Wrist Mounted CPR Chest Compression Monitor

Abstract

A chest compression monitor for measuring the depth of chest compressions achieved during CPR. A displacement detector produces a displacement indicative signal indicative of the displacement of the CPR recipient's chest toward the recipient's spine. A signaling mechanism provides chest compression indication signals directing a chest compression force being applied to the chest and a frequency of such compressions.

1 . A system for monitoring the compression of the chest of a patient during CPR, said system comprising:
 a chest compression monitor comprising an accelerometer adapted to sense upward and downward acceleration of the chest compression monitor, said compression monitor further adapted to output an acceleration signal indicative of the upward and downward acceleration of the chest, said compression monitor housed in a module adapted to be held in fixed relationship to a CPR provider's wrist while the CPR provider is manually compressing the patient's chest.   
     
     
         2 . The system of  claim 1  further comprising a releasable fixing mechanism for attaching the chest compression monitor to a CPR provider's wrist. 
     
     
         3 . The system of  claim 1 , further comprising a computer programmed to process the acceleration signal to determine the depth of chest compression and produce a compression signal indicative of the depth of compression of the patient's chest. 
     
     
         4 . The system of  claim 1 , wherein the computer is further programmed to provide an audible signal modulated to indicate when the proper chest displacement is achieved by the CPR provider. 
     
     
         5 . The system of  claim 1 , wherein the computer is further programmed to determining the start of a compression without reference to a signal derived from a source external to the module, and thereafter calculate downward displacement of the chest using the acceleration signal; said computer further programmed to output a compression signal. 
     
     
         6 . The system of  claim 1  wherein:
 the computer is further programmed to determine the start of a compression based on the acceleration signal, a zero-point of acceleration and changes in the direction of velocity of the module. 
 
     
     
         7 . The system of  claim 1  wherein:
 the computer is further programmed to determine the end of a compression based on the acceleration signal, a zero-point of acceleration and changes in the direction of velocity of the module. 
 
     
     
         8 . A method for monitoring the compression of the chest of a patient during CPR, said system comprising:
 providing a chest compression monitor comprising an accelerometer adapted to sense upward and downward acceleration of the chest compression monitor, said compression monitor further adapted to output an acceleration signal indicative of the upward and downward acceleration of the chest, said compression monitor housed in a module fixed to a releasable fixing mechanism for fixing the module to the CPR provider's wrist;   attaching the chest compression monitor to a CPR provider's wrist with the releasable fixing mechanism;   measuring an acceleration signal provided by the accelerometer while the CPR provider is compressing the chest of the patient;   providing a computer operable to process the acceleration signal to determine the depth of chest compression and produce a compression signal indicative of the depth of compression of the patient's chest, and processing the acceleration signal to determine the depth of chest compression and produce a compression signal indicative of the depth of compression of the patient's chest.   
     
     
         9 . The method of  claim 8  further comprising the step of operating the computer to provide an audible signal modulated to indicate when the proper chest displacement is achieved by the CPR provider. 
     
     
         10 . The method of  claim 8  further comprising the step of operating the computer to determine the start of a compression without reference to a signal derived from a source external to the module, and thereafter calculate downward displacement of the chest using the acceleration signal. 
     
     
         11 . The method of  claim 8  further comprising the step of operating the computer to determine the start of a compression based on the acceleration signal, a zero-point of acceleration and changes in the direction of velocity of the module. 
     
     
         12 . The method of  claim 8  further comprising the step of operating the computer to determine the end of a compression based on the acceleration signal, a zero-point of acceleration and changes in the direction of velocity of the module.