Limited Effect of Prevention Strategies on Incidence of Clinically Detectable Venous Thromboembolism After Lung Transplantation.

BACKGROUND: Thromboembolic complications are common post-lung transplant, leading to significant morbidity. We instituted multiple interventions because of an observed 36.8% incidence of venous thromboembolism (VTE) (Incidence rate (IR) 5.74/1000 pt days) in our recipients. METHODS: Our initiative commenced January 2015 with enoxaparin initiation within 6-8 hours of intensive care unit arrival and continuation for 4-6 weeks. We evaluated the IR of VTE in lung transplant recipients within 90 days of transplant. In 2017, the protocol was modified to extend the time to initiation of prophylaxis to within 72 hours of ICU arrival. In 2019, we further amended our intraoperative vascular access strategy. RESULTS: Eighteen of 26 lung transplant recipients (LTR) met inclusion criteria in the 2015 cohort. Six of 18 (33.3%) developed VTE, 50% of which were upper extremity (UE), line associated. Fifty two of 75 LTR were eligible for enoxaparin prophylaxis in the 2017 cohort. Fifteen of 52 subjects (28.8%) developed VTE, 77.8% of which were UE and line associated. Despite improved adherence in 2017, there was little change in VTE IR (3.90/1000 pt days compared with 3.85/1000 pt days). Twenty six of 43 LTR met protocol inclusion criteria in the 2019 cohort. Ten subjects (38.5%) developed VTE, 67% of which were UE and line associated (IR 5.18/1000 pt days). CONCLUSION: Our prospective study found that LTR remain at high risk for VTE despite aggressive prophylaxis with 4-6 weeks of enoxaparin and adjustment of vascular access approach. Alternative interventions should be investigated to minimize VTE development in this vulnerable population.

Alemtuzumab as a Therapy for Chronic Lung Allograft Dysfunction in Lung Transplant Recipients With Short Telomeres.

Alemtuzumab, a monoclonal antibody targeting CD52 that causes lymphocyte apoptosis, is a form of advanced immunosuppression that is currently used as a therapy for refractory acute cellular rejection and chronic lung allograft dysfunction in lung transplant recipients (1-3). Side effects of alemtuzumab include bone marrow suppression, infection, and malignancy. Whether alemtuzumab can be safely used in allograft recipients that have an increased propensity for bone marrow suppression due to telomeropathies is unknown. In a retrospective case series, we report outcomes associated with alemtuzumab in three lung allograft recipients with short telomere lengths, comparing endpoints such as leukopenia, transfusion needs, infection, hospitalization and survival to those of 17 patients without known telomeropathies that received alemtuzumab. We show that the use of alemtuzumab in lung transplant recipients with short telomeres is safe, though is associated with an increased incidence of neutropenia, thrombocytopenia and anemia requiring packed red blood cell transfusions. Alemtuzumab appears to be an acceptable advanced immunosuppressive therapy in patients with telomeropathies, though given the design and scope of this study, the actual clinical effect needs further evaluation in larger trials.