Anti-HLA immunization of patients qualified for lung transplantation - Single center study.

For lung transplantation, the presence of donor-specific anti-HLA antibodies (DSA) is an important factor of antibody-mediated rejection (AMR) in its hyperacute, acute or chronic form during long-term follow up. The aim of the study was to assess the allosensitization of Polish patients qualified for a lung transplantation in our center. A retrospective study of 161 potential lung allograft recipients, also of 31 patients transplanted in the University Hospital of Gdansk, between June 2018 and December 2020 were performed. 121 potential recipients were thoroughly tested for immunization status before eventual lung transplantation. SAB-testing, PRA-CDC and vPRA assessment, and HLA typing were performed to guide donor-recipient matching and risk stratification. Then 73 patients were separated and qualified for the list of patients awaiting lung transplantation. Then 31 patients were transplanted based on a negative biological crossmatch result. The patients were generally not sensitized, as the median PRA-CDC was 0% (min 0; max 53), and the vPRA, calculated according to HLA ABDR (>2000 cut-off MFI), was 8% (min 0; max 99). If the cut-off was split into 2000 MFI for HLA ABDR, 10,000 MFI for HLAC, and 7000 MFI for HLA-DQ, the vPRA increased to 20% (min 0; max 99). The immunization status was assessed with single antigen-SAB assays. For class I, the number of any detectable alloantibodies was 14 (11.6%) 21 (17.35%) 16 (13.22%) for locus HLA-A/B/C, and 28 (23.14%) 30 (24.8%) 24 (19.8%) for locus HLA-DR/DQ/DP, respectively. The immunization of the transplanted patients was then analyzed in detail. Summarizing, the study is an analysis of the degree of anti-HLA immunization in the population of patients eligible for lung transplantation, which showed that this degree is of low intensity and can be effectively and safely and very precisely diagnosed before transplantation.

Filter life span in postoperative cardiovascular surgery patients requiring continuous renal replacement therapy, using a postdilution regional citrate anticoagulation continuous hemofiltration circuit.

BACKGROUND: Regional citrate anticoagulation (RCA) is the recommended standard for continuous renal replacement therapy (CRRT). This study assesses its efficacy in patients admitted to critical care following cardiovascular surgery and the influence of standard antithrombotic agents routinely used in this specific group. METHODS: Consecutive cardiovascular surgery patients treated with postdilution hemofiltration with RCA were included in this prospective observational study. The primary outcome of the study was CRRT circuit life-span adjusted for reasons other than clotting. The secondary outcome evaluated the influence of standard antithrombotic agents (acetylsalicylic acid [ASA], low molecular weight heparin [LMWH] or fondaparinux as thromboprophylaxis or treatment dose with or without ASA) on filter life. RESULTS: Fifty-two patients underwent 193 sessions of continous veno-venous hemofiltration, after exclusion of 15 sessions where unfractionated heparin was administered. The median filter life span was 58 hours. Filter life span was significantly longer in patients receiving therapeutic dose of LMWH or fondaparinux (79 h [2-110]), in comparison to patients treated with prophylactic dose of LMWH or fondaparinux (51 h [7-117], p < 0.001), and patients without antithrombotic prophylaxis (42 h [2-91], p < 0.0001). 12 bleeding episodes were observed; 8 occurred in patients receiving treatment dose anticoagulation, 3 in patients receiving prophylactic dose anticoagulation and 1 in a patient with no antithrombotic prophylaxis. CONCLUSIONS: A postdilution hemofiltration with RCA provides prolonged filter life span when adjusted for reasons other than clotting. Patients receiving treatment dose anticoagulation had a significantly longer filter life span than those who were on prophylactic doses or ASA alone.

Ionic homeostasis, acid-base balance and the risk of citrate accumulation in patients after cardiovascular surgery treated with continuous veno-venous haemofiltration with post-dilution regional citrate anticoagulation - An observational case-control study.

BACKGROUND: Patients after cardiovascular surgery, requiring renal replacement therapy, can benefit from adequate non-heparin circuit anticoagulation. Simplified regional citrate anticoagulation (RCA) protocol proposes the use of citric acid dextrose formula A (ACD-A) during post-dilutional continuous veno-venous hemofiltration (CVVH) with standard bicarbonate buffered calcium containing replacement solution. Citrate accumulation diagnosed upon total to ionized calcium ratio (tCa/iCa) and low ionized calcium (iCa) are considered as the biggest risks related to regional citrate accumulation. METHODS: This prospective observational case-control study evaluated electrolyte and acid-base homeostasis in cardiovascular surgery patients treated with post-dilution CVVH with a simplified RCA protocol with ACD-A. In total, 50 consecutive cardiovascular surgery patients were evaluated. Base excess, pH, bicarbonate, lactate, Na+, Cl-, Mg++, and inorganic phosphate concentrations, the total to ionized calcium ratio (tCa/iCa), and high anion gap metabolic acidosis were assessed during haemofiltration treatment in survivors and non-survivors. RESULTS: Thirty-three (66%) patients died. The therapies were very well balanced in sodium and chloride homeostasis. The lactate concentration and anion gap decreased during CVVH sessions lasting longer than 72 hours, but no inter-group difference was observed. The tCa/iCa ratio exceeded 4.5% and was significantly higher in non-survivors (p=0.037). Initial lactate concentration did not correlate with tCa/iCa ratio during haemofiltration. Magnesium and phosphate concentrations decreased and additional supplementation with magnesium was necessary. The magnesium concentration was lower in the non-survivors. CONCLUSIONS: The incidence of citrate accumulation exceeded 4% and was significantly higher in non-survivors. Supplementation with magnesium and phosphate ions is needed in CVVH with RCA.