Pulse Oximetry Measurements in the Evaluation of Patients With Possible Thoracic Outlet Syndrome

Abstract

We present our experience in using pulse oximetry as an aid in the diagnosis of thoracic outlet syndrome (TOS). Our attention was given to those symptomatic patients without objective confirmatory data on imaging or electrodiagnostic evaluation. Using a pulse oximeter, we measured the oxygen saturation and the pulse rate during a provocative extremity abduction stress test exercise maneuver in 18 patients with symptoms and signs consistent with a diagnosis of nonspecific neurogenic TOS. The oxygen saturation and pulse rates in 18 asymptomatic subjects were used as a control. Resting oxygen saturation above 97% was present in both groups initially. After the provocative exercise maneuver, there was a significant reduction in the oxygen saturation levels, which dropped to 86% in the symptomatic TOS group compared with 94% in the control group. There was a significant increase in pulse rate in those subjects suspected of having TOS compared with a minimal increase in pulse rate in control subjects. Pulse oximetry produced objective confirmatory measurements, which support a hypothesis that hypoperfusion in the upper limb during provocative activities or exercise may cause disabling symptoms associated with nonspecific neurogenic TOS. This method may be a useful, noninvasive, rapid, and inexpensive clinical tool in the diagnosis of TOS, a condition frequently lacking in objective, confirmatory diagnostic data.