<P> Severely elevated blood pressure (equal to or greater than a systolic 180 or diastolic of 110) is referred to as a hypertensive crisis . Hypertensive crisis is categorized as either hypertensive urgency or hypertensive emergency, according to the absence or presence of end organ damage, respectively . </P> <P> In hypertensive urgency, there is no evidence of end organ damage resulting from the elevated blood pressure . In these cases, oral medications are used to lower the BP gradually over 24 to 48 hours . </P> <P> In hypertensive emergency, there is evidence of direct damage to one or more organs . The most affected organs include the brain, kidney, heart and lungs, producing symptoms which may include confusion, drowsiness, chest pain and breathlessness . In hypertensive emergency, the blood pressure must be reduced more rapidly to stop ongoing organ damage, however, there is a lack of randomised controlled trial evidence for this approach . </P> <P> Hypertension occurs in approximately 8--10% of pregnancies . Two blood pressure measurements six hours apart of greater than 140 / 90 mm Hg is considered diagnostic of hypertension in pregnancy . High blood pressure in pregnancy can be classified as pre-existing hypertension, gestational hypertension, or pre-eclampsia . </P>

Ranges of blood pressure for normal hypertensive and hypotensive