Perhaps Cisco is drifting away like its stock.....I hope not! Karl ----- Original Message ----- From: "Howard C. Berkowitz" To: Sent: Wednesday, May 30, 2001 3:46 PM Subject: Re: O.T : Heart By-pass Surgery...Anyone got any links???? [7:6442] > >Hi, > > > >i have seen recently a vast amount of non-cisco related questions recently > >and i thought that i would try my luck .... > > > >my uncle needs some heart surgery and was wondering if anyone has some > >advise..... > > Well, I'm not sure exactly what you are asking, but both having done > some biomedical engineering and also having been through > angioplasties, bypass, pacemakers, and various research procedures... > > > > >Is it like BGP or OSPF routing when trying to track a blood clott... > >left ventricle first..unless there is a weight on the right... > > No, it's more like static routing. There is also separation of the > control and forwarding planes. > > In the forwarding plane, venous blood (veins flow to the heart, > arteries flow from the heart), enters the right atrium, then to the > right ventricle, then to the lungs, then to the left atrium, then the > left ventricle. Various valves and vessels also are involved. > > Routing loops are Bad Things and need to be corrected surgically. > > The control plane is more like HSRP. The primary biological > pacemaker, or HSRP primary, is in the sinoatrial (SA) node, with a > basic beat frequency of 75. The signal then should go to the > atrioventricular (AV) node, which has a "watchdog timer" and the > ability to act as a pacemaker with a basic frequency of 60. If the > AV node doesn't hear an SA trigger in a certain period, it becomes > the active pacemaker. Similarly, the ventricles also have backup > pacing ability at a rate of about 25. I have a problem between the > SA and AV nodes, and my electronic pacemaker fires off when it > doesn't see the pulse that it thinks it should, giving me a normal > rate of 95. The pacemaker is smart enough to sense physical activity > and turn up the rate if I'm exercising. > > The series of backups doesn't always work correctly. Ventricular > fibrillation, beloved of ER shows, is essentially a condition where > random parts of the ventricles act as their own pacemakers. It's like > a bunch of input interfaces kind of randomly throwing packets around > without even aiming at the right output interface. > > A cardiac catheterization/angiogram is something like a debug, in > that the probe may block vessels while doing its measurements. Stress > tests, which may be done with exercise (treadmills or bicycles) or > with stimulating drugs, are more like extended pings for performance. > > There's actually a very nice page at the NIH Clinical Center, where I > am followed on a research basis: > http://rover.nhlbi.nih.gov/labs/7east/cardtests.htm > > > > > > >are the veins leading to and from the heart like Fibre cables...(heavily > >sheilded) > > > >any advise on this matter would be most helpfull as he is starting to leek > >and scream out in pain....... > > > >Cheers > > > >steve > > > >(sarcasm IS the lowest form of witt..that is why i use it ).... > > > >please Cisco only.... > > > > > > > >_________________________________________________________________________ > >Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. > >FAQ, list archives, and subscription info: > >http://www.groupstudy.com/list/cisco.html > >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=6458&t=6458 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
