Novel approach to the derivation of dam breach parameters in 2D hydrodynamic modeling of earthquake induced dam failures

Current methods of dam breach analyses adopt a deterministic approach. Applying these methods to Concrete Faced Rockfill Dams (CFRD) is fraught with huge levels of uncertainty, especially in the context of natural hazards. The frequency and magnitude of rainfall and earthquakes are higher in today's world. In the literature, the complete collapse of dams is modelled on dam breach parameters that define the dam break outflow but are not related to the return periods of natural hazards. As more new dams are constructed to control the floods in intra-plate seismic regions, this study presents a novel approach to the derivation of generalized dam break parameters for CFRD based on the structural analysis of Finite Element Model (FEM) simulations for peak ground accelerations corresponding to 475 and 2475 year return periods. Furthermore, the occurrence of rainfall and earthquake for different return periods are modelled using 2D hydrodynamic simulations. Results show the significance of generalized dam breach parameters for planning and managing CFRDs during earthquakes. The study emphasizes the utilization of structural analysis outputs for the hydraulic modeling of dam breaks, which will result in more specific and accurate dam break parameters. Additionally, the study has shown that the flood risk and the severity will increase with the intensity of earthquake and rainfall magnitudes. Disaster mitigation strategies can be optimized by considering the integrated occurrence of rainfall and earthquakes based on the probability of occurrence, demonstrated using a case-study dam. Another significant outcome of the study is the effect of soil saturation condition during a dam break, which reveals that areas within 40 km of the dam breach location might be worst affected.

AZD1222 effectiveness against severe COVID-19 in individuals with comorbidity or frailty: The RAVEN cohort study

OBJECTIVES

Despite being prioritized during initial COVID-19 vaccine rollout, vulnerable individuals at high risk of severe COVID-19 (hospitalization, intensive care unit admission, or death) remain underrepresented in vaccine effectiveness (VE) studies. The RAVEN cohort study (NCT05047822) assessed AZD1222 (ChAdOx1 nCov-19) two-dose primary series VE in vulnerable populations.

METHODS

Using the Oxford-Royal College of General Practitioners Clinical Informatics Digital Hub, linked to secondary care, death registration, and COVID-19 datasets in England, COVID-19 outcomes in 2021 were compared in vaccinated and unvaccinated individuals matched on age, sex, region, and multimorbidity.

RESULTS

Over 4.5 million AZD1222 recipients were matched (mean follow-up ∼5 months); 68% were ≥50 years, 57% had high multimorbidity. Overall, high VE against severe COVID-19 was demonstrated, with lower VE observed in vulnerable populations. VE against hospitalization was higher in the lowest multimorbidity quartile (91.1%; 95% CI: 90.1, 92.0) than the highest quartile (80.4%; 79.7, 81.1), and among individuals ≥65 years, higher in the 'fit' (86.2%; 84.5, 87.6) than the frailest (71.8%; 69.3, 74.2). VE against hospitalization was lowest in immunosuppressed individuals (64.6%; 60.7, 68.1).

CONCLUSIONS

Based on integrated and comprehensive UK health data, overall population-level VE with AZD1222 was high. VEs were notably lower in vulnerable groups, particularly the immunosuppressed.

Hyperkalaemia-related reduction of RAASi treatment associates with more subsequent inpatient care

BACKGROUND

Hyperkalaemia is a barrier to achieving optimal, guideline-directed treatment with renin-angiotensin-aldosterone system inhibitors (RAASi) in patients with chronic kidney disease (CKD) and/or heart failure (HF). This study describes the association between hyperkalaemia-related RAASi treatment reduction and number of hospitalized days in patients with CKD and/or HF in Sweden and Japan.

METHODS

Using data from health registers and hospital medical records, patients with CKD and/or HF currently receiving RAASi who experienced an index hyperkalaemia episode were identified and categorized as having maintained or reduced RAASi treatment post-index; propensity-score matching (1:1) was applied to balance the groups in terms of baseline characteristics. Changes in the number of all-cause, CKD-, and HF-related hospitalized days per patient-year during 6 months before versus after index, and the number of days alive and out of hospital (DAOH) during 6 months post-index were described.

RESULTS

Overall, 20 824 and 7789 patients were included from Sweden and Japan, respectively, 42% and 38% of whom reduced their RAASi treatment after the index hyperkalaemia episode. During the 6 months post-index, all-cause hospitalization (95% confidence intervals) increased by 18.2 (17.0-19.2) days per person-year in Sweden and 17.9 (17.4-18.5) days per person-year in Japan among patients with reduced RAASi treatment compared with increases of 9.4 (8.6-10.4) and 8.5 (8.0-9.0) days per person-year, respectively, among patients with maintained RAASi treatment. Mean (standard deviation) DAOH were 121.5 (75.0) in Sweden and 141.7 (54.5) in Japan among patients with reduced RAASi treatment compared with 154.0 (51.3) and 157.5 (31.6) days, respectively, among patients with maintained RAASi treatment.

CONCLUSION

Patients whose RAASi treatment was reduced after a hyperkalaemia episode had more hospitalized days and fewer DAOH compared with patients whose RAASi treatment was maintained.

Impact of COVID-19 on immunocompromised populations during the Omicron era: insights from the observational population-based INFORM study

Background

Immunocompromised individuals are not optimally protected by COVID-19 vaccines and potentially require additional preventive interventions to mitigate the risk of severe COVID-19. We aimed to characterise and describe the risk of severe COVID-19 across immunocompromised groups as the pandemic began to transition to an endemic phase.

Methods

COVID-19-related hospitalisations, intensive care unit (ICU) admissions, and deaths (01/01/2022-31/12/2022) were compared among different groups of immunocompromised individuals vs the general population, using a retrospective cohort design and electronic health data from a random 25% sample of the English population aged ≥12 years (Registration number: ISRCTN53375662).

Findings

Overall, immunocompromised individuals accounted for 3.9% of the study population, but 22% (4585/20,910) of COVID-19 hospitalisations, 28% (125/440) of COVID-19 ICU admissions, and 24% (1145/4810) of COVID-19 deaths in 2022. Restricting to those vaccinated with ≥3 doses of COVID-19 vaccine (∼84% of immunocompromised and 51% of the general population), all immunocompromised groups remained at increased risk of severe COVID-19 outcomes, with adjusted incidence rate ratios (aIRR) for hospitalisation ranging from 1.3 to 13.1. At highest risk for COVID-19 hospitalisation were individuals with: solid organ transplant (aIRR 13.1, 95% confidence interval [95% CI] 11.2-15.3), moderate to severe primary immunodeficiency (aIRR 9.7, 95% CI 6.3-14.9), stem cell transplant (aIRR 11.0, 95% CI 6.8-17.6), and recent treatment for haematological malignancy (aIRR 10.6, 95% CI 9.5-11.9). Results were similar for COVID-19 ICU admissions and deaths.

Interpretation

Immunocompromised individuals continue to be impacted disproportionately by COVID-19 and have an urgent need for additional preventive measures beyond current vaccination programmes. These data can help determine the immunocompromised groups for which targeted prevention strategies may have the highest impact.

Funding

This study was funded by AstraZeneca UK.

Acute pulmonary embolism: in hospital outcome from a prospective observational registry (M-PER) from a low-and middle-income country

Background

Acute Pulmonary embolism the third most common cause of cardiovascular death in the world. Despite the large burden of acute pulmonary embolism, there is a paucity of prospective data from low-and middle-income countries.

Purpose

To study the clinical characteristics, treatment strategies employed, in-hospital outcome, one-year follow up results, and the prognostic factors in patients with acute pulmonary embolism from a low-and middle-income country.

Methods

All consecutive patients diagnosed with and treated for acute pulmonary embolism at our institution from November 2016 to November 2021 were included in the registry. Pulmonary embolism was diagnosed using clinical features (Wells' criteria of ≥3) supported by either CT angiogram or echocardiogram. Detailed history, clinical examination, preliminary basic blood investigations, cardiac troponins along with coagulation workup, ECG and ECHO were done for all patients. Patients were classified as having massive or high risk, submassive or intermediate risk and low risk pulmonary embolism based hemodynamic status, sPESI score, echocardiogram and cardiac troponins. Treatment was at the discretion of treating physician. In general, all patients with massive pulmonary embolism were considered for thrombolysis. All patients received anticoagulation with unfractionated heparin. Outcomes included hospital lengths of stay, all-cause in-hospital mortality and one year mortality

Results

186 patients with acute pulmonary embolism were prospectively enrolled during period. 62% were male. Mean age was 42.38±13.4 years. The risk factors noticed include prior history of venous thromboembolism, active malignancy, recent surgery, trauma, immobilisation, diabetes, hypertension, and chronic obstructive pulmonary disease in 18%, 5%, 10%, 8%, 14%, 17%, 10% and 3% of our patients respectively. Shortness of breath (98%), chest pain (37%), leg swelling (37%), cough (33%), shock (27%), syncope (15%) and haemoptysis (12%) were the reasons for presentation. Sinus tachycardia was the commonest finding (80%).

Right ventricular (RV) strain pattern was present in 68%, S1Q3T3 pattern in 56% and RBBB in 32%. RV dilatation was present in 93% and RV dysfunction in 75%. Thrombus was visualised in the pulmonary artery in 37% and right heart chambers in 12% (714). 26% were classified as high risk, 60% as intermediate risk and 13.4% as low risk acute pulmonary embolism. Overall 50% (92% of high-risk and 41% of intermediate risk) patients received fibrinolytic therapy.

In hospital mortality was 16% (29 patients) of which 72% were from high-risk group. In the high-risk group those who were fibrinolysed had a lower mortality compared to those not lysed. (75% vs 40%). This difference was not observed in the intermediate risk group.

Conclusion

Acute pulmonary embolism is a disease with high in-hospital mortality. Fibrinolytic therapy with streptokinase has a lifesaving potential in high risk patients.

Funding Acknowledgement

Type of funding sources: None.

Two factor authentication protocol for IoT based healthcare monitoring system

In the last few years, technological advancement has led to the use of wearable body sensors for gathering patient information. Wireless body area networks played an essential role in the modern medical era. Through wearable body sensors, patient data are sent to medical professionals in real-time without any hindrance. This information moves through the public channel, and thus proper security and protection are needed because of its sensitiveness. Many authentication protocols proposed for solving these issues were neither secure nor cost-effective. This paper proposed an authentication protocol using certificateless cryptography for wireless body area networks to resolve the associated security concerns. A formal security analysis is done using the Burrows-Abadi-Needham logic shows that the proposed protocol is resilient against prevailing attacks. Additionally, we employ the Real-or-Random model for mathematical proof and Automated Verification Security Protocol and Analysis simulation tool for security analysis. A detailed comprehensive comparison with the existing protocols indicates that the proposed protocol is cost-effective with improved functionality.

A Clinico Epidemiological Study of Adverse Cutaneous Manifestations on Using Personal Protective Equipment Among Health Care Workers During Covid Pandemic in a Tertiary Care Centre

Background

COVID-19 (Coronavirus Disease 2019) pandemic was caused by a novel coronavirus. The frontline health care workers (HCW), wearing personal protective equipment (PPE) for a longer duration can result in a spectrum of adverse skin reactions. Recognizing occupationally induced adverse skin manifestations from PPE is necessary to avoid skin damage and risk of infections and to maintain compliance.

Aim

This study aimed to determine the prevalence, clinical characteristics of adverse cutaneous manifestations due to PPE, and also the contributing epidemiological factors among HCW in a tertiary care institute.

Materials and Methods

This cross-sectional study was conducted for a period of one month. Four hundred fifteen health care workers who used PPE continuously for >4 hours voluntarily participated in this study. By using a self-administered online questionnaire, the information and clinical photographs were collected.

Results

The prevalence of adverse skin manifestations was 62.1% (258). The prevalence was more common in females. Mask-related facial skin problems were most commonly reported. Of 74 participants with pre-existing acne lesions, 35 (8.4%) reported acne flare-ups after using PPE. Increased sweating (22.6%) and itching (11%) were the most commonly noted symptoms.

Conclusion

This study provides an insight into the prevalence of adverse skin reactions due to prolonged PPE usages, such as N95 masks and latex gloves in particular. Hence dermatological screening of HCW at regular intervals is inevitable to facilitate early management and prevent inadvertent protocol breaches. Further, it proposes the importance of raising proper safety measures to effectively reduce the COVID positivity rate among HCW by minimizing and preventing occupationally induced dermatosis.

Vibration analysis of planetary gearbox using empirical mode decomposition and automatic fault prediction using artificial neural network

The planetary gearbox works on an epicyclic gear train consisting of sun gear meshed with planets gears and ring gear. It got advantages due to its large torque to weight ratio and reduced vibrations. It is mostly employed in analog clocks, automobile automatic gearbox, Lathe machines, and other heavy industries. Therefore, it was imperative to analyze the various faults occurring in a gearbox. Furthermore, come up with a method so that failures can be avoided at the early stage. It was also a reason why it became the field of intensive research. Moreover, the technology of neural networks emerged recently, where machine learning models are trained to detect uneven vibrations on their own. This attracted many researchers to perform the study to devise their own methods of prediction. The central concept of fault prediction by the neural network without human beings’ interference inspired this study. Most industries always wanted to know if their operation line is working fine or not. In this study, an attempt was made to apply the method of deep learning on one of the most critical gearboxes because of its components and functionality. A significant part of the study also involved filtering the vibration data obtained while testing. Comparative analysis of the variation of the peak of acceleration was performed for healthy and faulty conditions.

Isolated CNS relapse in FLT 3 mutation positive CMML post allogeneic stem cell transplant: Report of a rare case

Chronic myelomonocytic leukemia is a clonal chronic hematopoietic disorder that has been classified under the category of Myelodysplastic syndrome/Myeloproliferative neoplasms (MDS/MPN). CMML has high chances of transforming to acute leukemia, however isolated CNS relapse in CMML has never been reported in literature. We report an extremely rare case of a 47 yearold female diagnosed to have CMML- 2 in remission, who developed an isolated central nervous system relapse after matched related allogeneic hematopoietic stem cell transplantation. To our knowledge this is the first report of isolated CNS relapse in CMML post allogeneic stem cell transplant.

Patient characteristics associated with COVID-19 positivity and fatality in Nigeria: retrospective cohort study

OBJECTIVE

Despite the increasing disease burden, there is a dearth of context-specific evidence on the risk factors for COVID-19 positivity and subsequent death in Nigeria. Thus, the study objective was to identify context-specific factors associated with testing positive for COVID-19 and fatality in Nigeria.

DESIGN

Retrospective cohort study.

SETTING

COVID-19 surveillance and laboratory centres in 36 states and the Federal Capital Territory reporting data to the Nigeria Centre for Disease Control.

PARTICIPANTS

Individuals who were investigated for SARS-CoV-2 using real-time PCR testing during the study period 27 February-8 June 2020.

METHODS

COVID-19 positivity and subsequent mortality. Multivariable logistic regression analyses were performed to identify factors independently associated with both outcome variables, and findings are presented as adjusted ORs (aORs) and 95% CIs.

RESULTS

A total of 36 496 patients were tested for COVID-19, with 10 517 confirmed cases. Of 3215 confirmed cases with available clinical outcomes, 295 died. Factors independently associated with COVID-19 positivity were older age (p value for trend<0.0001), male sex (aOR 1.11, 95% CI 1.04 to 1.18) and the following presenting symptoms: cough (aOR 1.23, 95% CI 1.13 to 1.32), fever (aOR 1.45, 95% CI 1.45 to 1.71), loss of smell (aOR 7.78, 95% CI 5.19 to 11.66) and loss of taste (aOR 2.50, 95% CI 1.60 to 3.90). An increased risk of mortality following COVID-19 was observed in those aged ≥51 years, patients in farming occupation (aOR 7.56, 95% CI 1.70 to 33.53) and those presenting with cough (aOR 2.06, 95% CI 1.41 to 3.01), breathing difficulties (aOR 5.68, 95% CI 3.77 to 8.58) and vomiting (aOR 2.54, 95% CI 1.33 to 4.84).

CONCLUSION

The significant risk factors associated with COVID-19 positivity and subsequent mortality in the Nigerian population are similar to those reported in studies from other countries and should guide clinical decisions for COVID-19 testing and specialist care referrals.

Cross-covariance based affinity for graphs

The accuracy of graph based learning techniques relies on the underlying topological structure and affinity between data points, which are assumed to lie on a smooth Riemannian manifold. However, the assumption of local linearity in a neighborhood does not always hold true. Hence, the Euclidean distance based affinity that determines the graph edges may fail to represent the true connectivity strength between data points. Moreover, the affinity between data points is influenced by the distribution of the data around them and must be considered in the affinity measure. In this paper, we propose two techniques, C C G A _L and C C G A _N that use cross-covariance based graph affinity (CCGA) to represent the relation between data points in a local region. C C G A _L also explores the additional connectivity between data points which share a common local neighborhood. C C G A _N considers the influence of respective neighborhoods of the two immediately connected data points, which further enhance the affinity measure. Experimental results of manifold learning on synthetic datasets show that CCGA is able to represent the affinity measure between data points more accurately. This results in better low dimensional representation. Manifold regularization experiments on standard image dataset further indicate that the proposed CCGA based affinity is able to accurately identify and include the influence of the data points and its common neighborhood that increase the classification accuracy. The proposed method outperforms the existing state-of-the-art manifold regularization methods by a significant margin.

Neuraminidase Inhibitors and Hospital Length of Stay: A Meta-analysis of Individual Participant Data to Determine Treatment Effectiveness Among Patients Hospitalized With Nonfatal 2009 Pandemic Influenza A(H1N1) Virus Infection

Background

The effect of neuraminidase inhibitor (NAI) treatment on length of stay (LoS) in patients hospitalized with influenza is unclear.

Methods

We conducted a one-stage individual participant data (IPD) meta-analysis exploring the association between NAI treatment and LoS in patients hospitalized with 2009 influenza A(H1N1) virus (A[H1N1]pdm09) infection. Using mixed-effects negative binomial regression and adjusting for the propensity to receive NAI, antibiotic, and corticosteroid treatment, we calculated incidence rate ratios (IRRs) and 95% confidence intervals (CIs). Patients with a LoS of <1 day and those who died while hospitalized were excluded.

Results

We analyzed data on 18 309 patients from 70 clinical centers. After adjustment, NAI treatment initiated at hospitalization was associated with a 19% reduction in the LoS among patients with clinically suspected or laboratory-confirmed influenza A(H1N1)pdm09 infection (IRR, 0.81; 95% CI, .78–.85), compared with later or no initiation of NAI treatment. Similar statistically significant associations were seen in all clinical subgroups. NAI treatment (at any time), compared with no NAI treatment, and NAI treatment initiated <2 days after symptom onset, compared with later or no initiation of NAI treatment, showed mixed patterns of association with the LoS.

Conclusions

When patients hospitalized with influenza are treated with NAIs, treatment initiated on admission, regardless of time since symptom onset, is associated with a reduced LoS, compared with later or no initiation of treatment.

Antiviral treatment for outpatient use during an influenza pandemic: a decision tree model of outcomes averted and cost-effectiveness

Background

Many countries have acquired antiviral stockpiles for pandemic influenza mitigation and a significant part of the stockpile may be focussed towards community-based treatment.

Methods

We developed a spreadsheet-based, decision tree model to assess outcomes averted and cost-effectiveness of antiviral treatment for outpatient use from the perspective of the healthcare payer in the UK. We defined five pandemic scenarios—one based on the 2009 A(H1N1) pandemic and four hypothetical scenarios varying in measures of transmissibility and severity.

Results

Community-based antiviral treatment was estimated to avert 14–23% of hospitalizations in an overall population of 62.28 million. Higher proportions of averted outcomes were seen in patients with high-risk conditions, when compared to non-high-risk patients. We found that antiviral treatment was cost-saving across pandemic scenarios for high-risk population groups, and cost-saving for the overall population in higher severity influenza pandemics. Antiviral effectiveness had the greatest influence on both the number of hospitalizations averted and on cost-effectiveness.

Conclusions

This analysis shows that across pandemic scenarios, antiviral treatment can be cost-saving for population groups at high risk of influenza-related complications.

Association of maternal hemoglobin and iron stores with neonatal hemoglobin and iron stores

Background

One of the commonest causes of anemia in pregnancy is iron deficiency. This study aims at understanding and exploring the association between fetal and maternal iron status. Predelivery maternal hemoglobin (Hb) and iron stores, serum iron, ferritin, and soluble transferrin receptor (sTfR), were assessed and compared to the cord blood Hb and iron stores with an attempt to identify the level of maternal Hb and ferritin at which the fetal iron stores reduce, helping to identify the neonates who will require earlier iron supplementation.

Method

Four hundred eight participants were enrolled, and maternal and cord blood was collected at the time of delivery and tested for Hb and iron parameters. The results were statistically analyzed.

Results

Of all mothers, 27.2% mothers were anemic (Hb less than 11 g/dl). Of all newborns, 15.4% newborns had Hb less than 14 g/dl. There was a significant association between the maternal and cord blood iron, ferritin, sTfR and sTfR/log ferritin index. Eighty-five percent of the babies with cord blood Hb <14 g/dl had maternal serum ferritin (SF) <50 μg/L. Maternal SF <10 μg/l was associated with a significant number of babies with cord blood SF <75 μg/l (77.7%). One hundred sixty six neonates had sTfR 2 μg/ml or more. Of these, 80.7% had maternal SF <50 μg/l. Of the 115 newborns with a high sTfR/log ferritin index (>1.5), 56.5% had raised maternal sTfR (>2μg/ml).

Conclusion

In view of a significant association between maternal and neonatal Hb and iron stores, newborns of mothers with iron deficiency anemia (IDA) during pregnancy should be monitored and followed up after birth for development of IDA and early iron supplementation.

A novel framework for evaluating the impact of individual decision-making on public health outcomes and its potential application to study antiviral treatment collection during an influenza pandemic

The importance of accounting for social and behavioural processes when studying public health emergencies has been well-recognised. For infectious disease outbreaks in particular, several methods of incorporating individual behaviour have been put forward, but very few are based on established psychological frameworks. In this paper, we develop a decision framework based on the COM-B model of behaviour change to investigate the impact of individual decision-making on public health outcomes. We demonstrate the application of our decision framework in a proof-of-concept case study based on the 2009 A(H1N1) influenza pandemic in the UK. The National Pandemic Flu Service (NPFS) was set up in England during the pandemic as a means to provide antiviral (AV) treatment to clinically ill patients with influenza-like illness, via telephone calls or internet screening, thereby averting the need to see a doctor. The evaluated patients based on a clinical algorithm and authorised AV drugs for collection via community collection points. We applied our behavioural framework to evaluate the influence of human behaviour on AV collection rates, and subsequently to identify interventions that could help improve AV collection rates. Our model was validated against empirically collected pandemic data from 2009 in the UK. We also performed a sensitivity analysis to identify potentially effective interventions by varying model parameters. Using our behavioural framework in a proof-of-concept case study, we found that interventions geared towards increasing people's 'Capability' and 'Opportunity' are likely to result in increased AV collection, potentially resulting in fewer influenza-related hospitalisations and deaths. We note that important behavioural data from public health emergencies are largely scarce. Insights obtained from models such as ours can, not only be very useful in designing healthcare interventions, but also inform future data collection.

Plasma cell neoplasm with varied morphology: A report of two cases

Plasma cell (PC) neoplasm (PCN) with varied morphology has been described in the literature. The majority of clonal proliferation of PCs is composed of easily recognizable morphology in the bone marrow (BM). However, few cases may cause diagnostic complexity, as they exhibit varied cytological and architectural heterogeneity which may pose problem in morphological diagnosis and require the use of ancillary techniques like immunohistochemistry (IHC). We illustrate here two such cases of PCN with varied morphology in BM aspirate, in the form of clustering/rosetting and multiple clear cytoplasmic vacuoles, respectively, leading to varied differential diagnosis. However, later, the histopathological features on BM biopsy findings were relatively characteristic and IHC confirmed the final diagnosis. The morphological variants documented in both these cases are exceptional and representative of the various forms of atypical PCs.

Preoperative chronic beta-blocker prescription in elderly patients as a risk factor for postoperative mortality stratified by preoperative blood pressure: a cohort study

BACKGROUND

Recent data suggest that beta blockers are associated with increased perioperative risk in hypertensive patients. We investigated whether beta blockers were associated with an increased risk in elderly patients with raised preoperative arterial blood pressure.

METHODS

We conducted a propensity-score-matched cohort study of primary care data from the UK Clinical Practice Research Datalink (2004-13), including 84 633 patients aged 65 yr or over. Conditional logistic regression models, including factors that were significantly associated with the outcome, were constructed for 30-day mortality after elective noncardiac surgery. The effects of beta blockers (primary outcome), renin-angiotensin system (RAS) inhibitors, calcium-channel blockers, thiazides, loop diuretics, and statins were investigated at systolic and diastolic arterial pressure thresholds.

RESULTS

Beta blockers were associated with increased odds of postoperative 30-day mortality in patients with systolic hypertension (defined as systolic BP >140 mm Hg; adjusted odds ratio [aOR]: 1.92; 95% confidence interval [CI]: 1.05-3.51). After excluding patients for whom prior data suggest benefit from perioperative beta blockade (patients with prior myocardial infarction or heart failure), rather than adjusting for them, the point estimate shifted slightly (aOR: 2.06; 95% CI: 1.09-3.89). Compared with no use, statins (aOR: 0.35; 95% CI: 0.17-0.75) and thiazides (aOR: 0.28; 95% CI: 0.10-0.78) were associated with lower mortality in patients with systolic hypertension.

CONCLUSIONS

These data suggest that the safety of perioperative beta blockers may be influenced by preoperative blood pressure thresholds. A randomised controlled trial of beta-blocker withdrawal, in select populations, is required to identify a causal relationship.

Workplace-based assessment of family medicine competencies using "field note tool" - A pilot study

Background

Department of Family Medicine in a medical college in South India introduced "field note" (FN) as a tool for Work-Place Based Assessment in postgraduate training. FN collects "open-ended" feedback from both resident and faculty and helps them to arrive at an action plan. This study describes our experience of implementing FN and perceptions of learners and faculty.

Methods

While precepting the residents in Family Medicine service areas, faculty documented their observations of the resident's clinical work using FN and provided an action plan. Faculty and residents described their experience and provided feedback. Focus group discussions were conducted for faculty and residents. Data were coded and grouped into themes.

Results

Four residents and seven faculties participated in the study during 12 weeks period using 17 consultations. Clinical expert (13/17) and communicator (6/17) are the most commonly assessed competencies followed by professionalism (2/17) and collaborator (2/17). Faculty and residents agreed that "FN" was a useful tool and it helped the faculty to give feedback and guide the learner. Residents and faculty arrived at an action plan in 70% of the consultations. Three of four residents perceived the change in their behaviour positively after the use of FN. Both resident and faculty found the rating of the learner using Dreyfus scale as a barrier.

Conclusion

FN could be one of the important tools in our "Toolbox of Assessment Methods" for family medicine specialty. There is a need for sensitizing the learners to feedback process and training the faculty in assessment and feedback.

Cohort study of preoperative blood pressure and risk of 30-day mortality after elective non-cardiac surgery

Background

Preoperative blood pressure (BP) thresholds associated with increased postoperative mortality remain unclear. We investigated the relationship between preoperative BP and 30-day mortality after elective non-cardiac surgery.

Methods

We performed a cohort study of primary care data from the UK Clinical Practice Research Datalink (2004-13). Parsimonious and fully adjusted multivariable logistic regression models, including restricted cubic splines for numerical systolic and diastolic BP, for 30-day mortality were constructed. The full model included 29 perioperative risk factors, including age, sex, comorbidities, medications, and surgical risk scale. Sensitivity analyses were conducted for age (>65 vs <65 years old) and the timing of BP measurement.

Results

A total of 251 567 adults were included, with 589 (0.23%) deaths within 30 days of surgery. After adjustment for all risk factors, preoperative low BP was consistently associated with statistically significant increases in the odds ratio (OR) of postoperative mortality. Statistically significant risk thresholds started at a preoperative systolic pressure of 119 mm Hg (adjusted OR 1.02 [95% confidence interval (CI) 1.01-1.02]) compared with the reference (120 mm Hg) and diastolic pressure of 63 mm Hg [OR 1.24 (95% CI 1.03-1.49)] compared with the reference (80 mm Hg). As BP decreased, the OR of mortality risk increased. Subgroup analysis demonstrated that the risk associated with low BP was confined to the elderly. Adjusted analyses identified that diastolic hypertension was associated with increased postoperative mortality in the whole cohort.

Conclusions

In this large observational study we identified a significant dose-dependent association between low preoperative BP values and increased postoperative mortality in the elderly. In the whole population, elevated diastolic, not systolic, BP was associated with increased mortality.

Beta-blockers in noncardiac surgery: Did observational studies put us back on safe ground?

Based on landmark trials, international guidelines had for years promoted the use of beta-blockers in the setting of non-cardiac surgery. In 2011, concerns were raised regarding the integrity of some of the landmark trials, as the Dutch Erasmus Medical Center found some of them to be scientifically incorrect. Based on the remaining studies that were to be trusted, investigations showed that, in contrast to prior beliefs, the widespread use of perioperative beta-blockers might be harmful. A call for further investigations into the matter ushered in several observational studies evaluating the safety of perioperative beta-blocker therapy in specific patient subgroups. Within this review, we discuss important aspects for making these decisions, and compare the major observational studies and specific estimates of risk in subgroups of interest. We conclude that patients at high risk with heavy co-morbidities, such as heart failure, may benefit from beta-blocker therapy, whereas low-risk patients, such as patients with uncomplicated hypertension, may be at increased risk with beta-blocker therapy. We provide a critical review of current perioperative guidelines in view of the new observational data, suggesting that the recommended schematics, such as the Revised Cardiac Risk Index, for risk stratification of patients in this setting may be suboptimal. Further, we provide discussions of other aspects, including risk of sepsis, type of beta-blocker, and the potential of perioperative beta-blocker withdrawal, which may be important in guiding future studies. Summarising the current evidence, we argue that, after a precarious decade, we may just now, be back on safe ground.

Perspective: APOBEC mutagenesis in drug resistance and immune escape in HIV and cancer evolution

The apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like (APOBEC) mutational signature has only recently been detected in a multitude of cancers through next-generation sequencing. In contrast, APOBEC has been a focus of virology research for over a decade. Many lessons learnt regarding APOBEC within virology are likely to be applicable to cancer. In this review, we explore the parallels between the role of APOBEC enzymes in HIV and cancer evolution. We discuss data supporting the role of APOBEC mutagenesis in creating HIV genome heterogeneity, drug resistance, and immune escape variants. We hypothesize similar functions of APOBEC will also hold true in cancer.

Impact of Outpatient Neuraminidase Inhibitor Treatment in Patients Infected With Influenza A(H1N1)pdm09 at High Risk of Hospitalization: An Individual Participant Data Metaanalysis

Background.

While evidence exists to support the effectiveness of neuraminidase inhibitors (NAIs) in reducing mortality when given to hospitalized patients with A(H1N1)pdm09 virus infection, the impact of outpatient treatment on hospitalization has not been clearly established. We investigated the impact of outpatient NAI treatment on subsequent hospitalization in patients with A(H1N1)pdm09 virus infection.

Methods.

We assembled general community and outpatient data from 9 clinical centers in different countries collected between January 2009 and December 2010. We standardized data from each study center to create a pooled dataset and then used mixed-effects logistic regression modeling to determine the effect of NAI treatment on hospitalization. We adjusted for NAI treatment propensity and preadmission antibiotic use, including “study center” as a random intercept to account for differences in baseline hospitalization rate between centers.

Results.

We included 3376 patients with influenza A(H1N1)pdm09, of whom 3085 (91.4%) had laboratory-confirmed infection. Eight hundred seventy-three patients (25.8%) received outpatient or community-based NAI treatment, 928 of 2395 (38.8%) with available data had dyspnea or respiratory distress, and hospitalizations occurred in 1705 (50.5%). After adjustment for preadmission antibiotics and NAI treatment propensity, preadmission NAI treatment was associated with decreased odds of hospital admission compared to no NAI treatment (adjusted odds ratio, 0.24; 95% confidence interval, 0.20–0.30).

Conclusions.

In a population with confirmed or suspected A(H1N1)pdm09 and at high risk of hospitalization, outpatient or community-based NAI treatment significantly reduced the likelihood of requiring hospital admission. These data suggest that community patients with severe influenza should receive NAI treatment.