Does norepinephrine infusion dose influence the femoral-to-radial mean arterial blood pressure gradient in patients with sepsis and septic shock?

The aim of our study is to determine whether there is a clinically important difference between the femoral and the radial site of blood pressure measurements, and to identify whether the vasoactive infusion dose influences the femoral-to-radial mean arterial blood pressure (MAP) gradient. We included 71 patients with sepsis and septic shock, with no comorbidities that may influence the hemodynamic parameters. Simultaneous measurements were registered at the femoral and radial arteries. The agreement between the two sites of recording was tested in the no-norepinephrine, low-norepinephrine, and high-norepinephrine groups, as well as for the whole group. Results show that 75.4% of paired recordings have a gradient of at least 5 mmHg between the femoral and radial recordings. For the measurements that have a gradient more than 5 mmHg, norepinephrine infusion dose was not found to be a determining factor. A better level of agreement was found after carrying out a separate Bland-Altman analysis for the femoral-to-radial and radial-to-femoral gradients. Norepinephrine infusion rate was not found to be a determining factor for the femoral-to-radial MAP gradient in septic and septic shock patients. Measurement of MAP at the radial or femoral site is clinically interchangeable for most of these patients.