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TOPIC: Critical Care TYPE: Fellow Case Reports INTRODUCTION: Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is increasingly used in the management of respiratory failure failing to respond to conventional methods. This case highlights the importance of identifying and rectifying complications of ECMO. CASE PRESENTATION: We present a 56-year-old male who presented after being diagnosed with COVID-19. His past medical history included diabetes mellitus and hypertension. He was admitted to the intensive care unit for rapidly worsening hypoxic respiratory failure requiring mechanical ventilation. Despite trials of paralysis and prone positioning for severe acute respiratory distress syndrome (ARDS), the patient did not improve and was cannulated with a 21 French right internal jugular (IJ) and 25 French right femoral cannulas under fluoroscopic guidance for VV-ECMO.On initiation, flow was suboptimal despite revolutions per minute (RPM) as high as 5000 generating flows of 2.1 liters per minute (LPM). Post oxygenator pressures were 500-520 mmHg. Rectifying this problem was delayed by 12 hours. A new left IJ vein return cannula was placed and the prior return cannula removed which had a kink on its distal end that was not seen on imaging. Flows improved significantly after this change.The return cannula blood was noted to be dark red, which prompted evaluation of membrane lung function which was normal. A co-oximetry demonstrated significantly elevated methemoglobinemia of 15%. Medications were reviewed and none were noted to cause methemoglobinemia. Patient was treated with repeated doses of methylene blue.The patient developed multi-organ failure as well as refractory vasoplegic shock on multiple vasopressors. The family made the decision to transition patient's care to comfort care on day 5 of VV-ECMO. DISCUSSION: This case demonstrates the grave consequences of late identification and correction of flow limitation in VV-ECMO and how a kinked cannula led to severe hemolysis causing methemoglobinemia. In literature, cooxyhemoglobin correlated with increasing hemolysis, however there is indirect evidence that with increased hemolysis, increase oxygen radicals can lead to the formation of methemoglobin. Methemoglobinemia is a known cause of renal failure, as well as multi-organ failure. Monitoring levels of methemoglobin have both diagnostic and therapeutic advantages.This case also highlights a rather atypical cause of dark blood in return cannula, other than membrane lung dysfunction. Methemoglobin in classic teaching causes "chocolate-red" blood, with a low spO2 and a relatively high PaO2, as noted in our patient. CONCLUSIONS: It is important to be well versed with the possible complications of ECMO. Common differential diagnoses for flow limitation include hypovolemia, shock, increased abdominal/thoracic pressures, kinked cannula, thrombus formation or obstructed drainage from the return cannula. REFERENCE #1: Hemolysis in pediatric patients receiving centrifugal-pump extracorporeal membrane oxygenation: prevalence, risk factors, and outcomes. Lou S., MacLaren G., Best D., Delzoppo C., Butt W. Crit Care Med. 2014 May;42(5):1213-20. REFERENCE #2: Methemoglobinemia: A Diagnosis Not to Be Missed. Lata K., Janardhanan., R. AJM ONLINE CLINICAL COMMUNICATION TO THE EDITOR. 2015 Oct;128(10): E45-6. REFERENCE #3: The Complex Relationship of Extracorporeal Membrane Oxygenation and Acute Kidney Injury: Causation or Association? Kilburn D. J., Shekar K., Fraser J. F., Biomed Res Int. 2016 Feb. 2016;2016:1094296. DISCLOSURES: No relevant relationships by Anna Abbasi, source=Web Response No relevant relationships by Cliff Chen, source=Web Response No relevant relationships by Ethan Karle, source=Web Response No relevant relationships by Shyam Shankar, source=Web Response No relevant relationships by Blaine Winterton, source=Web Response
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INTRODUCTION: Aspergillus, a hyaline mold, causes invasive pulmonary aspergillosis (IPA), a severe systemic infection in immunocompromised patients. IPA has a high mortality rate and is a well-documented complication of severe influenza pneumonia. Emerging studies in Europe have identified secondary IPA cases with coronavirus disease 2019 (COVID-19), known as CAPA. With over 72.8 million confirmed cases of patients with COVID-19 infection worldwide as of December 2020, CAPA is a significant complication. Here, we report an immunocompromised female patient with IPA likely due to the adverse effects of COVID-19 therapy. CASE: A 58-year-old Caucasian woman with a history of chronic obstructive pulmonary disease (COPD), type 2 diabetes mellitus, obstructive sleep apnea, and hypertension was admitted for COVID-19 pneumonia with elevated inflammatory markers. She was started on dexamethasone, remdesivir and received convalescent plasma. She was ventilated and pronated. Bronchoscopy on day 5 showed multiple white plaques and a single black plaque of 1 cm diameter on the left bronchial wall. Bronchoalveolar lavage (BAL) fungal stain revealed acute-angled septate hyphae and culture yielded Aspergillus. niger. BAL and serum galactomannan (GM) levels returned elevated at ≥ 3.750 index with a negative serum beta-D glucan assay. A diagnosis of IPA was made, and voriconazole was initiated. Due to refractory hypoxia, extracorporeal membrane oxygenation was started. Her stay was further complicated by a Dieulafoy's lesion, bronchial bleeding, and E. coli pneumonia. On day 31, care was withdrawn, and she passed away. DISCUSSION: IPA is a well-known complication in immunocompromised patients, with known risk factors including COPD, diabetes mellitus, and severe influenza infection. The hypothesized CAPA mechanisms include damaged respiratory epithelium, dysfunctional mucociliary clearance, and local immune paralysis facilitating fungal invasion. COVID-19 pneumonia therapy with experimental use of dexamethasone and tocilizumab may alter local and systemic immunity, increasing IPA's risk. While no diagnostic criteria exist for CAPA, our patient met diagnostic criteria for IPA with her elevated BAL and serum GM levels >3.750 and positive BAL fungal stain with culture. Recommended treatment for IPA is voriconazole, which is superior to amphotericin in reducing mortality. CONCLUSION: Here, we report a rare case of CAPA by A. niger in an immunocompromised patient with severe COVID- 19 pneumonia. Further studies must consider the regular screening of IPA in critically ill patients, determine the performance of serum and BAL GM in COVID-19 patients, and if COVID-19 pneumonia or its treatments are independent risk factors for CAPA.