Predictors and outcomes of withholding and withdrawal of life-sustaining treatments in intensive care units in Singapore: a multicentre observational study.

BACKGROUND: Clinical practice guidelines on limitation of life-sustaining treatments (LST) in the intensive care unit (ICU), in the form of withholding or withdrawal of LST, state that there is no ethical difference between the two. Such statements are not uniformly accepted worldwide, and there are few studies on LST limitation in Asia. This study aimed to evaluate the predictors and outcomes of withholding and withdrawal of LST in Singapore, focusing on the similarities and differences between the two approaches. METHODS: This was a multicentre observational study of patients admitted to 21 adult ICUs across 9 public hospitals in Singapore over an average of three months per year from 2014 to 2019. The primary outcome measures were withholding and withdrawal of LST (cardiopulmonary resuscitation, invasive mechanical ventilation, and vasopressors/inotropes). The secondary outcome measure was hospital mortality. Multivariable generalised mixed model analysis was used to identify independent predictors for withdrawal and withholding of LST and if LST limitation predicts hospital mortality. RESULTS: There were 8907 patients and 9723 admissions. Of the former, 80.8% had no limitation of LST, 13.0% had LST withheld, and 6.2% had LST withdrawn. Common independent predictors for withholding and withdrawal were increasing age, absence of chronic kidney dialysis, greater dependence in activities of daily living, cardiopulmonary resuscitation before ICU admission, higher Acute Physiology and Chronic Health Evaluation (APACHE) II score, and higher level of care in the first 24 h of ICU admission. Additional predictors for withholding included being of Chinese race, the religions of Hinduism and Islam, malignancy, and chronic liver failure. The additional predictor for withdrawal was lower hospital paying class (with greater government subsidy for hospital bills). Hospital mortality in patients without LST limitation, with LST withholding, and with LST withdrawal was 10.6%, 82.1%, and 91.8%, respectively (p < 0.001). Withholding (odds ratio 13.822, 95% confidence interval 9.987-19.132) and withdrawal (odds ratio 38.319, 95% confidence interval 24.351-60.298) were both found to be independent predictors of hospital mortality on multivariable analysis. CONCLUSIONS: Differences in the independent predictors of withholding and withdrawal of LST exist. Even after accounting for baseline characteristics, both withholding and withdrawal of LST independently predict hospital mortality. Later mortality in patients who had LST withdrawn compared to withholding suggests that the decision to withdraw may be at the point when medical futility is recognised.

Impact of structured curriculum with simulation on bronchoscopy.

BACKGROUND AND OBJECTIVE: Simulation enhances a physician's competency in procedural skills by accelerating ascent of the learning curve. Training programmes are moving away from the Halstedian model of 'see one, do one, teach one', also referred as medical apprenticeship. We aimed to determine if a 3-month structured bronchoscopy curriculum that incorporated simulator training could improve bronchoscopy competency among pulmonary medicine trainees. METHODS: We prospectively recruited trainees from hospitals with accredited pulmonary medicine programmes. Trainees from hospitals (A, B and C) were assigned to control group (CG) where they received training by traditional apprenticeship while trainees from hospital D were assigned to intervention group (IG) where they underwent 3-month structured curriculum that incorporated training with the bronchoscopy simulator. Two patient bronchoscopy procedures per trainee were recorded on video and scored independently by two expert bronchoscopists using the modified Bronchoscopy Skills and Tasks Assessment Tool (BSTAT) forms. A 25 multiple choice questions (MCQ) test was administered to all participants at the end of 3 months. RESULTS: Eighteen trainees participated; 10 in CG and eight in IG with equal female:male ratio. Competency assessed by modified BSTAT and MCQ tests was variable and not driven by volume as IG performed fewer patient bronchoscopies but demonstrated better BSTAT, airway anaesthesia and MCQ scores. Bronchoscopy simulator training was the only factor that correlated with better BSTAT (r = 0.80), MCQ (r = 0.85) and airway anaesthesia scores (r = 0.83), and accelerated the learning curve of IG trainees. CONCLUSION: An intensive 3-month structured bronchoscopy curriculum that incorporated simulator training led to improved cognitive and technical skill performance as compared with apprenticeship training.

Ensuring Sustainability of Continuous Kidney Replacement Therapy in the Face of Extraordinary Demand: Lessons From the COVID-19 Pandemic.

With the exponential surge in patients with coronavirus disease 2019 (COVID-19) worldwide, the resources needed to provide continuous kidney replacement therapy (CKRT) for patients with acute kidney injury or kidney failure may be threatened. This article summarizes subsisting strategies that can be implemented immediately. Pre-emptive weekly multicenter projections of CKRT demand based on evolving COVID-19 epidemiology and routine workload should be made. Corresponding consumables should be quantified and acquired, with diversification of sources from multiple vendors. Supply procurement should be stepped up accordingly so that a several-week stock is amassed, with administrative oversight to prevent disproportionate hoarding by institutions. Consumption of CKRT resources can be made more efficient by optimizing circuit anticoagulation to preserve filters, extending use of each vascular access, lowering blood flows to reduce citrate consumption, moderating the CKRT intensity to conserve fluids, or running accelerated KRT at higher clearance to treat more patients per machine. If logistically feasible, earlier transition to intermittent hemodialysis with online-generated dialysate, or urgent peritoneal dialysis in selected patients, may help reduce CKRT dependency. These measures, coupled to multicenter collaboration and a corresponding increase in trained medical and nursing staffing levels, may avoid downstream rationing of care and save lives during the peak of the pandemic.

Pneumonia in the tropics.

Pneumonia in the tropics poses a heavy disease burden. The complex interplay of climate change, human migration influences and socio-economic factors lead to changing patterns of respiratory infections in tropical climate but also increasingly in temperate countries. Tropical and poorer countries, especially South East Asia, also bear the brunt of the global tuberculosis (TB) pandemic, accounting for almost one-third of the burden. But, as human migration patterns evolve, we expect to see more TB cases in higher income as well as temperate countries, and rise in infections like scrub typhus from ecotourism activities. Fuelled by the ease of air travel, novel zoonotic infections originating from the tropics have led to global respiratory pandemics. As such, clinicians worldwide should be aware of these new conditions as well as classical tropical bacterial pneumonias such as melioidosis. Rarer entities such as co-infections of leptospirosis and chikungunya or dengue will need careful consideration as well. In this review, we highlight aetiologies of pneumonia seen more commonly in the tropics compared with temperate regions, their disease burden, variable clinical presentations as well as impact on healthcare delivery.

Frequency and prognostic impact of basic critical care echocardiography abnormalities in patients with acute respiratory distress syndrome.

BACKGROUND: Among intensive care unit (ICU) patients with acute respiratory distress syndrome (ARDS), apart from acute cor pulmonale (ACP), the frequency and prognostic impact of basic critical care echocardiography (BCCE) abnormalities are not well defined. METHODS: Observational study of patients with ARDS, admitted from September 2012 to May 2014, who underwent BCCE within 48 h of admission to a 20-bed medical ICU. We examined the association of two major BCCE-detected abnormalities (left ventricular ejection fraction < 40% and severe ACP) with ICU/hospital mortality and ICU/hospital length of stay. Multivariable models adjusted for age and illness severity. RESULTS: Of 234 patients with ARDS (age 62.3 ± 14.3 years; 88/37.6% female; APACHE II 26.8 ± 8.3; 26.5% ICU mortality; 32.1% hospital mortality), 94 (40.2%) had at least one major BCCE-detected abnormality. The more common major BCCE abnormality found was severe ACP (28.2%), followed by left ventricular ejection fraction < 40% (16.2%). On multivariate analysis, only severe ACP remained significantly associated with ICU/hospital mortality. Hospital mortality for mild, moderate and severe ARDS was 17.0, 27.9 and 50.0%, respectively (without severe ACP), and was 29.2, 48.3 and 53.8%, respectively (with severe ACP). CONCLUSIONS: BCCE abnormalities were common, but only severe ACP had prognostic significance in ARDS, identifying patients who are at increased risk of ICU and hospital mortality. The presence of severe ACP appears to upstage ARDS severity by one level.

Tracheobronchial tuberculosis: a clinical review.

Endobronchial tuberculosis (EBTB) is defined as tuberculous infection of the tracheobronchial tree. The exact pathogenesis is unclear, and it has a heterogenous clinical course. Its diagnosis requires the clinician to have a high index of suspicion based on clinical symptoms and radiological features. Computed tomography and bronchoscopy are useful tools in its evaluation. The goal of treatment is in the eradication of tuberculous bacilli with appropriate anti-tuberculous therapy. Use of corticosteroids is controversial for the prevention of tracheobronchial stenosis. Interventional bronchoscopy or surgical intervention is employed to restore airway patency once significant stenosis occurs.

The Use of Polymerase Chain Reaction Amplification for the Detection of Viruses and Bacteria in Severe Community-Acquired Pneumonia.

BACKGROUND: Pathogens are often not identified in severe community-acquired pneumonia (CAP), and the few studies using polymerase chain reaction (PCR) techniques for virus detection are from temperate countries. OBJECTIVE: This study assesses if PCR amplification improves virus and bacteria detection, and if viral infection contributes to mortality in severe CAP in a tropical setting, where respiratory pathogens have less well-defined seasonality. METHODS: In this cohort study of patients with severe CAP in an intensive care unit, endotracheal aspirates for intubated patients and nasopharyngeal swabs for non-intubated patients were sent for PCR amplification for respiratory viruses. Blood, endotracheal aspirates for intubated patients, and sputum for non-intubated patients were analysed using a multiplex PCR system for bacteria. RESULTS: Out of 100 patients, using predominantly cultures, bacteria were identified in 42 patients; PCR amplification increased this number to 55 patients. PCR amplification identified viruses in 32 patients. In total, only bacteria, only viruses, and both bacteria and viruses were found in 37, 14, and 18 patients, respectively. The commonest viruses were influenza A H1N1/2009 and rhinovirus; the commonest bacterium was Streptococcus pneumoniae. Hospital mortality rates for patients with no pathogens, bacterial infection, viral infection, and bacterial-viral co-infection were 16.1, 24.3, 0, and 5.6%, respectively (p = 0.10). On multivariable analysis, virus detection was associated with lower mortality (adjusted odds ratio 0.12, 95% confidence interval 0.2-0.99; p = 0.049). CONCLUSIONS: Viruses and bacteria were detected in 7 of 10 patients with severe CAP with the aid of PCR amplification. Viral infection appears to be independently associated with lower mortality.