Method of determining lung condition indicators

Abstract

A method and a microprocessor controlled device for use in medical evaluation of the pulmonary system. The method and device incorporate two different non invasive evaluative techniques. Passive auscultation provides indicators of lung condition. Active auscultation, a different evaluative technique, provides information or indications generally not available or provided from passive auscultation. Combining the information from both techniques greatly improves the ability to provide effective medical treatment.

1 . A method of determining the condition of a patient's lungs, comprising: 
 making an active measurement of the patient's lungs by injecting a signal comprising audible frequencies through the patient's lungs;    making a passive measurement of the patient's lungs by monitoring the breath sounds of the patient during a breathing cycle;    combining results from the active measurement with the passive measurement.    
   
   
       2 . The method of  claim 1  wherein making an active measurement further comprises determining one or more variables from the measurement.  
   
   
       3 . The method of  claim 2  wherein one variable is the velocity of the injected signal.  
   
   
       4 . The method of  claim 3  wherein the velocity is determined over a range of frequencies.  
   
   
       5 . The method of  claim 4  wherein the range of frequencies comprises a range from about 20 HZ to about 50 kHZ.  
   
   
       6 . The method of  claim 2  wherein one variable is the phase of the injected signal.  
   
   
       7 . The method of  claim 2  wherein one variable is the dispersion of frequencies over a range of frequencies.  
   
   
       8 . The method of  claim 1  further comprising ceasing to make an active measurement while making a passive measurement.  
   
   
       9 . The method of  claim 1  further comprising calculating a ratio of an amplitude of the signal at a first frequency versus the amplitude of the signal at a second frequency.  
   
   
       10 . The method of  claim 1  further comprising calculating a ratio of a velocity of the signal at a first frequency versus a velocity of the signal at a second frequency.  
   
   
       11 . The method of  claim 1  further comprising calculating a ratio of an attenuation of the signal at a first frequency versus the attenuation of the signal at a second frequency.  
   
   
       12 . A method of determining the condition of a patient's lungs, comprising: 
 injecting a signal including audible frequencies through the patient's lungs;    recording the injected signal and processing the signal to determine a first set of criteria indicative of a condition of the lungs;    monitoring naturally occurring breath sounds of the patient's lungs;    processing the breath sounds of the patient's lungs to determine a second set of criteria indicative of a condition of the lungs; and    narrowing the number of criteria indicative of a condition of the lungs by comparing the first set of criteria from the injected signal with the second set of criteria from the naturally occurring breath sounds.    
   
   
       13 . The method of  claim 12  wherein recording the injected signal comprises receiving the injected signal with a plurality of transducers.  
   
   
       14 . The method of  claim 12  wherein monitoring the naturally occurring breath sounds comprises monitoring a plurality of transducers.  
   
   
       15 . The method of  claim 12  wherein recording the injected signal does not occur at the same time as monitoring the naturally occurring breath sounds.  
   
   
       16 . A device for evaluating the condition of a lung, comprising: 
 an emitting transducer that injects a signal having audible frequencies through the lung;    one or more receiving transducers that receive the injected signal; and    a processing unit that monitors the injected signal, and determines a first set of indicators of the condition of the lung from the injected signal, and that    monitors naturally occurring breath sounds of the lung and determines a second set of indicators of the condition of the lung, and that    compares the first and second set of indicators and provides a third set of indicators comprising the overlap of a portion of the first and second indicators respectively, thereby providing a set of indicators of lung condition based upon both the injected signal and the naturally occurring breath sounds.    
   
   
       17 . A device for evaluating the condition of a lung, comprising: 
 an emitting transducer that injects a signal having audible frequencies through the lung;    one or more receiving transducers that receive the injected signal, the one or more receiving transducers also monitoring natural breath sounds of the lung; and    means for producing an indication of the condition of the lung based upon both the natural breath sounds and upon the injected signal.    
   
   
       18 . A method of determining the condition of a patient's lungs, comprising: 
 injecting a signal comprising audible frequencies into the patient's lungs;    determining the speed of sound of the injected audible signal through the patient's lung tissue;    calculating a property of the lung tissue;    correlating the property with a first indication of the condition of the patient's lungs;    monitoring an amplitude of a breath sound of the patient's lungs as the patient inhales and exhales;    correlating the monitored breath sound amplitude with a second indication of the condition of the patient's lung; and    combining the first and second indications to narrow the possibilities of the condition of the patients lungs.    
   
   
       19 . The method of  claim 18  where the condition comprises one or more of emphysema, bronchitis, chronic obstructive pulmonary disorder, or asthma.