Noninvasive detection of the hemodynamic stress of exercise using the photoplethysmogram.

Exercise induced hemodynamic stress has been studied extensively using a wide range of physiological sensors. While athletes can modulate their training intensity using EKG-based heart rate monitors, there are currently no noninvasive monitors that can be used to ascertain with a high degree of certainty the hemodynamic stress an individual is experiencing because of fatigue or an underlying pathology. We propose that cardiac stress will result in detectable changes in skin blood flow.

Detecting exercise induced stress using the photoplethysmogram.

The effect of exercise on the cardiovascular system has been studied extensively using a wide range of physiological sensors. Athletes now commonly use EKG-based monitors to ascertain heart rate, but these devices cannot directly monitor the level of physical stress. We hypothesize that the low frequency spindle waves seen in the photoplethysmographs (PPG) of exercising individuals may be useful for noninvasively detecting hemodynamic stressors to the human vascular system.

Correlation of EUS measurement with pathologic assessment of neoadjuvant therapy response in esophageal carcinoma.

Background: EUS-measured reduction in tumor size after neoadjuvant therapy has previously been correlated with downstaging and improved survival in patients with esophageal cancer. The aim of this study was to determine whether tumor changes measured by EUS correspond to pathologically assessed chemoradiotherapy-induced tumor regression.

Methods: Forty-one patients with esophageal cancer treated with combined modality treatment were studied.

Endosonographic assessment of multimodality therapy predicts survival of esophageal carcinoma patients.

Background: Standard endosonographic (EUS) staging criteria are unreliable for staging esophageal carcinoma after neoadjuvant therapy; however, measurement of tumor size reduction can identify patients who have achieved a pathologic response. In the current study the authors prospectively compared survival between patients classified as responders and those classified as nonresponders by EUS.

Methods: The maximal transverse cross-sectional area of the tumor was measured before and after neoadjuvant therapy in patients who were candidates for multimodality treatment.

Bronchial obstruction after upper lobectomy: kinked bronchus relieved by stenting.

Post resectional kinking of the lower lobe bronchus caused obstructive symptoms in 2 patients following upper lobectomy. Exaggerated upward displacement of the remaining lower lobe seemed to be causative. Intrabronchial stenting relieved the obstruction in each case with satisfactory intermediate term results.