PATIENT PRE-BUN ESTIMATE BASED ON SORBENT RECHARGER EFFLUENT DATA
The invention relates to devices, systems, and methods for estimating a patient BUN level prior to a dialysis session based on data received when introducing an ammonium removal solution through a zirconium phosphate sorbent module. The systems and methods can introduce an ammonia removal solution and determine an ammonia content of the ammonium removal solution effluent to estimate the patient pre-dialysis BUN level.
1 . A method, comprising:
introducing one or more ammonium removal solutions into a zirconium phosphate sorbent module ( 102 );
determining a total ammonia content in an ammonium removal solution effluent of the zirconium phosphate sorbent module using an ammonia sensor ( 108 ); and
estimating a patient pre-dialysis BUN level based on the total ammonia content in the ammonium removal solution effluent.
2 . The method of claim 1 , wherein the ammonia sensor is in an effluent line ( 109 ) fluidly connectable to an outlet ( 104 ) of the zirconium phosphate sorbent module.
3 . The method of claim 1 , further comprising the step of introducing the ammonium removal solution effluent into a reservoir ( 107 ), and wherein the step of determining the total ammonia content in the ammonium removal solution effluent comprises determining the total ammonia content in the reservoir.
4 . The method of any of claims 1 - 3 , wherein the step of estimating the patient pre-dialysis BUN level comprises determining a total ammonia content of the ammonium removal solution effluent to determine a volume averaged total ammonia content of the ammonium removal solution effluent.
5 . The method of claim 4 , wherein determining the total ammonia content of the ammonium removal solution effluent comprises integrating the total ammonia content in the ammonium removal solution effluent.
6 . The method of any of claims 1 - 5 , further comprising the step of determining an amount of ammonia removed by the zirconium phosphate sorbent module during a dialysis session.
7 . The method of claim 6 , wherein the step of estimating the patient pre-dialysis BUN level uses an equation:
C
Burea
,
pre
=
(
C
_
NH
4
*
V
eff
)
/
2
V
prp
-
V
post
(
1
-
URR
)
,
wherein C Burea, pre is a patient pre-dialysis urea level, C NH4 is a volume averaged total ammonia content in the ammonium removal solution effluent; V eff is a volume of ammonia removal solution introduced through the zirconium phosphate sorbent module, V pre is a patient water volume prior to a dialysis session, V post is a patient water volume after the dialysis session, and URR is a urea reduction ratio for the dialysis session.
8 . The method of any of claims 1 - 7 , wherein the method uses a sorbent recharger, wherein the one or more ammonium removal solutions comprise one or more recharge solutions; and wherein the step of introducing the one or more recharge solutions through the zirconium phosphate sorbent module comprises first introducing water through the zirconium phosphate sorbent module and then introducing a brine solution through the zirconium phosphate sorbent module.
9 . The method of claim 8 , wherein the step of determining the total ammonia content in the ammonium removal solution effluent comprises determining the total ammonia content while introducing the water through the zirconium phosphate sorbent module and determining the total ammonia content while introducing the brine solution through the zirconium phosphate sorbent module.
10 . The method of claim 8 , wherein the step of determining the total ammonia content in the ammonium removal solution effluent comprises determining the total ammonia content while introducing the brine solution through the zirconium phosphate sorbent module.
11 . The method of any of claims 1 - 10 , wherein the step of determining the total ammonia content in the ammonium removal solution effluent comprises continuously determining the total ammonia content in the ammonium removal solution effluent.
12 . The method of claim 1 , wherein the step of determining the total ammonia content in the ammonium removal solution effluent comprises determining the total ammonia content in the ammonium removal solution effluent at preset intervals.
13 . The method of claim 1 , wherein a processor is programmed to estimate the patient pre-dialysis BUN level based on the total ammonia content in the ammonium removal solution effluent.
14 . A system, comprising:
an ammonium removal flow path ( 101 ) comprising: at least one ammonium removal solution source ( 105 ); the ammonium removal solution source fluidly connectable to a zirconium phosphate sorbent module ( 102 ) inlet ( 103 ); a pump ( 106 ); and an effluent line ( 109 ) fluidly connectable to a zirconium phosphate module outlet ( 104 );
at least one ammonia sensor ( 108 ); and
a processor in communication with the at least one ammonia sensor, the processor estimating a patient pre-dialysis BUN level based on a total ammonia content in an ammonium removal solution effluent of the zirconium phosphate sorbent module.
15 . The system of claim 14 , wherein the system comprises a sorbent recharger; and wherein the at least one ammonium removal solution source comprises at least a water source ( 306 ) and a brine source ( 305 ).
16 . The system of claim 14 or 15 , the processor further determining an amount of ammonia removed by the zirconium phosphate sorbent module.
17 . The system of any of claims 14 - 16 , wherein the processor estimates the patient pre-dialysis BUN level using an equation:
C
Burea
,
pre
=
(
C
_
NH
4
*
V
eff
)
/
2
V
prp
-
V
post
(
1
-
URR
)
,
wherein C Burea, pre is the patient pre-dialysis urea level, C NH4 is a volume averaged total ammonia content in the ammonium removal solution effluent; V eff is a volume of ammonium removal solutions introduced through the zirconium phosphate sorbent module, V pre is a patient water volume prior to a dialysis session, V post is a patient water volume after the dialysis session, and URR is a urea reduction ratio for the dialysis session.
18 . The system of claim 17 , wherein the processor is programmed to determine the urea reduction ratio using an equation: URR=1-e −kt/V wherein k is a dialyzer clearance, t is a length of time of a dialysis session, and visa patient water volume.
19 . The system of claim 14 , wherein the processor is programmed to receive the total ammonia content of the ammonium removal solution effluent from the at least one ammonia sensor continuously during the method.
20 . The system of claim 14 , wherein the processor is programmed to receive the total ammonia content of the ammonium removal solution effluent from the at least one ammonia sensor at preset intervals.
21 . The system of claim 15 , wherein the processor controls the pump to first introduce water from the water source through the zirconium phosphate sorbent module, and then introduce brine from the brine source through the zirconium phosphate sorbent module.
22 . The system of claim 21 , wherein the processor is programmed to receive the total ammonia content of the ammonium removal solution effluent while water is introduced through the zirconium phosphate sorbent module and while brine is introduced through the zirconium phosphate sorbent module.
23 . The system of claim 21 , wherein the processor is programmed to receive the total ammonia content of the ammonium removal solution effluent while brine is introduced through the zirconium phosphate sorbent module.
24 . The system of any of claims 14 - 23 , further comprising a reservoir ( 107 ) fluidly connectable to the effluent line, the at least one ammonia sensor determining the total ammonia content of the ammonium removal solution effluent in the reservoir.
25 . The system of any of claims 14 - 23 , wherein the at least one ammonia sensor is in the effluent line.
26 . The system of any of claims 14 - 25 , further comprising a temperature sensor in communication with the processor.