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Updated: May 19, 2026

Doppler Ultrasound-Based Leg Blood Flow Assessment During Single-Leg Knee-Extensor Exercise in an Uncontrolled Setting
Published on: December 15, 2023
Blood flow velocity and vascular resistance during passive leg exercise in the critically ill patient
Anneli Thelandersson1, Reinhard Volkmann, Asa Cider
1Department of Physical Therapy, Sahlgrenska University Hospital, Gothenburg, Sweden. anneli.thelandersson@vgregion.se
Abstract:
Passive range of motion exercise is a very common physical therapy treatment for patients admitted to an intensive care unit. However is the knowledge scarce regarding its impact on blood circulation in the extremities. The objective of this study was therefore to investigate the effect of passive range of motion on arterial peripheral leg blood flow velocity (BFV) and vascular resistance. A cross-sectional consecutive study of twelve patients admitted to an intensive care unit and twelve healthy age- and gender-matched controls was conducted. Passive range of motion was performed in one leg by a physical therapist. Blood flow velocities and resistance index in the common femoral artery (CFA), blood pressure and heart rate were measured before, directly after and at rest after passive range of motion. No changes were seen in BFV or resistance index in the patient group or the control group. No changes were found in blood pressure or heart rate in the patient group. In the control group, changes were found in systolic and mean blood pressure, with a higher pressure before passive range of motion. The controls had lower BFV and higher resistance index than the patients when comparing the groups. The conclusion of this study including twelve patients is that passive range of motion does not alter BFV or resistance index in the CFA in comatose and/or sedated critically ill patients.
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