ABSTRACT
The intrinsic and extrinsic activation pathways of the hemostatic system converge when prothrombin is converted to thrombin. The ability to generate an adequate thrombin burst is the most central aspect of the coagulation cascade. The thrombin-generating potential in patients following cardiopulmonary bypass (CPB) may be indicative of their hemostatic status. In this report, thrombography, a unique technique for directly measuring the potential of patients' blood samples to generate adequate thrombin bursts, is used to characterize the coagulopathic profile in post-CPB patients. Post-CPB hemostasis is typically achieved with protamine reversal of heparin anticoagulation and occasionally supplemented with blood product component transfusions. In this pilot study, platelet poor plasma samples were derived from 11 primary cardiac surgery patients at five time points: prior to CPB, immediately post-protamine, upon arrival to the intensive care unit (ICU), 3 hours post-ICU admission, and 24 hours after ICU arrival. Thrombography revealed that the Endogenous Thrombin Potential (ETP) was not different between [Baseline] and [PostProtamine] but proceeded to deteriorate in the immediate postoperative period. At the [3HourPostICU] time point, the ETP was significantly lower than the [Baseline] values, 1233 +/- 591 versus 595 +/- 379 nM.min (mean +/- SD; n=9, p < .005), despite continued adequacy of hemostasis. ETPs returned to baseline values the day after surgery. Transfusions received, conventional blood coagulation testing results, and blood loss volumes are also presented. Despite adequate hemostasis, thrombography reveals an underlying coagulopathic process that could put some cardiac surgical patients at risk for postoperative bleeding. Thrombography is a novel technique that could be developed into a useful tool for perfusionists and physicians to identify coagulopathies and optimize blood management following CPB.
Subject(s)
Blood Coagulation Disorders/blood , Blood Coagulation Tests/methods , Cardiopulmonary Bypass/adverse effects , Thrombin/biosynthesis , Aged , Aged, 80 and over , Cohort Studies , Female , Hemostasis , Humans , Male , Middle AgedSubject(s)
Myocardial Infarction/etiology , Thrombocythemia, Essential/complications , Thrombosis/etiology , Adolescent , Female , Humans , Hydroxyurea/therapeutic use , Nucleic Acid Synthesis Inhibitors/therapeutic use , Platelet Count , Thrombocythemia, Essential/drug therapy , Thrombosis/pathologyABSTRACT
We report on the feasibility, safety, and efficacy of performing therapeutic plasmapheresis (TPE) in parallel with extracorporeal membrane oxygenation (ECMO) to alleviate antibody mediated rejection (AMR) after heart transplantation. Two pediatric and one adult patient presented with severe congestive heart failure and respiratory distress after heart transplantation and required ECMO support. TPE was initiated to treat AMR while patients remained on ECMO. Each patient received three to five procedures either every day or every other day. One equivalent total plasma volume (TPV) was processed for each procedure (patient TPV + ECMO extracorporeal TPV). A total of 13 TPE procedures were performed with 12 procedures completed without complications or adverse events; one procedure was terminated before completion because of cardiac arrhythmia. Anti-HLA antibody titers decreased after TPE in all three patients. Ventricular function improved and ECMO was discontinued in 2 of 3 patients. Performing large volume TPE with a processed volume up to 2.5 times the patient's TPV is well tolerated in both pediatric (< or = 10 kg) and adult patients. TPE in parallel with ECMO is feasible, safe, and may be measurably effective at reducing anti-HLA antibodies and should be considered as part of the treatment for patients with early AMR after heart transplantation.
