Examples of the invention include inhalation systems, breathing apparatuses, and methods for administering a solution by inhalation to a patient. Example breathing apparatuses described herein may be configured to minimize loss of the solution to the environment. Additionally or instead, example breathing apparatuses may be configured to recirculate exhaled solution to increase an amount of the solution available to a patient while minimizing exhausted solution. In some examples, breathing apparatuses may deliver nebulized platelet rich plasma ("PRP").本發明之實例包含用於藉由吸入將一溶液遞送至病患之吸入系統、呼吸裝置及方法。本文所述之實例呼吸裝置可經組態以使損失至環境中之溶液最少化。此外或者替代地，實例呼吸裝置可經組態以使得呼出之溶液再循環，以增加病患可使用之溶液之量，同時使經排放溶液最少化。在一些實例中，呼吸裝置可遞送富含血小板血漿(nebulized platelet rich plasma：PRP)。
