The impact of elective surgery postponement during COVID-19 on emergency bellwether procedures in a large tertiary centre in Singapore.

The coronavirus disease 2019 (COVID-19) pandemic drove many healthcare systems worldwide to postpone elective surgery to increase healthcare capacity, manpower, and reduce infection risk to staff. The aim of this study was to assess the impact of an elective surgery postponement policy in response to the COVID-19 pandemic on surgical volumes and patient outcomes for three emergency bellwether procedures. A retrospective cohort study of patients who underwent any of the three emergency procedures [Caesarean section (CS), emergency laparotomy (EL), and open fracture (OF) fixation] between 1 January 2018 and 31 December 2021 was conducted using clinical and surgical data from electronic medical records. The volumes and outcomes of each surgery were compared across four time periods: pre-COVID (January 2018-January 2020), elective postponement (February-May 2020), recovery (June-November 2020), and postrecovery (December 2020-December 2021) using Kruskal-Wallis test and segmented negative binomial regression. There was a total of 3886, 1396, and 299 EL, CS, and OF, respectively. There was no change in weekly volumes of CS and OF fixations across the four time periods. However, the volume of EL increased by 47% [95% confidence interval: 26-71%, P = 9.13 × 10-7) and 52% (95% confidence interval: 25-85%, P = 3.80 × 10-5) in the recovery and postrecovery period, respectively. Outcomes did not worsen throughout the four time periods for all three procedures and some actually improved for EL from elective postponement onwards. Elective surgery postponement in the early COVID-19 pandemic did not affect volumes of emergency CS and OF fixations but led to an increase in volume for EL after the postponement without any worsening of outcomes.

Estimating the pertussis burden in adolescents and adults in the United States between 2007 and 2019.

We developed a machine learning algorithm to identify undiagnosed pertussis episodes in adolescent and adult patients with reported acute respiratory disease (ARD) using clinician notes in an electronic healthcare record (EHR) database. Here, we utilized the algorithm to better estimate the overall pertussis incidence within the Optum Humedica clinical repository from 1 January 2007 through 31 December 2019. The incidence of diagnosed pertussis episodes was 1-5 per 100,000 annually, consistent with data registered by the US Centers for Disease Control and Prevention (CDC) over the same time period. Among 18,573,496 ARD episodes assessed, 1,053,946 were identified (i.e. algorithm-identified) as likely undiagnosed pertussis episodes. Accounting for these undiagnosed pertussis episodes increased the estimated pertussis incidence by 110-fold on average (34-474 per 100,000 annually). Risk factors for pertussis episodes (diagnosed and algorithm-identified) included asthma (Odds ratio [OR] 2.14; 2.12-2.16), immunodeficiency (OR 1.85; 1.78-1.91), chronic obstructive pulmonary disease (OR 1.63; 1.61-1.65), obesity (OR 1.44; 1.43-1.45), Crohn's disease (OR 1.39; 1.33-1.45), diabetes type 1 (OR 1.21; 1.17-1.24) and type 2 (OR 1.12; 1.1-1.13). Of note, all these risk factors, except Crohn's disease, increased the likelihood of severe pertussis. In conclusion, the incidence of pertussis in the adolescent and adult population in the USA is likely substantial, but considerably under-recognized, highlighting the need for improved clinical awareness of the disease and for improved control strategies in this population. These results will help better inform public health vaccination and booster programs, particularly in those with underlying comorbidities.

Development of an algorithm for finding pertussis episodes in a population-based electronic health record database.

While tetanus-diphtheria-acellular pertussis (Tdap) vaccines for adolescents and adults were licensed in 2005 and immunization strategies proposed, the burden of pertussis in this population remains under-recognized mainly due to atypical disease presentation, undermining efforts to optimize protection through vaccination. We developed a machine learning algorithm to identify undiagnosed/misdiagnosed pertussis episodes in patients diagnosed with acute respiratory disease (ARD) using signs, diseases and symptoms from clinician notes and demographic information within electronic health-care records (Optum Humedica repository [2007-2019]). We used two patient cohorts aged ≥11 years to develop the model: a positive pertussis cohort (4,515 episodes in 4,316 patients) and a negative pertussis (ARD) cohort (4,573,445 episodes and patients), defined using ICD 9/10 codes. To improve contrast between positive pertussis and negative pertussis (ARD) episodes, only episodes with ≥7 symptoms were selected. LightGBM was used as the machine learning model for pertussis episode identification. Model validity was determined using laboratory-confirmed pertussis positive and negative cohorts. Model explainability was obtained using the Shapley additive explanations method. The predictive performance was as follows: area under the precision-recall curve, 0.24 (SD, 7 × 10-3); recall, 0.72 (SD, 4 × 10-3); precision, 0.012 (SD, 1 × 10-3); and specificity, 0.94 (SD, 7 × 10-3). The model applied to laboratory-confirmed positive and negative pertussis episodes had a specificity of 0.846. Predictive probability for pertussis increased with presence of whooping cough, whoop, and post-tussive vomiting in clinician notes, but decreased with gastrointestinal bleeding, sepsis, pulmonary symptoms, and fever. In conclusion, machine learning can help identify pertussis episodes among those diagnosed with ARD.

Association of COVID-19 'circuit breaker' with higher rates of elderly trauma admissions.

Introduction: In December 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) virus emerged and caused a worldwide pandemic, leading to measures being imposed by many countries to reduce its transmission. Singapore implemented the 'circuit breaker', which restricted all movements except for access to necessities and healthcare services. We aimed to investigate the impact of lockdown measures on the pattern of trauma and its effects. Methods: An observational, retrospective, single-centre descriptive study was conducted using the trauma registry in Singapore General Hospital. It included patients above 18 years old who presented to the emergency department with trauma and were subsequently admitted. Patients admitted from 1 February 2020 to 31 July 2020 and those admitted during the same timeframe in 2019 were studied. Subgroup analyses were performed for patients aged ≥65 years and those <65 years. Results: A total of 1,037 patients were included for analysis. A 17.6% increase in trauma presentations was seen from 2019 to 2020. Patients aged ≥65 years accounted for the rise in admissions. The predominant mechanism of injury was falls at home for older patients and vehicular accidents in patients <65 years. There were no significant differences in injury severity score, intensive care/high-dependency unit admission rates, length of stay, mortality rate, and subsequent need for inpatient rehabilitation. Conclusion: Our study provided information on differences in trauma presentations before and during the COVID-19 pandemic. Further studies are required to better inform on additional precautionary measures needed to reduce trauma and improve safety during future lockdowns and pandemics.

Pearls & Oy-sters: Sequential Bilateral Hearing and Vision Loss With Optic Disc Swelling Due to Sphenoid Bone Craniofacial Fibrous Dysplasia.

Bilateral optic disc swelling is a common finding but rarely associated with multiple cranial neuropathies. In this case, an 18-year-old man presented with subacute sequential hearing loss followed by subacute sequential visual loss. Clinical examination revealed bilateral optic disc swelling. Lumbar puncture revealed a normal opening pressure of 15 cmH2o. This case discusses a rare but important cause of bilateral optic disc swelling in the context of hearing loss, disequilibrium, and a normal CSF opening pressure. An overview of the literature is provided, and treatment options are discussed to guide further management of similar cases.

Cavernous sinus haemangioma: systematic review and pooled analysis relating to a rare skull base pathology.

Cavernous sinus haemangiomas (CSHs) are rare malformations of the microcirculation arising from the cavernous sinus. A systematic review and pooled data analysis of the associated clinical features, diagnostic modalities, management, and outcomes for CSHs was done. In total, 68 articles (338 cases) were eligible for analysis based on our selection criteria. The primary outcome measures were the occurrence of (i) and (ii) symptom resolution/improvement. Categorical outcome variables were assessed by binary logistic regression at 5% significance level. With headaches (39.9%) and diplopia (36.5%) as the most common presenting symptoms reported, dynamic contrast-enhanced MRI was the most commonly used diagnostic modality and was the most definitive pre-treatment imaging modality for diagnosing CSH with a sensitivity of 89.5%. The majority of CSHs were managed with radiosurgery (47.9% of cases), 37.9% by surgical resection alone, and 14.2% by a combination of both. Compared to patients that were treated with surgical resection only, those treated solely with radiosurgery had a 100% decrease in the odds of developing post-treatment complications (adjusted OR: 0.00, 95% CI: 0.00-0.002, p < 0.001), with a 5.03 times greater odds of symptom resolution/improvement (adjusted OR: 5.03, 95% CI: 1.89-13.4, p = 0.001). Patients that underwent combined therapy had a 79% reduction in risk of developing post-treatment complications (adjusted OR: 0.21, 95% CI: 0.06-0.68, p = 0.01), with no statistically significant difference in the odds of symptom resolution/improvement, compared to those that had surgery only. In conclusion, radiosurgery offered the best outcomes with regards to symptom resolution/improvement and post-treatment complications in patients with CSH.

A clinical predictive model for risk stratification of patients with severe acute lower gastrointestinal bleeding.

BACKGROUND: Lower gastrointestinal bleeding (LGIB) is a common presentation of surgical admissions, imposing a significant burden on healthcare costs and resources. There is a paucity of standardised clinical predictive tools available for the initial assessment and risk stratification of patients with LGIB. We propose a simple clinical scoring model to prognosticate patients at risk of severe LGIB and an algorithm to guide management of such patients. METHODS: A retrospective cohort study was conducted, identifying consecutive patients admitted to our institution for LGIB over a 1-year period. Baseline demographics, clinical parameters at initial presentation and treatment interventions were recorded. Multivariate logistic regression was performed to identify factors predictive of severe LGIB. A clinical management algorithm was developed to discriminate between patients requiring admission, and to guide endoscopic, angiographic and/or surgical intervention. RESULTS: 226/649 (34.8%) patients had severe LGIB. Six variables were entered into a clinical predictive model for risk stratification of LGIB: Tachycardia (HR ≥ 100), hypotension (SBP < 90 mmHg), anaemia (Hb < 9 g/dL), metabolic acidosis, use of antiplatelet/anticoagulants, and active per-rectal bleeding. The optimum cut-off score of ≥ 1 had a sensitivity of 91.9%, specificity of 39.8%, and positive and negative predictive Values of 45% and 90.2%, respectively, for predicting severe LGIB. The area under curve (AUC) was 0.77. CONCLUSION: Early diagnosis and management of severe LGIB remains a challenge for the acute care surgeon. The predictive model described comprises objective clinical parameters routinely obtained at initial triage to guide risk stratification, disposition and inpatient management of patients.

Systematic review of the efficacy of a hybrid operating theatre in the management of severe trauma.

BACKGROUND: Hybrid operating theatres (OT) allow for simultaneous interventional radiology and operative procedures, serving as a one-stop facility for the treatment of severely injured patients. Several countries have adopted the use of the hybrid OT however their clinical impact in improving efficiency and quality of care remains unclear. This study systematically reviews the clinical impact of the hybrid OT for treatment of the severely injured. METHODS: A literature review of the PubMed, Embase and Cochrane databases was performed to identify all published articles in English, from 1st January 2000 to 31st December 2020, reporting on the impact of a hybrid OT for severe trauma. Articles were also reviewed for references of interest. RESULTS: Five studies reporting the clinical impact of the hybrid OT, in a total of 951 patients, were shortlisted. All were cohort studies that compared patient outcomes in the hybrid OT versus a conventional group. Out of 3 studies that assessed timeliness to intervention, one reported shorter time associated with the hybrid OT, while the other two reported no difference. Mortality outcomes were reported in 4 studies and showed no significant difference associated with treatment in the hybrid OT. Two studies revealed shorter total procedure times associated with the hybrid OT. Two out of 3 studies that evaluated blood transfusion requirements reported decreased transfusion rates in the hybrid OT group. Only 1 study examined complication rates and demonstrated morbidity benefits associated with the hybrid OT. CONCLUSION: Establishment of a hybrid OT requires a significant capital investment as well as a highly functioning multi-disciplinary team. The cost-benefit ratio remains unclear. Future studies, preferably in the form of clinical trials, are required to evaluate its usefulness in improving timeliness to definitive haemorrhage control and outcomes in severe trauma.

Linguistic markers predict onset of Alzheimer's disease.

BACKGROUND: The aim of this study is to use classification methods to predict future onset of Alzheimer's disease in cognitively normal subjects through automated linguistic analysis. METHODS: To study linguistic performance as an early biomarker of AD, we performed predictive modeling of future diagnosis of AD from a cognitively normal baseline of Framingham Heart Study participants. The linguistic variables were derived from written responses to the cookie-theft picture-description task. We compared the predictive performance of linguistic variables with clinical and neuropsychological variables. The study included 703 samples from 270 participants out of which a dataset consisting of a single sample from 80 participants was held out for testing. Half of the participants in the test set developed AD symptoms before 85 years old, while the other half did not. All samples in the test set were collected during the cognitively normal period (before MCI). The mean time to diagnosis of mild AD was 7.59 years. FINDINGS: Significant predictive power was obtained, with AUC of 0.74 and accuracy of 0.70 when using linguistic variables. The linguistic variables most relevant for predicting onset of AD have been identified in the literature as associated with cognitive decline in dementia. INTERPRETATION: The results suggest that language performance in naturalistic probes expose subtle early signs of progression to AD in advance of clinical diagnosis of impairment. FUNDING: Pfizer, Inc. provided funding to obtain data from the Framingham Heart Study Consortium, and to support the involvement of IBM Research in the initial phase of the study. The data used in this study was supported by Framingham Heart Study's National Heart, Lung, and Blood Institute contract (N01-HC-25195), and by grants from the National Institute on Aging grants (R01-AG016495, R01-AG008122) and the National Institute of Neurological Disorders and Stroke (R01-NS017950).

Development of an enhanced acute care surgery service in response to the COVID-19 global pandemic.

BACKGROUND: As the COVID-19 pandemic sweeps across the world, healthcare departments must adapt to meet the challenges of service provision and staff/patient protection. Unlike elective surgery, acute care surgery (ACS) workloads cannot be artificially reduced providing a unique challenge for administrators to balance healthcare resources between the COVID-19 surge and regular patient admissions. METHODS: An enhanced ACS (eACS) model of care is described with the aim of limiting COVID-19 healthcare worker and patient cross-infection as well as providing 24/7 management of emergency general surgical (GS) and trauma patients. The eACS service comprised 5 independent teams covering a rolling 1:5 24-hr call. Attempts to completely separate eACS teams and patients from the elective side were made. The service was compared to the existing ACS service in terms of clinical and efficiency outcomes. Finally, a survey of staff attitudes towards these changes, concerns regarding COVID-19 and psychological well-being was assessed. RESULTS: There were no staff/patient COVID-19 cross-infections. Compared to the ACS service, eACS patients had reduced overall length of stay (2-days), time spent in the Emergency Room (46 min) and time from surgery to discharge (2.4-hours). The eACS model of care saved financial resources and bed-days for the organisation. The changes were well received by team-members who also felt that their safety was prioritised. CONCLUSION: In healthcare systems not overwhelmed by COVID-19, an eACS model may assist in preserving psychological well-being for healthcare staff whilst providing 24/7 care for emergency GS and trauma patients.

Evolution of a Dedicated Emergency Surgery and Trauma (ESAT) unit over 3 years: sustained improved outcomes.

INTRODUCTION: The traditional 24-h call model faces pressure from competing needs between emergency and elective services. Recognizing this, a dedicated ESAT service was developed in Khoo Teck Puat Hospital in Singapore, with improved clinical outcomes. It was initially led by a single consultant (SC) in 2014, and subsequently evolved to a weekly consultant rotation (WC) roster in 2017 to achieve sustainability. METHODS: Each consultant led the ESAT WC service for a week and maintained ownership of their patients thereafter. All emergency surgical admissions between two distinct 6-month periods were reviewed, from May to October 2014 (pre-ESAT) and January to June 2017 (ESAT WC). Patient demographics, diagnoses, and operations were compared. Efficiency and clinical outcomes were evaluated. RESULTS: There were 1248 and 1284 patients in the pre-ESAT and ESAT WC group, respectively. Majority were males and in their 50s. Acute appendicitis, gallstone conditions, and soft-tissue infections made up half of the admissions. Trauma workload was comparable (7.8% pre-ESAT vs 9.5% ESAT WC). Cholecystectomies doubled during the ESAT period, 14.2% vs 7.2%, (p = 0.01). More consultants were involved in major cases (95.9% vs 86%), (p = 0.01) and more operations were performed during the day (52.1% vs 47.9%), (p = 0.01). Average time to OT was shorter and there were less major surgical complications (p = 0.02). Mortality (p = 0.08) and length of stay were reduced (4 vs 4.5 days), (p = 0.01). CONCLUSION: The ESAT WC service has sustained improved outcomes in our institution.

The clinical approach to managing herpes simplex virus encephalitis.

This article explains the approach to managing a patient with herpes simplex virus encephalitis. Acute encephalopathy is a common and often intimidating presentation in an acute general medical setting. Application of key principles will enable the generalist to take life-saving action before obtaining any specialist input. Viral infection is the most common cause (48.2%) of encephalitis; another large group is cases of autoimmune aetiology. Early diagnosis of encephalitis is crucial to ensure that the right treatment is given on time. Guidelines on the management of viral encephalitis were published by the British Association of Neurologists and British Infection Association ( Solomon et al, 2012 ), but adherence to these standards by clinicians has been found to be suboptimal ( Han and Coebergh, 2017 ). This puts lives in danger, in the context of a treatable, serious, acute presentation. Although viral infection is the most common cause of encephalitis, an awareness of rarer forms of autoimmune encephalitis is necessary. The differential diagnosis of autoimmune encephalitis is important because the disease is potentially treatable with immunosuppressive agents. Paraneoplastic limbic encephalitis may present months or years before the detection of a tumour.

Outcomes of emergency thoracotomy for trauma in a general hospital in Singapore.

Background An emergency thoracotomy can be performed either immediately at the site of trauma or in the emergency department or operating room for resuscitation of patients in extremis or life-saving treatment for patients with thoracic injury. It remains a procedure associated with high mortality rates, and there is a paucity of data from Asia. This study analyzed our six-year experience of emergency trauma thoracotomy in an acute general hospital in Singapore. Methods This retrospective analysis was based on experience in a single institution with all emergency trauma thoracotomies performed by general surgeons. All patients who underwent an emergency trauma thoracotomy in Khoo Teck Puat Hospital between January 2011 and December 2016 were studied. Data collected included patient demographics, mechanism of injury, Injury Severity Scores, surgical approach, and postoperative outcomes. Results Twenty-three patients underwent an emergency thoracotomy, 8 in the emergency department and 15 in the operating room. The mechanism of injury was blunt in 20 (87%) patients and penetrating in 3 (13%), with road traffic accidents the most common cause (70%). Six (40%) patients who underwent an emergency thoracotomy in the operating room survived beyond 24 h, and 4 (27%) survivors were eventually discharged from the hospital with no neurological deficit. No patient who underwent a thoracotomy in the emergency department survived beyond 24 h. Conclusions Emergency thoracotomy is associated with high mortality rates, especially when required in the emergency department or for blunt trauma. Nevertheless, it is a potentially life-saving procedure that offers a chance of survival in selected patients.

Emergency general surgery and trauma: Outcomes from the first consultant-led service in Singapore.

INTRODUCTION: There is a significant burden on public health systems from emergency surgical and trauma (ESAT) patients. In Western countries, the response has been to separate acute and elective surgery with the creation of a new sub-specialty: acute care surgery. Dedicated acute units have shown improvements in efficiency and clinical outcomes for patients. The aim of this study was to assess the results of the first such unit in Singapore. MATERIALS AND METHODS: A retrospective analysis was performed of a 12-month period of acute admissions between May 2014 and April 2015, with comparison of 6-months before and after the creation of the ESAT service. The ESAT service was a consultant led dedicated team managing all daily acute and trauma patients. Demographic, efficiency and clinical outcome key performance indicators were compared. RESULTS: There were 2527 acute admissions split between the two time periods. The ESAT service (N=1279) managed soft tissue infections (257, 20%), appendicitis (199, 16%) and biliary disease (175, 14%) most commonly. The most common of the 573 procedures performed were incision and drainage (242, 42%), appendicectomy (188, 33%) and laparotomy (84, 16%). Clinical outcome during the ESAT service included reduction in overall mean length of stay (4.5d to 3.5d, P<0.01) and mortality (24/1248 (1.9%) to 11/1279 (0.9%), P=0.03). Efficiency gains in theatre booking time, ED surgical review and overall costs were also noted. CONCLUSION: The creation of an ESAT service has led to improved efficiency of care with no worsening of clinical outcomes for acute general surgical and trauma patients.

In vitro and in vivo effects of 2,4 diaminoquinazoline inhibitors of the decapping scavenger enzyme DcpS: Context-specific modulation of SMN transcript levels.

C5-substituted 2,4-diaminoquinazoline inhibitors of the decapping scavenger enzyme DcpS (DAQ-DcpSi) have been developed for the treatment of spinal muscular atrophy (SMA), which is caused by genetic deficiency in the Survival Motor Neuron (SMN) protein. These compounds are claimed to act as SMN2 transcriptional activators but data underlying that claim are equivocal. In addition it is unclear whether the claimed effects on SMN2 are a direct consequence of DcpS inhibitor or might be a consequence of lysosomotropism, which is known to be neuroprotective. DAQ-DcpSi effects were characterized in cells in vitro utilizing DcpS knockdown and 7-methyl analogues as probes for DcpS vs non-DcpS-mediated effects. We also performed analysis of Smn transcript levels, RNA-Seq analysis of the transcriptome and SMN protein in order to identify affected pathways underlying the therapeutic effect, and studied lysosomotropic and non-lysosomotropic DAQ-DCpSi effects in 2B/- SMA mice. Treatment of cells caused modest and transient SMN2 mRNA increases with either no change or a decrease in SMNΔ7 and no change in SMN1 transcripts or SMN protein. RNA-Seq analysis of DAQ-DcpSi-treated N2a cells revealed significant changes in expression (both up and down) of approximately 2,000 genes across a broad range of pathways. Treatment of 2B/- SMA mice with both lysomotropic and non-lysosomotropic DAQ-DcpSi compounds had similar effects on disease phenotype indicating that the therapeutic mechanism of action is not a consequence of lysosomotropism. In striking contrast to the findings in vitro, Smn transcripts were robustly changed in tissues but there was no increase in SMN protein levels in spinal cord. We conclude that DAQ-DcpSi have reproducible benefit in SMA mice and a broad spectrum of biological effects in vitro and in vivo, but these are complex, context specific, and not the result of simple SMN2 transcriptional activation.