US 5,420,962 A · Convection blood warming system with disposable flattened tube envelope having vent incorporating a hydrophobic filter

Abstract

A system for warming blood or other liquids to body temperature for infusion into a patient. The system includes a blood warmer apparatus having a pair of closely spaced apart heat transfer plates, each of which forms one face of a housing containing flat vapor condensation heating units. A flat disposable heat exchanging blood warming envelope is held clamped between the heat transfer plates. The envelope is provided with an air escape vent covered by a hydrophobic filter eliminating the need for a vent separate check valve. An air heating unit in one of the apparatus housings includes a cool air inlet, heat transfer fins on the walls of the vapor condensation heater unit, a fan and guides for conducting air past those fins and a warmed air outlet. An external elongated insulated air hose is connected at one end to the warmed air outlet and extends to the patient. The blood flow line from the outlet of the heat exchanging envelope is positioned within the warmed air hose to maintain the physiologic temperature of the blood.

Claims19

Dependent claims

A system for warming blood or other liquids to body temperature for infusion into a patient comprising:

A) a blood warmer apparatus having a pair of closely spaced apart heat transfer plates each forming one face of a housing containing flat vapor condensation heating units therein, and adapted to receive a flat heat exchanging blood warming envelope held clamped between said closely spaced apart heat transfer plates,
B) an air heating unit within one of said housings including:
1) a cool air inlet to said housing,
2) heat transfer fins on the wall of the vapor condensation heater unit opposite from the heat transfer plate,
3) a fan and guides within the housing for conducting air from said inlet past said fins, and
4) a warmed air outlet from said housing, and
C) an external outer elongated air hose connected at one end to said warmed air outlet and extending to the patient, said air hose adapted to receive an inner elongated blood flow line therein.

4 more elements

A system for warming blood or other liquids to body temperature for infusion into a patient comprising:

A) a blood warmer apparatus having a pair of closely spaced apart heat transfer plates each forming one face of a housing containing flat vapor condensation heating units therein,
B) a flat disposable heat exchanging envelope held clamped between said closely spaced apart heat transfer plates, said envelope having a blood inlet adapted to be connected to a source of blood to be warmed and a warmed blood outlet adapted to be connected to a flow line to the patient,
C) an air escape vent adjacent the topmost edge of said envelope and a hydrophobic filter covering said vent,
D) an air heating unit within one of said housings including:
1) a cool air inlet to said housing,
2) heat transfer fins on the wall of the vapor condensation heater unit opposite from the heat transfer plate,
3) a fan and guides for conducting air from said inlet past said fins, and
4) a warmed air outlet from the housing,
E) an external outer elongated air hose connected at one end to said warmed air outlet and extending to the patient, and
F) an inner elongated blood flow line within said outer hose, one end of said inner flow line being connected to said warmed blood outlet and the opposite end extending to the patient.

7 more elements

Dependencies are inferred from the claim text.

Convection blood warming system with disposable flattened tube envelope having vent incorporating a hydrophobic filter

Life of this patent

Convection blood warming system with disposable flattened tube envelope having vent incorporating a hydrophobic filter

Life of this patent

Abstract

Claims19