Registered Nurses' Association of Ontario

Important blood pressure definitions

Blood Pressure: measure of the pressure or force of the blood against the walls of the blood vessels. The pressure is measured in millimeters of mercury (mmHg).

Blood pressure is the product of the amount of blood pumped by the heart each minute (cardiac output) and the degree of dilation or constriction of the arterioles (systemic vascular resistance). It is a complex variable involving mechanisms that influence cardiac output, systemic vascular resistance, and blood volume.


Hypertension or High Blood Pressure: medical condition in which blood pressure is consistently above the normal range.


Hypertensive Emergency: may present as an asymptomatic elevation in blood pressure with a diastolic reading >130, or a systolic reading of >200.


Isolated Systolic Hypertension: As adults age, systolic blood pressure tends to rise, and diastolic tends to fall. When the systolic is ≥140, and the diastolic is <90, the individual is classified as having isolated systolic hypertension.


Primary, Idiopathic or Essential Hypertension: persistent and pathological high blood pressure for which no specific cause can  be found .


Secondary Hypertension: hypertension that is caused by another disease. About 5 to 10% of cases of high blood pressure are caused by medical problems such as heart or kidney disease, or as a side effect  of medication .


Target Organ Damage: subclinical vascular lesions and/or functional deterioration of the major target organs (e.g., brain, eye fundus, heart, conduit arteries and kidneys).


White Coat Hypertension: term used to denote individuals who have blood pressures that are higher than normal in the medical environment, but whose blood pressures are normal when they are going about their daily activities. The diagnosis of white coat hypertension can be determined through the use of ambulatory and/or self-home monitoring of blood pressure. The risk of future cardiovascular disease events is less in individuals with white coat hypertension than in those with higher than normal ambulatory blood pressures.

Chronic Disease
Nursing Management of Hypertension
Point of Care Resources