High flow rate infusion unit and heat exchanger
View Patent ↗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. A method for operating an infusion unit with heating plates in combination with a fluid container having a laminar flow path and a housing attached to the fluid container, the housing containing a bubble trap and a valve, the bubble trap in fluid communication with the laminar flow path and the valve in fluid communication with the bubble trap to provide warmed infusate at a high flow rate, comprising:
providing a signal indicating that the fluid container is seated in the infusion unit;
providing a flow of pressurized infusate to the laminar flow path from a source of infusate in response to the signal indicating that the fluid container is seated in the infusion unit;
fanning the flow of infusate into a laminar sheet of infusate in the laminar flow path;
heating infusate in the laminar flow path by conduction from the heating plates;
conducting warmed pressurized infusate from the laminar flow path to the bubble trap and through the valve;
sensing fluid in the bubble trap with a sensor positioned at a first location adjacent the housing; and
an actuator closing the valve if the sensor senses air in the bubble trap; otherwise,
the actuator opening the valve if the sensor senses infusate in the bubble trap.
2. The method of claim 1 , further comprising:
receiving a signal to cease operation;
the actuator closing the valve in response to the signal to cease operation.
3. The method of claim 2 , further comprising:
receiving a signal to release the fluid container; and
the infusion unit dislodging the fluid container from the heating plates in response to the signal to release the fluid container.
4. The method of claim 3 , wherein dislodging the fluid container includes providing a jet of air against the fluid container.
5. The method of claim 4 wherein the jet of air is provided through a heating plate.
6. The method of claim 1 , wherein sensing fluid in the bubble trap includes ultrasonically sensing.
7. The method of claim 1 , wherein sensing fluid in the bubble trap includes sensing with an ultrasonic sensor.
8. The method of claim 1 , further comprising:
installing the fluid container in contact with the heating plates; and,
the housing being latched to the infusion unit by the act of installing.
9. The method of claim 8 , wherein the act of installing includes:
sliding the fluid container into position between the heating plates;
positioning the laminar flow path for heat exchange;
locating the bubble trap for sensing by the sensor; and
orienting the valve for opening and closing.
10. The method of claim 1 , wherein the infusion unit includes a controller, the method further comprising:
the controller monitoring infusate temperature; and,
the controller stopping operation of the infusion unit in response to the infusate temperature exceeding a threshold temperature.
11. The method of claim 10 , further comprising the controller executing a temperature control function to maintain the infusate temperature at a set point value.