Retrospective report of contraindications to extracorporeal membrane oxygenation (ECMO) among adults with acute respiratory distress syndrome (ARDS)

Severe ARDS Secondary to Legionella Pneumonia Requiring VV ECMO in the Setting of Newly Diagnosed Hairy Cell Leukemia

Venovenous (VV) extracorporeal membrane oxygenation (ECMO) for severe acute respiratory distress syndrome (ARDS) is initiated in patients with high mortality as a potential lifesaving intervention. Hematologic malignancy (HM) is considered a relative exclusion criterion by the Extracorporeal Life Support Organization (ELSO). This case examines the relative contraindication and presents a successful outcome. A healthy 59-year-old male presented with respiratory distress. On arrival his SpO₂ on room air was 82%, chest x-ray revealed a lobar infiltrate, complete blood count demonstrated severe leukopenia, and a peripheral blood smear demonstrated cytoplasmic inclusions concerning for hairy cells. He was intubated and decision was made to initiate VV-ECMO during hospital day (HD) 1. Cytometry later confirmed a diagnosis of hairy cell leukemia (HCL). A diagnosis of Legionella was confirmed on HD 5. Initial hospitalization was complicated by progression to complete bilateral lung involvement, pulmonary hemorrhage, recurrent tachyarrhythmias, hemodynamic instability, and acute renal failure. Respiratory status stabilized and eventually began to improve. On HD 27, he was decannulated and later discharged to rehabilitation. Four months later he received inpatient chemotherapy and is currently in full remission. This is a successful outcome in a patient with severe ARDS requiring VV-ECMO in the setting of newly diagnosed HCL. The 10-year survival for treated HCL is near 100%. Due to favorable prognosis, HCL should not be considered a relative contraindication to VV-ECMO. While HM remains a relative exclusion criterion by the ELSO, it is important to analyze each patient individually and make decisions based on evolving bodies of evidence.

Heparin-Sparing Anticoagulation Strategies Are Viable Options for Patients on Veno-Venous ECMO

BACKGROUND

Extracorporeal membrane oxygenation (ECMO), a rescue therapy for pulmonary failure, has traditionally been limited by anticoagulation requirements. Recent practice has challenged the absolute need for anticoagulation, expanding the role of ECMO to patients with higher bleeding risk. We hypothesize that mortality, bleeding, thrombotic events, and transfusions do not differ between heparin-sparing and full therapeutic anticoagulation strategies in veno-venous (VV) ECMO management.

MATERIALS AND METHODS

Adult VV ECMO patients between October 2011 and May 2018 at a single center were reviewed. A heparin-sparing strategy was implemented in October 2014; we compared outcomes in an as-treated fashion. The primary end point was survival. Secondary end points included bleeding, thrombotic complications, and transfusion requirements.

RESULTS

Forty VV ECMO patients were included: 17 (147 circuit-days) before and 23 (214 circuit-days) after implementation of a heparin-sparing protocol. Patients treated with heparin-sparing anticoagulation had a lower body mass index (28.5 ± 7.1 versus 38.1 ± 12.4, P = 0.01), more often required inotropic support before ECMO (82 versus 50%, P = 0.05), and had a lower mean activated clotting time (167 ± 15 versus 189 ± 15 s, P < 0.01). There were no significant differences in survival to decannulation (59 versus 83%, P = 0.16) or discharge (50 versus 72%, P = 0.20), bleeding (32 versus 33%, P = 1.0), thromboembolic events (18 versus 39%, P = 0.17), or transfusion requirements (median 1.1 versus 0.9 unit per circuit-day, P = 0.48).

CONCLUSIONS

Survival, bleeding, thrombotic complications, and transfusion requirements did not differ between heparin-sparing and full therapeutic heparin strategies for management of VV ECMO. VV ECMO can be a safe option in patients with traditional contraindications to anticoagulation.

Dioscin prevents LPS‑induced acute lung injury through inhibiting the TLR4/MyD88 signaling pathway via upregulation of HSP70

Dioscin, as a type of important natural steroidal saponin, has widespread sources, primarily from the fenugreek plant, which is an important raw material in the production of synthetic steroid hormone drugs. Dioscin has anti‑tumor, anti‑inflammatory, antioxidant and other significant pharmacological effects with high medicinal value. The present work aimed to research the protective effect and underlying mechanisms by which dioscin prevents acute lung injury (ALI). Mice were injected with 5 mg/kg LPS to induce lung injury. Mice were treated with dioscin (20, 40 and 60 mg/kg) following LPS‑induced lung injury. Treatment with dioscin significantly decreased total number of alveolar macrophages, water content of lung and total protein concentration in ALI mice. Dioscin treatment significantly suppressed the ALI‑induced interleukin (IL)‑1B, IL‑6, tumor necrosis factor‑α, nuclear factor (NF)‑κB, myeloperoxidase, interferon‑γ and intercellular adhesion molecule‑1 activities in ALI rats. Following this, the authors identified that dioscin significantly also suppressed cyclooxygenase‑2, heat shock protein 70, Toll‑like receptor 4, MyD88 and NF‑κB protein expression in ALI rats. The results suggested that dioscin prevents LPS‑induced ALI through inhibiting the TLR4/MyD88 signaling pathway via upregulation of HSP70.

The impacts of baseline ventilator parameters on hospital mortality in acute respiratory distress syndrome treated with venovenous extracorporeal membrane oxygenation: a retrospective cohort study

BACKGROUND

Venovenous extracorporeal membrane oxygenation (VV-ECMO) is a valuable life support in acute respiratory distress syndrome (ARDS) in adult patients. However, the success of VV-ECMO is known to be influenced by the baseline settings of mechanical ventilation (MV) before its institution. This study was aimed at identifying the baseline ventilator parameters which were independently associated with hospital mortality in non-trauma patients receiving VV-ECMO for severe ARDS.

METHODS

This retrospective study included 106 non-trauma patients (mean age: 53 years) who received VV-ECMO for ARDS in a single medical center from 2007 to 2016. The indication of VV-ECMO was severe hypoxemia (P_aO₂/ FiO₂ ratio < 70 mmHg) under pressure-controlled MV with peak inspiratory pressure (PIP) > 35 cmH₂O, positive end-expiratory pressure (PEEP) > 5 cmH₂O, and F_iO₂ > 0.8. Important demographic and clinical data before and during VV-ECMO were collected for analysis of hospital mortality.

RESULTS

The causes of ARDS were bacterial pneumonia (n = 41), viral pneumonia (n = 24), aspiration pneumonitis (n = 3), and others (n = 38). The median duration of MV before ECMO institution was 3 days and the overall hospital mortality was 53% (n = 56). The medians of PaO₂/ FiO₂ ratio, PIP, PEEP, and dynamic pulmonary compliance (PC_dyn) at the beginning of MV were 84 mmHg, 32 cmH₂O, 10 cmH₂O, and 21 mL/cmH₂O, respectively. However, before the beginning of VV-ECMO, the medians of PaO₂/ FiO₂ ratio, PIP, PEEP, and PC_dyn became 69 mmHg, 36 cmH₂O, 14 cmH₂O, and 19 mL/cmH₂O, respectively. The escalation of PIP and the declines in PaO₂/ FiO₂ ratio and PC_dyn were significantly correlated with the duration of MV before ECMO institution. Finally, the duration of MV (OR: 1.184, 95% CI: 1.079-1.565, p < 0.001) was found to be the only baseline ventilator parameter that independently affected the hospital mortality in these ECMO-treated patients.

CONCLUSION

Since the duration of MV before ECMO institution was strongly correlated to the outcome of adult respiratory ECMO, medical centers are suggested to find a suitable prognosticating tool to determine the starting point of respiratory ECMO among their candidates with different duration of MV.

TRIAL REGISTRATION

This study reported a health care intervention on human participants and was retrospectively registered. The Chang Gung Medical Foundation Institutional Review Board approved the study (no. 201601483B0 ) on November 23, 2016. All of the data were extracted from December 1, 2016, to January 31, 2017.