System and method for more complete removal of separated blood components from a separator
The pressure of fluid being conveyed through a fluid flow path during a biological fluid procedure is detected during the procedure. The fluid is conveyed through the fluid flow path 1) at a first pre-determined rate if pressure is zero to a first pressure threshold; 2) at the first pre-determined rate if pressure is greater than the first pressure threshold but less than or equal to a second pressure threshold and if an immediately preceding rate is equal to the first pre-determined rate; 3) at a second pre-determined rate if pressure is greater than the first pressure threshold but less than or equal to the second pressure threshold and if an immediately preceding rate is equal to the second pre-determined rate; and 4) at the second pre-determined rate if pressure value is greater than the second pressure threshold but less than or equal to a third pressure threshold.
1 . A blood processing device configured for use in combination with a fluid flow circuit including a separator fluidically connected to an additive solution container, the blood processing device comprising:
a pump assembly;
a blood separator mounting station and drive unit; and
a controller programmed to implement a blood processing procedure including
controlling the pump assembly during a separation phase to convey blood into a separator mounted to the blood separator mounting station and drive unit, controlling the blood separator mounting station and drive unit during the separation phase to separate the blood in the separator into plasma and red blood cells, and controlling the pump assembly during the separation phase to convey a first portion of the plasma out of the separator and convey a first portion of the red blood cells out of the separator,
controlling the pump assembly during a follow-through phase to convey an additive solution into the separator so as to convey a second portion of the plasma out of the separator after said first portion of the plasma has been conveyed out of the separator and convey a second portion of the red blood cells out of the separator after said first portion of the red blood cells has been conveyed out of the separator,
controlling the pump assembly during a fluid flush phase to convey the additive solution into the separator so as to convey a third portion of the red blood cells out of the separator after said second portion of the red blood cells has been conveyed out of the separator, and
controlling the pump assembly during an air flush phase to convey air into the separator so as to convey a fourth portion of the red blood cells out of the separator after said third portion of the red blood cells has been conveyed out of the separator.
2 . The blood processing device of claim 1 , wherein the controller is further programmed to control the pump assembly to convey the additive solution into a red blood cell collection container during the separation phase.
3 . The blood processing device of claim 2 , wherein the controller is further programmed to control the pump assembly to add the additive solution to the red blood cells at a location upstream of the red blood cell collection container and downstream of the separator via an additive flow path during the separation phase.
4 . The blood processing device of claim 3 , further comprising a valve associated with the additive flow path, wherein the controller is further programmed to control the valve to close during the follow-through phase.
5 . The blood processing device of claim 1 , wherein the controller is further programmed to control the pump assembly during the follow-through phase to not convey blood into the separator.
6 . The blood processing device of claim 1 , wherein the controller is further programmed to control the pump assembly during the fluid flush phase to not convey plasma from the separator.
7 . The blood processing device of claim 1 , wherein the controller is further programmed to
control the pump assembly to convey blood from a source container into the separator during the separation phase, and
control the pump assembly to convey air from the source container into the separator during the air flush phase.
8 . The blood processing device of claim 1 , wherein the controller is further programmed to control the pump assembly during the air flush phase to not convey plasma from the separator.
9 . The blood processing device of claim 1 , further comprising a pressure sensor configured to detect a pressure of fluid flow through a leukofilter positioned downstream of the separator.
10 . The blood processing device of claim 9 , wherein the controller is further programmed to
receive signals from the pressure sensor that are indicative of the pressure of fluid flow through the leukofilter, and
dynamically adjust an operational rate of the pump assembly based at least in part on said signals.
11 . A controller-implemented method of separating blood in a fluid flow circuit including a separator fluidically connected to an additive solution container, the method comprising:
controlling a pump assembly during a separation phase to convey blood into a separator mounted to a blood separator mounting station and drive unit, controlling the blood separator mounting station and drive unit during the separation phase to separate the blood in the separator into plasma and red blood cells, and controlling the pump assembly during the separation phase to convey a first portion of the plasma from the separator and convey a first portion of the red blood cells from the separator,
controlling the pump assembly during a follow-through phase to convey an additive solution into the separator so as to convey a second portion of the plasma from the separator after said first portion of the plasma has been conveyed from the separator and convey a second portion of the red blood cells from the separator after said first portion of the red blood cells has been conveyed from the separator,
controlling the pump assembly during a fluid flush phase to convey the additive solution into the separator so as to convey a third portion of the red blood cells from the separator after said second portion of the red blood cells has been conveyed from the separator, and
controlling the pump assembly during an air flush phase to convey air into the separator so as to convey a fourth portion of the red blood cells from the separator after said third portion of the red blood cells has been conveyed from the separator.
12 . The method of claim 11 , wherein said controlling the pump assembly during the separation phase includes controlling the pump assembly to convey the additive solution into a red blood cell collection container.
13 . The method of claim 12 , wherein said controlling the pump assembly during the separation phase includes controlling the pump assembly to add the additive solution to the red blood cells at a location upstream of the red blood cell collection container and downstream of the separator via an additive flow path.
14 . The method of claim 13 , wherein said controlling the pump assembly during the follow-through phase includes controlling the pump assembly to not convey fluid through the additive flow path.
15 . The method of claim 11 , wherein said controlling the pump assembly during the follow-through phase includes controlling the pump assembly to not convey blood into the separator.
16 . The method of claim 11 , wherein said controlling the pump assembly during the fluid flush phase includes controlling the pump assembly to not convey plasma from the separator.
17 . The method of claim 11 , wherein
said controlling the pump assembly during the separation phase includes controlling the pump assembly to convey blood from a source container into the separator, and
said controlling the pump assembly during the air flush phase includes controlling the pump assembly to convey air from the source container into the separator.
18 . The method of claim 11 , wherein said controlling the pump assembly during the air flush phase includes controlling the pump assembly to not convey plasma from the separator.
19 . The method of claim 11 , wherein
red blood cells exiting the separator pass through a leukofilter, and
the method includes detecting a pressure of fluid flow through the leukofilter using a pressure sensor.
20 . The method of claim 19 , further comprising dynamically adjusting an operational rate of the pump assembly based at least in part on the pressure of fluid flow through the leukofilter.