Effect of Valsalva Maneuver on Oxygen Saturation in Patients with Intracardiac Shunts

Abstract

Oxygen saturation of arterial and central venous blood was measured continuously during the Valsalva mnaneuver in patients with and without intracardiac defects. The majority of patients with atrial septal defects and patients with ventricular septal defects and high right ventricular pressure showed a sharp decrease in saturation of radial artery blood shortly after the inaneuver. These changes were not recorded accurately by ear oximnetry. The patients with shunts uniformly showed a rapid increase in saturation of pulmonary artery blood during the initial period of increased airway pressure. This effect was not observed in patients without shunts.

Dye dilution and oximetry for detection of patent foramen ovale

“…Alternative simple and safe methods for the detection of PFO would be useful both in clinical work and in research. Earlier studies demonstrate that small defects in the atrial septum can be detected by using dye dilution techniques (10)(11)(12)(13)(14)(15) and by ear oximetry (16)(17). We investigated if dye dilution method and oximetry with a noninvasive earpiece apparatus are able to detect PFO in young patients who had had an unexplained stroke.…”