Effects of extracorporeal CO2 removal on gas exchange and ventilator settings: a systematic review and meta-analysis.

PURPOSE: A systematic review and meta-analysis to evaluate the impact of extracorporeal carbon dioxide removal (ECCO2R) on gas exchange and respiratory settings in critically ill adults with respiratory failure. METHODS: We conducted a comprehensive database search, including observational studies and randomized controlled trials (RCTs) from January 2000 to March 2022, targeting adult ICU patients undergoing ECCO2R. Primary outcomes were changes in gas exchange and ventilator settings 24 h after ECCO2R initiation, estimated as mean of differences, or proportions for adverse events (AEs); with subgroup analyses for disease indication and technology. Across RCTs, we assessed mortality, length of stay, ventilation days, and AEs as mean differences or odds ratios. RESULTS: A total of 49 studies encompassing 1672 patients were included. ECCO2R was associated with a significant decrease in PaCO2, plateau pressure, and tidal volume and an increase in pH across all patient groups, at an overall 19% adverse event rate. In ARDS and lung transplant patients, the PaO2/FiO2 ratio increased significantly while ventilator settings were variable. "Higher extraction" systems reduced PaCO2 and respiratory rate more efficiently. The three available RCTs did not demonstrate an effect on mortality, but a significantly longer ICU and hospital stay associated with ECCO2R. CONCLUSIONS: ECCO2R effectively reduces PaCO2 and acidosis allowing for less invasive ventilation. "Higher extraction" systems may be more efficient to achieve this goal. However, as RCTs have not shown a mortality benefit but increase AEs, ECCO2R's effects on clinical outcome remain unclear. Future studies should target patient groups that may benefit from ECCO2R. PROSPERO Registration No: CRD 42020154110 (on January 24, 2021).

Fluid management for sepsis-induced hypotension in patients with advanced chronic kidney disease: a secondary analysis of the CLOVERS trial.

BACKGROUND: Early fluid management in patients with advanced chronic kidney disease (CKD) and sepsis-induced hypotension is challenging with limited evidence to support treatment recommendations. We aimed to compare an early restrictive versus liberal fluid management for sepsis-induced hypotension in patients with advanced CKD. METHODS: This post-hoc analysis included patients with advanced CKD (eGFR of less than 30 mL/min/1.73 m2 or history of end-stage renal disease on chronic dialysis) from the crystalloid liberal or vasopressor early resuscitation in sepsis (CLOVERS) trial. The primary endpoint was death from any cause before discharge home by day 90. RESULTS: Of 1563 participants enrolled in the CLOVERS trial, 196 participants had advanced CKD (45% on chronic dialysis), with 92 participants randomly assigned to the restrictive treatment group and 104 assigned to the liberal fluid group. Death from any cause before discharge home by day 90 occurred significantly less often in the restrictive fluid group compared with the liberal fluid group (20 [21.7%] vs. 41 [39.4%], HR 0.5, 95% CI 0.29-0.85). Participants in the restrictive fluid group had more vasopressor-free days (19.7 ± 10.4 days vs. 15.4 ± 12.6 days; mean difference 4.3 days, 95% CI, 1.0-7.5) and ventilator-free days by day 28 (21.0 ± 11.8 vs. 16.5 ± 13.6 days; mean difference 4.5 days, 95% CI, 0.9-8.1). CONCLUSIONS: In patients with advanced CKD and sepsis-induced hypotension, an early restrictive fluid strategy, prioritizing vasopressor use, was associated with a lower risk of death from any cause before discharge home by day 90 as compared with an early liberal fluid strategy. TRIAL REGISTRATION: NCT03434028 (2018-02-09), BioLINCC 14149.

Subjective and objective survival prediction in mechanically ventilated critically ill patients: a prospective cohort study.

BACKGROUND: ICU risk assessment tools, routinely used for predicting population outcomes, are not recommended for evaluating individual risk. The state of health of single patients is mostly subjectively assessed to inform relatives and presumably to decide on treatment decisions. However, little is known how subjective and objective survival estimates compare. METHODS: We performed a prospective cohort study in mechanically ventilated critically ill patients across five European centres, assessed 62 objective markers and asked the clinical staff to subjectively estimate the probability of surviving 28 days. RESULTS: Within the 961 included patients, we identified 27 single objective predictors for 28-day survival (73.8%) and pooled them into predictive groups. While patient characteristics and treatment models performed poorly, the disease and biomarker models had a moderate discriminative performance for predicting 28-day survival, which improved for predicting 1-year survival. Subjective estimates of nurses (c-statistic [95% CI] 0.74 [0.70-0.78]), junior physicians (0.78 [0.74-0.81]) and attending physicians (0.75 [0.72-0.79]) discriminated survivors from non-survivors at least as good as the combination of all objective predictors (c-statistic: 0.67-0.72). Unexpectedly, subjective estimates were insufficiently calibrated, overestimating death in high-risk patients by about 20% in absolute terms. Combining subjective and objective measures refined discrimination and reduced the overestimation of death. CONCLUSIONS: Subjective survival estimates are simple, cheap and similarly discriminative as objective models; however, they overestimate death risking that live-saving therapies are withheld. Therefore, subjective survival estimates of individual patients should be compared with objective tools and interpreted with caution if not agreeing. Trial registration ISRCTN ISRCTN59376582 , retrospectively registered October 31st 2013.

Add-On Prostaglandin E1 in Venovenous Extracorporeal Membrane Oxygenation: A Randomized, Double-Blind, Placebo-controlled Pilot Trial.

Rationale: Prostaglandin E1 (alprostadil; PGE1), in addition to low-dose unfractionated heparin, increases the biocompatibility of extracorporeal systems and enhances the efficacy of artificial organs without increasing bleeding risk. Objectives: We investigated the safety and efficacy of PGE1 in adults receiving venovenous extracorporeal membrane oxygenation (ECMO). Methods: This study was a randomized, double-blind, placebo-controlled phase II pilot trial at two medical intensive care units at the Medical University of Vienna, Austria. Adults with venovenous ECMO were randomly assigned to receive an intravenous infusion of 5 ng/kg/min PGE1 or placebo (0.9% saline) in addition to standard anticoagulation with unfractionated heparin. Measurements and Main Results: The primary outcome was the rate of transfused packed red blood cells per ECMO day. Secondary outcomes were the incidence of and time to clinically overt bleeding and thromboembolic events. A post hoc subgroup analysis included only patients with coronavirus disease (COVID-19). Between September 2016 and April 2021, of 133 screened patients, 50 patients were randomized, of whom 48 received the assigned study medication (24 per group). The transfusion rate was similar between groups (0.41 vs. 0.39; P = 0.733). PGE1 was associated with fewer thromboembolic events (7 vs. 16; P = 0.020) and longer thromboembolism-free time (hazard ratio [HR], 0.302; P = 0.01), fewer clinically overt bleeding events (2 vs. 11; P = 0.017), and longer bleeding-free time (HR, 0.213; P = 0.047). In patients with COVID-19 (n = 25), the HRs for clinically overt bleeding and thromboembolism were 0.276 (95% confidence interval, 0.035-2.186) and 0.521 (95% confidence interval, 0.149-1.825), respectively. Conclusions: Add-on treatment with PGE1 was safe but did not meet the primary endpoint of reducing the rate of red blood cell transfusions in patients receiving venovenous ECMO. Larger studies need to evaluate the safety and efficacy of additional PGE1 in ECMO. Clinical trial registered with EudraCT (2015-005014-30) and www.clinicaltrials.gov (NCT02895373).

Clinical relevance of lung transplantation for COVID-19 ARDS: a nationwide study.

BACKGROUND: Although the number of lung transplantations (LTx) performed worldwide for COVID-19 induced acute respiratory distress syndrome (ARDS) is still low, there is general agreement that this treatment can save a subgroup of most severly ill patients with irreversible lung damage. However, the true proportion of patients eligible for LTx, the overall outcome and the impact of LTx to the pandemic are unknown. METHODS: A retrospective analysis was performed using a nationwide registry of hospitalised patients with confirmed severe acute respiratory syndrome coronavirus type 2 (SARS-Cov-2) infection admitted between January 1, 2020 and May 30, 2021 in Austria. Patients referred to one of the two Austrian LTx centers were analyzed and grouped into patients accepted and rejected for LTx. Detailed outcome analysis was performed for all patients who received a LTx for post-COVID-19 ARDS and compared to patients who underwent LTx for other indications. RESULTS: Between January 1, 2020 and May 30, 2021, 39.485 patients were hospitalised for COVID-19 in Austria. 2323 required mechanical ventilation, 183 received extra-corporeal membrane oxygenation (ECMO) support. 106 patients with severe COVID-19 ARDS were referred for LTx. Of these, 19 (18%) underwent LTx. 30-day mortality after LTx was 0% for COVID-19 ARDS transplant recipients. With a median follow-up of 134 (47-450) days, 14/19 patients are alive. CONCLUSIONS: Early referral of ECMO patients to a LTx center is pivotal in order to select patients eligible for LTx. Transplantation offers excellent midterm outcomes and should be incorporated in the treatment algorithm of post-COVID-19 ARDS.

Prevalence and Clinical Impact of Reduced Coagulation Factor XII Activity in Patients Receiving Extracorporeal Membrane Oxygenation.

OBJECTIVES: Extracorporeal membrane oxygenation provides large surface exposure to human blood leading to coagulation activation. Only limited clinical data are available on contact activation and coagulation factor XII activity in extracorporeal membrane oxygenation patients. DESIGN: Prospective cohort study. SETTING: Three medical ICUs at the Medical University of Vienna. PATIENTS: Adult patients receiving venovenous or venoarterial extracorporeal membrane oxygenation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the change in coagulation factor XII activity in response to extracorporeal membrane oxygenation. Secondary outcomes included the prevalence of reduced coagulation factor XII activity (< 60%) among patients receiving extracorporeal membrane oxygenation and association of coagulation factor XII activity with thromboembolic and bleeding complications. An exploratory endpoint was the association of coagulation factor XII activity and activated partial thromboplastin time in heparinase-treated samples in vitro. Fifty-one patients with a total of 117 samples were included in the study between July 2018 and February 2020. Fifty patients (98%) had reduced coagulation factor XII activity at any timepoint during extracorporeal membrane oxygenation. Median coagulation factor XII activity during extracorporeal membrane oxygenation treatment was 30% (interquartile range, 21.5-41%) and increased after discontinuation (p = 0.047). Patients with thromboembolic complications had higher median coagulation factor XII activity during extracorporeal membrane oxygenation (34% vs 23%; p = 0.023). The odds of a thromboembolic event increased by 200% per tertile of median coagulation factor XII activity (crude odds ratio, 3.034; 95% CI, 1.21-7.63). No association with bleeding was observed. In heparinase-treated samples, coagulation factor XII activity correlated well with activated partial thromboplastin time (r = -0.789; p = 0.007). CONCLUSIONS: We observed a high prevalence of reduced coagulation factor XII activity in adult patients on extracorporeal membrane oxygenation, which may confound activated partial thromboplastin time measurements and limit its clinical usefulness for monitoring and titrating anticoagulation with unfractionated heparin. Lower coagulation factor XII activity was associated with less thromboembolic complications, which may highlight the potential of coagulation factor XII to serve as a target for anticoagulation in extracorporeal membrane oxygenation.

Penetration of echinocandins into wound secretion of critically ill patients.

PURPOSE: Wound infections caused by Candida are life-threatening and difficult to treat. Echinocandins are highly effective against Candida species and recommended for treatment of invasive candidiasis. As penetration of echinocandins into wounds is largely unknown, we measured the concentrations of the echinocandins anidulafungin (AFG), micafungin (MFG), and caspofungin (CAS) in wound secretion (WS) and in plasma of critically ill patients. METHODS: We included critically ill adults with an indwelling wound drainage or undergoing vacuum-assisted closure therapy, who were treated with an echinocandin for suspected or proven invasive fungal infection. Concentrations were measured by liquid chromatography with UV (AFG and MFG) or tandem mass spectrometry detection (CAS). RESULTS: Twenty-one patients were enrolled. From eight patients, serial WS samples and simultaneous plasma samples were obtained within a dosage interval. AFG concentrations in WS amounted to < 0.025-2.25 mg/L, MFG concentrations were 0.025-2.53 mg/L, and CAS achieved concentrations of 0.18-4.04 mg/L. Concentrations in WS were significantly lower than the simultaneous plasma concentrations and below the MIC values of some relevant pathogens. CONCLUSION: Echinocandin penetration into WS displays a high inter-individual variability. In WS of some of the patients, concentrations may be sub-therapeutic. However, the relevance of sub-therapeutic concentrations is unknown as no correlation has been established between concentration data and clinical outcome. Nevertheless, in the absence of clinical outcome studies, our data do not support the use of echinocandins at standard doses for the treatment of fungal wound infections, but underline the pivotal role of surgical debridement.

Distinct pattern of microsusceptibility changes on brain magnetic resonance imaging (MRI) in critically ill patients on mechanical ventilation/oxygenation.

PURPOSE: Over the years, interesting SWI abnormalities in patients from intensive care units (ICU) were observed, not attributable to a specific cause and with uncertain clinical significance. Recently, multiple SWI-hypointense foci were mentioned related to neurological complications of SARS-COV-2 infection. The purpose of the study was to describe the patterns of susceptibility brain changes in critically-ill patients who underwent mechanical ventilation and/or extracorporeal membrane oxygenation (ECMO). METHODS: An institutional board-approved, retrospective study was conducted on 250 ICU patients in whom brain MRI was performed between January 2011 and May 2020. Out of 48 patients who underwent mechanical ventilation/ECMO, in fifteen patients (median age 47.7 years), the presence of SWI abnormalities was observed and described. RESULTS: Microsusceptibilities were located in white-gray matter interface, in subcortical white matter (U-fibers), and surrounding subcortical nuclei in 13/14 (92,8%) patients. In 8/14 (57,1%) patients, SWI foci were seen infratentorially. The corpus callosum was affected in ten (71,4%), internal capsule in five (35,7%), and midbrain/pons in six (42,8%) patients. CONCLUSION: We showed distinct patterns of diffuse brain SWI susceptibilities in critically-ill patients who underwent mechanical ventilation/ECMO. The etiology of these foci remains uncertain, but the association with mechanical ventilation, prolonged respiratory failure, and hypoxemia seems probable explanations.

A bi-centric experience of extracorporeal carbon dioxide removal (ECCO2 R) for acute hypercapnic respiratory failure following allogeneic hematopoietic stem cell transplantation.

Acute respiratory failure (ARF) is the main reason for ICU admission following allogeneic hematopoietic stem cell transplantation (HSCT). Extracorporeal CO2 removal (ECCO2 R) can be used as an adjunct to mechanical ventilation in patients with severe hypercapnia but has not been assessed in HSCT recipients. Retrospective analysis of all allogeneic HSCT recipients ≥18 years treated with ECCO2 R at two HSCT centers. 11 patients (m:f = 4:7, median age: 45 [IQR: 32-58] years) were analyzed. Acute leukemia was the underlying hematologic malignancy in all patients. The time from HSCT to ICU admission was 37 [8-79] months, and 9/11 (82%) suffered from chronic graft-versus-host disease (GVHD) with lung involvement. Pneumonia was the most frequent reason for ventilatory decompensation (n = 9). ECCO2 R was initiated for severe hypercapnia (Pa CO2 : 96 [84-115] mm Hg; pH: 7.13 [7.09-7.27]) despite aggressive mechanical ventilation (invasive, n = 9; non-invasive, n = 2). ECCO2 R effectively resolved blood gas disturbances in all patients, but only 2/11 (18%) could be weaned off ventilatory support, and one (9%) patient survived hospital discharge. Progressive respiratory and multiorgan dysfunction were the main reasons for treatment failure. ECCO2 R was technically feasible but resulted in a low survival rate in our cohort. A better understanding of the prognosis of ARF in patients with chronic GVHD and lung involvement is necessary before its use can be reconsidered in this setting.

International variation in the management of severe COVID-19 patients.

BACKGROUND: There is little evidence to support the management of severe COVID-19 patients. METHODS: To document this variation in practices, we performed an online survey (April 30-May 25, 2020) on behalf of the European Society of Intensive Care Medicine (ESICM). A case vignette was sent to ESICM members. Questions investigated practices for a previously healthy 39-year-old patient presenting with severe hypoxemia from COVID-19 infection. RESULTS: A total of 1132 ICU specialists (response rate 20%) from 85 countries (12 regions) responded to the survey. The survey provides information on the heterogeneity in patient's management, more particularly regarding the timing of ICU admission, the first line oxygenation strategy, optimization of management, and ventilatory settings in case of refractory hypoxemia. Practices related to antibacterial, antiviral, and anti-inflammatory therapies are also investigated. CONCLUSIONS: There are important practice variations in the management of severe COVID-19 patients, including differences at regional and individual levels. Large outcome studies based on multinational registries are warranted.

Efficacy, immunogenicity, and safety of IC43 recombinant Pseudomonas aeruginosa vaccine in mechanically ventilated intensive care patients-a randomized clinical trial.

BACKGROUND: Pseudomonas aeruginosa infections are a serious threat in intensive care units (ICUs). The aim of this confirmatory, randomized, multicenter, placebo-controlled, double-blind, phase 2/3 study was to assess the efficacy, immunogenicity, and safety of IC43 recombinant Pseudomonas aeruginosa vaccine in non-surgical ICU patients. METHODS: Eight hundred patients aged 18 to 80 years admitted to the ICU with expected need for mechanical ventilation for ≥ 48 h were randomized 1:1 to either IC43 100 µg or saline placebo, given in two vaccinations 7 days apart. The primary efficacy endpoint was all-cause mortality in patients 28 days after the first vaccination. Immunogenicity and safety were also evaluated. FINDINGS: All-cause mortality rates at day 28 were 29.2% vs 27.7% in the IC43 and placebo groups, respectively (P = .67). Overall survival (Kaplan-Meier survival estimates, P = .46) and proportion of patients with ≥ one confirmed P. aeruginosa invasive infection or respiratory tract infection also did not differ significantly between both groups. The geometric mean fold increase in OprF/I titers was 1.5 after the first vaccination, 20 at day 28, after the second vaccination, and 2.9 at day 180. Significantly more patients in the placebo group (96.5%) had ≥ one adverse event (AE) versus the IC43 100 µg group (93.1%) (P = .04). The most frequently reported severe AEs in the IC43 and placebo groups were respiratory failure (6.9% vs 5.7%, respectively), septic shock (4.1% vs 6.5%), cardiac arrest (4.3% vs 5.7%), multiorgan failure (4.6% vs 5.5%), and sepsis (4.6% vs 4.2%). No related serious AEs were reported in the IC43 group. INTERPRETATION: The IC43 100 µg vaccine was well tolerated in this large population of medically ill, mechanically ventilated patients. The vaccine achieved high immunogenicity but provided no clinical benefit over placebo in terms of overall mortality. TRIAL REGISTRATION: https://clinicaltrials.gov (NCT01563263). Registration was sent to ClinicalTrials.gov on March 14, 2012, but posted by ClinicalTrials.gov on March 26, 2012. The first subject was included in the trial on March 22, 2012.

Update on extracorporeal carbon dioxide removal: a comprehensive review on principles, indications, efficiency, and complications.

TECHNOLOGY: Extracorporeal carbon dioxide removal means the removal of carbon dioxide from the blood across a gas exchange membrane without substantially improving oxygenation. Carbon dioxide removal is possible with substantially less extracorporeal blood flow than needed for oxygenation. Techniques for extracorporeal carbon dioxide removal include (1) pumpless arterio-venous circuits, (2) low-flow venovenous circuits based on the technology of continuous renal replacement therapy, and (3) venovenous circuits based on extracorporeal membrane oxygenation technology. INDICATIONS: Extracorporeal carbon dioxide removal has been shown to enable more protective ventilation in acute respiratory distress syndrome patients, even beyond the so-called "protective" level. Although experimental data suggest a benefit on ventilator induced lung injury, no hard clinical evidence with respect to improved outcome exists. In addition, extracorporeal carbon dioxide removal is a tool to avoid intubation and mechanical ventilation in patients with acute exacerbated chronic obstructive pulmonary disease failing non-invasive ventilation. This concept has been shown to be effective in 56-90% of patients. Extracorporeal carbon dioxide removal has also been used in ventilated patients with hypercapnic respiratory failure to correct acidosis, unload respiratory muscle burden, and facilitate weaning. In patients suffering from terminal fibrosis awaiting lung transplantation, extracorporeal carbon dioxide removal is able to correct acidosis and enable spontaneous breathing during bridging. Keeping these patients awake, ambulatory, and breathing spontaneously is associated with favorable outcome. COMPLICATIONS: Complications of extracorporeal carbon dioxide removal are mostly associated with vascular access and deranged hemostasis leading to bleeding. Although the spectrum of complications may differ, no technology offers advantages with respect to rate and severity of complications. So called "high-extraction systems" working with higher blood flows and larger membranes may be more effective with respect to clinical goals.

Interleukin 1 Receptor Antagonist Anakinra, Intravenous Immunoglobulin, and Corticosteroids in the Management of Critically Ill Adult Patients With Hemophagocytic Lymphohistiocytosis.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) causes multiple organ dysfunction frequently leading to intensive care unit (ICU) referral and/or death. We report on a series of critically ill adult patients treated with a non-etoposide-based regimen including interleukin 1 antagonist anakinra, intravenous immunoglobulin (IVIG), and/or corticosteroids (CS) for HLH. METHODS: Eight adult (≥18 years) ICU patients having received treatment with anakinra ± IVIG ± CS for HLH between March 2014 and March 2016 at a large tertiary care university hospital (Medical University of Vienna, Vienna, Austria) were retrospectively analyzed. RESULTS: Eight patients (median age: 38 years; range: 20-58 years; 4 males and 4 females) received anakinra together with IVIG (n = 7) and/or high-dose CS (n = 5) for suspected reactive HLH (median H-score: 214; range: 171-288). Seven (88%) patients required vasopressors and invasive mechanical ventilation and 6 (75%) patients required renal replacement therapy (median Sequential Organ Failure Assessment [SOFA] score at HLH diagnosis: 9.5; range: 6-14). Six patients showed a significant decline in the SOFA score at 1 and 2 weeks following treatment initiation (P = .03), and the remainder 2 patients experienced early death. Five patients survived to ICU discharge, 4 of them could further be discharged from hospital (hospital survival rate: 50%). No overt treatment-related toxicity was noted. CONCLUSION: Anakinra in combination with IVIG and/or CS resulted in a hospital survival rate of 50% in 8 critically ill adult patients with HLH despite a vast degree of organ dysfunction and the need for aggressive ICU treatment. Further research on non-etoposide-based treatment strategies for HLH in critically ill adults is warranted.

ECMO without anticoagulation in patients with disease-related severe thrombocytopenia: Feasible but futile?

Severe thrombocytopenia poses a high risk for bleeding thus representing a relative contraindication for anticoagulation and therefore extracorporeal membrane oxygenation (ECMO). We herein report on a series of immunocompromised patients with severe thrombocytopenia undergoing long-term ECMO without systemic anticoagulation. We retrospectively identified seven adult patients with anticoagulation withdrawal for ≥3 days (range 5-317) during venovenous ECMO therapy due to thrombocytopenia < 50 G/L treated in a university-affiliated hospital from January 2013 to April 2017. All ECMO systems used were heparin coated. Overall, 530 ECMO days were observed, 404 (76%) of them without systemic anticoagulation. Platelet count during ECMO treatment was 24 G/L (median, range 1-138), ECMO duration was 35 days (5-317), and ECMO was run without any anticoagulation for 20 days (5-317). Altogether, five clotting events were seen leading to oxygenator exchanges. Bleeding was common including one fatal intracerebral hemorrhage. Altogether, 29 platelet concentrates per patient (7-207) were administered, which correspond to 0.8 per day (0.6-1.3). One patient survived ICU and hospital. In patients with thrombocytopenia, ECMO can be run without anticoagulation even for considerably long periods of time. Bleeding remains common, while clotting events seem to be rare. However, prognosis of this patient population undergoing ECMO support seems grim.

Characteristics and Outcome of Patients After Allogeneic Hematopoietic Stem Cell Transplantation Treated With Extracorporeal Membrane Oxygenation for Acute Respiratory Distress Syndrome.

OBJECTIVES: The acute respiratory distress syndrome is a frequent condition following allogeneic hematopoietic stem cell transplantation. Extracorporeal membrane oxygenation may serve as rescue therapy in refractory acute respiratory distress syndrome but has not been assessed in allogeneic hematopoietic stem cell transplantation recipients. DESIGN: Multicenter, retrospective, observational study. SETTING: ICUs in 12 European tertiary care centers (Austria, Germany, France, and Belgium). PATIENTS: All allogeneic hematopoietic stem cell transplantation recipients treated with venovenous extracorporeal membrane oxygenation for acute respiratory distress syndrome between 2010 and 2015. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Thirty-seven patients, nine of whom underwent noninvasive ventilation at the time of extracorporeal membrane oxygenation initiation, were analyzed. ICU admission occurred at a median of 146 (interquartile range, 27-321) days after allogeneic hematopoietic stem cell transplantation. The main reason for acute respiratory distress syndrome was pneumonia in 81% of patients. All but one patient undergoing noninvasive ventilation at extracorporeal membrane oxygenation initiation had to be intubated thereafter. Overall, seven patients (19%) survived to hospital discharge and were alive and in remission of their hematologic disease after a follow-up of 18 (range, 5-30) months. Only one of 24 patients (4%) initiated on extracorporeal membrane oxygenation within 240 days after allogeneic hematopoietic stem cell transplantation survived compared to six of 13 (46%) of those treated thereafter (p < 0.01). Fourteen patients (38%) experienced bleeding events, of which six (16%) were associated with fatal outcomes. CONCLUSIONS: Discouraging survival rates in patients treated early after allogeneic hematopoietic stem cell transplantation do not support the use of extracorporeal membrane oxygenation for acute respiratory distress syndrome in this group. On the contrary, long-term allogeneic hematopoietic stem cell transplantation recipients otherwise eligible for full-code ICU management may be potential candidates for extracorporeal membrane oxygenation therapy in case of severe acute respiratory distress syndrome failing conventional measures.

Acetylsalicylic acid in critically ill patients: a cross-sectional and a randomized trial.

BACKGROUND: Despite decades of clinical use, the pharmacokinetics and the effects of acetylsalicylic acid (ASA) in critically ill patients remain ill-defined. We aimed to investigate the pharmacokinetics and the effects of different ASA formulations during critical illness. DESIGN: A cross-sectional study and a randomized, parallel-group trial were performed. Critically ill patients under chronic oral ASA treatment (100 mg enteric-coated) were screened for high 'on-treatment' platelet reactivity (HTPR) according to arachidonic acid-induced whole-blood aggregometry. Thirty patients with HTPR were randomized to receive 100 mg ASA intravenously, 100 mg enteric-coated ASA bid (bis in die) or 81 mg chewable ASA (n = 10 per group). Serum thromboxane B2 (TXB2) levels, ASA and salicylic acid levels were quantified. RESULTS: Of 66 patients, 85% (95% confidence intervals 74-93%) had HTPR. Compared to baseline infusion of 100 mg, ASA significantly reduced platelet aggregation after 24 h to median 80% (Quartiles: 66-84%). Intake of 81 mg chewable ASA significantly reduced platelet aggregation to 75% (54-86%) after four hours, but increased it to 117% after 24 h (81-163%). Treatment with 100 mg enteric-coated ASA bid decreased platelet aggregation after 24 h to median 56% (52-113%). Baseline TXB2 levels were median 0·35 ng/mL (0·07-0·94). Infusion of ASA or intake of 100 mg ASA bid reduced TXB2 levels to 0·07-0·18 ng/mL after 24 h, respectively. Chewable ASA reduced TXB2 levels only transiently. Pharmacokinetic analysis revealed highly variable absorption patterns of oral ASA formulations. CONCLUSION: There is a very high prevalence of HTPR in critically ill patients on peroral ASA therapy, caused by an incomplete suppression of TXB2 and/or by impaired absorption of ASA.

A case report of septic shock syndrome caused by S. pneumoniae in an immunocompromised patient despite of vaccination.

BACKGROUND AND CASE PRESENTATION: We report a case of septic shock syndrome caused by Streptococcus pneumoniae in a patient who had undergone splenectomy due to an autoimmune lymphoproliferative syndrome (ALPS), which is characterized as a dysfunction of immunoregulation. Although the patient was vaccinated with a conjugated polysaccharide vaccine after the splenectomy, he was still susceptible to S. pneumoniae infection, because the isolated serovar (24F), a serovar long thought to be apathogenic, is not covered by any vaccine currently approved, neither a conjugated nor an unconjugated polysaccharide one. CONCLUSIONS: This case demonstrates that, due to presence of different serovars, also infections with bacteria against which patients are vaccinated have to be considered as differential diagnosis. Although vaccine development has extended the coverage of S. pneumoniae from 7 to 23 serovars within recent years, there is still demand for novel vaccines which can provide broader protection also against so-thought "apathogenic" strains, especially for groups at high risk.

Extracorporeal CO2 removal as bridge to lung transplantation in life-threatening hypercapnia.

In patients awaiting lung transplantation (LTX), adequate gas exchange may not be sufficiently achieved by mechanical ventilation alone if acute respiratory decompensation arises. We report on 20 patients with life-threatening hypercapnia who received extracorporeal CO2 removal (ECCO2-R) by means of the interventional lung assist (ILA®, Novalung) as bridge to LTX. The most common underlying diagnoses were bronchiolitis obliterans syndrome, cystic fibrosis, and idiopathic pulmonary fibrosis, respectively. The type of ILA was pumpless arteriovenous or pump-driven venovenous (ILA activve®, Novalung) in 10 patients each. ILA bridging was initiated in 15 invasively ventilated and five noninvasively ventilated patients, of whom one had to be intubated prior to LTX. Hypercapnia and acidosis were effectively corrected in all patients within the first 12 h of ILA therapy: PaCO2 declined from 109 (70-146) to 57 (45-64) mmHg, P < 0.0001; pH increased from 7.20 (7.06-7.28) to 7.39 (7.35-7.49), P < 0.0001. Four patients were switched to extracorporeal membrane oxygenation due to progressive hypoxia or circulatory failure. Nineteen patients (95%) were successfully transplanted. Hospital and 1-year survival was 75 and 72%, respectively. Bridging to LTX with ECCO2-R delivered by arteriovenous pumpless or venovenous pump-driven ILA is feasible and associated with high transplantation and survival rates.