As far as the medical side of this, leeches inject a very complex *local* anticoagulant mix into their host, to keep their blood flowing in the area, plus lots of other chemicals that do all sorts of interesting things.
“Their saliva has over 100 bioactive substances that are very beneficial. One such component is hirudin, which acts as an anticoagulation agent. Calin is another component that also inhibits blood coagulation. A component that dissolves fibrin clots as well as inhibits the formation of thrombus is the destabilase. Leech saliva also contains a Factor Xa inhibitor, and this compound restrains the coagulating effect of the coagulation Factor Xa. It also has hyaluronidase that enhances the viscosity of the interstitial fluid. For vasodilating effect, it has acetylcholine and histamine-like substances as well as carboxypeptidase A inhibitors. These three can increase blood flow by dilating constricted vessels. These are just some of the very useful components in leech saliva.
“Those mentioned above all work together to decrease the viscosity of the blood, making its consistency thinner so as to promote better blood flow. Blood that has a thick consistency makes it prone to clot formation as well as increases the blood pressure of an individual. These clots can travel to different parts of the body and block a vessel, which could then cause a stroke or heart attack. Thick blood poses a risk that the distal extremities, especially the tips of the fingers and toes, will not receive adequate oxygenated blood and the nutrients they need. Therefore, the anticoagulation component in leeches saliva is vital as it naturally makes the blood thinner and works to inhibit platelet coagulation.
“Patients with cardiovascular disease undergo leech therapy on different areas of their body than, lets say, patients with peripheral vascular disease. In each case leeches will promote better blood flow to the region.”
Blood flow can be increased by leeches anti-coagulate properties.(Stops blood from clotting) They have been successfully used in the reattachments of fingers.
(According to the apothecaries at Williamsburg, they also increase white blood cells counts to fight infection. So did injesting Mercury. YUM! Love historical medicine!)
But impeded blood flow for 2 years to the retina or brain causes permanent damage that I don’t see how anti-coags can fix now.
Can’t even figure out why a fall down the stairs would cause blindness unless brain damage but MAYBE son trying to gouge his dads eye has something to do with this. That has nothing to do with blood flow. The cornea, which the kid probably, presumptively gouged doesn’t have a blood supply. This doesn’t make sense at all.
The biggest leeches this guy has to deal with is his lawyers.