The effects of crossed leg on blood pressure measurement

Background: It is clear that numerous factors influence an individual's blo od pressure measurement. However, guidelines for accurately measuring blood pressure inconsistently specify that the patient should keep feet flat on the floor. Objective: To determine if the crossing of a leg at the knee during blood p ressure measurement has an effect on the patient's blood pressure reading. Methods: A convenience sample of 100 hypertensive male subjects was selecte d from Various outpatient clinics in an inner-city acute-care veterans' hos pital. The first 50 subjects positioned their feet flat on the floor while their blood pressure was measured. After 3 minutes, the blood pressure was measured again with the subject's leg crossed at the knee. The procedure wa s reversed for the second 50 subjects. Results: The results indicated that both systolic and diastolic blood press ure increased significantly (p<.0001) with the crossed leg position. Conclusion: When blood pressure is measured, patients should be instructed to have feet flat on the floor to eliminate a potential source of error.