A classmate who have be standing still for several hours working on a laboratory experiment suddenly faint.?
Called Postural syncope it occurs among soldiers who stand surrounded by attention for prolonged periods on display. The venous pump in calf muscles fail to return blood from lower extremities to heart thereby causing sudden lowering of blood pressure. This syncope or faint is self limited . Immediately after tip out, blood starts circulating and consciousness is regained.
He shouldn't own locked his knees.
any one know the number for 911?
Your classmate locked his/her knees - this reduces the flow of oxygen to the brain, creating the lightheaded premonition and eventually fainting.
Its essential that your body returns blood posterior from veins to your heart, but because at this point within your circulation the blood pressure is so low, the body has recruit other mechanisms to gain back to the heart. These include valve to prevent back flow, the squeezing of muscles on vein, and changes within internal cavity pressures due to breathing. Because your classmate was standing still for so song, the muscles will not be squeezing the blood fund to the heart, this may have reduced his/her blood pressure slightly. However, usually the body compensates for this by increasing heart rate and does not pose a problem. It is likely that this be also linked to calorie intake, if your classmate have not eaten for a while, blood pressure (from low heart rate due to standing still for so long) within addition blood sugar may own been low, contained by combination, this may have resulted surrounded by the brain executing its safety works to get more blood and nutrients. It unsophisticatedly involves falling on the floor! This is known as faint :)
Possible diabetic, working a long time without snacks or dampen will cause sugar level to drop.
this is a kind of shock which occur due to prolonged standing which reduces the flow of blood to heart from lower extremeties(that is legs) thus reducing the venous return to the heart and ultimately reducing the cardiac output and this reduce blood flow to th brain thus causing faint. i can't recall the designation given to this kind of shock.
Joy is correct. Fainting (syncope) is a form of Neurogenic Shock. If standing is the primary explanation, once the head go below the heart, all should be economically. A short break can save profusely of time! (and secondary injury)