Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site brl-tgr.ARPA Path: utzoo!linus!philabs!cmcl2!seismo!brl-tgr!ron From: ron@brl-tgr.ARPA (Ron Natalie) Newsgroups: net.med Subject: Re: blood pressure Message-ID: <5173@brl-tgr.ARPA> Date: Wed, 10-Oct-84 15:27:26 EDT Article-I.D.: brl-tgr.5173 Posted: Wed Oct 10 15:27:26 1984 Date-Received: Fri, 12-Oct-84 05:11:04 EDT References: <3778@tektronix.UUCP> <127@logico.UUCP> Organization: Ballistics Research Lab Lines: 35 Springier? It's not the elasticity of the artery that determines how much pressure it takes to cut off the circulation, it is the pressure of the flow that makes the difference. Systole (indicated by the higher numbers) is an index of how hard the heart is making it's stroke, diastole is the rest (actually, filling) period. The primary reason blood pressure goes up is becuase for some reason the heart is pumping harder to get the same volume of blood through. As your demand for blood contents (oxygen, notably) goes up, the heart has to pump more blood. A more dramatic change happens to the person with the healty heart (not a more serious, just more dramatic) goes into shock. His heart will raise the pressure to keep the volume up until a point is reached and a collapse occurs, while less healthy people will just go into a gradual loosing battle. The rule of thumb is "for an adult male up to age 40, at rest, add his age to 100 for the systolic blood pressure, for females add to 90). Serious low blood pressure indicates shock (loss of volume), high blood pressure indicates the heart is working harder than usual to pump the blood. High blood pressure usually is considered bad because it indicates other problems like arteriosclerosis or it may cause a higher risk of hemmorage due to increased pressure. I don't think anyone claims that blood pressure alone is the problem, but having high blood pressure is a sign for a need for further investigation. Actually, all my experience with blood pressure is emergency medicine based. We use blood pressure as a baseline and watch for changes. We don't condider problems unless the blood pressure is really high (>180) or really low (<80) or it changes drastically. Other indicators like the systolic and diastolic numbers growing closer together idicate a decrease in heart efficiency sometimes due to blood in the pericardium. -Ron w