University of Pennsylvania

Other

Gordon R Neufeld

James E Baumgardner

James Edward Baumgardner

Dasan Potti

Bryan E Marshall

Jon L Richter

Peter W Scherer

A method and apparatus for the analysis of blood or other liquids by mass spectrometry to determine the partial pressures of gases and other volatile substances dissolved in the blood or other liquid in a manner independent of the solubility of the gases in the blood or other liquid. A countercurrent membrane exchanger (CCME) is provided for equilibrating a carrier fluid with the sample of blood or other liquid, the output of which is coupled to a tubular direct insertion membrane probe (t-DIMP) type of membrane inlet mass spectrometer. The CCME preferably has complementary spiral grooves on opposing metal plates for the water carrier and sample liquids so as to induce secondary flows which greatly reduce the resistance to equilibration between the liquid sample and water carrier phases. The t-DIMP is characterized by the use of Teflon&#x2122; sleeves specifically to reduce noise introduced at the connection between the silicone membrane in the t-DIMP and the steel tubing for the water carrier, by the use of radiation shields to prevent heating of the silicone membrane and water carrier to allow lower carrier flow rates, and by the heating of the section between the ion source and the vacuum pumps specifically to improve linearity of the t-DIMP.

Membrane countercurrent exchanger and membrane inlet mass spectrometer for the analysis of gas partial pressure in liquid samples

A tongue cleaner having an elongate shank portion for holding thereof and a portion extending from one end thereof for supporting a tongue scraping edge. The support portion is skewed relative to the shank portion to slope downwardly for effecting engagement of the edge with a posterior part of the upper surface of the tongue so that the posterior part may be comfortably scraped.

Tongue cleaner

A gas measurement probe for measuring gas tensions in liquid. The probe comprises a tubing having one end adapted for connection to a gas measurement device, such as a mass spectrometer, a gas chromatograph, an infrared spectrometer or a Raman spectrometer, among others. The second end of the probe is provided with a tip having at least one pore formed in it. The pore is filled with a membrane material which eliminates water from entering, but admits low molecular weight gases. These low molecular weight gases may then be identified by the measurement device.

Probe for the measurement of gas tensions

Cardiac output of a test individual is determined in a noninvasive method, by processing CO.sub.2 expirogram data obtained from the individual. The method also noninvasively determines pulmonary arterial blood CO.sub.2 concentration for the test individual. An apparatus for carrying out this noninvasive method includes a database of computed numerical CO.sub.2 expirograms, a device for measuring experimental CO.sub.2 expirogram data and means for processing the data sets to determine cardiac output.

Noninvasive method and apparatus for determining cardiac output

A mass spectrometer probe comprising a tubing having one end adapted for connection to a spectrometer and a second probe tip having a pore cut therethrough, the pore being sealed with a membrane such that the membrane eliminates water from the mass spectrometer system and admits low molecule weight gases into the system.

Mass spectrometer probe for measurements of gas tensions

A lung water computer system utilizing a single optical detection path. A single beam of visible (VIS) and infra-red (IR) radiation is chopped and filtered in at least two bandwidths centered on the absorption peaks of tracers such as indocyanine green (ICG) and deuterated water (DHO). The chopped, filtered beam is transmitted along the optical detection path to a densitometer cell provided with intersecting fluid and optical channels. The optical channels are milled to provide an accurate optical path length (OPL) across the fluid channel. The chopped filtered radiation traverses blood containing ICG and DHO in the fluid channel and is detected by a two color (VIS and IR) detector at the end of the optical detection path. The VIS and IR outputs of the detector are processed in separate electronic channels. The channels are sampled and the sample data is used to compute optical density, tracer concentration, cardiac output, tracer transit time, recovery factor and lung water according to well-known algorithms. Although not necessary in computing lung water, the channels may be sampled adaptively based on the sample levels or signal to noise ratio (S/N).

Growing community of inventors

Flourtown, PA, United States of America

Gordon R Neufeld