A Compelling Case for the Use of Perioperative Zymogen Protein C for Increased Patient Safety.

It is imperative to maintain normal blood flow to provide adequate oxygen supply to specific organs and cells, as well as for the removal of metabolic byproducts. Therefore, any situation that results in blood clotting can injure or kill living tissues. In this paper, we describe a case where a protein C deficient subject who would, by all medical indicators, be at 100 % risk of experiencing thrombophlebitis, deep vein thrombosis, and or lung emboli, is able to escape all pathologies by using perioperative zymogen protein C (ZPC). This protein C deficient patient has a long history of blood clotting, particularly from surgical procedures. The patient is 81 years old and first experienced clotting due to hernia surgery in 1964, when he was hospitalized for 16 days post-surgery with life threatening complications. It was later determined in 1980, after many episodes, that the patient had hereditary protein C deficiency at the 38 % level. In his hernia surgery, perioperative ZPC was used along with accepted anticoagulation procedures with no blood clots or other related side effects occurring. This procedure can greatly benefit protein C deficient patients, and could potentially find use for non-PC deficient patients in surgeries and a variety of other medical treatments. This particular case helps to validate the importance of ZPC in effecting safer surgery in high-risk patients. It also supports the mechanism of ZPC acting as an anticoagulant without causing bleeding. Most importantly, each clinical case study represents a unique combination of surgeon, hematologist, medical staff, and patient functioning as a coordinated team. In this case, smaller amounts of very expensive ZPC achieved safe and efficacious results, which is hugely important for future clinical applications when considering the production cost of ZPC. More studies must be done to establish minimum dosing while achieving safe and efficacious outcomes.

The John Charnley Award: heritable thrombophilia and development of thromboembolic disease after total hip arthroplasty.

UNLABELLED: We retrospectively assessed whether heritable thrombophilia-hypofibrinolysis was more common in patients developing venous thromboembolism after total hip replacement than among control patients who did not develop venous thromboembolism, as an approach to better identify causes of venous thromboembolism after total hip arthroplasty. Twenty patients with proximal deep venous thrombosis after THA and 23 patients with symptomatic pulmonary embolism were compared with 43 control patients who did not have postoperative venous thromboembolism. Five of 42 patients with venous thromboembolism (12%) and 0 of 43 control patients (0%) had antithrombin III deficiency (< 75%). Nine of 42 patients with venous thromboembolism (21%) and 2 of 43 control patients (4.7%) had protein C deficiency (< 70%). Ten of 43 patients with venous thromboembolism (9 heterozygous, 1 homozygous; 23%) and 1 of 43 control patients (heterozygous; 2%) had the prothrombin gene mutation. Patients who had venous thromboembolism after total hip arthroplasty were more likely than matched control patients to have heritable thrombophilia with antithrombin III or protein C deficiency, or homo-heterozygosity for the prothrombin gene mutation. Screening for these three tests of heritable thrombophilia before total hip arthroplasty should improve the identification of patients with a reduced risk of venous thromboembolism who may need only mild thromboprophylaxis, and of those patients with heritable thrombophilia in whom prophylaxis should be more aggressive. LEVEL OF EVIDENCE: Prognostic study, Level II-1 (lesser-quality RCT). See the Guidelines for Authors for a complete description of levels of evidence.