Factor XII

History[edit]

Hageman factor was first discovered in 1955 when a routine preoperative blood sample of the 37-year-old railroad brakeman John Hageman (1918) was found to have prolonged clotting time in test tubes, even though he had no hemorrhagic symptoms. Hageman was then examined by hematologist Oscar Ratnoff, who found that Hageman lacked a previously unidentified clotting factor.^[22] Ratnoff later found that the Hageman factor deficiency is an autosomal recessive disorder, after examining several related people who had the deficiency. Paradoxically, pulmonary embolism contributed to Hageman's death after an occupational accident in 1968. Since then, case studies and clinical studies identified an association between thrombosis and Factor XII deficiency. Hepatocytes express blood coagulation factor XII.^[23]


Currently produced QuikClot products, produced and marketed primarily for use in battlefield medicine to treat penetrating trauma (such as gunshot wounds and stab wounds), and other injuries that are known to commonly cause exsanguination (such as blast injury), are used with the overarching goal of increasing the time between the blood loss occurring, and the patient succumbing to the blood loss. The purpose of increasing this time is so that the patient may reaching a higher level of medical care before succumbing from their injuries. These products use a Kaolinite-based coating, applied to the bandages by the manufacturer before packaging and sale. This coating, when applied to an open wound via the application of the bandages, directly promotes blood clotting by activating Factor XII in the coagulation cascade.^[24] Also, due to the active ingredient nature of Kaolinite, the activation of the Factor XII occurs in both an earlier amount of time than it otherwise would, and at an increased, more rapid rate than it otherwise would.^[25][26] This coating is widely considered amongst combat medics to be vastly superior to the older QuikClot powder formulation, which was poured into wounds, due to the fact that the older formulation used bead-form Zeolite, a mineral which promotes the coagulation cascade, due to the fact that the reaction between the Zeolite powder and the blood inside the wound site was an Exothermic one, sometimes so intensely that it caused cases of second degree burns on the inside surface of the wound. This, obviously, caused extreme pain to the patient, often more-so than the initial injury was causing them at the time (assuming the patient was still conscious at the time of the application of the powder).^[27] This effect is often seen in movies and TV programs, with the QuikClot powder being poured into wounds, and the patient screaming out in pain as their wounds were violently burned on the inside surface of the wounds. This created a common misconception, which persists to this day, that commonly used QuikClot products still use this method of clot promotion (Zeolite powder) to this day. However, Zeolite-based clotting products are no longer widely used by militaries and police departments throughout the western world, as they have been widely supplanted by the Kaolinite-based bandage products, which do not cause any exothermic reaction whatsoever, nor do they have the absolute-requirement of the application of the product exclusively to the inside-surface of the wound.