Who to escalate during a pandemic? A retrospective observational study about decision-making during the COVID-19 pandemic in the UK.

BACKGROUND: Optimal decision-making regarding who to admit to critical care in pandemic situations remains unclear. We compared age, Clinical Frailty Score (CFS), 4C Mortality Score and hospital mortality in two separate COVID-19 surges based on the escalation decision made by the treating physician. METHODS: A retrospective analysis of all referrals to critical care during the first COVID-19 surge (cohort 1, March/April 2020) and a late surge (cohort 2, October/November 2021) was undertaken. Patients with confirmed or high clinical suspicion of COVID-19 infection were included. A senior critical care physician assessed all patients regarding their suitability for potential intensive care unit admission. Demographics, CFS, 4C Mortality Score and hospital mortality were compared depending on the escalation decision made by the attending physician. RESULTS: 203 patients were included in the study, 139 in cohort 1 and 64 in cohort 2. There were no significant differences in age, CFS and 4C scores between the two cohorts. Patients deemed suitable for escalation by clinicians were significantly younger with significantly lower CFS and 4C scores compared with patients who were not deemed to benefit from escalation. This pattern was observed in both cohorts. Mortality in patients not deemed suitable for escalation was 61.8% in cohort 1 and 47.4% in cohort 2 (p<0.001). CONCLUSIONS: Decisions who to escalate to critical care in settings with limited resources pose moral distress on clinicians. 4C score, age and CFS did not change significantly between the two surges but differed significantly between patients deemed suitable for escalation and those deemed unsuitable by clinicians. Risk prediction tools may be useful in a pandemic to supplement clinical decision-making, even though escalation thresholds require adjustments to reflect changes in risk profile and outcomes between different pandemic surges.

A Systematic Review of Anticoagulation Strategies for Patients with Atrial Fibrillation in Critical Care.

BACKGROUND: Atrial fibrillation (AF) is the most common cardiac arrhythmia in critically ill patients. There is a paucity of data assessing the impact of anticoagulation strategies on clinical outcomes for general critical care patients with AF. Our aim was to assess the existing literature to evaluate the effectiveness of anticoagulation strategies used in critical care for AF. METHODS: A systematic literature search was conducted using MEDLINE, EMBASE, CENTRAL, and PubMed databases. Studies reporting anticoagulation strategies for AF in adults admitted to a general critical care setting were assessed for inclusion. RESULTS: Four studies were selected for data extraction. A total of 44,087 patients were identified with AF, of which 17.8 to 49.4% received anticoagulation. The reported incidence of thromboembolic events was 0 to 1.4% for anticoagulated patients, and 0 to 1.3% in nonanticoagulated patients. Major bleeding events were reported in three studies and occurred in 7.2 to 8.6% of the anticoagulated patients and in up to 7.1% of the nonanticoagulated patients. CONCLUSION: There was an increased incidence of major bleeding events in anticoagulated patients with AF in critical care compared with nonanticoagulated patients. There was no significant difference in the incidence of reported thromboembolic events within studies between patients who did and did not receive anticoagulation. However, the outcomes reported within studies were not standardized, therefore, the generalizability of our results to the general critical care population remains unclear. Further data are required to facilitate an evidence-based assessment of the risks and benefits of anticoagulation for critically ill patients with AF.

Current practice in the management of new-onset atrial fibrillation in critically ill patients: a UK-wide survey.

BACKGROUND: New-onset atrial fibrillation (AF) is the most common arrhythmia in critically ill patients. Although evidence base and expert consensus opinion for management have been summarised in several international guidelines, no specific considerations for critically ill patients have been included. We aimed to establish current practice of management of critically ill patients with new-onset AF. METHODS: We designed a short user-friendly online questionnaire. All members of the Intensive Care Society were invited via email containing a link to the questionnaire, which comprised 21 questions. The online survey was conducted between November 2016 and December 2016. RESULTS: The response rate was 397/3152 (12.6%). The majority of respondents (81.1%) worked in mixed Intensive Care Units and were consultants (71.8%). Most respondents (39.5%) would start intervention on patients with fast new-onset AF and stable blood pressure at a heart rate between 120 and 139 beats/min. However, 34.8% of participants would treat all patients who developed new-onset fast AF. Amiodarone and beta-blockers (80.9% and 11.6% of answers) were the most commonly used anti-arrhythmics. A total of 63.8% of respondents do not regularly anti-coagulate critically ill patients with new-onset fast AF, while 30.8% anti-coagulate within 72 hours. A total of 68.0% of survey respondents do not routinely use stroke risk scores in critically ill patients with new-onset AF. A total of 85.4% of participants would consider taking part in a clinical trial investigating treatment of new-onset fast AF in the critically ill. DISCUSSION: Our results suggest a considerable disparity between contemporary practice of management of new-onset AF in critical illness and treatment recommendations for the general patient population suffering from AF, particularly with regard to anti-arrhythmics and anti-coagulation used. Amongst intensivists, there is a substantial interest in research for management of new-onset AF in critically ill patients.

Hemodynamic actions of corticotropin-releasing hormone and proopiomelanocortin derivatives in septic patients.

Proopiomelanocortin (POMC) derivatives and mRNA of POMC have been detected in cardiomyocytes and vascular smooth muscle cells. Increased plasma levels of POMC derivatives have been found in septic patients during cardiovascular deregulation; therefore, we evaluated whether corticotroph-type (ACTH, ß-endorphin, ß-lipotropin) or melanotroph-type (α-melanocyte-stimulating hormone and N-acetyl-ß-END) POMC derivatives have influences on patients' hemodynamics during sepsis. Seventeen septic patients were monitored by pulmonary artery catheter and corticotropin-releasing hormone (CRH) tests were performed by intravenous administration of 100 µg CRH. Before, 15, 30, 45, and 60 minutes after CRH administration, hemodynamic variables were measured, and plasma concentrations of POMC derivatives were determined. After CRH administration, heart rate, cardiac index, and stroke index increased, and the systemic vascular resistance index decreased; moreover, a correlation between ACTH concentration and stroke index as well as an inverse correlation between (α-melanocyte-stimulating hormone concentration and systemic vascular resistance index was observed. CRH and ACTH may have opposite effects on the blood pressure (mean arterial pressure). Immediately after CRH injection mean arterial pressure decreased. ACTH (in contrast to ß-endorphin or ß-lipotropin), released into the cardiovascular compartment 15 minutes after CRH injection, might have raised mean arterial pressure as compatible with the correlation between ACTH levels and stroke index. (α-melanocyte-stimulating hormone appears to have a vasodilative effect during sepsis.

Indicators of erythrocyte damage after microwave warming of packed red blood cells.

BACKGROUND: Localized overheating of packed red blood cells (PRBCs) after microwave warming with consequent damage to erythrocytes has been reported. We therefore compared possible cellular markers of erythrocyte damage, as measured by flow cytometry, with laboratory indicators of hemolysis to evaluate the effects of microwave warming on PRBCs. METHODS: PRBC samples were warmed to room temperature or to 37, 42, 47, 52, or 57 degrees C in a water bath. Flow cytometry was performed after fluorescein labeling using antibodies to spectrin, Ca(2+)-ATPase, and Na(+)-K(+)-ATPase. The forward-to-sideward scatter (FSC/SSC) ratio and antibody binding were evaluated. Plasma free hemoglobin (FHb) and alpha-hydroxybutyrate dehydrogenase (HBDH) were measured immediately after heating and after 48 h. In addition, all measurements were made before and after the heating of PRBCs to 35 degrees C by a microwave blood warmer. RESULTS: Analysis of 15000 erythrocytes showed a decrease in the FSC/SSC ratio and antibody binding above 47 degrees C [at 37 degrees C, median (SD) of 94.2 (7.4) with 0.07 (0.05)% fluorescein-positive; at 52 degrees C, median (SD) of 177.0 (19.0) with 18.5 (6.4)% positively gated; P <0.001]. FHb [room temperature, 0.3 (0.2) g/L] was increased 2-fold at 37 and 42 degrees C, 4-fold at 47 degrees C, and 25-fold at 52 degrees C. HBDH increased in parallel. Hemolysis markers showed an additional twofold increase 48 h after heating to 42 and 47 degrees C. Microwave heating to 35 degrees C did not produce significant changes of any marker. CONCLUSIONS: All markers of cellular damage were altered after heating to >47 degrees C, and a substantial part of hemolysis was delayed. The methodology can be used for future testing of other blood warming devices.