Automatic defibrillator module for integration with standard patient monitoring equipment

This application is a continuation of copending application Ser. No. 11/180,396 filed Jul. 13, 2005, which was a division of U.S. patent application Ser. No. 09/523,912 filed Mar. 9, 2000, now U.S. Pat. No. 7,006,865. The entire disclosures of these related applications are expressly incorporated herein by reference.

A. Field of Invention

This invention pertains to an external defibrillator module arranged and constructed to provide anti-tachyarrhythmia therapy to a patient. In particular, an automatic external defibrillator module is described which has several operational modes including a fully automatic mode in which shocks are delivered without any manual intervention, an advisory mode, a manual mode, and a pacer mode. Moreover, the invention pertains to a defibrillator module which is arranged and constructed for integration with patient monitoring equipment for sharing certain functions and information using a standard or customized protocol.

B. Description of the Prior Art

Defibrillators are devices which apply electric therapy to cardiac patients having an abnormally high heart rhythm or fibrillation. Two kinds of defibrillators are presently available: internal defibrillators which are implanted subcutaneously in a patient together with leads extending through the veins into the cardiac chambers, and external defibrillators which are attached (usually temporarily) to the patient. External defibrillators are used in most instances in case of an emergency, for example, when a patient has either suffered cardiac arrest or when a cardiac arrest is imminent. Typically, therefore external defibrillators are manual devices which must be triggered by a physician or other trained personnel. Internal or implantable defibrillators (and cardioverters) are implanted as a permanent solution for patients having specific well-defined cardiac deficiencies which cannot be treated successfully by other means. They generally operate in an automatic mode.

Commonly-owned U.S. Pat. No. 5,474,574 discloses an external defibrillator. Commonly-owned U.S. Pat. Nos. 4,576,170 and 5,474,574, incorporated herein by reference discloses external defibrillators.

Several patient monitoring systems are presently available in modular form which allow a clinician or other health professional to monitor and display various physiological parameters of a patient. Typically these units include several subassembly modules which cooperate to acquire data from the patient, to store the data electronically and to display information about a patient\'s physiological status. The systems may also be adapted to generate audible and/or visual alarms when certain criteria are met. Some systems may also be integrated into a communications network covering, for example, a part or even a whole hospital and on which data is exchanged for various purposes. Monitoring systems of this kind are available from GE Marquette Medical Systems of Milwaukee, Wis.; Agilent Technologies of Andover, Mass.; Spacelabs Medical of Redmond, Wash., and many other companies. However, typically these systems are passive in that their main purpose is to monitor, collect information and generate alarms. These systems cannot provide therapy.

An objective of the present invention is to provide an automatic defibrillator module which is capable of detecting a current cardiac condition of a patient and of providing appropriate therapy to the patient, when needed.

A further objective is to provide an automatic defibrillator module which can be interfaced with a existing or future patient monitoring systems in a manner which allows the system and the module to share information and other common functions.

Yet another objective is to provide an external defibrillator module with several modes of operation, including an automatic mode in which shocks are applied on demand in accordance with preprogrammed shock parameters and without any prompting from an attendant, an advisory mode in which an attendant is alerted to a shockable rhythm however the application of shocks must be initiated by the attendant, a manual mode in which the attendant determines how and when shocks should be applied and the preprogrammed shock parameters are ignored, and a pacer mode for pacing certain cardiac events.

Other objectives and advantages of the invention will become apparent from the following description of the invention.

• • Briefly, a composite monitoring system constructed in accordance with this invention comprises a patient monitor including a sensor arranged to sense a physiological characteristic of a patient and a signal processor coupled to said sensor and adapted to process the signal from said sensor and an output member; and a defibrillator module adapted to be selectively coupled to said patient monitor, said defibrillator module including a pulse generator responsive to commands to generate therapeutic pulses for the patient, and a data generator arranged to generate indication signals indicative of an operation of said defibrillator module; wherein said patient monitor and said defibrillator module cooperating when coupled to transfer said indication signal to said output member whereby said output member generates output signals corresponding to one of said patient characteristic and said indication signals. The patient monitor may include a display that can be used to show signals or data associated with either the physiological characteristics being monitored or information pertaining to the operation of the defibrillator module. The patient monitor could also include audible and visual alarms, a printer, and a connection to a network through which data could be sent to a remote location. All these components could be shared between the patient monitor and the defibrillator module. Data between the defibrillator module and the patient monitor is exchanged using either a protocol standardized for the monitor or by using a customized protocol.