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  1. Roshanov PS, Chan MTV, Borges FK, Conen D, Wang CY, Xavier D, et al.
    Anesthesiology, 2023 Sep 15.
    PMID: 37713506 DOI: 10.1097/ALN.0000000000004763
    BACKGROUND: In prior analyses, myocardial injury after noncardiac surgery, major bleeding, and sepsis were independently associated with most deaths in the 30 days after noncardiac surgery, but most of these deaths occurred during the index hospitalization for surgery. We set out to describe outcomes after discharge from hospital up to one year after inpatient noncardiac surgery and associations between pre-discharge complications and post-discharge death up to one year after surgery.

    METHODS: Analysis of patients discharged after inpatient noncardiac surgery in a large international prospective cohort study across 28 centers from 2007-2013 of patients aged ≥45 years followed to one year after surgery. We estimated 1) the cumulative post-discharge incidence of death and other outcomes up to a year after surgery and 2) the adjusted time-varying associations between post-discharge death and pre-discharge complications including myocardial injury after noncardiac surgery, major bleeding, sepsis, infection without sepsis, stroke, congestive heart failure, clinically important atrial fibrillation or flutter, amputation, venous thromboembolism, and acute kidney injury managed with dialysis.

    RESULTS: Among 38,898 patients discharged after surgery, the cumulative one-year incidence was 5.8% (95% CI, 5.5-6.0%) for all-cause death and 24.7% (24.2-25.1%) for all-cause hospital readmission. Pre-discharge complications were associated with 33.7% (27.2-40.2%) of deaths up to 30 days after discharge and 15.0% (12.0-17.9%) up to one year. Most of the association with death was due to myocardial injury after noncardiac surgery (15.6% [9.3-21.9%) of deaths within 30 days, 6.4% [4.1-8.7%] within one year), major bleeding (15.0% [8.3-21.7%] within 30 days, 4.7% [2.2-7.2%] within one year), and sepsis (5.4% [2.2-8.6%] within 30 days, 2.1% [1.0-3.1%] within one year).

    CONCLUSIONS: One in 18 patients ≥45 years old discharged after inpatient noncardiac surgery died within one year and one quarter were readmitted to hospital. The risk of death associated with pre-discharge perioperative complications persists for weeks to months after discharge.

  2. Fedoruk KA, Chan YK, Williams CE
    Int J Obstet Anesth, 2023 May;54:103639.
    PMID: 36841065 DOI: 10.1016/j.ijoa.2023.103639
    If asked to describe the term "anesthesiologist scholar", one may receive a variety of definitions depending on the individual's area of practice, location in the world, and the generation in which they trained. In this article, we review the roles of five core elements that make an anesthesiologist a "scholar": skills in critical appraisal, literature review, quality improvement, journal club participation, and presentation delivery. Although this list of scholarly components is not comprehensive, review of each element's role in the everyday practice and training of physicians will offer insight into their evolution and may offer a glimpse into the future of anesthesiologist scholars. Overall, through the dissemination, recognition, and support of scholarship through these practices, we will continue to achieve meaningful outcomes for our patients and promote a culture of collaboration worldwide. We should ensure that these topic areas become a bedrock of medical education globally, and we must foster opportunities for those who have already completed training to develop and master these skills as a part of their clinical and academic practice.
  3. Machain-Williams C, Reyes-Solis GC, Blitvich BJ, Laredo-Tiscareño V, Dzul-Rosado AR, Kim S, et al.
    Viral Immunol, 2023 Mar;36(2):101-109.
    PMID: 36862827 DOI: 10.1089/vim.2022.0110
    Dengue virus (DENV) is the etiological agent of dengue, the most important mosquito-transmitted viral disease of humans worldwide. Enzyme-linked immunosorbent assays (ELISAs) designed to detect DENV IgM are commonly used for dengue diagnosis. However, DENV IgM is not reliably detected until ≥4 days after illness onset. Reverse transcription-polymerase chain reaction (RT-PCR) can diagnose early dengue but requires specialized equipment, reagents, and trained personnel. Additional diagnostic tools are needed. Limited work has been performed to determine whether IgE-based assays can be used for the early detection of vector-borne viral diseases, including dengue. In this study, we determined the efficacy of a DENV IgE capture ELISA for the detection of early dengue. Sera were collected within the first 4 days of illness onset from 117 patients with laboratory-confirmed dengue, as determined by DENV-specific RT-PCR. The serotypes responsible for the infections were DENV-1 and DENV-2 (57 and 60 patients, respectively). Sera were also collected from 113 dengue-negative individuals with febrile illness of undetermined etiology and 30 healthy controls. The capture ELISA detected DENV IgE in 97 (82.9%) confirmed dengue patients and none of the healthy controls. There was a high false positivity rate (22.1%) among the febrile non-dengue patients. In conclusion, we provide evidence that IgE capture assays have the potential to be explored for early diagnosis of dengue, but further research is necessary to address the possible false positivity rate among patients with other febrile illnesses.
  4. Mincham G, Baldock KL, Rozilawati H, Williams CR
    Epidemiol Infect, 2019 01;147:e125.
    PMID: 30869038 DOI: 10.1017/S095026881900030X
    Dengue infection in China has increased dramatically in recent years. Guangdong province (main city Guangzhou) accounted for more than 94% of all dengue cases in the 2014 outbreak. Currently, there is no existing effective vaccine and most efforts of control are focused on the vector itself. This study aimed to evaluate different dengue management strategies in a region where this disease is emerging. This work was done by establishing a dengue simulation model for Guangzhou to enable the testing of control strategies aimed at vector control and vaccination. For that purpose, the computer-based dengue simulation model (DENSiM) together with the Container-Inhabiting Mosquito Simulation Model (CIMSiM) has been used to create a working dengue simulation model for the city of Guangzhou. In order to achieve the best model fit against historical surveillance data, virus introduction scenarios were run and then matched against the actual dengue surveillance data. The simulation model was able to predict retrospective outbreaks with a sensitivity of 0.18 and a specificity of 0.98. This new parameterisation can now be used to evaluate the potential impact of different control strategies on dengue transmission in Guangzhou. The knowledge generated from this research would provide useful information for authorities regarding the historic patterns of dengue outbreaks, as well as the effectiveness of different disease management strategies.
  5. Biccard BM, Scott DJA, Chan MTV, Archbold A, Wang CY, Sigamani A, et al.
    Ann Surg, 2018 08;268(2):357-363.
    PMID: 28486392 DOI: 10.1097/SLA.0000000000002290
    OBJECTIVE: To determine the prognostic relevance, clinical characteristics, and 30-day outcomes associated with myocardial injury after noncardiac surgery (MINS) in vascular surgical patients.

    BACKGROUND: MINS has been independently associated with 30-day mortality after noncardiac surgery. The characteristics and prognostic importance of MINS in vascular surgery patients are poorly described.

    METHODS: This was an international prospective cohort study of 15,102 noncardiac surgery patients 45 years or older, of whom 502 patients underwent vascular surgery. All patients had fourth-generation plasma troponin T (TnT) concentrations measured during the first 3 postoperative days. MINS was defined as a TnT of 0.03 ng/mL of higher secondary to ischemia. The objectives of the present study were to determine (i) if MINS is prognostically important in vascular surgical patients, (ii) the clinical characteristics of vascular surgery patients with and without MINS, (iii) the 30-day outcomes for vascular surgery patients with and without MINS, and (iv) the proportion of MINS that probably would have gone undetected without routine troponin monitoring.

    RESULTS: The incidence of MINS in the vascular surgery patients was 19.1% (95% confidence interval (CI), 15.7%-22.6%). 30-day all-cause mortality in the vascular cohort was 12.5% (95% CI 7.3%-20.6%) in patients with MINS compared with 1.5% (95% CI 0.7%-3.2%) in patients without MINS (P < 0.001). MINS was independently associated with 30-day mortality in vascular patients (odds ratio, 9.48; 95% CI, 3.46-25.96). The 30-day mortality was similar in MINS patients with (15.0%; 95% CI, 7.1-29.1) and without an ischemic feature (12.2%; 95% CI, 5.3-25.5, P = 0.76). The proportion of vascular surgery patients who suffered MINS without overt evidence of myocardial ischemia was 74.1% (95% CI, 63.6-82.4).

    CONCLUSIONS: Approximately 1 in 5 patients experienced MINS after vascular surgery. MINS was independently associated with 30-day mortality. The majority of patients with MINS were asymptomatic and would have gone undetected without routine postoperative troponin measurement.

  6. Writing Committee for the VISION Study Investigators, Devereaux PJ, Biccard BM, Sigamani A, Xavier D, Chan MTV, et al.
    JAMA, 2017 Apr 25;317(16):1642-1651.
    PMID: 28444280 DOI: 10.1001/jama.2017.4360
    Importance: Little is known about the relationship between perioperative high-sensitivity troponin T (hsTnT) measurements and 30-day mortality and myocardial injury after noncardiac surgery (MINS).

    Objective: To determine the association between perioperative hsTnT measurements and 30-day mortality and potential diagnostic criteria for MINS (ie, myocardial injury due to ischemia associated with 30-day mortality).

    Design, Setting, and Participants: Prospective cohort study of patients aged 45 years or older who underwent inpatient noncardiac surgery and had a postoperative hsTnT measurement. Starting in October 2008, participants were recruited at 23 centers in 13 countries; follow-up finished in December 2013.

    Exposures: Patients had hsTnT measurements 6 to 12 hours after surgery and daily for 3 days; 40.4% had a preoperative hsTnT measurement.

    Main Outcomes and Measures: A modified Mazumdar approach (an iterative process) was used to determine if there were hsTnT thresholds associated with risk of death and had an adjusted hazard ratio (HR) of 3.0 or higher and a risk of 30-day mortality of 3% or higher. To determine potential diagnostic criteria for MINS, regression analyses ascertained if postoperative hsTnT elevations required an ischemic feature (eg, ischemic symptom or electrocardiography finding) to be associated with 30-day mortality.

    Results: Among 21 842 participants, the mean age was 63.1 (SD, 10.7) years and 49.1% were female. Death within 30 days after surgery occurred in 266 patients (1.2%; 95% CI, 1.1%-1.4%). Multivariable analysis demonstrated that compared with the reference group (peak hsTnT <5 ng/L), peak postoperative hsTnT levels of 20 to less than 65 ng/L, 65 to less than 1000 ng/L, and 1000 ng/L or higher had 30-day mortality rates of 3.0% (123/4049; 95% CI, 2.6%-3.6%), 9.1% (102/1118; 95% CI, 7.6%-11.0%), and 29.6% (16/54; 95% CI, 19.1%-42.8%), with corresponding adjusted HRs of 23.63 (95% CI, 10.32-54.09), 70.34 (95% CI, 30.60-161.71), and 227.01 (95% CI, 87.35-589.92), respectively. An absolute hsTnT change of 5 ng/L or higher was associated with an increased risk of 30-day mortality (adjusted HR, 4.69; 95% CI, 3.52-6.25). An elevated postoperative hsTnT (ie, 20 to <65 ng/L with an absolute change ≥5 ng/L or hsTnT ≥65 ng/L) without an ischemic feature was associated with 30-day mortality (adjusted HR, 3.20; 95% CI, 2.37-4.32). Among the 3904 patients (17.9%; 95% CI, 17.4%-18.4%) with MINS, 3633 (93.1%; 95% CI, 92.2%-93.8%) did not experience an ischemic symptom.

    Conclusions and Relevance: Among patients undergoing noncardiac surgery, peak postoperative hsTnT during the first 3 days after surgery was significantly associated with 30-day mortality. Elevated postoperative hsTnT without an ischemic feature was also associated with 30-day mortality.

  7. Klionsky DJ, Abdelmohsen K, Abe A, Abedin MJ, Abeliovich H, Acevedo Arozena A, et al.
    Autophagy, 2016;12(1):1-222.
    PMID: 26799652 DOI: 10.1080/15548627.2015.1100356
  8. Williams CR, Gill BS, Mincham G, Mohd Zaki AH, Abdullah N, Mahiyuddin WR, et al.
    Epidemiol Infect, 2015 Oct;143(13):2856-64.
    PMID: 25591942 DOI: 10.1017/S095026881400380X
    We aimed to reparameterize and validate an existing dengue model, comprising an entomological component (CIMSiM) and a disease component (DENSiM) for application in Malaysia. With the model we aimed to measure the effect of importation rate on dengue incidence, and to determine the potential impact of moderate climate change (a 1 °C temperature increase) on dengue activity. Dengue models (comprising CIMSiM and DENSiM) were reparameterized for a simulated Malaysian village of 10 000 people, and validated against monthly dengue case data from the district of Petaling Jaya in the state of Selangor. Simulations were also performed for 2008-2012 for variable virus importation rates (ranging from 1 to 25 per week) and dengue incidence determined. Dengue incidence in the period 2010-2012 was modelled, twice, with observed daily weather and with a 1 °C increase, the latter to simulate moderate climate change. Strong concordance between simulated and observed monthly dengue cases was observed (up to r = 0·72). There was a linear relationship between importation and incidence. However, a doubling of dengue importation did not equate to a doubling of dengue activity. The largest individual dengue outbreak was observed with the lowest dengue importation rate. Moderate climate change resulted in an overall decrease in dengue activity over a 3-year period, linked to high human seroprevalence early on in the simulation. Our results suggest that moderate reductions in importation with control programmes may not reduce the frequency of large outbreaks. Moderate increases in temperature do not necessarily lead to greater dengue incidence.
  9. Botto F, Alonso-Coello P, Chan MT, Villar JC, Xavier D, Srinathan S, et al.
    Anesthesiology, 2014 Mar;120(3):564-78.
    PMID: 24534856 DOI: 10.1097/ALN.0000000000000113
    BACKGROUND: Myocardial injury after noncardiac surgery (MINS) was defined as prognostically relevant myocardial injury due to ischemia that occurs during or within 30 days after noncardiac surgery. The study's four objectives were to determine the diagnostic criteria, characteristics, predictors, and 30-day outcomes of MINS.

    METHODS: In this international, prospective cohort study of 15,065 patients aged 45 yr or older who underwent in-patient noncardiac surgery, troponin T was measured during the first 3 postoperative days. Patients with a troponin T level of 0.04 ng/ml or greater (elevated "abnormal" laboratory threshold) were assessed for ischemic features (i.e., ischemic symptoms and electrocardiography findings). Patients adjudicated as having a nonischemic troponin elevation (e.g., sepsis) were excluded. To establish diagnostic criteria for MINS, the authors used Cox regression analyses in which the dependent variable was 30-day mortality (260 deaths) and independent variables included preoperative variables, perioperative complications, and potential MINS diagnostic criteria.

    RESULTS: An elevated troponin after noncardiac surgery, irrespective of the presence of an ischemic feature, independently predicted 30-day mortality. Therefore, the authors' diagnostic criterion for MINS was a peak troponin T level of 0.03 ng/ml or greater judged due to myocardial ischemia. MINS was an independent predictor of 30-day mortality (adjusted hazard ratio, 3.87; 95% CI, 2.96-5.08) and had the highest population-attributable risk (34.0%, 95% CI, 26.6-41.5) of the perioperative complications. Twelve hundred patients (8.0%) suffered MINS, and 58.2% of these patients would not have fulfilled the universal definition of myocardial infarction. Only 15.8% of patients with MINS experienced an ischemic symptom.

    CONCLUSION: Among adults undergoing noncardiac surgery, MINS is common and associated with substantial mortality.

  10. Negim el-S, Kozhamzharova L, Khatib J, Bekbayeva L, Williams C
    ScientificWorldJournal, 2014;2014:942978.
    PMID: 24955426 DOI: 10.1155/2014/942978
    The physical and mechanical properties of mortar containing synthetic cosurfactants as air entraining agent are investigated. The cosurfactants consist of a combination of 2% dodecyl benzene sodium sulfonate (DBSS) and either 1.5% polyvinyl alcohol (PVA) or 1.5% polyoxyethylene glycol monomethyl ether (POE). Also these cosurfactants were used to prepare copolymers latex: styrene/butyl methacrylate (St/BuMA), styrene/methyl methacrylate (St/MMA), and styrene/glycidyl methacrylate (St/GMA), in order to study their effects on the properties of mortar. The properties of mortar examined included flow table, W/C ratio, setting time, water absorption, compressive strength, and combined water. The results indicate that the latex causes improvement in mortar properties compared with cosurfactants. Also polymer latex containing DBSS/POE is more effective than that containing DBSS/PVA.
  11. Alfred R, Ahmad AH, Payne J, Williams C, Ambu LN, How PM, et al.
    PLoS One, 2012;7(2):e31400.
    PMID: 22347469 DOI: 10.1371/journal.pone.0031400
    Home range is defined as the extent and location of the area covered annually by a wild animal in its natural habitat. Studies of African and Indian elephants in landscapes of largely open habitats have indicated that the sizes of the home range are determined not only by the food supplies and seasonal changes, but also by numerous other factors including availability of water sources, habitat loss and the existence of man-made barriers. The home range size for the Bornean elephant had never been investigated before.
  12. Williams CD, Casazza L
    Lancet, 1973 Aug 11;2(7824):318.
    PMID: 4124792 DOI: 10.1016/s0140-6736(73)90813-1
  13. Williams C
    Pediatrics, 1970 Sep;46(3):448-55.
    PMID: 5454800
  14. Williams CD
    Lancet, 1968 Oct 19;2(7573):868-9.
    PMID: 4175755
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