Microaxial Flow Pump or Standard Care in Infarct-Related Cardiogenic Shock.

BACKGROUND: The effects of temporary mechanical circulatory support with a microaxial flow pump on mortality among patients with ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock remains unclear. METHODS: In an international, multicenter, randomized trial, we assigned patients with STEMI and cardiogenic shock to receive a microaxial flow pump (Impella CP) plus standard care or standard care alone. The primary end point was death from any cause at 180 days. A composite safety end point was severe bleeding, limb ischemia, hemolysis, device failure, or worsening aortic regurgitation. RESULTS: A total of 360 patients underwent randomization, of whom 355 were included in the final analysis (179 in the microaxial-flow-pump group and 176 in the standard-care group). The median age of the patients was 67 years, and 79.2% were men. Death from any cause occurred in 82 of 179 patients (45.8%) in the microaxial-flow-pump group and in 103 of 176 patients (58.5%) in the standard-care group (hazard ratio, 0.74; 95% confidence interval [CI], 0.55 to 0.99; P = 0.04). A composite safety end-point event occurred in 43 patients (24.0%) in the microaxial-flow-pump group and in 11 (6.2%) in the standard-care group (relative risk, 4.74; 95% CI, 2.36 to 9.55). Renal-replacement therapy was administered to 75 patients (41.9%) in the microaxial-flow-pump group and to 47 patients (26.7%) in the standard-care group (relative risk, 1.98; 95% CI, 1.27 to 3.09). CONCLUSIONS: The routine use of a microaxial flow pump with standard care in the treatment of patients with STEMI-related cardiogenic shock led to a lower risk of death from any cause at 180 days than standard care alone. The incidence of a composite of adverse events was higher with the use of the microaxial flow pump. (Funded by the Danish Heart Foundation and Abiomed; DanGer Shock ClinicalTrials.gov number, NCT01633502.).

Mild Hypercapnia or Normocapnia after Out-of-Hospital Cardiac Arrest.

BACKGROUND: Guidelines recommend normocapnia for adults with coma who are resuscitated after out-of-hospital cardiac arrest. However, mild hypercapnia increases cerebral blood flow and may improve neurologic outcomes. METHODS: We randomly assigned adults with coma who had been resuscitated after out-of-hospital cardiac arrest of presumed cardiac or unknown cause and admitted to the intensive care unit (ICU) in a 1:1 ratio to either 24 hours of mild hypercapnia (target partial pressure of arterial carbon dioxide [Paco2], 50 to 55 mm Hg) or normocapnia (target Paco2, 35 to 45 mm Hg). The primary outcome was a favorable neurologic outcome, defined as a score of 5 (indicating lower moderate disability) or higher, as assessed with the use of the Glasgow Outcome Scale-Extended (range, 1 [death] to 8, with higher scores indicating better neurologic outcome) at 6 months. Secondary outcomes included death within 6 months. RESULTS: A total of 1700 patients from 63 ICUs in 17 countries were recruited, with 847 patients assigned to targeted mild hypercapnia and 853 to targeted normocapnia. A favorable neurologic outcome at 6 months occurred in 332 of 764 patients (43.5%) in the mild hypercapnia group and in 350 of 784 (44.6%) in the normocapnia group (relative risk, 0.98; 95% confidence interval [CI], 0.87 to 1.11; P = 0.76). Death within 6 months after randomization occurred in 393 of 816 patients (48.2%) in the mild hypercapnia group and in 382 of 832 (45.9%) in the normocapnia group (relative risk, 1.05; 95% CI, 0.94 to 1.16). The incidence of adverse events did not differ significantly between groups. CONCLUSIONS: In patients with coma who were resuscitated after out-of-hospital cardiac arrest, targeted mild hypercapnia did not lead to better neurologic outcomes at 6 months than targeted normocapnia. (Funded by the National Health and Medical Research Council of Australia and others; TAME ClinicalTrials.gov number, NCT03114033.).

Hypothermia versus Normothermia after Out-of-Hospital Cardiac Arrest.

BACKGROUND: Targeted temperature management is recommended for patients after cardiac arrest, but the supporting evidence is of low certainty. METHODS: In an open-label trial with blinded assessment of outcomes, we randomly assigned 1900 adults with coma who had had an out-of-hospital cardiac arrest of presumed cardiac or unknown cause to undergo targeted hypothermia at 33°C, followed by controlled rewarming, or targeted normothermia with early treatment of fever (body temperature, ≥37.8°C). The primary outcome was death from any cause at 6 months. Secondary outcomes included functional outcome at 6 months as assessed with the modified Rankin scale. Prespecified subgroups were defined according to sex, age, initial cardiac rhythm, time to return of spontaneous circulation, and presence or absence of shock on admission. Prespecified adverse events were pneumonia, sepsis, bleeding, arrhythmia resulting in hemodynamic compromise, and skin complications related to the temperature management device. RESULTS: A total of 1850 patients were evaluated for the primary outcome. At 6 months, 465 of 925 patients (50%) in the hypothermia group had died, as compared with 446 of 925 (48%) in the normothermia group (relative risk with hypothermia, 1.04; 95% confidence interval [CI], 0.94 to 1.14; P = 0.37). Of the 1747 patients in whom the functional outcome was assessed, 488 of 881 (55%) in the hypothermia group had moderately severe disability or worse (modified Rankin scale score ≥4), as compared with 479 of 866 (55%) in the normothermia group (relative risk with hypothermia, 1.00; 95% CI, 0.92 to 1.09). Outcomes were consistent in the prespecified subgroups. Arrhythmia resulting in hemodynamic compromise was more common in the hypothermia group than in the normothermia group (24% vs. 17%, P<0.001). The incidence of other adverse events did not differ significantly between the two groups. CONCLUSIONS: In patients with coma after out-of-hospital cardiac arrest, targeted hypothermia did not lead to a lower incidence of death by 6 months than targeted normothermia. (Funded by the Swedish Research Council and others; TTM2 ClinicalTrials.gov number, NCT02908308.).

Non-COVID-19 intensive care admissions during the pandemic: a multinational registry-based study.

BACKGROUND: The COVID-19 pandemic resulted in a large number of critical care admissions. While national reports have described the outcomes of patients with COVID-19, there is limited international data of the pandemic impact on non-COVID-19 patients requiring intensive care treatment. METHODS: We conducted an international, retrospective cohort study using 2019 and 2020 data from 11 national clinical quality registries covering 15 countries. Non-COVID-19 admissions in 2020 were compared with all admissions in 2019, prepandemic. The primary outcome was intensive care unit (ICU) mortality. Secondary outcomes included in-hospital mortality and standardised mortality ratio (SMR). Analyses were stratified by the country income level(s) of each registry. FINDINGS: Among 1 642 632 non-COVID-19 admissions, there was an increase in ICU mortality between 2019 (9.3%) and 2020 (10.4%), OR=1.15 (95% CI 1.14 to 1.17, p<0.001). Increased mortality was observed in middle-income countries (OR 1.25 95% CI 1.23 to 1.26), while mortality decreased in high-income countries (OR=0.96 95% CI 0.94 to 0.98). Hospital mortality and SMR trends for each registry were consistent with the observed ICU mortality findings. The burden of COVID-19 was highly variable, with COVID-19 ICU patient-days per bed ranging from 0.4 to 81.6 between registries. This alone did not explain the observed non-COVID-19 mortality changes. INTERPRETATION: Increased ICU mortality occurred among non-COVID-19 patients during the pandemic, driven by increased mortality in middle-income countries, while mortality decreased in high-income countries. The causes for this inequity are likely multi-factorial, but healthcare spending, policy pandemic responses, and ICU strain may play significant roles.

The use of prone position ventilation in Danish patients with COVID-19-induced severe acute respiratory distress syndrome treated with veno-venous extracorporeal membrane oxygenation: A nationwide cohort study with focus on pulmonary effects.

BACKGROUND: Prone position ventilation (PPV) is recommended for patients with COVID-19 induced severe Adult Respiratory Distress Syndrome (ARDS) and is used for patients supported with V-V ECMO as well. The purpose of this study was to describe the use of PPV in these patients focusing on physiological effects with the hypothesis that PPV could reduce oxygen need and improve dynamic compliance. METHODS: This study was a nationwide retrospective analysis of all COVID-19 patients in Denmark from March 2020 - December 2021 with severe ARDS and need of V-V ECMO support. Data on the number of patients treated with PPV, number of PPV sessions, timing, the time spent in prone position, pulmonary physiological response types with analysis of variables affecting the response are reported. RESULTS: Out of 68 patients 44 were treated with 220 PPV sessions and a positive clinical response was observed in 80% of patients but only in 45% of sessions. On a single session level, increased compliance was observed in 38% and increased oxygenation in only 15% of 220 sessions, with within-patient heterogeneity. Higher dynamic compliance at the beginning of a PPV session was associated with a lower delta change in dynamic compliance during PPV. The response to a PPV session could not be predicted by the response in the prior session. Dynamic compliance did not change during the ECMO course. CONCLUSION: Eighty percent of patients responded positively during a PPV session, but this was not associated with overall pulmonary improvement. On a single patient level, responses were heterogenous and only 45% of sessions resulted in clinical improvement. Response in dynamic compliance was associated with starting values of compliance.

Platelet Function in Acute Kidney Injury: A Systematic Review and a Cohort Study.

Acute kidney injury (AKI) patients have increased bleeding risk, which could be partially due to acquired platelet dysfunction. We conducted a systematic review and a cohort study to investigate platelet function and count in AKI and their association with AKI-related bleeding and mortality. Through a systematic literature search in PubMed and Embase, we identified 9 studies reporting platelet function and 56 studies reporting platelet count or platelet indices in AKI patients. Overall, platelet aggregation was reduced in AKI patients in nonintensive care unit (ICU) settings but not in ICU settings, except that reduced aggregation was associated with renal replacement therapy. Thrombocytopenia in AKI was frequent and often predictive of mortality. In our cohort study, we prospectively included 54 adult ICU patients who developed AKI within 24 hours of ICU admission and 33 non-AKI ICU controls. Platelet function was measured with light transmission aggregometry and flow cytometry. AKI patients bled more frequently than non-AKI patients (p = 0.04), and bleeding was associated with increased 30-day mortality in AKI (p = 0.02). However, platelet function was not different between AKI and non-AKI patients (aggregation: all p > 0.52; flow cytometry: all p > 0.07) and platelet function was not associated with bleeding in AKI. In conclusion, a reduced platelet count is frequent in AKI, but the literature on platelet function in AKI is sparse. In a cohort study, we demonstrated that patients with AKI within 24 hours of ICU admission exhibited increased bleeding tendency but this was not associated with reduced platelet function.

The Nordic perioperative and intensive care registries-Collaboration and research possibilities.

BACKGROUND: The Nordic perioperative and intensive care registries have been built up during the last 25 years to improve quality in intensive and perioperative care. We aimed to describe the Nordic perioperative and intensive care registries and to highlight possibilities and challenges in future research collaboration between these registries. MATERIAL AND METHOD: We present an overview of the following Nordic registries: Swedish Perioperative Registry (SPOR), the Danish Anesthesia Database (DAD), the Finnish Perioperative Database (FIN-AN), the Icelandic Anesthesia Database (IS-AN), the Danish Intensive Care Database (DID), the Swedish Intensive Care Registry (SIR), the Finnish Intensive Care Consortium, the Norwegian Intensive Care and Pandemic Registry (NIPaR), and the Icelandic Intensive Care Registry (IS-ICU). RESULTS: Health care systems and patient populations are similar in the Nordic countries. Despite certain differences in data structure and clinical variables, the perioperative and intensive care registries have enough in common to enable research collaboration. In the future, even a common Nordic registry could be possible. CONCLUSION: Collaboration between the Nordic perioperative and intensive care registries is both possible and likely to produce research of high quality. Research collaboration between registries may have several add-on effects and stimulate international standardization regarding definitions, scoring systems, and benchmarks, thereby improving overall quality of care.

Long-term outcomes in COVID-19 patients admitted to intensive care in Denmark: A nationwide observational study.

BACKGROUND: Among ICU patients with COVID-19, it is largely unknown how the overall outcome and resource use have changed with time, different genetic variants, and vaccination status. METHODS: For all Danish ICU patients with COVID-19 from March 10, 2020 to March 31, 2022, we manually retrieved data on demographics, comorbidities, vaccination status, use of life support, length of stay, and vital status from medical records. We compared patients based on the period of admittance and vaccination status and described changes in epidemiology related to the Omicron variant. RESULTS: Among all 2167 ICU patients with COVID-19, 327 were admitted during the first (March 10-19, 2020), 1053 during the second (May 20, 2020 to June 30, 2021) and 787 during the third wave (July 1, 2021 to March 31, 2022). We observed changes over the three waves in age (median 72 vs. 68 vs. 65 years), use of invasive mechanical ventilation (81% vs. 58% vs. 51%), renal replacement therapy (26% vs. 13% vs. 12%), extracorporeal membrane oxygenation (7% vs. 3% vs. 2%), duration of invasive mechanical ventilation (median 13 vs. 13 vs. 9 days) and ICU length of stay (median 13 vs. 10 vs. 7 days). Despite these changes, 90-day mortality remained constant (36% vs. 35% vs. 33%). Vaccination rates among ICU patients were 42% as compared to 80% in society. Unvaccinated versus vaccinated patients were younger (median 57 vs. 73 years), had less comorbidity (50% vs. 78%), and had lower 90-day mortality (29% vs. 51%). Patient characteristics changed significantly after the Omicron variant became dominant including a decrease in the use of COVID-specific pharmacological agents from 95% to 69%. CONCLUSIONS: In Danish ICUs, the use of life support declined, while mortality seemed unchanged throughout the three waves of COVID-19. Vaccination rates were lower among ICU patients than in society, but the selected group of vaccinated patients admitted to the ICU still had very severe disease courses. When the Omicron variant became dominant a lower fraction of SARS-CoV-2 positive patients received COVID treatment indicating other causes for ICU admission.

Use of prone position ventilation in patients with COVID-19 induced severe ARDS supported with V-V ECMO: A danish cohort study with focus on adverse events.

INTRODUCTION: Prone position ventilation (PPV) of patients with adult respiratory distress syndrome (ARDS) supported with veno-venous extracorporeal membrane oxygenation (V-V ECMO) may improve oxygenation and alveolar recruitment and is recommended when extensive dorsal consolidations are present, but only few data regarding adverse events (AE) related to PPV in this group of patients have been published. METHODS: Nationwide retrospective analysis of 68 COVID-19 patients admitted from March 2020 - December 2021 with severe ARDS and need of V-V ECMO support. The number of patients treated with PPV, number of PPV-events, timing, the time spent in prone position, number and causes of AE are reported. Causes to stop the PPV regimen and risk factors for AE were explored. RESULTS: 44 out of 68 patients were treated with PPV, and 220 PPV events are evaluated. AE were identified in 99 out of 220 (45%) PPV events and occurred among 31 patients (71%). 1 fatal PPV related AE was registered. Acute supination occurred in 19 events (9%). Causes to stop the PPV regimen were almost equally distributed between effect (weaned from ECMO), no effect, death (of other reasons) and AE. Frequent causes of AE were pressures sores and ulcers, hypoxia, airway related and ECMO circuit related. Most AE occurred during patients first or second PPV event. CONCLUSIONS: PPV treatment was found to carry a high incidence of PPV related AE in these patients. Causes and preventive measures to reduce occurrence of PPV related AE during V-V ECMO support need further exploration.

The effect of immunosuppressants on the prognosis of SARS-CoV-2 infection.

BACKGROUND: Immunosuppression may worsen severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We conducted a nationwide cohort study of the effect of exposure to immunosuppressants on the prognosis of SARS-CoV-2 infection in Denmark. METHODS: We identified all SARS-CoV-2 test-positive patients from February 2020 to October 2020 and linked healthcare data from nationwide registers, including prescriptions for the exposure (immunosuppressant drugs). We estimated relative risks of hospital admission, intensive care unit (ICU) admission and death (each studied independently up to 30 days from testing) with a log-linear binomial regression adjusted for confounders using a propensity score-based matching weights model. RESULTS: A composite immunosuppressant exposure was associated with a significantly increased risk of death (adjusted relative risk 1.56 (95% CI 1.10-2.22)). The increased risk of death was mainly driven by exposure to systemic glucocorticoids (adjusted relative risk 2.38 (95% CI 1.72-3.30)), which were also associated with an increased risk of hospital admission (adjusted relative risk 1.34 (95% CI 1.10-1.62)), but not of ICU admission (adjusted relative risk 1.76 (95% CI 0.93-3.35)); these risks were greater for high cumulative doses of glucocorticoids than for moderate doses. Exposure to selective immunosuppressants, tumour necrosis factor inhibitors or interleukin inhibitors was not associated with an increased risk of hospitalisation, ICU admission or death, nor was exposure to calcineurin inhibitors, other immunosuppressants, hydroxychloroquine or chloroquine. CONCLUSIONS: Exposure to glucocorticoids was associated with increased risks of hospital admission and death. Further investigation is needed to determine the optimal management of coronavirus disease 2019 (COVID-19) in patients with pre-morbid glucocorticoid usage, specifically whether these patients require altered doses of glucocorticoids.

Dynamic Hemostasis and Fibrinolysis Assays in Intensive Care COVID-19 Patients and Association with Thrombosis and Bleeding-A Systematic Review and a Cohort Study.

Patients admitted to the intensive care unit (ICU) with coronavirus disease 2019 (COVID-19), the infectious pathology caused by severe acute respiratory syndrome coronavirus 2, have a high risk of thrombosis, though the precise mechanisms behind this remain unclarified. A systematic literature search in PubMed and EMBASE identified 18 prospective studies applying dynamic coagulation assays in ICU COVID-19 patients. Overall, these studies revealed normal or slightly reduced primary hemostasis, prolonged clot initiation, but increased clot firmness. Thrombin generation assay parameters generally were equivalent to the control groups or within reference range. Fibrinolysis assays showed increased clot resistance. Only six studies related their findings to clinical outcome. We also prospectively included 51 COVID-19 patients admitted to the ICU. Blood samples were examined on day 1, 3-4, and 7-8 with platelet function tests, rotational thromboelastometry (ROTEM), in vivo and ex vivo thrombin generation, and clot lysis assay. Data on thrombosis, bleeding, and mortality were recorded during 30 days. Primary hemostasis was comparable to healthy controls, but COVID-19 patients had longer ROTEM-clotting times and higher maximum clot firmness than healthy controls. Ex vivo thrombin generation was similar to that of healthy controls while in vivo thrombin generation markers, thrombin-antithrombin (TAT) complex, and prothrombin fragment 1 + 2 (F1 + 2) were higher in ICU COVID-19 patients than in healthy controls. Impaired fibrinolysis was present at all time points. TAT complex and F1 + 2 levels were significantly higher in patients developing thrombosis (n = 16) than in those without. In conclusion, only few previous studies employed dynamic hemostasis assays in COVID-19 ICU-patients and failed to reveal a clear association with development of thrombosis. In ICU COVID-19 patients, we confirmed normal platelet aggregation, while in vivo thrombin generation was increased and fibrinolysis decreased. Thrombosis may be driven by increased thrombin formation in vivo.

Short-term mortality of patients ≥80 years old admitted to European intensive care units: an international observational study.

BACKGROUND: Limited evidence suggests variation in mortality of older critically ill adults across Europe. We aimed to investigate regional differences in mortality among very old ICU patients. METHODS: Multilevel analysis of two international prospective cohort studies. We included patients ≥80 yr old from 322 ICUs located in 16 European countries. The primary outcome was mortality within 30 days from admission to the ICU. Results are presented as n (%) with 95% confidence intervals and odds ratios (ORs). RESULTS: Of 8457 patients, 2944 (36.9% [35.9-38.0%]) died within 30 days. Crude mortality rates varied widely between participating countries (from 10.1% [6.4-15.6%] to 45.1% [41.1-49.2%] in the ICU and from 21.3% [16.3-28.9%] to 55.3% [51.1-59.5%] within 30 days). After adjustment for confounding variables, the variation in 30-day mortality between countries was substantially smaller than between ICUs (median OR 1.14 vs 1.58). Healthcare expenditure per capita (OR=0.84 per $1000 [0.75-0.94]) and social health insurance framework (OR=1.43 [1.01-2.01]) were associated with ICU mortality, but the direction and magnitude of these relationships was uncertain in 30-day follow-up. Volume of admissions was associated with lower mortality both in the ICU (OR=0.81 per 1000 annual ICU admissions [0.71-0.94]) and in 30-day follow-up (OR=0.86 [0.76-0.97]). CONCLUSION: The apparent variation in short-term mortality rates of older adults hospitalised in ICUs across Europe can be largely attributed to differences in the clinical profile of patients admitted. The volume-outcome relationship identified in this population requires further investigation.

Senicapoc treatment in COVID-19 patients with severe respiratory insufficiency-A randomized, open-label, phase II trial.

BACKGROUND: The aim of the current study was to determine if treatment with senicapoc, improves the PaO2 /FiO2 ratio in patients with COVID-19 and severe respiratory insufficiency. METHODS: Investigator-initiated, randomized, open-label, phase II trial in four intensive care units (ICU) in Denmark. We included patients aged ≥18 years and admitted to an ICU with severe respiratory insufficiency due to COVID-19. The intervention consisted of 50 mg enteral senicapoc administered as soon as possible after randomization and again after 24 h. Patients in the control group received standard care only. The primary outcome was the PaO2 /FiO2 ratio at 72 h. RESULTS: Twenty patients were randomized to senicapoc and 26 patients to standard care. Important differences existed in patient characteristics at baseline, including more patients being on non-invasive/invasive ventilation in the control group (54% vs. 35%). The median senicapoc concentration at 72 h was 62.1 ng/ml (IQR 46.7-71.2). The primary outcome, PaO2 /FiO2 ratio at 72 h, was significantly lower in the senicapoc group (mean 19.5 kPa, SD 6.6) than in the control group (mean 24.4 kPa, SD 9.2) (mean difference -5.1 kPa [95% CI -10.2, -0.04] p = .05). The 28-day mortality in the senicapoc group was 2/20 (10%) compared with 6/26 (23%) in the control group (OR 0.36 95% CI 0.06-2.07, p = .26). CONCLUSIONS: Treatment with senicapoc resulted in a significantly lower PaO2 /FiO2 ratio at 72 h with no differences for other outcomes.

Long-term cognitive and functional status in Danish ICU patients with COVID-19.

BACKGROUND: ICU admission due to COVID-19 may result in cognitive and physical impairment. We investigated the long-term cognitive and physical status of Danish ICU patients with COVID-19. METHODS: We included all patients with COVID-19 admitted to Danish ICUs between March 10 and May 19, 2020. Patients were the contacted prospectively at 6 and 12 months for follow-up. Our primary outcomes were cognitive function and frailty at 6 and 12 months after ICU admission, estimated by the Mini Montreal Cognitive Assessment, and the Clinical Frailty Scale. Secondary outcomes were 6- and 12-month mortality, health-related quality of life (HRQoL) assessed by EQ-5D-5L, functional status (Barthel activities of daily living and Lawton-Brody instrumental activities of daily living), and fatigue (Fatigue Assessment Scale). The study had no information on pre-ICU admission status for the participants. RESULTS: A total of 326 patients were included. The 6- and 12-month mortality was 37% and 38%, respectively. Among the 204 six-month survivors, 105 (51%) participated in the 6-month follow-up; among the 202 twelve-month survivors, 95 (47%) participated in the 12-month follow-up. At 6 months, cognitive scores indicated impairment for 26% (95% confidence interval [CI], 11.4-12.4) and at 12 months for 17% (95% CI, 12.0-12.8) of participants. Frailty was indicated in 20% (95% CI, 3.4-3.9) at 6 months, and for 18% (95% CI, 3.3-3.8) at 12 months. Fatigue was reported by 52% at 6 months, and by 47% at 12 months. For HRQoL, moderate, severe, or extreme health problems were reported by 28% at 6 months, and by 25% at 12 months. CONCLUSION: Long-term cognitive, functional impairment was found in up to one in four of patients surviving intensive care for COVID-19. Fatigue was present in nearly half the survivors at both 6 and 12 months. However, pre-ICU admission status of the patients was unknown.

Development of a core outcome set for general intensive care unit patients-A protocol.

INTRODUCTION: Different outcomes are reported in randomised clinical trials (RCTs) in intensive care unit (ICU) patients, and no core outcome set (COS) is available for ICU patients in general. Accordingly, we aim to develop a COS for ICU patients in general. METHODS: The COS will be developed in accordance with the Core Outcome Measures in Effectiveness Trials (COMET) Handbook, using a modified Delphi consensus process and semi-structured interviews involving adults who have survived acute admission to an ICU, family members, clinicians, researchers and other stakeholders. The modified Delphi process will include two steps. Step 1: conduction of a modified Delphi survey, developed and informed by combining the outputs of a literature search of outcomes in previous COSs and semi-structured interviews with key stakeholders. We plan at least two survey rounds to obtain consensus and refine the COS. Step 2: a consensus process regarding instruments or definitions to be recommended for the measurements of the outcomes selected in Step 1. A 'patient and public involvement panel' consisting of a smaller group of patients, family members, clinicians and researchers will be included in the development, analysis and interpretation of the COS. DISCUSSION: The outlined multiple method studies will establish a COS for ICU patients in general, which may be used to increase the standardisation and comparability of results of RCTs conducted in patients in the ICU setting.

Changes over time in characteristics, resource use and outcomes among ICU patients with COVID-19-A nationwide, observational study in Denmark.

BACKGROUND: Characteristics and care of intensive care unit (ICU) patients with COVID-19 may have changed during the pandemic, but longitudinal data assessing this are limited. We compared patients with COVID-19 admitted to Danish ICUs in the first wave with those admitted later. METHODS: Among all Danish ICU patients with COVID-19, we compared demographics, chronic comorbidities, use of organ support, length of stay and vital status of those admitted 10 March to 19 May 2020 (first wave) versus 20 May 2020 to 30 June 2021. We analysed risk factors for death by adjusted logistic regression analysis. RESULTS: Among all hospitalised patients with COVID-19, a lower proportion was admitted to ICU after the first wave (13% vs. 8%). Among all 1374 ICU patients with COVID-19, 326 were admitted during the first wave. There were no major differences in patient's characteristics or mortality between the two periods, but use of invasive mechanical ventilation (81% vs. 58% of patients), renal replacement therapy (26% vs. 13%) and ECMO (8% vs. 3%) and median length of stay in ICU (13 vs. 10 days) and in hospital (20 vs. 17 days) were all significantly lower after the first wave. Risk factors for death were higher age, larger burden of comorbidities (heart failure, pulmonary disease and kidney disease) and active cancer, but not admission during or after the first wave. CONCLUSIONS: After the first wave of COVID-19 in Denmark, a lower proportion of hospitalised patients with COVID-19 were admitted to ICU. Among ICU patients, use of organ support was lower and length of stay was reduced, but mortality rates remained at a relatively high level.

Mechanical circulatory support for refractory out-of-hospital cardiac arrest: a Danish nationwide multicenter study.

BACKGROUND: Mechanical circulatory support (MCS) with either extracorporeal membrane oxygenation or Impella has shown potential as a salvage therapy for patients with refractory out-of-hospital cardiac arrest (OHCA). The objective of this study was to describe the gradual implementation, survival and adherence to the national consensus with respect to use of MCS for OHCA in Denmark, and to identify factors associated with outcome. METHODS: This retrospective, observational cohort study included patients receiving MCS for OHCA at all tertiary cardiac arrest centers (n = 4) in Denmark between July 2011 and December 2020. Logistic regression and Kaplan-Meier survival analysis were used to determine association with outcome. Outcome was presented as survival to hospital discharge with good neurological outcome, 30-day survival and predictors of 30-day mortality. RESULTS: A total of 259 patients were included in the study. Thirty-day survival was 26%. Sixty-five (25%) survived to hospital discharge and a good neurological outcome (Glasgow-Pittsburgh Cerebral Performance Categories 1-2) was observed in 94% of these patients. Strict adherence to the national consensus showed a 30-day survival rate of 30% compared with 22% in patients violating one or more criteria. Adding criteria to the national consensus such as signs of life during cardiopulmonary resuscitation (CPR), pre-hospital low-flow < 100 min, pH > 6.8 and lactate < 15 mmol/L increased the survival rate to 48%, but would exclude 58% of the survivors from the current cohort. Logistic regression identified asystole (RR 1.36, 95% CI 1.18-1.57), pulseless electrical activity (RR 1.20, 95% CI 1.03-1.41), initial pH < 6.8 (RR 1.28, 95% CI 1.12-1.46) and lactate levels > 15 mmol/L (RR 1.16, 95% CI 1.16-1.53) as factors associated with increased risk of 30-day mortality. Patients presenting signs of life during CPR had reduced risk of 30-day mortality (RR 0.63, 95% CI 0.52-0.76). CONCLUSIONS: A high survival rate with a good neurological outcome was observed in this Danish population of patients treated with MCS for OHCA. Stringent patient selection for MCS may produce higher survival rates but potentially withholds life-saving treatment in a significant proportion of survivors.

Relationship between the Clinical Frailty Scale and short-term mortality in patients ≥ 80 years old acutely admitted to the ICU: a prospective cohort study.

BACKGROUND: The Clinical Frailty Scale (CFS) is frequently used to measure frailty in critically ill adults. There is wide variation in the approach to analysing the relationship between the CFS score and mortality after admission to the ICU. This study aimed to evaluate the influence of modelling approach on the association between the CFS score and short-term mortality and quantify the prognostic value of frailty in this context. METHODS: We analysed data from two multicentre prospective cohort studies which enrolled intensive care unit patients ≥ 80 years old in 26 countries. The primary outcome was mortality within 30-days from admission to the ICU. Logistic regression models for both ICU and 30-day mortality included the CFS score as either a categorical, continuous or dichotomous variable and were adjusted for patient's age, sex, reason for admission to the ICU, and admission Sequential Organ Failure Assessment score. RESULTS: The median age in the sample of 7487 consecutive patients was 84 years (IQR 81-87). The highest fraction of new prognostic information from frailty in the context of 30-day mortality was observed when the CFS score was treated as either a categorical variable using all original levels of frailty or a nonlinear continuous variable and was equal to 9% using these modelling approaches (p < 0.001). The relationship between the CFS score and mortality was nonlinear (p < 0.01). CONCLUSION: Knowledge about a patient's frailty status adds a substantial amount of new prognostic information at the moment of admission to the ICU. Arbitrary simplification of the CFS score into fewer groups than originally intended leads to a loss of information and should be avoided. Trial registration NCT03134807 (VIP1), NCT03370692 (VIP2).

COVID-19 versus influenza A/B supeRInfectionS in the IntenSive care unit (CRISIS): Protocol for a Danish nationwide cohort study.

BACKGROUND: Superinfection following viral infection is a known complication, which may lead to longer hospitalisation and worse outcome. Empirical antibiotic therapy may prevent bacterial superinfections, but may also lead to overuse, adverse effects and development of resistant pathogens. Knowledge about the incidence of superinfections in intensive care unit (ICU) patients with severe Coronavirus Disease 2019 (COVID-19) is limited. METHODS: We will conduct a nationwide cohort study comparing the incidence of superinfections in patients with severe COVID-19 admitted to the ICU compared with ICU patients with influenza A/B in Denmark. We will include approximately 1000 patients in each group from the time period of 1 October 2014 to 30 April 2019 and from 10 March 2020 to 1 March 2021 for patients with influenza and COVID-19, respectively. The primary outcome is any superinfection within 90 days of admission to the ICU. We will use logistic regression analysis comparing COVID-19 with influenza A/B after adjustment for relevant predefined confounders. Secondarily, we will use unadjusted and adjusted logistic regression analyses to assess six potential risk factors (sex, age, cancer [including haematological], immunosuppression and use of life support on day 1 in the ICU) for superinfections and compare outcomes in patients with COVID-19 with/without superinfections, and present descriptive data regarding the superinfections. CONCLUSION: This study will provide important knowledge about superinfections in ICU patients with severe COVID-19.

A systematic approach to weaning from extracorporeal membrane oxygenation in patients with refractory cardiac failure.

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is commonly used to provide haemodynamic support for patients with severe cardiac failure. However, timing ECMO weaning remains challenging. We aimed to examine if an integrative weaning approach based on predefined haemodynamic, respiratory and echocardiographic criteria is associated with successful weaning. METHODS: All patients weaned from ECMO between April 2017 and April 2019 at Aarhus University Hospital, Denmark, were consecutively enrolled. Predefined haemodynamic, respiratory and echocardiographic criteria were assessed before and during ECMO flow reduction. A weaning attempt was commenced in haemodynamic stable patients and patients remaining stable at minimal flow were weaned from ECMO. Comparisons were made between patients who met the criteria for weaning at first attempt and patients who did not meet these criteria. Patients completing a full weaning attempt with no further need for mechanical support within 24 h were defined as successfully weaned. RESULTS: A total of 38 patients were included in the study, of whom 26 (68%) patients met the criteria for weaning. Among these patients, 25 (96%) could be successfully weaned. Successfully weaned patients were younger and had less need for inotropic support and ECMO duration was shorter. Fulfilling the weaning criteria was associated with successful weaning and both favourable 30-d survival and survival to discharge. CONCLUSION: An integrative weaning approach based on haemodynamic, respiratory and echocardiographic criteria may strengthen the clinical decision process in predicting successful weaning in patients receiving ECMO for refractory cardiac failure.