Contact tracing using real-time location system (RTLS): a simulation exercise in a tertiary hospital in Singapore.

OBJECTIVE: We aim to assess the effectiveness of contact tracing using real-time location system (RTLS) compared with the conventional (electronic medical records (EMRs)) method via an emerging infectious disease (EID) outbreak simulation exercise. The aims of the study are: (1) to compare the time taken to perform contact tracing and list of contacts identified for RTLS versus EMR; (2) to compare manpower and manpower-hours required to perform contact tracing for RTLS versus EMR; and (3) to extrapolate the cost incurred by RTLS versus EMR. DESIGN: Prospective case study. SETTING: Sengkang General Hospital, a 1000-bedded public tertiary hospital in Singapore. PARTICIPANTS: 1000 out of 4000 staff wore staff tags in this study. INTERVENTIONS: A simulation exercise to determine and compare the list of contacts, time taken, manpower and manpower-hours required between RTLS and conventional methods of contact tracing. Cost of both methods were compared. PRIMARY AND SECONDARY OUTCOME MEASURES: List of contacts, time taken, manpower required, manpower-hours required and cost incurred. RESULTS: RTLS identified almost three times the number of contacts compared with conventional methods, while achieving that with a 96.2% reduction in time taken, 97.6% reduction in manpower required and 97.5% reduction in manpower-hours required. However, RTLS incurred significant equipment cost and might take many contact tracing episodes before providing economic benefit. CONCLUSION: Although costly, RTLS is effective in contact tracing. RLTS might not be ready at present time to replace conventional methods, but with further refinement, RTLS has the potential to be the gold standard in contact tracing methods of the future, particularly in the current pandemic.

High frequency of anti-DSG 2 antibodies in post COVID-19 serum samples.

BACKGROUND: There is growing recognition that COVID-19 does cause cardiac sequelae. The underlying mechanisms involved are still poorly understood to date. Viral infections, including COVID-19, have been hypothesized to contribute to autoimmunity, by exposing previously hidden cryptic epitopes on damaged cells to an activated immune system. Given the high incidence of cardiac involvement seen in COVID-19, our aim was to determine the frequency of anti-DSG2 antibodies in a population of post COVID-19 patients. METHODS AND RESULTS: 300 convalescent serum samples were obtained from a group of post COVID-19 infected patients from October 2020 to February 2021. 154 samples were drawn 6 months post-COVID-19 infection and 146 samples were drawn 9 months post COVID infection. 17 samples were obtained from the same patient at the 6- and 9- month mark. An electrochemiluminescent-based immunoassay utilizing the extracellular domain of DSG2 for antibody capture was used. The mean signal intensity of anti-DSG2 antibodies in the post COVID-19 samples was significantly higher than that of a healthy control population (19 ± 83.2 in the post-COVID-19 sample vs. 2.1 ± 7.2 (p < 0. 0001) in the negative control healthy population). Of note, 29.3% of the post COVID-19 infection samples demonstrated a signal higher than the 90th percentile of the control population and 8.7% were higher than the median found in ARVC patients. The signal intensity between the 6-month and 9-month samples did not differ significantly. CONCLUSIONS: We report for the first time that recovered COVID-19 patients demonstrate significantly higher and sustained levels of anti-DSG2 autoantibodies as compared to a healthy control population, comparable to that of a diagnosed ARVC group.

Widely heterogeneous humoral and cellular immunity after mild SARS-CoV-2 infection in a homogeneous population of healthy young men.

BACKGROUND: We studied humoral and cellular responses against SARS-CoV-2 longitudinally in a homogeneous population of healthy young/middle-aged men of South Asian ethnicity with mild COVID-19. METHODS: In total, we recruited 994 men (median age: 34 years) post-COVID-19 diagnosis. Repeated cross-sectional surveys were conducted between May 2020 and January 2021 at six time points - day 28 (n = 327), day 80 (n = 202), day 105 (n = 294), day 140 (n = 172), day 180 (n = 758), and day 280 (n = 311). Three commercial assays were used to detect anti-nucleoprotein (NP) and neutralizing antibodies. T cell response specific for Spike, Membrane and NP SARS-CoV-2 proteins was tested in 85 patients at day 105, 180, and 280. RESULTS: All serological tests displayed different kinetics of progressive antibody reduction while the frequency of T cells specific for different structural SARS-CoV-2 proteins was stable over time. Both showed a marked heterogeneity of magnitude among the studied cohort. Comparatively, cellular responses lasted longer than humoral responses and were still detectable nine months after infection in the individuals who lost antibody detection. Correlation between T cell frequencies and all antibodies was lost over time. CONCLUSION: Humoral and cellular immunity against SARS-CoV-2 is induced with differing kinetics of persistence in those with mild disease. The magnitude of T cells and antibodies is highly heterogeneous in a homogeneous study population. These observations have implications for COVID-19 surveillance, vaccination strategies, and post-pandemic planning.

Factors influencing SARS-CoV-2 transmission and outbreak control measures in densely populated settings.

Starting with a handful of SARS-CoV-2 infections in dormitory residents in late March 2020, rapid transmission in their dense living environments ensued and by October 2020, more than 50,000 acute infections were identified across various dormitories in Singapore. The aim of the study is to identify combination of factors facilitating SARS-CoV-2 transmission and the impact of control measures in a dormitory through extensive epidemiological, serological and phylogenetic investigations, supported by simulation models. Our findings showed that asymptomatic cases and symptomatic cases who did not seek medical attention were major drivers of the outbreak. Furthermore, each resident had about 30 close contacts and each infected resident spread to 4.4 (IQR 3.5-5.3) others at the start of the outbreak. The final attack rate of the current outbreak was 76.2% (IQR 70.6-98.0%) and could be reduced by further 10% under a modified dormitory housing condition. These findings are important when designing living environments in a post COVID-19 future to reduce disease spread and facilitate rapid implementation of outbreak control measures.

Challenges and opportunities in pragmatic implementation of a holistic hospital care model in Singapore: A mixed-method case study.

INTRODUCTION: Hospital-based practices today remain predominantly disease-oriented, focusing on individual clinical specialties with less visibility on a comprehensive picture of each patient's health needs. To tackle the challenge of growing multimorbidity worldwide, practices without disease-specific focus have shown better integration of services. However, as we move away from the familiar disease-specific approaches of care delivery, many of us are still learning how to implement generalist care in a cost-effective manner. METHODS: This mixed-method case study, which centred on a specialist-led General Medicine model implemented at an acute hospital in Singapore, aimed to (1) quantitatively summarise its clinical outcomes, and (2) qualitatively describe the challenges and lessons gathered from the pragmatic implementation of the care model. Quantitative hospital data were extracted from databases and summarised. Qualitative staff-reported experiences and insights were gathered through semi-structured interviews and analysed using thematic analysis. RESULTS: Quantitative findings revealed that the generalist care model was implemented with high fidelity, where more than 75% of patients admitted were placed under General Medicine's or General Surgery's care. The mean length of stay was 2.6 days, and the 30-day post-discharge readmission rate was 15%. Inpatient mortality rate was found to be 2.8%, and the average gross hospitalisation bill amounted to SGD3,085.30. For qualitative findings, themes concerning feasibility and operational aspects of the implementation were grouped into categories- (1) Feasibility of 'One Care Team' approach, (2) Enablers required for meaningful generalist care, (3) Challenges surrounding information sharing, (4) Lack of integration with the community to facilitate care transition, and (5) Evolving roles of self-management. The findings were rich, with some being identified as barriers that could benefit from system-level de-constraining. DISCUSSION: This case study was an illustration of our pursuit for an integrated solution to rising prevalence of multimorbidity. While quantitative findings indicated that a pivot towards General Medicine might be possible, data also revealed gaps in clinical outcomes, especially in readmission rates. These findings corroborated with much of the lessons and challenges gathered from qualitative interviews, specifically surrounding the lack of receptacles in the community to facilitate care transition, training, and competency of generalists in holistic management of complex multimorbid cases, as well as inadequate infrastructure to allow information sharing between providers. Thus, a multi-pronged approach might be required to develop a new and sustainable care model for patients with multimorbidity in the long run. In the short to medium transitional period, nonetheless, the specialist-led General Medicine care model demonstrated might be a viable interim approach, especially in circumstances where trained medical generalists remained limited.

COVID-19 not detected in peritoneal fluid: a case of laparoscopic appendicectomy for acute appendicitis in a COVID-19-infected patient.

PURPOSE: COVID-19 greatly affected millions and affected the way we practice with heightened posture in the way we treat surgical patients. Surgical consensus guidelines are recommending caution in the use of laparoscopy for the theoretical possibility of viral transmission from aerosolization of tissue and peritoneal fluid during surgery. However, there has yet to be proof of COVID-19 being present in peritoneal fluid, justifying the consensus statements. We aim to assess the presence of COVID-19 in peritoneal fluid. METHODS: We performed a laparoscopic appendicectomy for a COVID-19-infected patient with acute appendicitis. Peritoneal fluid and peritoneal washings were collected and sent for COVID-19 PCR. RESULTS: The peritoneal fluid sample collected on entry and at the end of the operation was negative for COVID-19 on PCR. The patient had an uneventful recovery from surgery. CONCLUSIONS: This case revealed that COVID-19 was not detected in peritoneal fluid and peritoneal washings in a patient infected with COVID-19. This study provides novel preliminary data in the investigation of COVID-19 transmission from laparoscopy-related aerosolization.

Prevalence of preoperative anemia, abnormal mean corpuscular volume and red cell distribution width among surgical patients in Singapore, and their influence on one year mortality.

INTRODUCTION: Preoperative anemia and high red cell distribution width (RDW) are associated with higher perioperative mortality. Conditions with high RDW levels can be categorized by mean corpuscular volume (MCV). The relationship between RDW, anemia and MCV may explain causality between high RDW levels and outcomes. We aim to establish the prevalence of preoperative anemia and distribution of RDW and MCV among pre-surgical patients in Singapore. In addition, we aim to investigate the association between preoperative anemia, RDW and MCV levels with one-year mortality after surgery. METHODS: Retrospective review of 97,443 patients aged > = 18 years who underwent cardiac and non-cardiac surgeries under anesthesia between January 2012 and October 2016. Patient demographics, comorbidities, priority of surgery, surgical risk classification, perioperative transfusion, preoperative hemoglobin, RDW, MCV were collected. WHO anemia classification was used. High RDW was defined as >15.7%. Multivariate regression analyses were done to identify independent risk factors for mild or moderate/severe anemia and high RDW (>15.7). Multivariate cox regression analysis was done to determine the effect of preoperative anemia, abnormal RDW and MCV values on 1-year mortality. RESULTS: Our cohort comprised of 94.7% non-cardiac and 5.3% cardiac surgeries. 88.7% of patients achieved 1 year follow-up. Anemia prevalence was 27.8%-mild anemia 15.3%, moderate anemia 12.0% and severe anemia 0.5%. One-year mortality was 3.5%. Anemia increased with age in males, while in females, anemia was more prevalent between 18-49 years and > = 70 years. Most anemics were normocytic. Normocytosis and macrocytosis increased with age, while microcytosis decreased with age. Older age, male gender, higher ASA-PS score, anemia (mild- aHR 1.98; moderate/severe aHR 2.86), macrocytosis (aHR 1.47), high RDW (aHR 2.34), moderate-high risk surgery and emergency surgery were associated with higher hazard ratios of one-year mortality. DISCUSSION: Preoperative anemia is common. Anemia, macrocytosis and high RDW increases one year mortality.

[Standardized management of acupuncture-moxibustion clinic in Singapore General Hospital].

The standardized management of acupuncture-moxibustion in Singapore General Hospital is introduced. With gradual improvement of outpatient infrastructure, re-training of medical staff, strict disinfection of manipulation, periodical inspection of medical instruments, unified management of writing, saving and processing in medical records and public education of TCM knowledge, a standardized management system in accordance with modernized hospital is gradually established. As a result, efficiency and quality of clinical treatment is continuously increasing. From April of 1998 to December of 2012, a total of 74 654 times of treatment were performed, and treatment amount per day is gradually increased. The unusual condition of acupuncture is avoided. Periodical strict inspection of joint committee authenticated by domestic and overseas medical health organization is repeatedly passed and accepted. Additionally, three clinical researches funded by Singapore Health-care Company are still in progress in acupuncture-moxibustion department.

Risk factors for lower extremity amputation among patients with diabetes in Singapore.

BACKGROUND: Among other risk factors, renal disease and ethnicity have been associated with diabetic lower extremity amputation (LEA) in Western populations. However, little is known about risk factors for LEA among Asian patients. OBJECTIVE: The objective was to assess the proportion of hospitalized patients with diabetes who have a LEA among all hospital patients with diabetes mellitus (DM) and to investigate risk factors for diabetic LEA (especially renal disease and ethnicity) using hospital discharge database. METHOD: A retrospective study of hospital discharge database (2004-2009) was performed to identify patients with DM, LEA and renal disease using the International Statistical Classification of Diseases and Related Health Problems, Ninth Revision, Australian Modification codes. RESULTS: Of 44 917 hospitalized patients with DM during the 6 years, 7312 (16.3%) patients had renal disease, and 1457 (3.2%) patients had LEA. DM patients with renal disease had significant higher rates of LEA (7.1%) compared to DM patients without renal disease (2.5%, P < .001). The differences were present for foot (2.7% vs. 1.2%), ankle or leg (2.8% vs. 0.9%), and knee or above amputation (1.6% vs. 0.4%, all P<.001). Malays had the highest rate of diabetic LEA (5.1%), followed by Indians (3.0%), Chinese (3.0%), and others (2.3%, P < .001). In logistic regression analyses, renal disease and ethnicity were significant predictors of diabetic LEA (renal disease: odds ratio 3.2, 95% confidence interval 2.8-3.6; ethnicity: odds ratio, 1.6, Malays vs. Chinese, P < .001; 1.0, Indians vs. Chinese, P = .784) after adjustment for age, gender, and year of discharge. CONCLUSION: DM patients with renal disease and Malay ethnicity had higher rates of LEA in this Asian patient population. Malay patients with DM and diabetic patients with renal disease should be considered as high-risk groups for LEA and therefore screened and monitored systematically.

Respiratory dysfunction in patients with sepsis: protective effect of diabetes mellitus.

BACKGROUND: Sepsis is a common complication in patients with diabetes mellitus. In a Western population, risk of respiratory dysfunction was lower in diabetic patients with sepsis. OBJECTIVE: To compare organ dysfunction, particularly respiratory dysfunction, between sepsis patients with and without diabetes mellitus in an Asian population. METHOD: Hospital discharge data were collected for the period 2004 through 2008. Patients with sepsis, diabetes mellitus, and organ dysfunction were identified by using the International Statistical Classification of Diseases and Related Health Problems, 9th Revision, Australian Modification codes. RESULTS: Of the 383 238 patients hospitalized during the 5 years, 2943 of the 9221 who had sepsis also had diabetes (31.9%).The most common organ dysfunctions in patients with sepsis were renal (31.5%), cardiovascular (19.2%), and respiratory (10.9%). Among patients with sepsis, respiratory dysfunction was less likely in patients with diabetes (9.4%) than in those without (11.6%; P = .002), but renal dysfunction was more likely in patients with diabetes (46.5%) than in those without (24.4%; P < .001). However, only 27.6% of patients with diabetes had a respiratory source of sepsis compared with 33.4% in patients without diabetes (P < .001). Among patients with sepsis, diabetes mellitus was a significant and independent predictor of respiratory dysfunction (odds ratio, 0.80; 95% confidence interval, 0.66-0.98) after adjustments for age, sex, ethnicity, admission to intensive care, number of comorbid conditions, and other infection sources. CONCLUSION: Among an Asian population, respiratory dysfunction in patients with sepsis is less likely to develop in those with diabetes than in those without diabetes.

The effect of comorbidity and age on hospital mortality and length of stay in patients with sepsis.

PURPOSE: Sepsis is believed to be responsible for substantial health care burden, but there is limited information about its magnitude and the factors affecting health outcomes in Asian population. The aim of the study was to assess the disease burden of sepsis and to test the usefulness of Charlson Comorbidity Index (CCI) and age as risk-adjusted hospital mortality predictors in patients with sepsis using hospital administrative database. METHODS: A retrospective cohort study of hospital discharge database from 2004 to 2007 to identify cases with sepsis, comorbidity, and organ failure using the International Statistical Classification of Diseases and Related Health Problems, 9th Revision, Australian Modification codes was conducted. RESULTS: Of 305,637 hospitalized patients over 4 years, 6929 (2.27%) patients had sepsis, with 1216 (17.5%) patients associated with intensive care unit (ICU) admission. The mortality rates increased consistently in patients with CCI ranging from none to low, moderate and high grade for both patients with ICU admission (39.4%, 51.6%, 55.9%, and 54.3% respectively; P < .001) and patients without ICU admission (6.4%, 8.7%, 17.1%, and 25.3% respectively; P < .001). Logistic regression analysis showed that CCI (odds ratio, 11.8; high versus none) and age (odds ratio, 8.46; aged 85 years and older versus aged 18-54 years old) were significant and independent predictors of hospital mortality. Similar results were seen with hospital length of stay by zero-truncated negative binomial regression model analysis. CONCLUSION: The sepsis-related mortality and resource utilization are high in this population as well. Comorbidities and advanced age were some of the most important contributors to hospital mortality and resource utilization.

Anesthetic management for a five-day separation of craniopagus twins.

UNLABELLED: Craniopagus twinning is a rare form of the already uncommon entity of conjoint twins. With advances in medical technology and expertise, future attempts at surgical separation of these increasingly complex cases are likely to occur. Despite this, medical literature on the anesthetic management of these cases is sparse. The following case report details the anesthetic management and planning leading to and including the 5-dy separation of 11-mo-old craniopagus twins. The report emphasizes the importance of teamwork, communication, and advanced planning required in cases such as this. IMPLICATIONS: The following case report documents the anesthetic planning and management leading to and including a 5-day separation of twins joined at the head. This case report also details the difficulties encountered during the unique combination of a rarely performed procedure and a long operating time.

A comparative study of three warming interventions to determine the most effective in maintaining perioperative normothermia.

UNLABELLED: Perioperative hypothermia poses a challenge because of its deleterious effects on patient recovery. The current practice of applying two cotton blankets on patients during surgery is thought to be less ideal than using reflective insulation or forced-air warming. We studied 300 patients who underwent unilateral total knee replacement and were randomized equally to three groups: (a) the two-cotton-blanket group, (b) the one-reflective-blanket with one-cotton-blanket group, and (c) the forced-air-warming with one-cotton-blanket group. Tympanic temperature readings were taken before surgery in the induction room, on arrival at the recovery room, and at 10-min intervals until discharge from the recovery room. On arrival at the recovery room, the forced-air-warming group had significantly higher temperatures (adjusted for sex, age, and patient's induction room temperature) of 0.577 degrees C +/- 0.079 degrees C (95% confidence interval [CI], 0.427-0.726; P < 0.001) and 0.510 degrees C +/- 0.08 degrees C (95% CI, 0.349-0.672; P < 0.001) more than the reflective-blanket and two-cot-ton-blanket groups, respectively. The forced-air-warming group took a significantly (P < 0.001) shorter time of 18.75 min (95% CI, 13.88-23.62) to achieve a temperature of 36.5 degrees C in the recovery room as compared with 41.78 min (95% CI, 36.86-46.58) and 36.43 min (95% CI, 31.23-41.62) for the reflective-blanket and two-cotton-blanket groups, respectively. The reflective technology was less effective than using two cotton blankets, and the forced-air warming was most efficient in maintaining perioperative normothermia. IMPLICATIONS: Perioperative hypothermia has deleterious effects on patient recovery. We found in patients having knee surgery that reflective technology was less effective than using two cotton blankets, whereas active surface warming with the forced-air method was most effective in maintaining normothermia.