Xie Z, et al. - In order to determine the variability in radial artery invasive blood pressure associated with arm elevation in patients with different hemodynamic types, researchers analyzed data from 73 general anesthesia hepatobiliary postoperative adult patients admitted to an ICU over a 1-year period. At baseline, and 30 and 60 s after the arm had been raised from 0° to 90°, the value of invasive radial arterial pressure was recorded. Blood pressure was compared before as well as after arm elevation, and between hemodynamically stable, hypovolemic shock, and septic shock patient groups. In an arm elevation test, significantly different radial artery invasive blood pressure changes were demonstrated by hypovolemic shock and septic shock patients. This appeared to be applicable as a new method to distinguish hypovolemic shock and septic shock from hypotension.