WHAT I DO
Possible Future Method to Prevent
Transfusion Associated Hyperkalemia
Chisa Yamada, M.D.
Transfusion Medicine
Background
 Hyperkalemia is a life-threatening possible
complication of blood transfusion, associated
with the development of arrhythmias leading to
cardiac arrest.
 Stored RBCs in 4 °C leak intracellular K due to
the inhibition of the membrane ATP pump and
decreased ATP.
 Gamma irradiation increases K leak further.
Biochemical Change
of Stored Red Blood Cells
(Technical Manual, 15th edition)
Age of the Units and Potassium
K concentration (mmol/L)
80
70
60
50
Irradiated Units
Non-irradiated
Units
40
30
20
10
0
0
20
40
Age of RBC unit (days)
60
80
Recovery of cellular K at 37°C
Likely mediated by Na-K pump, and Na-K-Cl cotransport
(Brugnara, et al. Transfusion 1992; 5032(3):246252)
Patients at Risk
 Any patient who needs rapid and massive
transfusions, especially those with small total
blood volume such as neonates
Children:
Adults:
Cardiac surgery
CV by-pass circuit prime
Extracorporeal membrane oxygenation
Exchange transfusion
Trauma
Trauma
Liver transplant surgery
Potassium Infusion Rates
 Daily K infusion recommendation for neonates

2 – 3 mEq/Kg/24 hr = 0.0014 – 0.0021 mEq/Kg/min
 K dose by 42 d old AS-3 RBC transfusion



10 mL RBC transfusion to 1 Kg infant in 3 hours
 0.0010 mEq/Kg/min
50 mL RBC transfusion to 1 Kg infant in 1 hour
 0.0153 mEq/Kg/min
50 mL RBC transfusion to 1 Kg infant in 1 hour
– How much K concentration is acceptable?
 6.3 mEq/L
Age of the Units and Potassium
K concentration (mmol/L)
80
70
60
50
Irradiated Units
Non-irradiated
Units
40
30
20
10
0
0
20
40
Age of RBC unit (days)
60
80
Current Effort
 Fresher units (<5-7 day old)

Not always available.
 Washing




With 1-2 L of normal saline
Up to 20% of RBCs may be lost.
Takes up to 1 hour.
Use within 24 hours after washing.
– Normal saline re-suspended RBCs do not store well.
– K re-accumulates in normal saline.
– Need washing relatively short period prior to transfusion.
 Timing of irradiation

Up to the facility.
Recommendations from
Society of Pediatric Anesthesiology
1. Transfuse fresh RBC (<7 days old) in massive
transfusion cases.
2. Transfuse the irradiated blood as soon as possible.
3. If only RBC units with relatively high K are available,




Avoid a hypovolemia-associated low cardiac output state and
replace blood loss early.
Request washed RBC, possible use of Cell Saver ®.
Transfuse slowly with possible >23 gauge peripheral IV rather
than via a central venous catheter.
Check serum electrolytes frequently.
(The Pediatric Anesthesia Quality Improvement initiative 8/16/2011)
Response from AABB
1. The safe concentration of extracellular K in transfused units has
2.
3.
4.
5.
6.
not been determined.
No data is available about K increase in short period after
irradiation.
Washing RBCs requires time which may not be consonant with
rapid blood transfusion situations.
Washing RBCs can induce hemolysis and can increase K
concentration more.
Perioperative salvage technology (e.g., Cell Saver ®) has not
been FDA-approved to wash allogeneic blood at this point.
Additional approaches:



Management and monitoring of K before and during the transfusion.
Use of additive units rather than CPDA-1 units, but safety data for neonates
has not been studied.
Supernatant removal.
(http://www.aabb.org/pressroom/Pages/hyperkalemia110914.aspx)
Future Possibility
 Take out potassium from RBC units by medical
device
Perioperative salvage technology (e.g., Cell
Saver ®) to wash RBC units?
 Small dialysis filter?
 Potassium/Sodium exchange filter?

Potassium Adsorption Filter : KPF-4®
 Developed and approved for use in Japan (KPF-4®,
Kawasumi Laboratories Inc., Tokyo, Japan).
 Made with sodium polystyrene sulfonate resin.
 Mechanism of action : exchanges K with Na.
Potassium Adsorption Filter : KPF-4®
(KPF-4®, Kawasumi Laboratories Inc., Tokyo, Japan)
In Vitro evaluation of efficacy of KPF-4®
 Use leukoreduced AS-3 RBC units of variable
ages (6-61 days)
 One KPF-4® was used to filter three RBC units
with variable flow rates by gravity (18.3-65.9
mL/min)
 10 filters and a total of 30 RBC units,
18 irradiated units and 12 non-irradiated units,
were tested
(Yamada, et al. Transfusion 2010; 50(9):1926-1933)
Potassium (mmol/L)
( Reference range 3.5-5.1 mmol/L )
Pre filtering: 13.7 - 73.5 mmol/L, Post: 0.2 - 16.2 mmol/L
mmol/L
1st Units
2nd Units
3rd Units
80
70
60
50
40
30
20
10
0
Pre
Post
Pre
Post
Pre
Post
(Yamada, et al. Transfusion 2010; 50(9):1926-1933)
Average % Change After Filtering
Unit
Na
K
Cl
Mg
tCa
RBC
Hb
Hct
1 (n=10)
+42.5
-97.5
+12.4
+184.4
+144.2
-6.9
-7.7
-7.2
2 (n=10)
+36.6
-91.2
+0.2
+192.8
+130.4
-1.7
-1.7
-1.6
3 (n=10)
+19.9
-64.4
-0.8
+77.1
+73.6
-1.6
-0.8
-0.9
No change in pH, iCa, plasma Hb, glucose level
(Yamada, et al. Transfusion 2010; 50(9):1926-1933)
Thank you!