Blood pressure monitor

Abstract

The present invention relates to an apparatus and method for facilitating blood pressure measurement. An additional fluid reservoir is arranged to be connected in fluid communication with the blood pressure cuff. The fluid reservoir provides an additional, compliant volume to the fluid volume of the cuff, facilitating blood pressure measurement, particularly for small volume cuffs.

1 . An apparatus for facilitating blood pressure measurement, including a fluid reservoir arranged to be connected in fluid communication with a blood pressure cuff, the fluid reservoir being arranged to provide an additional fluid volume to the fluid volume of the cuff during measurement of blood pressure of a patient. 
     
     
         2 . An apparatus in accordance with  claim 1 , wherein the fluid reservoir is arranged to change in volume when a change in pressure is applied. 
     
     
         3 . An apparatus in accordance with  claim 2 , a fluid reservoir being arranged to add little or no pressure back into the system when it changes in volume. 
     
     
         4 . An apparatus in accordance with  claim 1 ,  2  or  3 , wherein the fluid reservoir has a compliance. 
     
     
         5 . An apparatus in accordance with  claim 4 , wherein the compliance is arranged such that oscillations of pressure from the blood pressure cuff are not significantly damped by the fluid reservoir. 
     
     
         6 . An apparatus in accordance with  claim 4  or  claim 5 , wherein the compliance is arranged such that the pressure on the fluid reservoir during any blood pressure measurement does not exceed the fluid reservoir's Critical Opening Pressure. 
     
     
         7 . An apparatus in accordance with  claim 4 ,  5  or  6 , wherein the fluid reservoir includes a fluid container having at least one expandable wall providing compliance. 
     
     
         8 . An apparatus in accordance with  claim 7 , wherein the fluid container is of flexible plastic material. 
     
     
         9 . A system for measuring blood pressure, including an apparatus in accordance with any one of the preceding claims and a blood pressure cuff, the fluid reservoir being arranged to be connected in fluid communication with the blood pressure cuff. 
     
     
         10 . An automated system for measuring blood pressure, including a controller for controlling the provision of fluid under pressure to a blood pressure cuff, a display for providing a reading of blood pressure value, and an apparatus in accordance with any one of  claims 1  to  6 , the fluid reservoir being arranged to be connected in fluid communication with the blood pressure cuff. 
     
     
         11 . A method of measuring blood pressure using a blood pressure cuff, including the step of providing an additional fluid volume in fluid connection with the blood pressure cuff. 
     
     
         12 . A method in accordance with  claim 11 , wherein the additional fluid volume is arranged to change the effective volume of the blood pressure cuff when a change of pressure is applied. 
     
     
         13 . A method in accordance with  claim 12 , wherein when the additional fluid volume changes the effective volume of the cuff, it is arranged to add little or no pressure back into the system. 
     
     
         14 . A method in accordance with  claim 11 ,  12  or  13 , wherein the additional fluid volume has a compliance. 
     
     
         15 . A method in accordance with  claim 14 , wherein the compliance is sufficient such that oscillations of pressure from the blood pressure cuff are not significantly damped. 
     
     
         16 . A method in accordance with  claim 14  or  claim 15 , wherein the compliance is such that the pressure on the fluid reservoir during any blood pressure measurement will not exceed the fluid reservoir's Critical Opening Pressure. 
     
     
         17 . An apparatus for facilitating pressure measurement, including a fluid reservoir arranged to be connected in fluid communication with a pressure measuring device, the fluid reservoir being arranged to provide an additional fluid volume to a fluid volume of the pressure measurement device during measurement of pressure. 
     
     
         18 . A method of making a pressure measurement, including the step of providing an additional fluid volume in fluid connection with a pressure measuring device having a fluid volume for measurement of pressure.