Favorable outcomes of COVID-19 in vaccinated hematopoietic stem cell transplant recipients: A single-center experience.

INTRODUCTION: A high incidence of mortality and severe COVID-19 infection was reported in hematopoietic stem cell transplant (HSCT) recipients during the early phases of the COVID-19 pandemic; however, outcomes with subsequent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, such as the omicron variant, have yet to be reported. Additionally, rollout of COVID-19 vaccinations in subsequent pandemic waves may modify COVID-19 disease severity and mortality in this immunocompromised population. We describe COVID-19 outcomes among a highly vaccinated population of HSCT recipients at a single center during successive waves of community transmission arising from the SARS-CoV-2 delta and omicron variants. METHODS: We retrospectively reviewed medical records of all HSCT recipients at our institution who tested positive for SARS-CoV-2 from May 2021 to May 2022. Descriptive statistics were reported; the chi-square test was utilized to identify factors associated with 90-day all-cause mortality and severity of COVID-19 infection. RESULTS: Over the 1-year study period, 77 HSCT recipients at our center contracted COVID-19 (43 allogenic; 34 autologous). Twenty-six (33.8%) patients were infected with the SARS-CoV-2 delta variant, while 51 (66.2%) had the SARS-CoV-2 omicron variant. Thirty-nine (50.6%) patients required hospitalization. More than 80% had received prior COVID-19 vaccination (57.1% with two doses, 27.3% with three doses). The majority (90.9%) had mild disease; only one (1.3%) patient required mechanical ventilation. Active hematological disease at time of COVID-19 infection was associated with increased odds of mortality [odds ratio (OR) = 6.90, 95% confidence interval (CI) = 1.20-40]. The 90-day all-cause mortality was 7.8% (six patients). Infection with the omicron variant (vs. delta) was associated with less severe illness (OR = 0.05, 95% CI = 0.01-0.47) and decreased odds of mortality (OR = 0.08, 95% CI = 0.01-0.76). Being on immunosuppression (OR = 5.10, 95% CI = 1.10-23.60) and being unvaccinated at disease onset (OR = 14.76, 95% CI = 2.89-75.4) were associated with greater severity of COVID-19 infection. CONCLUSION: We observed favorable outcomes with COVID-19 infection in a cohort of vaccinated HSCT patients. The SARS-CoV-2 omicron variant was associated with both less severe illness and decreased odds of mortality. As COVID-19 moves toward endemicity, early access to treatment and encouraging vaccination uptake is crucial in mitigating the challenge of COVID-19 management among HSCT recipients. Surveillance and assessment of clinical outcomes with new SARS-CoV-2 variants also remains important in this immunocompromised population.

Mortality Trends of Oncology and Hematopoietic Stem Cell Transplant Patients Supported on Extracorporeal Membrane Oxygenation: A Systematic Review and Meta-Analysis.

BACKGROUND: There is an increasing frequency of oncology and hematopoietic stem cell transplant (HSCT) patients seen in the intensive care unit and requiring extracorporeal membrane oxygenation (ECMO), however, prognosis of this population over time is unclear. METHODS: MEDLINE, EMBASE, Cochrane and Web of Science were searched from earliest publication until April 10, 2020 for studies to determine the mortality trend over time in oncology and HSCT patients requiring ECMO. Primary outcome was hospital mortality. Random-effects meta-analysis model was used to obtain pooled estimates of mortality and 95% confidence intervals. A priori subgroup metanalysis compared adult versus pediatric, oncology versus HSCT, hematological malignancy versus solid tumor, allogeneic versus autologous HSCT, and veno-arterial versus veno-venous ECMO populations. Multivariable meta-regression was also performed for hospital mortality to account for year of study and HSCT population. RESULTS: 17 eligible observational studies (n = 1109 patients) were included. Overall pooled hospital mortality was 72% (95% CI: 65, 78). In the subgroup analysis, only HSCT was associated with a higher hospital mortality compared to oncology subgroup [84% (95% CI: 70, 93) vs. 66% (95% CI: 56, 74); P = 0.021]. Meta-regression showed that HSCT was associated with increased mortality [adjusted odds ratio (aOR) 3.84 (95% CI 1.77, 8.31)], however, mortality improved with time [aOR 0.92 (95% CI: 0.85, 0.99) with each advancing year]. CONCLUSION: This study reports a high overall hospital mortality in oncology and HSCT patients on ECMO which improved over time. The presence of HSCT portends almost a 4-fold increased risk of mortality and this finding may need to be taken into consideration during patient selection for ECMO.

Outcomes of second-tier rapid response activations in a tertiary referral hospital: A prospective observational study.

INTRODUCTION: A second-tier rapid response team (RRT) is activated for patients who do not respond to first-tier measures. The premise of a tiered response is that first-tier responses by a ward team may identify and correct early states of deterioration or establish goals of care, thereby reducing unnecessary escalation of care to the RRT. Currently, utilisation and outcomes of tiered RRTs remain poorly described. METHODS: A prospective observational study of adult patients (age ≥18 years) who required RRT activations was conducted from February 2018 to December 2019. RESULTS: There were 951 consecutive RRT activations from 869 patients and 76.0% patients had a National Early Warning Score (NEWS) ≥5 at the time of RRT activation. The majority (79.8%) of patients required RRT interventions that included endotracheal intubation (12.7%), point-of-care ultrasound (17.0%), discussing goals of care (14.7%) and intensive care unit (ICU) admission (24.2%). Approximately 1 in 3 (36.6%) patients died during hospitalisation or within 30 days of RRT activation. In multivariate analysis, age ≥65 years, NEWS ≥7, ICU admission, longer hospitalisation days at RRT activation, Eastern Cooperative Oncology Group performance scores ≥3 (OR [odds ratio] 2.24, 95% CI [confidence interval] 1.45-3.46), metastatic cancer (OR 2.64, 95% CI 1.71-4.08) and haematological cancer (OR 2.78, 95% CI 1.84-4.19) were independently associated with mortality. CONCLUSION: Critical care interventions and escalation of care are common with second-tier RRTs. This supports the need for dedicated teams with specialised critical care services. Poor functional status, metastatic and haematological cancer are significantly associated with mortality, independent of age, NEWS and ICU admission. These factors should be considered during triage and goals of care discussion.

Factors to Consider in the Use of Vital Signs Wearables to Minimize Contact With Stable COVID-19 Patients: Experience of Its Implementation During the Pandemic.

The COVID-19 pandemic has created a huge burden on the healthcare industry worldwide. Pressures to increase the isolation healthcare facility to cope with the growing number of patients led to an exploration of the use of wearables for vital signs monitoring among stable COVID-19 patients. Vital signs wearables were chosen for use in our facility with the purpose of reducing patient contact and preserving personal protective equipment. The process of deciding on the wearable solution as well as the implementation of the solution brought much insight to the team. This paper presents an overview of factors to consider in implementing a vital signs wearable solution. This includes considerations before deciding on whether or not to use a wearable device, followed by key criteria of the solution to assess. With the use of wearables rising in popularity, this serves as a guide for others who may want to implement it in their institutions.

Integrative Profiling of T790M-Negative EGFR-Mutated NSCLC Reveals Pervasive Lineage Transition and Therapeutic Opportunities.

PURPOSE: Despite the established role of EGFR tyrosine kinase inhibitors (TKIs) in EGFR-mutated NSCLC, drug resistance inevitably ensues, with a paucity of treatment options especially in EGFR T790M-negative resistance. EXPERIMENTAL DESIGN: We performed whole-exome and transcriptome analysis of 59 patients with first- and second-generation EGFR TKI-resistant metastatic EGFR-mutated NSCLC to characterize and compare molecular alterations mediating resistance in T790M-positive (T790M+) and -negative (T790M-) disease. RESULTS: Transcriptomic analysis revealed ubiquitous loss of adenocarcinoma lineage gene expression in T790M- tumors, orthogonally validated using multiplex IHC. There was enrichment of genomic features such as TP53 alterations, 3q chromosomal amplifications, whole-genome doubling and nonaging mutational signatures in T790M- tumors. Almost half of resistant tumors were further classified as immunehot, with clinical outcomes conditional on immune cell-infiltration state and T790M status. Finally, using a Bayesian statistical approach, we explored how T790M- and T790M+ disease might be predicted using comprehensive genomic and transcriptomic profiles of treatment-naïve patients. CONCLUSIONS: Our results illustrate the interplay between genetic alterations, cell lineage plasticity, and immune microenvironment in shaping divergent TKI resistance and outcome trajectories in EGFR-mutated NSCLC. Genomic and transcriptomic profiling may facilitate the design of bespoke therapeutic approaches tailored to a tumor's adaptive potential.

Low incidence of venous thrombosis but high incidence of arterial thrombotic complications among critically ill COVID-19 patients in Singapore.

BACKGROUND: Arterial and venous thrombosis are reported to be common in critically ill COVID-19 patients. METHOD AND RESULTS: This is a national multicenter retrospective observational study involving all consecutive adult COVID-19 patients who required intensive care units (ICU) admission between 23 January 2020 and 30 April 2020 in Singapore. One hundred eleven patients were included and the venous and arterial thrombotic rates in ICU were 1.8% (n = 2) and 9.9% (n = 11), respectively. Major bleeding rate was 14.8% (n = 16). CONCLUSIONS: Critically ill COVID-19 patients in Singapore have lower venous thromboembolism but higher arterial thrombosis rates and bleeding manifestations than other reported cohorts.

Description of parallel and sequential configurations for concurrent therapeutic plasma exchange and continuous kidney replacement therapy in adults.

Therapeutic plasma exchange (TPE) and continuous kidney replacement therapy (CKRT) are extracorporeal therapeutic procedures often implemented in management of patients. Critically ill patients may be afflicted with disease processes that require both TPE and CKRT. Performing TPE discontinuous with CKRT is technically easier, however, it disrupts CKRT and may compromise with CKRT efficiency or hemofilter life. Concurrent TPE with CKRT offers several advantages including simultaneous control of disease process and correction of electrolyte, fluid, and acid-base disturbances that may accompany TPE. Additionally, TPE may be performed by either centrifugation method or membrane plasma separation method. The technical specifications of these methods may influence the methodology of concurrent connections. This report describes and reviews two different approaches to circuit arrangements when establishing concurrent TPE and CKRT.

Waitlisted Transplant Candidates' Attitudes and Concerns Toward Transplantation During COVID-19.

BACKGROUND In solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients, coronavirus disease 2019 (COVID-19) can contribute to a severe clinical course and an increased risk of death. Thus, patients awaiting a SOT or HSCT face the dilemma of choosing between a life-saving treatment that presents a significant threat of COVID-19 and the risk of waitlist dropout, progression of disease, or mortality. The lack of established literature on COVID-19 complicates the issue as patients, particularly those with inadequate health literacy, may not have the resources needed to navigate these decisions. MATERIAL AND METHODS We conducted a standardized phone survey of patients awaiting SOT or HSCT to assess the prevalence of inadequate health literacy and attitudes toward transplant during the COVID-19 pandemic. RESULTS Seventy-one patients completed the survey, with a response rate of 84.5%. Regardless of health literacy, most waitlisted candidates recognized that the current pandemic is a serious situation affecting their care and that COVID-19 poses a significant risk to their health. Despite the increased risks, most patients reported they would choose immediate transplantation if there was no foreseeable end to the pandemic, and especially if the medical urgency did not permit further delay. There were no differences in responses across the patient waitlist groups for heart, kidney, liver, and stem cell transplant. CONCLUSIONS These findings can help transplant centers decide how transplantation services should proceed during this pandemic and can be used to educate patients and guide discussions about informed consent for transplant during the COVID-19 pandemic.

Impact of an Extracorporeal Membrane Oxygenation Intensivist-Led Multidisciplinary Team on Venovenous Extracorporeal Membrane Oxygenation Outcomes.

OBJECTIVES: Venovenous extracorporeal membrane oxygenation is increasingly being established as a treatment option for severe acute respiratory failure. We sought to evaluate the impact of a dedicated specialist team-based approach on patient outcomes. DESIGN: Retrospective cohort study. SETTING: Single-center medical ICU in an academic tertiary hospital. PATIENTS: Adult patients initiated on venovenous extracorporeal membrane oxygenation for severe acute respiratory failure. INTERVENTIONS: Initiation of an extracorporeal membrane oxygenation intensivist-led multidisciplinary team; critical decisions on extracorporeal membrane oxygenation management were jointly made by a dedicated team of extracorporeal membrane oxygenation intensivists, together with the multidisciplinary team. MEASUREMENTS AND MAIN RESULTS: Eighty-one patients (75%) and 27 patients (35%) were initiated on venovenous extracorporeal membrane oxygenation in the preextracorporeal membrane oxygenation intensivist-led multidisciplinary team (before January 2018) and postextracorporeal membrane oxygenation intensivist-led multidisciplinary team period (after January 2018), respectively. Inhospital (14.8% vs 44.4%, p = 0.006) and ICU mortality (11.1% vs 40.7%, p = 0.005) were significantly lower in the postextracorporeal membrane oxygenation intensivist-led multidisciplinary team period. On multivariate analysis correcting for possible confounding factors (ICU severity and extracorporeal membrane oxygenation-specific mortality prediction scores, body mass index, preextracorporeal membrane oxygenation vasopressor support, preextracorporeal membrane oxygenation cardiac arrest, and days on mechanical ventilation before extracorporeal membrane oxygenation initiation), management by an extracorporeal membrane oxygenation intensivist-led multidisciplinary team remained associated with improved hospital survival (odds ratio, 5.06; 95% CI, 1.20-21.28). Patients in the postextracorporeal membrane oxygenation intensivist-led multidisciplinary team period had less nosocomial infections (18.5% vs 46.9%, p = 0.009), a shorter ICU stay (12 days [interquartile range, 6-16 d] vs 15 days [interquartile range, 10-24 d]; p = 0.049), and none suffered an intracranial hemorrhage or nonhemorrhagic stroke. CONCLUSIONS: An extracorporeal membrane oxygenation intensivist-led multidisciplinary team approach is associated with improved outcomes in patients initiated on venovenous extracorporeal membrane oxygenation for severe acute respiratory failure.

The Interplay Between Coagulation and Inflammation Pathways in COVID-19-Associated Respiratory Failure: A Narrative Review.

The novel coronavirus disease (COVID-19) pandemic has caused an unprecedented worldwide socio-economic and health impact. There is increasing evidence that a combination of inflammation and hypercoagulable state are the main mechanisms of respiratory failure in these patients. This narrative review aims to summarize currently available evidence on the complex interplay of immune dysregulation, hypercoagulability, and thrombosis in the pathogenesis of respiratory failure in COVID-19 disease. In addition, we will describe the experience of anticoagulation and anti-inflammatory strategies that have been tested. Profound suppression of the adaptive and hyperactivity of innate immune systems with macrophage activation appears to be a prominent feature in this infection. Immune dysregulation together with endotheliitis and severe hypercoagulability results in thromboinflammation and microvascular thrombosis in the pulmonary vasculature leading to severe respiratory distress. Currently, some guidelines recommend the use of prophylactic low molecular weight heparin in all hospitalized patients, with intermediate dose prophylaxis in those needing intensive care, and the use of therapeutic anticoagulation in patients with proven or suspected thrombosis. Strong recommendations cannot be made until this approach is validated by trial results. To target the inflammatory cascade, low-dose dexamethasone appears to be helpful in moderate to severe cases and trials with anti-interleukin agents (e.g., tocilizumab, anakinra, siltuximab) and non-steroidal anti-inflammatory drugs are showing early promising results. Potential newer agents (e.g., Janus kinase inhibitor such as ruxolitinib, baricitinib, fedratinib) are likely to be investigated in clinical trials. Unfortunately, current trials are mostly examining these agents in isolation and there may be a significant delay before evidence-based practice can be implemented. It is plausible that a combination of anti-viral drugs together with anti-inflammatory and anti-coagulation medicines will be the most successful strategy in managing severely affected patients with COVID-19.

Operationalization of critical care triage during a pandemic surge using protocolized communication and integrated supportive care.

Triage becomes necessary when demand for intensive care unit (ICU) resources exceeds supply. Without triage, there is a risk that patients will be admitted to the ICU in the sequence that they present, disadvantaging those who either present later or have poorer access to healthcare. Moreover, if the patients with the best prognosis are not allocated life support, there is the possibility that overall mortality will increase. Before formulating criteria, principles such as maximizing lives saved and fairness ought to have been agreed upon to guide decision-making. The triage process is subdivided into three parts, i.e., having explicit inclusion/exclusion criteria for ICU admission, prioritization of patients for allocation to available beds, and periodic reassessment of all patients already admitted to the ICU. Multi-dimensional criteria offer more holistic prognostication than only using age cutoffs. Appointed triage officers should also be enabled to make data-driven decisions. However, the process does not merely end with an allocation decision being made. Any decision has to be sensitively and transparently communicated to the patient and family. With infection control measures, there are challenges in managing communication and the psychosocial distress of dying alone. Therefore, explicit video call protocols and social services expertise will be necessary to mitigate these challenges. Besides symptom management and psychosocial management, supportive care teams play an integral role in coordination of complex cases. This scoping review found support for the three-pronged, triage-communication-supportive care approach to facilitate the smooth operationalization of the triage process in a pandemic.

Practical Considerations for Solid Organ Transplantation During the COVID-19 Global Outbreak: The Experience from Singapore.

The current coronavirus disease 2019 (COVID-19) pandemic has not only caused global social disruptions but has also put tremendous strain on healthcare systems worldwide. With all attention and significant effort diverted to containing and managing the COVID-19 outbreak (and understandably so), essential medical services such as transplant services are likely to be affected. Closure of transplant programs in an outbreak caused by a highly transmissible novel pathogen may be inevitable owing to patient safety. Yet program closure is not without harm; patients on the transplant waitlist may die before the program reopens. By adopting a tiered approach based on outbreak disease alert levels, and having hospital guidelines based on the best available evidence, life-saving transplants can still be safely performed. We performed a lung transplant and a liver transplant successfully during the COVID-19 era. We present our guidelines and experience on managing the transplant service as well as the selection and management of donors and recipients. We also discuss clinical dilemmas in the management COVID-19 in the posttransplant recipient.

Potential role of statins in COVID-19.

Patients with COVID-19 infection have an increased risk of cardiovascular complications and thrombotic events. Statins are known for their pleiotropic anti-inflammatory, antithrombotic and immunomodulatory effects. They may have a potential role as adjunctive therapy to mitigate endothelial dysfunction and dysregulated inflammation in patients with COVID-19 infection.

Early prediction of high flow nasal cannula therapy outcomes using a modified ROX index incorporating heart rate.

BACKGROUND: The ROX index (ratio of pulse oximetry/FIO2 to respiratory rate) has been validated to predict high flow nasal cannula therapy (HFNC) outcomes in patients with pneumonia. We evaluated a modified ROX index incorporating heart rate (HR) in patients initiated on HFNC for acute hypoxemic respiratory failure and as a preventative treatment following planned extubation. METHODS: We performed a prospective observational cohort study of 145 patients treated with HFNC. ROX-HR index was defined as the ratio of ROX index over HR (beats/min), multiplied by a factor of 100. Evaluation was performed using area under the receiving operating characteristic curve (AUROC) and cutoffs assessed for prediction of HFNC failure: defined as the need for mechanical ventilation. RESULTS: Ninety-nine (68.3%) and 46 (31.7%) patients were initiated on HFNC for acute hypoxemic respiratory failure and following a planned extubation, respectively. The majority (86.9%) of patients had pneumonia as a primary diagnosis, and 85 (56.6%) patients were immunocompromised. Sixty-one (42.1%) patients required intubation (HFNC failure). Amongst patients on HFNC for acute respiratory failure, HFNC failure was associated with a lower ROX and ROX-HR index recorded at time points between 1 and 48 h. Within the first 12 h, both indices performed with the highest AUROC at 10 h as follows: 0.723 (95% CI 0.605-0.840) and 0.739 (95% CI 0.626-0.853) for the ROX and ROX-HR index respectively. A ROX-HR index of > 6.80 was significantly associated with a lower risk of HFNC failure (hazard ratio 0.301 (95% CI 0.143-0.663)) at 10 h. This association was also observed at 2, 6, 18, and 24h, even with correction for potential confounding factors. For HFNC initiated post-extubation, only the ROX-HR index remained significantly associated with HFNC failure at all recorded time points between 1 and 24 h. A ROX-HR > 8.00 at 10 h was significantly associated with a lower risk of HFNC failure (hazard ratio 0.176 (95% CI 0.051-0.604)). CONCLUSION: While validation studies are required, the ROX-HR index appears to be a promising tool for early identification of treatment failure in patients initiated on HFNC for acute hypoxemic respiratory failure or as a preventative treatment after a planned extubation.

Clinical Updates on the Diagnosis and Management of Chronic Thromboembolic Pulmonary Hypertension.

INTRODUCTION: Chronic thromboembolic pulmonary hypertension (CTEPH) is a known sequela after acute pulmonary embolism (PE). It is a debilitating disease, and potentially fatal if left untreated. This review provides a clinically relevant overview of the disease and discusses the usefulness and limitations of the various investigational and treatment options. METHODS: A PubMed search on articles relevant to PE, pulmonary hypertension, CTEPH, pulmonary endarterectomy, and balloon pulmonary angioplasty were performed. A total of 68 articles were found to be relevant and were reviewed. RESULTS: CTEPH occurs as a result of non-resolution of thrombotic material, with subsequent fibrosis and scarring of the pulmonary arteries. Risk factors have been identified, but the underlying mechanisms have yet to be fully elucidated. The cardinal symptom of CTEPH is dyspnoea on exertion, but the diagnosis is often challenging due to lack of awareness. The ventilation/perfusion scan is recommended for screening for CTEPH, with other modalities (eg. dual energy computed tomography pulmonary angiography) also being utilised in expert centres. Conventional pulmonary angiography with right heart catheterisation is important in the final diagnosis of CTEPH. CONCLUSION: Operability assessment by a multidisciplinary team is crucial for the management of CTEPH, as pulmonary endarterectomy (PEA) remains the guideline recommended treatment and has the best chance of cure. For inoperable patients or those with residual disease post-PEA, medical therapy or balloon pulmonary angioplasty are potential treatment options.

Preparing your intensive care unit for the COVID-19 pandemic: practical considerations and strategies.

The coronavirus disease 2019 (COVID-19) has rapidly evolved into a worldwide pandemic. Preparing intensive care units (ICU) is an integral part of any pandemic response. In this review, we discuss the key principles and strategies for ICU preparedness. We also describe our initial outbreak measures and share some of the challenges faced. To achieve sustainable ICU services, we propose the need to 1) prepare and implement rapid identification and isolation protocols, and a surge in ICU bed capacity; (2) provide a sustainable workforce with a focus on infection control; (3) ensure adequate supplies to equip ICUs and protect healthcare workers; and (4) maintain quality clinical management, as well as effective communication.