High flow rate infusion unit and heat exchanger

Abstract

A high flow rate infusion unit includes a heating unit with opposing, electrically-operated heating plates that contact a heat exchanger to heat infusate flowing therethrough. Pressure infusers on the infusion unit are operable to provide infusate at a high flow rate. A flat, elongate heat exchanger has a laminar fluid flow path receivable between the heating plates to which heat is conducted by contact with the heating plates. A bubble trap and a valve are disposed within the heat exchanger. The bubble trap collects bubbles and vents air from infusate exiting the fluid flow path, and the valve shuts off the flow of infusate if the volume of air in the bubble trap exceeds a predefined limit.

1 . An infusion system, comprising
 an infusion unit with heating plates, a slot opening to space between the heating plates, and a mounting block near the opening;   a heat exchanger including a fluid container receivable through the slot for seating in contact with the heating plates, a housing attached to the fluid container and receivable on the mounting block, a laminar flow path in the fluid container, a bubble trap in the housing in fluid communication with the laminar flow path and a valve in the housing in fluid communication with the bubble trap;   the infusion unit including at least one air sensor positioned to be adjacent the bubble trap when the housing is received on the mounting block;   the infusion unit including a valve actuator positioned to be adjacent the valve when the housing is received on the mounting block; and   means in the infusion unit for pressurizing bags of infusate.   
   
   
       2 . The infusion system of  claim 1 , wherein the at least one air sensor includes two ultrasonic sensors mounted to the mounting block, the infusion system further including two sensor couplers mounted to the housing to be in contact with the sensors when the housing is received on the mounting block. 
   
   
       3 . The infusion system of  claim 2 , wherein the valve includes a membrane mounted to the housing, and the valve actuator includes a piston for acting through the mounting block against the membrane when the housing is received on the mounting block. 
   
   
       4 . The infusion system of  claim 1 , further comprising means acting between the mounting block and the housing to latch the housing to the infusion unit, and means on the infusion unit for retaining the housing adjacent the mounting block. 
   
   
       5 . The infusion system of  claim 1 , wherein the housing shrouds the opening when the housing is received on the mounting block. 
   
   
       6 . The infusion system of  claim 5 , further comprising means acting between the mounting block and the housing to latch the housing to the infusion unit. 
   
   
       7 . The infusion system of  claim 6 , further comprising means on the infusion unit for guiding the housing to a seating position adjacent the mounting block. 
   
   
       8 . The infusion system of  claim 7 , wherein the at least one air sensor includes two ultrasonic sensors mounted to the mounting block, the infusion system further including two sensor couplers mounted to the housing to be in contact with the sensors when the housing is received on the mounting block. 
   
   
       9 . The infusion system of  claim 6 , wherein the at least one air sensor includes two ultrasonic sensors mounted to the mounting block, the infusion system further including two sensor couplers mounted to the housing to be in contact with the sensors when the housing is received on the mounting block. 
   
   
       10 . The infusion system of  claim 6 , wherein the valve includes a membrane mounted to the housing, and the valve actuator includes a piston for acting through the mounting block against the membrane when the housing is received on the mounting block. 
   
   
       11 . The infusion system of  claim 1 , the infusion unit further including means connected to the at least one air sensor for detecting air in the bubble trap. 
   
   
       12 . The infusion system of  claim 11 , the infusion unit further including means connected to the valve actuator for closing the valve when air is detected in the bubble trap and for opening the valve when air is not detected in the bubble trap. 
   
   
       13 . The infusion system of  claim 11 , the infusion unit further including means for sensing presence of the heat exchanger. 
   
   
       14 . The infusion system of  claim 13 , wherein the valve includes a valve membrane mounted to the housing and the valve actuator includes a piston for being moved to a retracted position away from the valve membrane or an extended position against the valve membrane, the infusion unit further including means connected to the valve actuator for moving the piston to the retracted position when no heat exchanger presence is detected, and for moving the piston to the extended position when heat exchanger presence is detected. 
   
   
       15 . The infusion system of  claim 14 , the means connected to the valve actuator further for moving the piston to the extended position to close the valve when air is detected in the bubble trap and for moving the piston to the retracted position to open the valve when air is not detected in the bubble trap. 
   
   
       16 . The infusion system of  claim 1 , wherein the infusion unit includes means for releasing a heat exchanger from the infusion unit. 
   
   
       17 . The infusion system of  claim 16 , wherein the means for releasing include means for pneumatically releasing a fluid container from between the heating plates. 
   
   
       18 . The infusion system of  claim 3 , wherein the infusion unit includes a release button and means responsive to the release button for releasing a fluid container from between the heating plates and for moving the piston away from the membrane. 
   
   
       19 . The infusion system of  claim 1 , wherein the infusion unit includes a manually operable release element and means for releasing a heat exchanger from the infusion unit in response to operation of the release element. 
   
   
       20 . The infusion system of  claim 19 , wherein the valve actuator includes a piston for engaging the valve, the means for releasing include means for releasing the piston from engagement with the valve and means for pneumatically releasing a fluid container from between the heating plates. 
   
   
       21 . A high flow rate infusion unit for use with a heat exchanger including a fluid container with a laminar flow path, a bubble trap in fluid communication with the laminar flow path, and a valve in fluid communication with the bubble trap, the high flow rate infusion unit comprising:
 a casing;   opposed heating plates disposed in the casing;   an opening through the casing for seating the fluid container between and in contact with the heating plates;   a mounting block on the casing near the opening for supporting the heat exchanger while the fluid container is seated;   pressure infusers mounted on the casing;   sensor means acting through the mounting block for sensing fluid in the bubble trap;   valve actuator means acting through the mounting block for opening and closing the valve; and   means in the casing for pressurizing a bag of infusate in either pressure infuser.   
   
   
       22 . The infusion unit of  claim 21 , the sensor means including at least one transmit/receive sensor. 
   
   
       23 . The infusion unit of  claim 21 , further including control means responsive to sensing air in the bubble trap for causing the valve actuator means to close the valve and for causing the means for pressurizing to release pressure on the bag of infusate. 
   
   
       24 . The infusion unit of  claim 21 , wherein the heating plates are vertically disposed in the casing, further including opposing pairs of elongate grooves in facing surfaces of the heating plates, each pair defining a respective elongate channel. 
   
   
       25 . The infusion unit of  claim 24 , further including rounded ends of the opening, each aligned with a respective elongate channel. 
   
   
       26 . The infusion unit of  claim 21 , further comprising means for latching the heat exchanger to the mounting block and means on the casing for retaining the bubble trap adjacent the mounting block. 
   
   
       27 . The infusion unit of  claim 21 , further including a major surface on the mounting block facing the opening, wherein the sensor means include at least one ultrasonic sensor mounted in the mounting block. 
   
   
       28 . The infusion unit of  claim 21 , wherein the valve actuator means includes a piston for acting through the mounting block against a valve membrane in the valve. 
   
   
       29 . The infusion unit of  claim 21 , further including means connected to the sensor means for detecting air in the bubble trap. 
   
   
       30 . The infusion unit of  claim 29 , further including means connected to the valve actuator means for closing the valve when air is detected in the bubble trap and for opening the valve when no air is detected in the bubble trap. 
   
   
       31 . The infusion unit of  claim 29 , the infusion unit further including means for sensing presence of the bubble trap and proper alignment of the valve with the valve actuator. 
   
   
       32 . The infusion unit of  claim 31 , wherein the valve actuator means include a piston for being moved to a retracted position away from the valve or an extended position against the valve, further including means connected to the valve actuator means for moving the piston to the retracted position when no heat exchanger presence is detected, and for moving the valve to the extended position when heat exchanger presence is detected. 
   
   
       33 . The infusion unit of  claim 32 , the means connected to the valve actuator means further for moving the piston to the extended position to close the valve when air is detected in the bubble trap and for moving the piston to the retracted position to open the valve when air is not detected in the bubble trap. 
   
   
       34 . The infusion unit of  claim 21 , further including means for releasing the heat exchanger from the infusion unit. 
   
   
       35 . The infusion of  claim 34 , wherein the means for releasing include means for pneumatically releasing the fluid container from between the heating plates. 
   
   
       36 . The infusion unit of  claim 21 , further including a manually operable release element and means for releasing a heat exchanger from the infusion unit in response to operation of the release element. 
   
   
       37 . The infusion system of  claim 36 , wherein the means for releasing include means for releasing the actuator from engagement with the valve and means for pneumatically releasing the fluid container from the unit.