Extracorporeal membrane oxygenation in adult patients with hematologic malignancies and severe acute respiratory failure.

INTRODUCTION: Acute respiratory failure (ARF) is the main reason for intensive care unit (ICU) admissions in patients with hematologic malignancies (HMs). We report the first series of adult patients with ARF and HMs treated with extracorporeal membrane oxygenation (ECMO). METHODS: This is a retrospective cohort study of 14 patients with HMs (aggressive non-Hodgkin lymphoma (NHL) n = 5; highly aggressive NHL, that is acute lymphoblastic leukemia or Burkitt lymphoma, n = 5; Hodgkin lymphoma, n = 2; acute myeloid leukemia, n = 1; multiple myeloma, n = 1) receiving ECMO support because of ARF (all data as medians and interquartile ranges; age, 32 years (22 to 51 years); simplified acute physiology score II (SAPS II): 51 (42 to 65)). Etiology of ARF was pneumonia (n = 10), thoracic manifestation of NHL (n = 2), sepsis of nonpulmonary origin (n = 1), and transfusion-related acute lung injury (n = 1). Diagnosis of HM was established during ECMO in four patients, and five first received (immuno-) chemotherapy on ECMO. RESULTS: Before ECMO, the PaO2/FiO2 ratio was 60 (53 to 65), (3.3 to 3.7). Three patients received venoarterial ECMO because of acute circulatory failure in addition to ARF; all other patients received venovenous ECMO. All patients needed vasopressors, and five needed hemofiltration. Thrombocytopenia occurred in all patients (lowest platelet count was 20 (11 to 21) G/L). Five major bleeding events were noted. ECMO duration was 8.5 (4 to 16) days. ICU and hospital survival was 50%. All survivors were alive at follow-up (36 (10 to 58) months); five patients were in complete remission, one in partial remission, and one had relapsed. CONCLUSIONS: ECMO therapy is feasible in selected patients with HMs and ARF and can be associated with long-term disease-free survival.

Low dose acetylsalicylic acid and shedding of microparticles in vivo in humans.

BACKGROUND: Microparticles (MPs) have procoagulant properties as shown in vitro and in animal models. Their role in haemostatic system activation at the site of a vascular injury in vivo in humans has not been studied. MATERIAL AND METHODS: In a prospective randomized crossover study, 13 healthy volunteers were given 100 mg acetylsalicylic acid or placebo daily for 7 days. Number and cellular origin, expression of tissue factor (TF) and phosphatidylserine on MPs, and platelet and coagulation activation markers [beta-thromboglobulin (beta-TG), prothrombin fragment f1.2 (f1.2)] were measured in venous blood and in blood from a vascular injury (shed blood) by flow cytometry and immunoassays, respectively. RESULTS: The number of MPs was significantly higher in shed blood than in venous blood. The majority of MPs were platelet derived. The expression of TF on MPs was low, but higher in shed blood than in venous blood. TF positive MPs were significantly higher in shed blood, which was due to an increase of MPs from platelets (PMPs). In shed blood, the number of TF expressing platelet-derived MPs correlated with beta-TG, but not with f1.2. Low dose acetylsalicylic acid did not affect shedding of PMPs, neither in venous blood nor in shed blood. CONCLUSIONS: The release of PMPs locally at the site of platelet plug formation in humans indicates a possible role of MPs for haemostatic system activation in vivo. Low dose acetylsalicylic acid might not be strong enough to suppress shedding of PMPs in the microcirculation.

Up-regulation of interleukin 33 and soluble ST2 serum levels in liver failure.

BACKGROUND: IL-33, a member of the IL-1 family, induces the production of pro-inflammatory and Th2-associated cytokines and may also serve as an 'alarmin' similar to HMGB1. Soluble ST2 has been implicated as a decoy receptor, to attenuate Th2 inflammatory responses. The relevance of both molecules in hepatic failure is unknown. MATERIALS AND METHODS: The trial was a prospective preliminary study in a university hospital surgical ICU; 11 patients with acute liver failure (ALF) and 12 patients with acute-on-chronic liver failure (ACLF), who were admitted to the ICU; 14 patients with chronic hepatic failure (CHF) awaiting liver transplantation; 13 healthy individuals served as controls. IL-33 and soluble ST2 concentrations were determined by enzyme linked immunosorbent assay (ELISA). RESULTS: The concentration of IL-33 and soluble ST2 was significantly higher in ALF, ACLF, and CHF patients compared with the controls. Soluble ST2 serum concentration was significantly elevated in ALF and ACLF compared with CHF; moreover, soluble ST2 was significantly higher in CHF compared with healthy controls. IL-33 and soluble ST2 serum levels correlated significantly (r = 0.6117, P < 0.0001). Moreover, there was a correlation between IL-33 serum levels and alanine aminotransferase (ALT) activity in CHF, ALF, and ACLF patients (r = 0.4321, P = 0.0171). CONCLUSION: Our data provide evidence for elevated levels of IL-33 and soluble ST2 in liver failure, which could a sign of immune hyperactivation, and/or a mechanism to down-regulate inflammation. Especially, soluble ST2 maybe useful to discern acute from chronic hepatic failure or to monitor the course and the severity of the disease.