In most people the systolic and diastolic blood pressures are similar in the left and right arms. In some patients there may be a significant difference between them.
interarm difference in systolic blood pressure =
= ABS((SBP in left arm) - (SBP in right arm))
interarm difference in diastolic blood pressure =
= ABS((DBP in left arm) - (DBP in right arm))
Various authors use different cutoffs for a significant difference. Some use > 10 mm Hg, some > 20 mm Hg and some both.
Percent of Population
> 10 mm Hg
> 20 mm Hg
data of Lane et al
Significance of interarm blood pressure difference:
(1) The presence of an inter-arm blood pressure difference may identify a patient at increased risk for coronary artery disease and/or peripheral vascular disease.
(2) A significant difference in blood pressure can occur following surgery or major trauma.
(3) When monitoring blood pressure in these patients the same arm should be used for all readings.
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Purpose: To compare the systolic and diastolic blood pressures in the left and right arm, looking for a significant inter-arm blood pressure difference.
Specialty: Cardiology, Emergency Medicine, Pulmonology
Objective: other testing, criteria for diagnosis