Abstract: A method of continuously monitoring cardiac output of a patient includes the step of determining a value of a cardiac output constant which is assumed to remain stable over the period of interest and is determined as a function of values of various measured parameters of the patient. These values may include thermodilution cardiac output, carbon dioxide production, arterial and mixed venous oxygen saturation and hemoglobin. Thereafter, cardiac output is continuously determined employing the calculated cardiac output constant and monitored values of carbon dioxide production and arterial and mixed venous oxygen saturation. Oxygen transport may also be monitored on a continuous basis.

Abstract: A safety enhancing, relatively low-cost, needle cover which is integrally bonded to a disposable needle cannula of a hypodermic syringe and adapted to eliminate the handling and/or destruction of the needle after use. The needle cover comprises distally and proximally oriented pairs of needle cover segments which are hingedly interconnected and pivotable relative to one another. The needle cover is collapsible from an open, expanded configuration, with the cannula biased in an armed state for administering an injection of the fluid contents of the syringe, to a closed, generally planar configuration, with the cannula biased in a shielded state completely surrounded, shielded and isolated after use. By virtue of the present invention, the needle cannula can be safely discarded within its collapsible cover while avoiding an accidental needle strike and the spread of a contagious, and possibly life threatening disease.