SARS-CoV-2 pneumonia-receptor binding and lung immunopathology: a narrative review.

The current pandemic of COVID-19 caused thousands of deaths and healthcare professionals struggle to properly manage infected patients. This review summarizes information about SARS-CoV-2 receptor binding dynamics and intricacies, lung autopsy findings, immune response patterns, evidence-based explanations for the immune response, and COVID-19-associated hypercoagulability.

Acute cholangitis in intensive care units: clinical, biological, microbiological spectrum and risk factors for mortality: a multicenter study.

BACKGROUND: Little is known on the outcome and risk factors for mortality of patients admitted in Intensive Care units (ICUs) for Acute cholangitis (AC). METHODS: Retrospective multicenter study included adults admitted in eleven intensive care units for a proven AC from 2005 to 2018. Risk factors for in-hospital mortality were identified using multivariate analysis. RESULTS: Overall, 382 patients were included, in-hospital mortality was 29%. SOFA score at admission was 8 [5-11]. Biliary obstruction was mainly related to gallstone (53%) and cancer (22%). Median total bilirubin and PCT were respectively 83 µmol/L [50-147] and 19.1 µg/L [5.3-54.8]. Sixty-three percent of patients (n = 252) had positive blood culture, mainly Gram-negative bacilli (86%) and 14% produced extended spectrum beta lactamase bacteria. At ICU admission, persisting obstruction was frequent (79%) and biliary decompression was performed using therapeutic endoscopic retrograde cholangiopancreatography (76%) and percutaneous transhepatic biliary drainage (21%). Adjusted mortality significantly decreased overtime, adjusted OR for mortality per year was 0.72 [0.54-0.96] (p = 0.02). In a multivariate analysis, factors at admission associated with in-hospital mortality were: SOFA score (OR 1.14 [95% CI 1.05-1.24] by point, p = 0.001), lactate (OR 1.21 [95% CI 1.08-1.36], by 1 mmol/L, p < 0.001), total serum bilirubin (OR 1.26 [95% CI 1.12-1.41], by 50 µmol/L, p < 0.001), obstruction non-related to gallstones (p < 0.05) and AC complications (OR 2.74 [95% CI 1.45-5.17], p = 0.002). Time between ICU admission and biliary decompression > 48 h was associated with in-hospital mortality (adjusted OR 2.73 [95% CI 1.30-6.22], p = 0.02). CONCLUSIONS: In this large retrospective multicenter study, we found that AC-associated mortality significantly decreased overtime. Severity of organ failure, cause of obstruction and local complications of AC are risk factors for mortality, as well as delayed biliary drainage > 48 h.

Post-transfusion platelet responses in critically ill cancer patients with hypoproliferative thrombocytopenia.

BACKGROUND: Platelet transfusion is aimed at increasing platelet counts to prevent or treat bleeding. Critically ill cancer patients with hypoproliferative thrombocytopenia are high consumers of blood products. We herein described their post-transfusion platelet responses in the intensive care unit (ICU) and analyzed the determinants of poor post-transfusion increments. STUDY DESIGN AND METHODS: This was a single-center 9-year (2009-2017) retrospective observational study. Patients with malignancies and presumed or proven hypoproliferative thrombocytopenia who had received at least one platelet transfusion in the ICU were included. Poor post-transfusion platelet increments were defined as body surface-adjusted corrected count increment (CCI) <7, or alternatively as weight-adjusted platelet transfusion recovery (PTR) <0.2. Patients were deemed refractory to platelet transfusions when two consecutive ABO-compatible transfusions resulted in poor platelet increments. RESULTS: A total of 1470 platelet transfusions received by 326 patients were analyzed. Indications for platelet transfusions were distributed into prophylactic (44.5%), peri-procedural (18.1%) and therapeutic (37.4%). Regardless of indications, 54.6% and 55.4% of transfusion episodes were associated with a CCI <7 or a PTR <0.2. Factors independently associated with poor post-transfusion increments were lower body mass index, spleen enlargement, concurrent severity of clinical condition, fever ≥39°C, antibiotic therapy and increased storage duration of platelet concentrates. Eventually, 48 patients developed refractoriness to platelet transfusion, which was associated increased incidence of bleeding events. CONCLUSION: Platelet transfusions are often associated with poor increments in critically ill cancer patients with hypoproliferative thrombocytopenia. The findings suggest amenable interventions to improve the platelet transfusion practices in this setting.

Subcostal transversus abdominis plane block for postoperative analgesia in liver transplant recipients: a before-and-after study.

INTRODUCTION: Postoperative pain management after orthotopic liver transplantation is complex due to impaired liver function and frequent acute kidney dysfunction. Subcostal transversus abdominis plane (TAP) block may be of interest in this population. The aim of this study was to evaluate the impact of subcostal TAP block on opioid consumption after liver transplantation. METHODS: We conducted a before-and-after single center study. During the first period, we included patients whom did not receive an analgesic TAP block. During the second period, we included those with bilateral ultrasound-guided subcostal TAP block (20 mL ropivacaïne 0.2% each side). Patients requiring sedation within 48 hours of surgery as well as patients with combined liver and kidney transplants or skin-only closures were excluded. The primary outcome was cumulative oral morphine consumption within 48 hours after surgery. Secondary outcomes included pain scores and TAP block-related complications. RESULTS: A total of 132 patients were included in the non-TAP block group and 78 patients in the TAP block group. The median oral morphine equivalent consumption (IQR) within 48 hours following surgery was 74 mg (39; 112) for the non-TAP block group and 50 mg (20; 80) for the TAP block group (p<0.001). There was no difference in pain scores between the two groups. No complications related to the TAP block were reported. CONCLUSION: Subcostal TAP block appears to have a small opioid reducing effect after orthotopic liver transplantation surgery.

Epinephrine restores platelet functions inhibited by ticagrelor: A mechanistic approach.

Ticagrelor, an antagonist of the platelet adenosine diphosphate (ADP)-P2Y12 receptor is recommended for patients with acute coronary syndromes. However, ticagrelor exposes to a risk of bleeding, the management of which is challenging because platelet transfusion is ineffective, and no antidote is yet available. We hypothesized that the vasopressor drug epinephrine could counter the antiplatelet effects of ticagrelor and restore platelet functions. We assessed in vitro the efficiency of epinephrine in restoring platelet aggregation inhibited by ticagrelor and investigated the underlying mechanisms. Washed platelet aggregation and secretion were measured upon stimulation by epinephrine alone or in combination with ADP, in the presence or absence of ticagrelor. Mechanistic investigations used P2Y1 and phosphoinositide 3-kinase (PI3K) inhibitors and included vasodilator-stimulated phosphoprotein (VASP) and Akt phosphorylation assays as well as measurement of Ca2+ mobilisation. We found that epinephrine restored ADP-induced platelet aggregation, but not dense granule release. Epinephrine alone failed to induce aggregation whereas it fully induced VASP dephosphorylation and Akt phosphorylation regardless of the presence of ticagrelor. In the presence of ticagrelor, blockage of the P2Y1 receptor prevented restoration of platelet aggregation by the combination of epinephrine and ADP, as well as intracellular Ca2+ mobilisation. In combination with ADP, epinephrine induced platelet aggregation of ticagrelor-treated platelets through inhibition of the cAMP pathway and activation of the PI3K pathway, thus enabling the P2Y1 receptor signalling and subsequent Ca2+ mobilisation. This proof-of-concept study needs to be challenged in vivo for the management of bleeding in ticagrelor-treated patients.

Extracorporeal membrane oxygenation for severe acute respiratory distress syndrome associated with COVID-19: a retrospective cohort study.

BACKGROUND: Patients with COVID-19 who develop severe acute respiratory distress syndrome (ARDS) can have symptoms that rapidly evolve to profound hypoxaemia and death. The efficacy of extracorporeal membrane oxygenation (ECMO) for patients with severe ARDS in the context of COVID-19 is unclear. We aimed to establish the clinical characteristics and outcomes of patients with respiratory failure and COVID-19 treated with ECMO. METHODS: This retrospective cohort study was done in the Paris-Sorbonne University Hospital Network, comprising five intensive care units (ICUs) and included patients who received ECMO for COVID-19 associated ARDS. Patient demographics and daily pre-ECMO and on-ECMO data and outcomes were collected. Possible outcomes over time were categorised into four different states (states 1-4): on ECMO, in the ICU and weaned off ECMO, alive and out of ICU, or death. Daily probabilities of occupation in each state and of transitions between these states until day 90 post-ECMO onset were estimated with use of a multi-state Cox model stratified for each possible transition. Follow-up was right-censored on July 10, 2020. FINDINGS: From March 8 to May 2, 2020, 492 patients with COVID-19 were treated in our ICUs. Complete day-60 follow-up was available for 83 patients (median age 49 [IQR 41-56] years and 61 [73%] men) who received ECMO. Pre-ECMO, 78 (94%) patients had been prone-positioned; their median driving pressure was 18 (IQR 16-21) cm H2O and PaO2/FiO2 was 60 (54-68) mm Hg. At 60 days post-ECMO initiation, the estimated probabilities of occupation in each state were 6% (95% CI 3-14) for state 1, 18% (11-28) for state 2, 45% (35-56) for state 3, and 31% (22-42) for state 4. 35 (42%) patients had major bleeding and four (5%) had a haemorrhagic stroke. 30 patients died. INTERPRETATION: The estimated 60-day survival of ECMO-rescued patients with COVID-19 was similar to that of studies published in the past 2 years on ECMO for severe ARDS. If another COVID-19 outbreak occurs, ECMO should be considered for patients developing refractory respiratory failure despite optimised care. FUNDING: None.