Coronary artery bypass grafting in a patient with protein S deficiency: Perioperative implications

Abstract

Protein S (PS) along with activated protein C plays an important role in the down-regulation of in vivo thrombin generation. Its deficiency can cause abnormal and inappropriate clot formation within the circulation necessitating chronic anticoagulation therapy. The risk of developing thrombotic complications is heightened in the perioperative period in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). Heparin resistance is very rare in these patients, especially when antithrombin levels are near normal. Management of CPB in this scenario is quite challenging. We report the perioperative management, particularly the CPB management, of a patient with type I PS deficiency and incidentally detected heparin resistance, who underwent coronary artery bypass grafting with CPB.

Preventative management against thromboembolism using fresh frozen plasma in a coronary artery bypass graft patient with protein S deficiency: a case report

“…Hence, PS acts as an anticoagulant factor [ 1 ]. The PS activity level is affected by hepatic or renal disorders, vitamin K antagonist (warfarin), chronic infection, pregnancy, disseminated intravascular coagulopathy, and other conditions, all of which results in acquired PS deficiency [ 4 ]. The incidence of PS deficiency in patients undergoing cardiac surgery reportedly ranges from 0.03 to 0.13% [ 5 ].…”

“…No purified form of PS is available for clinical use. FFP is the only agent that can enhance the level of PS [ 4 ]. Hsu and Despotis [ 3 ] described two patients with PS deficiency who underwent CABG, and FFP was transfused as the priming fluid of CPB.…”

“…Hsu and Despotis [ 3 ] described two patients with PS deficiency who underwent CABG, and FFP was transfused as the priming fluid of CPB. Balan [ 4 ] transfused FFP during the pre-bypass period and added more FFP for CPB priming. Neither of these reports focused on transfusing FFP during the period of heparin cessation.…”

“…Second, approximately 60% of PS antigen is bound to C4b-binding protein (C4bBP) [ 1 ]. Acute inflammation triggered by CPB can result in an increase of C4bBP, which may lead to a reduction in free PS antigen by increasing its binding to C4bBP [ 1 , 4 ]. In that case, a low level of free PS antigen does not necessarily indicate a shortage of FFP volume.…”

“…Although fresh frozen plasma (FFP) is rich in PS and is often used in cardiac surgery for patients with PS deficiency [ 3 , 4 ], the most appropriate times and volume of its administration to prevent thromboembolism remain to be clarified.…”