Methods of diagnosis using pulse volume measurement

Abstract

The utility of pulse volume measurement is expanded to detection of many conditions which have previously not been detected or have been detected using more complicated techniques. Such conditions include blood loss, septic shock, cardiogenic shock, neonatal sepsis, patent ductus arteriosus, limb ischemia, intra-aortic balloon pump performance, peripheral vascular disease, congestive heart failure, the effectiveness of vasoactive medications, syncope, dehydration, pre-eclampsia, deep vein thrombosis, thermal injuries, vascular instability due to renal dialysis, compromising of circulation to the hand caused by radial artery harvesting, changes in cardiac output, and hypertension. According to the present invention, such diagnoses can be performed by taking one measurement, by taking measurements over time to detect a change or by taking measurements before and after application of a treatment or stimulus.

1 - 9 . (canceled)  
   
   
       10 . A method for detecting cardiogenic shock in a patient, the method comprising: 
 (a) taking a pulse volume measurement from the patient;    (b) determining, from the pulse volume measurement taken in step (a), whether the patient suffers from decreased cardiac output; and    (c) detecting the cardiogenic shock in accordance with the determination of step (b).    
   
   
       11 . The method of  claim 10 , wherein steps (a)-(c) are performed a plurality of times to determine effectiveness of treatment of the cardiogenic shock.  
   
   
       12 - 55 . (canceled)  
   
   
       56 . A method for diagnosing a physical condition in a patient, the method comprising: 
 (a) taking a pulse volume measurement from the patient;    (b) from the pulse volume measurement taken in step (a), calculating a quantity which is one of (i) a peak value of an instantaneous net inflow, (ii) an area under a pulse volume curve and (iii) a pulse volume×heart rate produce; and    (c) from the quantity calculated in step (b), diagnosing the physical condition.    
   
   
       57 . The method of  claim 56 , wherein steps (a) and (b) are performed a plurality of times to obtain different values of the quantity at different times, and wherein step (c) comprises comparing the different values of the quantity.  
   
   
       58 . The method of  claim 57 , further comprising applying a stimulus to the patient, and wherein the plurality of times comprise at least one time before the stimulus is applied and at least one time after the stimulus is applied.