Abstract: The pCO.sub.2 probe has a miniaturized glass bulb pH sensor concentrically arranged in a flexible, noncollapsible hollow tube. A silicone end cap is expanded in a freon solvent and placed over the end of the tube while the freon evaporates, returning the end cap to its normal contracted size where it forms a tight elastic fit. The pH sensor includes an internal electrode and an outer electrode is concentrically wrapped about the glass bulb so the electrodes are in close proximity. The glass bulb and the chamber defined by the tube walls and silicone membrane are both filled with suitable electrolytes of sufficient volume to minimize air bubbles. Without air bubbles, the electrodes remain emersed in the respective electrolytes regardless of the physical orientation of the probe.

Abstract: A smooth bulbous tip slips within a blood vessel after puncture by an inserted needle. Withdrawal of the needle leaves a blunt, non-lacerating conduit for intravenous fluid. A broad base prevents breakage of the cannula. Multiple break-away perforated tabs provide options for suturing the hub of the catheter to the skin of the patient.