: An implantable device (100) having an electronic component (110) and a biologic materials component (130). The biologic materials component has target cells in a matrix that interfaces the electronic component with the surrounding environment.

Abstract: An embodiment of the invention is a method for recommending actions to be taken during resuscitation of a patient. Input signals related to the resuscitation are received during the resuscitation. The input signals are processed to generate output signals based on the input signals and predetermined criteria. The output signals are representative of the actions to be taken and are provided for further action.

Abstract: The presence of a cardiac pulse in a patient is determined by evaluating physiological signals in the patient. In one embodiment, a medical device evaluates optical characteristics of light transmitted into a patient to ascertain physiological signals, such as pulsatile changes in general blood volume proximate a light detector module. Using these features, the medical device determines whether a cardiac pulse is present in the patient. The medical device may also be configured to report whether the patient is in a VF, VT, asystole, or PEA condition, in addition to being in a pulseless condition, and prompt different therapies, such as chest compressions, rescue breathing, defibrillation, and PEA-specific electrotherapy, depending on the analysis of the physiological signals. Auto-capture of a cardiac pulse using pacing stimuli is further provided.

Abstract: An external defibrillator is described which maintains the durations of phases of a multiphasic shock waveform within or below desired limits. As the duration of a waveform increases for patients of increased patient impedance, the durations of the phases of a multiphasic shock waveform also increase. Before a maximum duration limit is exceeded, the defibrillator adds another phase to the multiphasic waveform which brings the durations of the phases within the desired range or below a maximum duration limit. Both the number of shock phases and the individual phase durations can be controlled in response to measured patient impedance.

Abstract: An exemplary method includes detecting fibrillation, measuring impedance of a defibrillation circuit that includes myocardial tissue, determining one or more defibrillation shock parameters based at least in part on the impedance, delivering a defibrillation shock using the one or more defibrillation shock parameters and, if the shock was unsuccessful, adjusting a membrane time constant and determining one or more new defibrillation shock parameters based at least in part on the adjusted membrane time constant. Various other exemplary methods are disclosed as well as various exemplary devices, systems, etc.

Abstract: Certain embodiments of the present invention disclose an implant with electrode line connections for the connection of intracardial and/or epicardial electrode lines, wherein the electrode line connections have together at least three electrical contacts of which at least one is associated with a right-ventricular electrode and another is associated with a left-ventricular electrode, an impedance determining unit (IMP) which has a current or voltage source (I) and a measuring device (U) for a corresponding voltage or current measurement operation, which is connected to the electrical contacts and possibly a housing electrode of the implant, in such a way as to afford a tri- or quadrupolar impedance measuring arrangement which includes exclusively ventricular electrodes and in addition possibly the housing electrode, wherein the impedance measuring arrangement produces impedance measurement values and is connected to an evaluation unit (EVAL) and the evaluation unit (EVAL) is adapted to ascertain a minimum of

Abstract: A heart stimulation system comprises an electrode lead comprising at least one stimulation electrode a stimulation pulse generator adapted to generate electric stimulation pulses and being connected to said electrode lead for delivering electric stimulation pulses to at least one chamber of a heart via said stimulation electrode, and a control unit that is connected to said stimulation pulse generator. The electrode lead is a coronary sinus lead adapted to be placed inside the coronary sinus of a human heart and comprises an ultrasonic transducer that is adapted to measure a velocity of blood flow across a mitral valve of a human heart and that is placed on said coronary sinus lead such that the ultrasonic transducer is placed in the coronary sinus or the great cardiac vein when the coronary sinus lead is in its implanted state.

Abstract: An apparatus (300, 400) and method operable to guide responders, via audible prompts and visual cues, through the proper procedures to be applied to a patient during a cardiac arrest. An embodiment of the present invention advantageously makes the ACLS procedures, such as types and dosages of medications to administer, and sequence of performing actions (such as cardiac pulmonary resuscitation (CPR)) on the patient easier to acknowledge and follow. An exemplary embodiment of the present invention (300) can be located on a conventional hospital crash cart which stores the emergency equipment and medications, or can be hardware and application software, the application software being loadable and loaded into computer hardware (200).

Abstract: Methods, systems and computer program products for reducing a risk of pulseless electrical activity (PEA) include detecting a first post-defibrillation blood flow of a subject and detecting a second post-defibrillation blood flow of the subject after the first post-defibrillation blood flow. If the first post-defibrillation blood flow of the subject is above a first threshold value and the second post-defibrillation blood flow is below a second threshold value, a plurality of electrical pulses that reduces a risk of PEA.

Abstract: A cardiac rhythm management (CRM) system provides for post-myocardial infarction (MI) therapy with closed-loop control using one or more ultrasound transducers sensing one or more ultrasound signals indicative of cardiac dimensions. Cardiac size parameters are produced using the one or more ultrasound signals to represent, for example, cardiac chamber diameter, cardiac chamber volume, cardiac wall thickness, infarct size, and degree of change in any of these parameters over time or between measurements. In various embodiments, such cardiac size parameters provide for titration, safety check, and acute optimization of the post-MI therapy.

Abstract: An elastic framework configured to be positioned around a portion of the heart has a plurality of first regions and a plurality of second regions positioned relative to the first regions. The framework allows for the positioning of the first regions and second regions adjacent the outer surface of the heart and is structured so that the regions experience different movement effects in response to expansion and contraction of the heart. A sensor network having at least one motion sensor system associated with one of the first regions and second regions is associated with the framework. The motion sensor system outputs data responsive to the relative movement effects of the first and second regions. A communications system in communication with the sensor network provides for the transmission of motion data to a location remote from the framework.

Abstract: Control of defibrillation therapy delivered by implantable medical devices (IMDs) using hemodynamic sensor feedback is disclosed. The hemodynamic sensor feedback allows for increased control over application of atrial defibrillation therapy. Specifically, the therapy is delivered when a fibrillation episode results in a discrete loss of hemodynamic function. Defibrillation therapy is thus withheld for hemodynamically benign arrhythmias.

Abstract: A system and method for assessing pulmonary performance through transthoracic impedance monitoring is described. Transthoracic impedance measures are directly collected through an implantable medical device. The transthoracic impedance measures are correlated to pulmonary functional measures relative to performance of at least one respiration cycle. The transthoracic impedance measures are grouped into at least one measures set corresponding to one of an inspiratory phase and an expiratory phase. The at least one transthoracic impedance measures set are evaluated to identify a respiratory pattern relative to the inspiratory phase or the expiratory phase to represent pulmonary performance.

Abstract: Assessing symptomatic and asymptomatic physiologic changes due to chronic heart failure involves apparatus and methods for gauging degradation and possible improvement using automated measurement of inter-ventricular conduction time, both alone and in combination with other automated physiologic tests. Conduction times increase due to the greater distance a wavefront must traverse as a heart enlarges. Analysis of conduction time can be used to verify the occurrence of cardiac remodeling due to heart failure as well as beneficial reverse remodeling due to successful heart failure therapy delivery. Patient activity level(s) and presence/increase in pulmonary fluids can also be used to automatically determine changes in heart failure status and/or predict hospitalization. Conduction time is monitored between electrodes positioned in the left and right ventricles of the heart via endocardial or epicardial electrodes.

Abstract: A technique utilizing an endolymphatically implanted lead having one or more electrodes that may be used for sensing cardiac activity and/or delivering cardiac electrical stimulation by an implantable cardiac device. An electrode disposed in the thoracic duct is in close proximity to the left ventricle and generates an electrogram especially suitable for ischemia detection and/or discriminating between ventricular tachycardias and supraventricular tachycardias.

Abstract: A self-powered pacemaker uses the variations of blood pressure inside the heart or a major artery to create a periodic change in the magnetic flux inside a coil. The pressure variations compress a bellows carrying a magnet moving inside a coil. The inside of the bellows is evacuated to a partial or full vacuum, and a spring restores the bellows to the desired equilibrium point, acting against the blood pressure. The current pulses are stored in a capacitor. Eliminating the battery allows dramatic miniaturization of the pacemaker to the point it can be implanted at the point of desired stimulation via a catheter. The invention includes means of compensating for atmospheric pressure changes.

Abstract: Cardiac systems and methods using ECG and blood information for arrhythmia detection and discrimination. Detection circuitry is configured to produce an ECG. An implantable blood sensor configured to produce a blood sensor signal is coupled to a processor. The processor is coupled to the detection and energy delivery circuitry, and used to evaluate and treat cardiac rhythms using both the cardiac electrophysiologic and blood sensor signals. The blood sensor is configured for subcutaneous non-intrathoracic placement and provided in or on the housing, on a lead coupled to the housing, and/or separate to the housing and coupled to the processor via hardwire or wireless link. The blood sensor may be configured for optical sensing, using a blood oxygen saturation sensor or pulse oximeter. A cardiac rhythm may be evaluated using the electrocardiogram signal and the blood sensor signal, and tachyarrhythmias may be treated after confirmation using the blood sense signal.

Abstract: A cardiac rhythm management device in which an accelerometer is used to detect diaphragmatic or other skeletal muscle contraction associated with the output of a pacing pulse. Upon detection of diaphragmatic contraction, the device may be configured to automatically adjust the pacing pulse energy and/or pacing configuration.

Abstract: A system and method for monitoring and controlling the therapy of a cardiac rhythm abnormality victim at a remote site by proving immediate access to a medical professional at a central station. The method comprises the steps of: (1) providing a plurality of electrodes for receiving cardiac signals generated by the victim and for the application of electrical pulses to the victim at a remote site; (2) transmitting the signals from the remote site to a central station; (3) receiving the signals at the central station and displaying them for the medical professional; (4) selecting whether to delivery defibrillation or pacing therapy to the victim based on the medical professional's analysis of the signals (5) transmitting the selection results to the remote site; and (6) receiving the selection results at the remote site and applying the selected therapy to the victim.

Abstract: An implantable medical device includes a controlling device for transmitting a first series of command signals, the controlling device comprising a connector block, a first lead body including at least one electrical lead, and a hermetic encasement. The hermetic encasement includes a housing defining an interior space, an electronic network housed within the interior space and configured to receive the first set of command signals from the controlling device and output a second series of command signals based on the first set of command signals, a first set of one or more feedthrough terminals extending through the housing and directly coupling the electronic network to the connector block, and a second set of one or more feedthrough terminals extending through the housing and directly coupling the electronic network to the first lead body.

Abstract: An implantable medical device and associated method for automatically generating morphology templates during fast cardiac rhythms, confirming a provisional template as a confirmed template, and using the confirmed template to classify subsequent detected arrhythmias. A provisional SVT template may be created during a fast ventricular rate and activated as a confirmed SVT template upon verification that the fast rate was due to an SVT. The confirmed SVT template may be used to discriminate SVT from VT/VF.

Abstract: Methods and apparatus are provided for minimizing the inherent time delays within external defibrillators. The methods and apparatuses utilize timing schemes for initiation and completion of charging of an energy storage device of an external defibrillator, measuring one or physical parameters of the patient and conducting a physiology analysis of the patient. The initiation and completion of one or more of these activities are arranged so that the energy storage device is charged to a desired level and available for a defibrillation shock to the patient with minimal delay after activation of the external defibrillator.

Abstract: An arrhythmia discrimination device and method involves receiving electrocardiogram signals and non-electrophysiologic signals at subcutaneous locations. Both the electrocardiogram-signals and non-electrophysiologic signals are used to discriminate between normal sinus rhythm and an arrhythmia. An arrhythmia may be detected using electrocardiogram signals, and verified using the non-electrophysiologic signals. A detection window may be initiated in response to receiving the electrocardiogram signal, and used to determine whether the non-electrophysiologic signal is received at a time falling within the detection window. Heart rates may be computed based on both the electrocardiogram signals and non-electrophysiologic signals. The rates may be used to discriminate between normal sinus rhythm and arrhythmia, and used to determining absence of an arrhythmia.

Abstract: The present invention outlines structures and methods for delivering a controllable amount of energy to a patient by automatically compensating for the load impedance detected by an implantable-cardioverter defibrillator (ICD). The invention employs high speed, switching power converter technology for the efficient generation of high energy, arbitrarywaveforms. Unlike a linear amplifier, switching power converters deliver high-energy waveforms with an efficiency that is independent of the size and amplitude of the desired waveform. An ICD that uses a switching power converter to deliver the desired energy to the patient stores the energy to be delivered in a storage capacitor. The converter then transforms this energy into an arbitrarily shaped output voltage-controlled or current-controlled waveform by switching the storage capacitor in and out of the output circuit at a high rate of speed. Preferably, the waveform comprises a ramp-type waveform.

Abstract: A cardiac rhythm management system measures a time interval between a first fiducial marker indicative of a ventricular depolarization (e.g., a Q-wave, an R-wave, etc.) and a second fiducial marker indicative of a subsequent mitral valve closure (MVC) occurring during the same cardiac cycle. Such time intervals are used for detecting atrioventricular (AV) dissociation. The AV dissociation may, in turn, be used for discriminating between a supraventricular tachyarrhythmia (SVT) and a ventricular tachyarrhythmia (VT) or for any other diagnostic or therapeutic purpose. The AV dissociation and/or SVT/VT discrimination information may be communicated from an implantable cardiac rhythm management device to an external interface and/or used to determine the nature of therapy delivered to the subject. In a further example, amplitudes indicative of the MVCs are also used for determining whether AV dissociation exists.

Abstract: A method of analysis of medical signals which uses wavelet transform analysis to decompose cardiac signals. Apparatus for carrying out the method, and cardiac apparatus adapted to employ the method are also described.

Abstract: Energy efficient methods and systems for using multi-dimensional activity sensors with implantable cardiac devices are provided. In certain embodiments the output of a passive activity sensor (used for rate responsive pacing) is used to trigger temporary use of a relatively high power multi-dimensional activity sensor. In other embodiments, the output of a relatively low power oxygen saturation sensor is used to trigger temporary use of a relatively high power multi-dimensional activity sensor. This description is not intended to be a complete description of, or limit the scope of, the invention.

Abstract: An improved apparatus and method for evaluating the need for, and performing as applicable, defibrillation. In one aspect, an improved defibrillation apparatus utilizing cardiographic impedance waveforms for determining cardiac output and accurately correlating this output to shockable or non-shockable cardiac conditions is disclosed. One exemplary embodiment uses electrodes having optimal spacing to enhance the accuracy of the impedance measurement. Another exemplary embodiment uses time-scale processing of the waveforms to identify fiducial points therein. Yet another embodiment uses advanced decision logic (such as fuzzy logic) to perform the aforementioned evaluation. The use of pacing spike detection and beat parsing based thereon is also disclosed.

Abstract: A system and method for detecting and discriminating atrial arrhythmias based on mechanical signals of cardiac wall motion and electrical signals of cardiac depolarizations. A mechanical event rate determined from sensed mechanical events is used to corroborate an electrical event rate determined from sensed EGM or ECG signals to classify the heart rhythm. If the event rates are not correlated, other parameterized data from the mechanical signal and electrical signal are evaluated to detect evidence of an arrhythmia. If electrical and mechanical event data do not corroborate a common arrhythmia condition, electrical and mechanical sensing parameters may be adjusted.

Abstract: A flat capacitor includes a case having a feedthrough hole, a capacitor stack located within the case, a coupling member having a base surface directly attached to the capacitor stack and having a portion extending through the feedthrough hole, the coupling member having a mounting hole, a feedthrough conductor having a portion mounted within the mounting hole, and a sealing member adjacent the feedthrough hole and the feedthrough conductor for sealing the feedthrough hole. Other aspects of the invention include various implantable medical devices, such as pacemakers, defibrillators, and cardioverters, incorporating one or more features of the exemplary feedthrough assembly.

Abstract: A method and apparatus for performing self-tests on defibrillation and pacing circuits including a patient isolation switch is disclosed. Tests are provided for the defibrillation and pacing circuitry as well as the isolation switch. For testing the defibrillation circuitry, the impedance drive circuits and preamplifier may be utilized such that the energy storage capacitor is not required to be charged and discharged during the test, thus conserving energy. For testing the pacing circuitry and the isolation switch, the defibrillation circuitry is utilized. For certain of the tests, the test stimulus is the output voltage on the energy storage capacitor, while for other tests the test stimulus may be the pace current as indicated by the voltage across the input to the preamplifier. Alternative tests may be performed depending on whether the impedance at the output of the defibrillator is determined to be an open circuit or a short circuit.

Abstract: An active implantable medical device of the defibrillation/cardioverter type able to detect a post-therapy sinusal tachycardia. This device includes circuits and logic able to detect ventricular and atrial activity; episodes of tachycardia and deliver a therapy for defibrillation and/or cardioversion, and/or antitachycardia stimulation. The detected tachycardia are classified, and there is selective control for the delivery of therapy according to the type of detected tachycardia classified. The device conducts further analysis of tachycardia after delivery of a shock therapy and is able to determine the presence of a post-therapy sinusal tachycardia, preferably by recognition of a stable ventricular rate, a 1:1 association of ventricular and atrial rates, a ventricular heart rate that is located in a range corresponding to a slow ventricular tachycardia. The device also is able to inhibit the delivery of a therapy in the presence of determined post-therapy sinusal tachycardia.

Abstract: An implantable cardiac device detects a patient therapy request originating from external to the implantable device. A shock therapy delay period is timed in response to the detection of the patient therapy request. Atrial shock therapy is provided to the patient after expiration of the shock therapy delay period (if the presence of an ongoing atrial arrhythmia is detected). The patient therapy request may be provided by a patient activator including a magnet for operating a reed switch in the implanted device to provide the request. A patient activator including an input and receiver/transmitter circuitry may be employed to request the immediate providing of atrial shock therapy, and/or to set the duration the shock therapy delay period. By allowing specific delays to therapy after a therapy request, a patient can prepare for the requested therapy and thereby mitigate therapy discomfort.

Abstract: An automatic external defibrillator including: a sensor for detecting when a rescuer is delivering a CPR chest compression to the patient; electrodes for application to the thorax of the patient for delivering a defibrillation shock to the patient and for detecting an ECG signal; defibrillation circuitry for delivering a defibrillation shock to the electrodes; and a processor and associated memory for executing software that controls operation of the defibrillator. The software provides: ECG analysis for analyzing the ECG signal to determine if the cardiac rhythm is shockable; CPR detection for analyzing the output of the sensor to determine when a CPR chest compression has been delivered, and integration of the ECG analysis and CPR detection so that the determination of whether the cardiac rhythm is shockable is based only on time periods of the ECG signal during which there has not been a CPR chest compression delivered.

Abstract: Apparatus for treating fibrillation of at least one chamber of a heart comprising a fibrillation detector for detecting a fibrillation, a defibrillator for defibrillating the chamber of the heart, wherein the defibrillator is connected to the fibrillation detector and is adapted to effect defibrillation subsequently to a time interval after detection of the fibrillation, a warning device which is connected to the fibrillation detector and which is adapted to delivery a warning signal when a fibrillation has been detected, and a control circuit having a control input actuable by a patient, wherein the control circuit is connected to the defibrillator and is adapted to delay the time of a defibrillation if the control circuit receives a corresponding signal by way of the control input, wherein the apparatus includes a condition detector which is adapted to detect a hemodynamic condition of the heart, and the control circuit is connected to the condition detector and is adapted to prevent a delay in the time of

Abstract: A sterile device immersed in a sterile buffer and a method for providing same. The sterile device may be a medical device such as a biosensor having a biomolecule as a sensing element such as, for example, a glucose oxidase enzyme. The buffer may be a bicarbonate solution. Both the device and the buffer may be packaged and stored over long term while maintaining sterilization. The sterilization method may comprise a combination of gaseous, liquid and light sterilization.

Abstract: An electrical method and apparatus for stimulating cardiac cells causing contraction to force hemodynamic output during fibrillation, hemodynamically compromising tachycardia, or asystole. Forcing fields are applied to the heart to give cardiac output on an emergency basis until the arrhythmia ceases or other intervention takes place. The device is used as a stand alone external or internal device, or as a backup to an ICD, atrial defibrillator, or an anti-tachycardia pacemaker. The method and apparatus maintain some cardiac output and not necessarily defibrillation.

Abstract: Cardiac systems and methods using ECG and blood information for arrhythmia detection and discrimination. Detection circuitry is configured to produce an ECG. An implantable blood sensor configured to produce a blood sensor signal is coupled to a processor. The processor is coupled to the detection and energy delivery circuitry, and used to evaluate and treat cardiac rhythms using both the cardiac electrophysiologic and blood sensor signals. The blood sensor is configured for subcutaneous non-intrathoracic placement and provided in or on the housing, on a lead coupled to the housing, and/or separate to the housing and coupled to the processor via hardwire or wireless link. The blood sensor may be configured for optical sensing, using a blood oxygen saturation sensor or pulse oximeter. A cardiac rhythm may be evaluated using the electrocardiogram signal and the blood sensor signal, and tachyarrhythmias may be treated after confirmation using the blood sense signal.

Abstract: A patient-controlled system for temporarily disabling an electrical cardioverting therapy in order to prepare the patient psychologically and physiologically for the pain associated with electrical cardioversion therapy. In an example embodiment, the system includes a capacitive circuit capable of charging and discharging in order to apply the electrical therapy. The implanted medical device automatically causes the capacitive circuit to charge and discharge at least once within a selected period. The system includes a patient activator device that communicates with the implanted device. A disabling circuit is also included within the implanted medical device that temporarily disables the electrical therapy application in response to the patient activator device. The system further includes an alerting arrangement that alerts the patient activator device in response to the disabling circuit.

Abstract: In one embodiment, a method is characterized by measuring a patient parameter associated with a human body; in response to the patient parameter, retrieving a maximum expected device parameter; and setting a limit on an energy source such that during defibrillation of the patient a defibrillation parameter associated with the maximum expected device parameter is within a defined tolerance. In another embodiment, a method is characterized by specifying at least one device parameter limit of a defibrillation unit; and in response to the at least one specified device parameter, determining a prediction confidence level at which the device parameter limit is exceeded for one or more values of a patient parameter.

Abstract: A method of reducing the likelihood of pulseless electrical activity (PEA) after defibrillation in a subject comprises administering to a subject afflicted with fibrillation a first treatment waveform, the first treatment waveform insufficient to defibrillate the heart; and then administering to the subject a second treatment waveform that defibrillates the heart and restores organized electrical activity in the heart. The first treatment waveform reduces the likelihood of onset of PEA following the second treatment waveform, as compared to that likelihood which would be present in the absence of the first treatment waveform.

Abstract: The presence of a cardiac pulse in a patient is determined by evaluating physiological signals in the patient. In one embodiment, a medical device evaluates optical characteristics of light transmitted into a patient to ascertain physiological signals, such as pulsatile changes in general blood volume proximate a light detector module. Using these features, the medical device determines whether a cardiac pulse is present in the patient. The medical device may also be configured to report whether the patient is in a VF, VT, asystole, or PEA condition, in addition to being in a pulseless condition, and prompt different therapies, such as chest compressions, rescue breathing, defibrillation, and PEA-specific electrotherapy, depending on the analysis of the physiological signals. Auto-capture of a cardiac pulse using pacing stimuli is further provided.

Abstract: A force sensor, for use in combination with an automated electronic defibrillator (AED), includes a first conductive layer. A second conductive layer is spaced apart from the first conductive layer such that no electrical communication occurs between the first and second conductive layers. An electrical communication device is provided for establishing electrical communication between the first and second conductive layers responsive to the application of a force to said electrical communication means.