Abstract: A hand held completely self-contained and shirt pocket size oxygen analyzer for secondary monitoring of oxygen percentage is formed of a housing that contains display and control electronics and a visible display screen. The housing is shaped to form an integral handle and receptacle section for manipulation of a hollow elongated cylindrical configuration having an open end that receives a cylindrical oxygen sensor. The integral cylindrical receptacle section together with the oxygen sensor are arranged to be snugly received in a T-section fitting that is placed in tubing that is connected for inhalation therapy.

Abstract: A telescoping guard for a hypodermic syringe needle assembly has an inner section that is securely connected to the upper section of a standard needle assembly hub. The guard can be telescopically extended to afford full protection for the cannula of the needle assembly, and can be contracted to clear the cannula for use without any interference with the syringe barrel. The guard allows use of a standard cannula cap on the standard needle assembly.

Abstract: A syringe for sampling blood has a handle driven plunger in which is mounted an air permeable filter in communication with a valve chamber. In the chamber is mounted a gravity driven steel ball that is heavy enough to enable the syringe to be used in aspiration, with the ball remaining seated to block the air flow through the valve, and yet light enough to be used in taking of a normal pressure arterial blood sample during which air flow through the filter will drive the ball from its seat.

Abstract: A syringe comprises a main tubular body, the body being open at one end and receiving a hypodermic needle at the other end, and a plunger, one end of the plunger extending into the body, through the open end thereof, the plunger having a longitudinal passageway therein permitting air flow therethrough. A fluid-tight seal is formed between the outside surface of the plunger and the inside surface of the syringe body. An air permeable filter member extends across the first end of the plunger, in the passageway, whereby the body can fill with blood, causing the air in the body to pass through the filter member to the open end of the body. The blood does not flow through the filter. A valve extends across the passageway and allows the syringe to be used to aspirate in the absence of natural blood pressure.

Abstract: A syringe comprises a main tubular body, the body being open at one end and receiving a hypodermic needle at the other end, and a plunger, one end of the plunger extending into the body, through the open end thereof, the plunger having a longitudinal passageway therein permitting air flow therethrough. A fluid-tight seal is formed between the outside surface of the plunger and the inside surface of the syringe body. An air permeable filter membrane extends across the first end of the plunger, in the passageway, whereby the body can fill with blood, causing the air in the body to pass through the membrane to the open end of the body. Upon contact with the blood, the membrane swells and seals, automatically stopping the flow of blood. A one way valve extending across the passageway allows the syringe to be used to aspirate in the absence of natural blood pressure.