Pneumatic compression device and methods for use in the medical field

Abstract

A multi-faceted pneumatic medical device including a pump unit. together with housing therefor, that is adapted for cyclical compression of the human foot using an expandable fluid-tight bladder formed integral within a wrap that can be securely fastened onto the foot.

I claim:  
     
         1 . A medical apparatus for affecting blood circulation comprising: 
 a foot wrap having an inflatable bladder for applying pressure to a patient's foot;    a pressure source for supplying pressure to said foot wrap;    a line in fluid communication with said pressure source; said line having an expansion reservoir therein for simulating the pressure in the bladder caused by the pressures losses in the apparatus;    a pressure sensing means including a pressure sensor connected to said line, downstream of said expansion reservoir, for sensing the amount to pressure supplied by said pressure source and converting the sensed amount into a signal; and    a control means in communication with said pressure sensing means to adjust the amount of pressure supplied by said pressure source.    
     
     
         2 . The apparatus of  claim 1  wherein said line further comprises at least one restrictor to restrict the flow of air pressure to said pressure sensor.  
     
     
         3 . The apparatus of  claim 1  wherein said signal includes an analog voltage signal, and said pressure sensing means further comprises an analog to digital conversion means to convert said voltage signal into a digital signal.  
     
     
         4 . The medical apparatus of  claim 1  wherein said control means comprises: 
 a microcontroller; and  
 a plurality of solenoid valves controlled by said micro-controller to adjust the amount of pressure supplied by said pressure source to said foot wrap.  
 
     
     
         5 . The apparatus of  claim 4  wherein said micro-controller is operable to read said digital signal from said pressure sensing means and to open and close said solenoid valves in response to the read signal.  
     
     
         6 . The apparatus of  claim 4  wherein said control means further comprises an error detection means for determining when pressure supplied by said pressure source is either to high or to low.  
     
     
         7 . The apparatus of  claim 4  wherein said control means further comprises: 
 an operator console having programmable keys to enter user settings; and memory means for storing said user settings to be processed by said micro-controller.  
 
     
     
         8 . The apparatus of  claim 7  wherein said operator console further comprises a liquid crystal display.  
     
     
         9 . The apparatus of  claim 7  wherein said memory means comprises an electronically erasable programmable read only memory.  
     
     
         10 . A medical apparatus for cyclically applying pressure to a foot, comprising: 
 a flexible fabric foot wrap formed from two sheets and having an inflatable bladder therein,    a connector opening into the inflatable bladder and suitable for connection to a source of pressurized fluid;    said foot wrap having a first tab formed from at least one of said two sheets for releasably securing the device to a human foot about the arch, the first tab having a releasable connector at its distal end;    said foot wrap having a second tab formed from at least one of said two sheets for releasably securing the device to a human foot about the heel, the second tab being generally perpendicular to the first tab, the second tab having a releasable connector at its distal end;    said foot wrap having an exterior surface portion on one of said sheets compatible with said releasable connectors so that a connection may be formed when said connectors are pressed against said surface;    a source for supplying pressurized fluid to said inflatable bladder;    pressure sensing means for measuring the amount of pressure supplied by said source; and    a control means in communication with said pressure sensing means to adjust the amount of pressure supplied by said source.    
     
     
         11 . The medical apparatus of  claim 10 , further comprising: 
 a housing for releasably mounting said source on the foot board of a standard hospital bed, said housing comprising a pair of opposite, retractable mounting hooks having sloped surfaces for biasing the source toward said foot board and having knobs at the distal ends thereof for helping retain the hooks on the foot board; and    said hooks further having a horizontal bearing surface for engaging the top of foot boards having smaller widths.    
     
     
         12 . An inflatable device for pneumatic compression of the foot, comprising: 
 an inflatable chamber for wrapping around the foot and compressing the foot when inflated;    a strap formed integral with said first member for wrapping around the lower portion of a leg and securing the first member in place; and    said strap comprising means for cushioning a skin-engaging surface of said strap for minimizing localized pressure concentrations related to said surface.    
     
     
         13 . A medical apparatus for affecting blood circulation comprising: 
 a foot wrap having an inflatable bladder for applying pressure to a patient's foot;    a pressure source for supplying pressurized gas to said foot wrap;    a line in fluid communication with said pressure source;    a control means having a valve means for controlling the supply to supply of said pressurized gas;    a pressure sensing means including a pressure sensor connected to said line for sensing the amount of pressurized gas being supplied by said pressure source upon opening of the valve means and converting the sensed amount into a signal for controlling the valve means; and    said control means being operatively connected with said pressure sensing means turn off the valve means to adjust the amount of pressurized gas being supplied by said pressure source.    
     
     
         14 . A method for affecting blood circulation comprising: 
 applying a foot wrap having an inflatable bladder for applying pressure to a patient's foot;    supplying pressurized gas from a pressure source to said foot wrap;    sensing the amount of pressurized gas being supplied by said pressure source in an expansion reservoir for simulating the pressure in the bladder caused by pressures losses and converting the sensed amount into a signal for controlling the amount of pressurized gas being supplied by said pressure source.    
     
     
         15 . A method for affecting blood circulation comprising: applying a foot wrap having an inflatable bladder for applying pressure to a patient's foot; 
 supplying pressurized gas from a pressure source to said foot wrap;    controlling the supply of pressurized gas with a valve means;    sensing the amount of pressurized gas being supplied by said pressure source upon opening of the valve means and converting the sensed amount into a signal for controlling the valve means; and    turning off the valve means to adjust the amount of pressurized gas being supplied by said pressure source.