Comparison between respiratory variations in pulse oximetry plethysmographic waveform amplitude and arterial pulse pressure during major abdominal surgery.

Background: To assess preload dependence, the variation of the plethysmographic waveform of pulse oximetry (ΔPOP) has been proposed as a surrogate of the pulse pressure variation (ΔPP). The aim of the study was to assess the ability of the pulse oximeter-derived plethysmographic analysis to accurately trend ΔPP in patients undergoing major abdominal surgery by using standard monitors.

Methods: A continuous recording of arterial and plethysmographic waveform was performed in 43 patients undergoing abdominal surgery.

Evaluation of perioperative risk in elderly patients.

From a medical point of view, aging is characterized by a potential failure to maintain homeostasis under conditions of physiological stress. This failure is associated with an increase in vulnerability. Physiological changes associated with aging are progressive but concomitant injury or diseases may rapidly worsen the health status of the patient.