Fluid therapy method

Abstract

A fluid therapy method for an ADHF patient includes setting a urine output rate desired threshold, setting one or more desired negative net gain rates, and optionally setting a total fluid loss goal. The urine output of the patient is monitored and fluid is automatically administered to the patient at increasing rates to equal to or approximately match the patient's increasing urine output rates until the patient's urine output rate reaches the set urine output rate desired threshold. Thereafter, fluid is administered to the patient at rates to achieve the set desired negative net gain rate until the fluid loss goal is reached. Thereafter, until the end of therapy, fluid is administered to the patient at rates equal to or approximately equal to the monitored urine output rates.

What is claimed is: 
     
         1 . A fluid therapy method comprising:
 setting a urine output rate desired threshold;   setting one or more desired negative net gain rates;   monitoring the urine output of a patient;   automatically administering a fluid to the patient at increasing rates to equal to or approximately match the patient's increasing urine output rates until urine output rate reaches the set urine output rate desired threshold;   automatically thereafter administering the fluid to the patient at rates to achieve the set desired negative net gain rate.   
     
     
         2 . The method of  claim 1  further including setting a desired total fluid loss goal and wherein fluid is automatically administered to the patient at said rates to achieve the set desired negative net gain until said set desired fluid loss goal is reached and thereafter, until the end of therapy, automatically administering the fluid to the patient at rates equal to or approximately equal to the monitored urine output rates. 
     
     
         3 . The method of  claim 1  in which monitoring the urine output rates includes collecting urine in a urine collection bag and weighing the urine collection bag as a function of time. 
     
     
         4 . The method of  claim 1  in which administering fluid to the patient includes pumping fluid from a fluid bag into the patient using a fluid pump. 
     
     
         5 . The method of  claim 4  including monitoring the operation of the fluid pump over time and/or weighing the fluid bag as a function of time to determine the rate of fluid infusion. 
     
     
         6 . The method of  claim 1  in which the fluid is saline or an osmotic solute. 
     
     
         7 . The method of  claim 1  further including administering to the patient a bolus of fluid during therapy. 
     
     
         8 . The method of  claim 1  further including administering to the patient a diuretic during the therapy. 
     
     
         9 . The method of  claim 8  in which the diuretic is administered at the start of therapy. 
     
     
         10 . The method of  claim 8  in which the diuretic is administered automatically. 
     
     
         11 . The method of  claim 8  in which the diuretic is administered during the therapy when fluid is administered to the patient at rates less than the monitored urine output rates according to the set desired negative net gain rate. 
     
     
         12 . The method of  claim 1  in which the urine output rate desired threshold and the desired negative net gain rate are set via stored default values. 
     
     
         13 . The method of  claim 1  in which the desired negative net gain changes during therapy as a function of time. 
     
     
         14 . The method of  claim 1  in which the user is automatically informed when the urine rate desired threshold is met. 
     
     
         15 . The method of  claim 1  in which the user is automatically informed when the total fluid loss goal is met. 
     
     
         16 . The method of  claim 1  in which the infusion fluid is hypertonic saline. 
     
     
         17 . The method of  claim 1  in which the hypertonic saline infusion is adjusted based on a urine or serum sodium sensor. 
     
     
         18 . A fluid therapy method comprising:
 setting one or more desired negative net gain rates;   setting a desired fluid loss goal;   monitoring the urine output of a patient;   administering a diuretic to the patient;   automatically administering a fluid to the patient to achieve a set desired negative net gain rate until the desired fluid loss goal is reached; and   thereafter, until the end of therapy, automatically administering fluid to the patient at rates equal to or approximately equal to monitored urine output rates.   
     
     
         19 . A method comprising:
 monitoring the urine output of a patient;   automatically administering a fluid to the patient at rates equal to or approximately equal to monitored urine output rates until the urine output rate reaches a desired threshold; and   automatically thereafter administering the fluid to the patient to achieve a set desired negative net gain rate to take off fluid.   
     
     
         20 . The method of  claim 19  further including, after a total fluid loss goal is reached, until the end of therapy, automatically administering fluid to the patient at rates equal to or approximately equal to monitored urine output rates. 
     
     
         21 . A fluid therapy system comprising:
 a console including an input for setting a urine output rate desired threshold and for setting one or more desired negative net gain rates;   a urine output measuring subsystem;   a fluid administration subsystem; and   a controller subsystem responsive to the urine output measuring subsystem and configured to monitor the urine output rates of a patient and to control the fluid administration subsystem to:
 automatically administer fluid to the patient at rates equal to or approximately equal to the monitored urine output rate until the urine output rates reaches the set desired threshold, and 
 automatically thereafter administer fluid to the patient at rates to achieve the set desired negative net gain rate. 
   
     
     
         22 . The system of  claim 21  in which the console input allows setting of a total fluid loss goal and the controller subsystem is configured to administer fluid to the patient at rates equal to or approximately equal to the monitored urine output rates after a set total fluid loss goal is reached until the end of therapy. 
     
     
         23 . The system of  claim 21  in which the urine output measuring subsystem includes means for weighing a urine collection bag. 
     
     
         24 . The system of  claim 21  in which the fluid administration subsystem includes a fluid pump and means for weighing a fluid bag connected to the fluid pump. 
     
     
         25 . The system of  claim 21  in which the fluid administration system is configured to administer both hydrating fluid and a diuretic. 
     
     
         26 . The system of  claim 21  in which the controller subsystem is configured to control the fluid administration system to automatically administer a diuretic at the start of therapy. 
     
     
         27 . The system of  claim 21  in which the controller subsystem is configured to inform the user that the target urine output threshold has been met. 
     
     
         28 . The system of  claim 21  in which the controller subsystem is configured to inform the user that the target urine output threshold has not been met after an expected time interval. 
     
     
         29 . The system of  claim 21  in which the controller subsystem is configured to inform the user that the total fluid loss goal has been met 
     
     
         30 . A method of treating a patient with excess fluid, the method comprising:
 setting a urine output rate desired threshold;   setting a negative net fluid gain rate;   setting a desired total fluid loss goal;   administering a diuretic to the patient to induce urine output;   for a first therapy period after beginning diuretic administration, driving the urine output rate of the patient to a higher level matching or exceeding the set urine output rate desired threshold by automatically infusing fluid into the patient at rates which match or closely match the patient's urine output rates resulting in little or no total fluid loss; and   for a second therapy period after the set urine output rate desired threshold is reached, inducing fluid loss at said set negative net fluid gain rate by automatically decreasing the amount of fluid infused and infusing fluid at rates which are less than but a function of the patient's urine output rates until said set desired total fluid loss goal is reached.   
     
     
         31 . The method of  claim 30  further including a third therapy period wherein fluid is automatically infused at rates equal to or approximately equal to the patient's urine output rates after the desired total fluid loss goal is reached and until the end of therapy resulting in little or no total fluid loss during the third therapy period to prevent patient dehydration. 
     
     
         32 . The method of  claim 30  further including administering a diuretic to the patient during the second therapy period. 
     
     
         33 . The method of  claim 32  wherein the diuretic is administered automatically. 
     
     
         34 . The method of  claim 30  in which monitoring the urine output rates includes collecting urine in a urine collection bag and weighing the urine collection bag as a function of time. 
     
     
         35 . The method of  claim 30  in which administering fluid to the patient includes pumping fluid from a fluid bag into the patient using a fluid pump and automatically controlling the operation of the fluid pump. 
     
     
         36 . The method of  claim 35  including monitoring the operation of the fluid pump over time and/or weighing the fluid bag as a function of time to determine the rate of fluid infusion. 
     
     
         37 . The method of  claim 30  in which the infusion fluid is saline or an osmotic solute. 
     
     
         38 . The method of  claim 30  further including automatically administering to the patient a bolus of fluid during therapy. 
     
     
         39 . The method of  claim 30  further including automatically administering to the patient the diuretic. 
     
     
         40 . The method of  claim 30  in which the urine output rate desired threshold, the desired negative net gain rate, and the desired total fluid loss goal are set via stored default values. 
     
     
         41 . A fluid therapy method comprising:
 administering a diuretic to the patient to induce urine output;   automatically monitoring the patient's urine output rates;   for a first therapy period after administration of the diuretic, driving the urine output rate of the patient to a higher level by automatically controlling an infusion pump to infuse fluid into the patient at rates which match or closely match the monitored patient's urine output rates until a set urine output rate threshold is reached resulting in little or no total fluid loss during the first therapy period; and   for a second therapy period after the set urine output rate threshold is reached, inducing fluid loss at a set negative net fluid gain rate by automatically controlling the infusion pump to decrease the amount of fluid infused and controlling the infusion pump to infuse fluid at rates which are less than but a function of the patient's urine output rates until a set desired total fluid loss goal is reached during the second therapy period.   
     
     
         42 . The method of  claim 41  further including a third therapy period wherein the infusion pump is controlled to infuse fluid at rates equal to or approximately equal to the patient's urine output rates after the set desired total fluid loss goal is reached and until the end of therapy resulting in little or no total fluid loss during the third therapy period to prevent patient hydration. 
     
     
         43 . A fluid therapy system comprising:
 a console including an input for setting a urine output rate desired threshold and for setting a desired negative net fluid gain rate;   a urine output measuring subsystem;   a fluid administration subsystem; and   a controller subsystem, responsive to the urine output measuring system and configured to monitor the urine output rates of a patient and to control the fluid administration subsystem to automatically:   drive the urine output rate of the patient to a high level matching or exceeding the set urine output rate desired threshold by controlling the fluid administration subsystem to infuse fluid into the patient at rates that match or closely match the patient's urine output rates as measured by the urine output measuring subsystem resulting in little or no total fluid loss during a first therapy period; and   after the set urine output rate desired threshold is reached, inducing fluid loss at said set desired negative net fluid gain rate by controlling the fluid administration subsystem to infuse fluid at rates which are less than but a function of the patient's urine output rates as measured by the urine output measuring subsystem until said set desired total fluid loss goal it reached.   
     
     
         44 . The system of  claim 43  in which the controller subsystem is further configured to automatically control the fluid administration subsystem to infuse fluid at rates equal to or approximately equal to the patient's urine output rates as measured by the urine output measuring subsystem after the desired total fluid loss goal is reached and until the end of therapy resulting in little or no total fluid loss during a third therapy period to prevent patient dehydration. 
     
     
         45 . The system of  claim 43  further including a subsystem for automatically administering a diuretic to the patient before the first therapy period and, optionally, during the second therapy period.