A device for conditioning blood comprising: a heat exchanger module including a heat exchanger fiber layer including heat exchanger fibers configured to receive a heat exchanger fluid and exchange heat with the blood; a gaseous micro-emboli removal module including a micro-porous fiber layer including micro-porous fibers configured to receive atmospheric or sub- atmospheric pressures such that at least some gaseous micro-emboli are drawn from the blood through the micro-porous fibers; a gas exchanger module including a gas exchanger fiber layer including gas exchanger fibers configured to receive a gas mixture and exchange gas with the blood; and a potting material body that embeds the heat exchanger fibers, the micro-porous fibers and the gas exchanger fibers and defines a blood compartment that extends through the heat exchanger module , the gaseous micro-emboli removal module , and the gas exchanger module ; characterized by at least one of: the heat exchanger module including stacked heat exchanger hollow fiber mat layers , wherein the heat exchanger hollow fiber mat layers are alternatively orthogonally angled from one another; the gaseous micro-emboli removal module including stacked micro-porous hollow fiber mat layers , wherein the micro-porous hollow fiber mat layers are alternatively orthogonally angled from one another; and the gas exchanger module including stacked gas exchanger hollow fiber mat layers , wherein the gas exchanger hollow fiber mat layers are alternatively orthogonally angled from one another. a heat exchanger module including a heat exchanger fiber layer including heat exchanger fibers configured to receive a heat exchanger fluid and exchange heat with the blood; a gaseous micro-emboli removal module including a micro-porous fiber layer including micro-porous fibers configured to receive atmospheric or sub- atmospheric pressures such that at least some gaseous micro-emboli are drawn from the blood through the micro-porous fibers; a gas exchanger module including a gas exchanger fiber layer including gas exchanger fibers configured to receive a gas mixture and exchange gas with the blood; and a potting material body that embeds the heat exchanger fibers, the micro-porous fibers and the gas exchanger fibers and defines a blood compartment that extends through the heat exchanger module , the gaseous micro-emboli removal module , and the gas exchanger module ; characterized by at least one of: the heat exchanger module including stacked heat exchanger hollow fiber mat layers , wherein the heat exchanger hollow fiber mat layers are alternatively orthogonally angled from one another; the gaseous micro-emboli removal module including stacked micro-porous hollow fiber mat layers , wherein the micro-porous hollow fiber mat layers are alternatively orthogonally angled from one another; and the gas exchanger module including stacked gas exchanger hollow fiber mat layers , wherein the gas exchanger hollow fiber mat layers are alternatively orthogonally angled from one another. the heat exchanger module including stacked heat exchanger hollow fiber mat layers , wherein the heat exchanger hollow fiber mat layers are alternatively orthogonally angled from one another; the gaseous micro-emboli removal module including stacked micro-porous hollow fiber mat layers , wherein the micro-porous hollow fiber mat layers are alternatively orthogonally angled from one another; and the gas exchanger module including stacked gas exchanger hollow fiber mat layers , wherein the gas exchanger hollow fiber mat layers are alternatively orthogonally angled from one another. <EOS>