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Current time:0:00Total duration:6:14

Video transcript

if you've ever gotten your blood pressure measured before I'm sure you've heard a number like 120 over 80 right well what are those two numbers mean well let's start with the unit's because these aren't just numbers right usually it comes along with units like mmHg which mean millimeters of mercury where the hg is what's used to abbreviate mercury i know why hg right well it's named after this Latin word for liquid silver so it's essentially Latin and so millimeters of mercury is the standard unit used to present somebody's blood pressure okay so this first number this top number is known as your systolic blood pressure remember that systole is the phase of the heart cycle where the heart contracts in pumps out blood or simply during a heartbeat so you've got your two ventricles your left in your right ventricles and win those squeeze and get smaller they actually eject blood out to your circulatory system right and when this happens when the Bloods forced through the blood vessels pressure is going to be generated in those blood vessels and this is what we call your systolic blood pressure the lower number in this case eighty millimeters of mercury is called the diastolic pressure now we can figure out what that is by its name it's the pressure in the blood vessels during diastole and again remember that diastole is when the heart's relaxing so this is the pressure in the blood vessels between beats when the heart is relaxing so it's like contraction systolic pressure and then relaxation diastolic pressure pretty easy so I'm going to draw out these two gauges one's for systolic pressure and the others for diastolic pressure so let's say that my blood pressure was measured at 115 over 75 millimeters of mercury so I'm right about here on our gauge really anything sort of below 120 in the systolic range we're just going to draw as like this green zone so you're sort of safe from hypertension in this zone now that's not to say that like a pressure of 15 millimeters mercury is a good thing what I mean is that you wouldn't have hypertension or you wouldn't have high blood pressure so usually around 120 is considered an average systolic blood pressure along the same lines right around 80 millimeters of mercury on the diastolic side while the heart's relaxing is considered average on the diastolic side and so if it's below 80 millimeters of mercury then we'd say that there would be no hypertension so this again is in kind of the green zone for hypertension so now let's say my pressure was a little higher maybe 130 over 85 so over here on the systolic side we're above the green zone now so in this zone up to about 140 millimeters of mercury it's still not hypertension but it's like it's getting close it's like we're getting there so let's make that zone yellow and this zone actually is referred to as pre hypertension so it's like before hypertension and so the same goes for diastolic pressure our yellow pre-hypertensive zone or stage is between 80 and 90 millimeters of mercury now it's important to note that these yellow zones aren't like this hard and fast rule it's more based on averages and is like this sort of warning sign that the blood pressure is maybe slightly elevated and it's possible it could lead to hypertension in the future especially if this is combined with unhealthy lifestyle like no exercise or poor diet okay so with that said in general hypertension is defined as a blood pressure greater than 140 over 90 so let's draw that as this kind of reddish zone above 140 so if my blood pressure was 150 over 100 which is right here on the systolic and right here on the diastolic we see that that would be considered hypertension right so to be more specific though that would be considered this stage 1 hypertension which is this zone on the systolic side from 140 to 160 and then over here on the diastolic side from about 90 to 100 now there are only two stages so stage two is really anything above 160 on a systolic side and 100 on the diastolic side so for example again if my blood pressure was 170 over 110 that would be stage 2 hypertension now let's say my blood pressure is measured at 150 over 85 okay I can figure that out looks like over here it's 150 so it falls into stage 1 hypertension but then over on the diastolic side 85 is in the pre hypertension stage well it gives is that possible yeah absolutely we even have a special name for this and it's called isolated systolic hypertension that sort of makes sense though right because the hypertension is isolated to the systolic blood pressure usually this is described as systolic blood pressure in the stage 1 or above zones so above 140 and then a diastolic pressure below the hypertension zone this sort of isolated systolic hypertension is more common in the elderly and is actually associated with an increased risk of cardiovascular complications and I'm sure you can see where I'm going next right what if my blood pressures measured at 130 over 105 so I'm in the pre hypertension range for systolic and stage 2 hypertension for diastolic as you probably guess this is known as isolated diastolic hypertension so the hypertension is limited to the diastolic pressure only this one's actually more common in younger patients that tend to be obese or overweight however it's not typically associated with underlying cardiovascular complications like isolated systolic hypertension is