Derivation and External Validation of the Ottawa Bloodstream Infection Model for Acutely Ill Adults.

BACKGROUND: Knowing the probability that patients have a bloodstream infection (BSI) could influence the ordering of blood cultures and interpretation of their preliminary results. Many previous BSI probability models have limited applicability and accuracy. This study used currently recommended modeling techniques and a large sample to derive and validate the Ottawa BSI Model. METHODS: At a tertiary care teaching hospital, we retrieved a random sample of 4180 adults having blood cultures in our emergency department or during the initial 48 h of the encounter. Variable selection was based on clinical experience and a systematic review of previous model performance. Model performance was measured in a temporal external validation group of 4680 patients. RESULTS: A total of 327 derivation patients had a BSI (8.0%). BSI risk increased with increased number of culture sets (2 sets: adjusted odds ratio [aOR] 1.52 [1.10-2.11]; 3 sets: 1.99 [0.86-4.58]); with indwelling catheter (aOR 2.07 [1.34-3.20); with increasing temperature, heart rate, and neutrophil-lymphocyte ratio; and with decreasing systolic blood pressure, platelet count, urea-creatinine ratio, and estimated glomerular filtration rate. In the temporal external validation group, model discrimination was good (c-statistic 0.71 [0.69-0.74]) and calibration was very good (integrated calibration index .016 [.010-.024]). Exclusion of validation patients with acute SARS-CoV-2 infection improved discrimination slightly (c-statistic 0.73 [0.69-0.76]). CONCLUSIONS: The Ottawa BSI Model uses commonly available data to return an expected BSI probability for acutely ill patients. However, it cannot exclude BSI and its complexity requires computational assistance to use.

Development of the multivariate administrative data cystectomy model and its impact on misclassification bias.

BACKGROUND: Misclassification bias (MB) is the deviation of measured from true values due to incorrect case assignment. This study compared MB when cystectomy status was determined using administrative database codes vs. predicted cystectomy probability. METHODS: We identified every primary cystectomy-diversion type at a single hospital 2009-2019. We linked to claims data to measure true association of cystectomy with 30 patient and hospitalization factors. Associations were also measured when cystectomy status was assigned using billing codes and by cystectomy probability from multivariate logistic regression model with covariates from administrative data. MB was the difference between measured and true associations. RESULTS: 500 people underwent cystectomy (0.12% of 428 677 hospitalizations). Sensitivity and positive predictive values for cystectomy codes were 97.1% and 58.6% for incontinent diversions and 100.0% and 48.4% for continent diversions, respectively. The model accurately predicted cystectomy-incontinent diversion (c-statistic [C] 0.999, Integrated Calibration Index [ICI] 0.000) and cystectomy-continent diversion (C:1.000, ICI 0.000) probabilities. MB was significantly lower when model-based predictions was used to impute cystectomy-diversion type status using for both incontinent cystectomy (F = 12.75; p < .0001) and continent cystectomy (F = 11.25; p < .0001). CONCLUSIONS: A model using administrative data accurately returned the probability that cystectomy by diversion type occurred during a hospitalization. Using this model to impute cystectomy status minimized MB. Accuracy of administrative database research can be increased by using probabilistic imputation to determine case status instead of individual codes.

Barriers and facilitators to participation in exercise prehabilitation before cancer surgery for older adults with frailty: a qualitative study.

BACKGROUND: Older adults with frailty are at an increased risk of adverse outcomes after surgery. Exercise before surgery (exercise prehabilitation) may reduce adverse events and improve recovery after surgery. However, adherence with exercise therapy is often low, especially in older populations. The purpose of this study was to qualitatively assess the barriers and facilitators to participating in exercise prehabilitation from the perspective of older people with frailty participating in the intervention arm of a randomized trial. METHODS: This was a research ethics approved, nested descriptive qualitative study within a randomized controlled trial of home-based exercise prehabilitation vs. standard care with older patients (≥ 60 years) having elective cancer surgery, and who were living with frailty (Clinical Frailty Scale ≥ 4). The intervention was a home-based prehabilitation program for at least 3 weeks before surgery that involved aerobic activity, strength and stretching, and nutritional advice. After completing the prehabilitation program, participants were asked to partake in a semi-structured interview informed by the Theoretical Domains Framework (TDF). Qualitative analysis was guided by the TDF. RESULTS: Fifteen qualitative interviews were completed. Facilitators included: 1) the program being manageable and suitable to older adults with frailty, 2) adequate resources to support engagement, 3) support from others, 4) a sense of control, intrinsic value, noticing progress and improving health outcomes and 5) the program was enjoyable and facilitated by previous experience. Barriers included: 1) pre-existing conditions, fatigue and baseline fitness, 2) weather, and 3) guilt and frustration when unable to exercise. A need for individualization and variety was offered as a suggestion by participants and was therefore described as both a barrier and facilitator. CONCLUSIONS: Home-based exercise prehabilitation is feasible and acceptable to older people with frailty preparing for cancer surgery. Participants identified that a home-based program was manageable, easy to follow with helpful resources, included valuable support from the research team, and they reported self-perceived health benefits and a sense of control over their health. Future studies and implementation should consider increased personalization based on health and fitness, psychosocial support and modifications to aerobic exercises in response to adverse weather conditions.

The risk of death or unplanned readmission after discharge from a COVID-19 hospitalization in Alberta and Ontario.

BACKGROUND: The frequency of readmissions after COVID-19 hospitalizations is uncertain, as is whether current readmission prediction equations are useful for discharge risk stratification of COVID-19 survivors or for comparing among hospitals. We sought to determine the frequency and predictors of death or unplanned readmission after a COVID-19 hospital discharge. METHODS: We conducted a retrospective cohort study of all adults (≥ 18 yr) who were discharged alive from hospital after a nonpsychiatric, nonobstetric, acute care admission for COVID-19 between Jan. 1, 2020, and Sept. 30, 2021, in Alberta and Ontario. RESULTS: Of 843 737 individuals who tested positive for SARS-CoV-2 by reverse transcription polymerase chain reaction during the study period, 46 412 (5.5%) were adults admitted to hospital within 14 days of their positive test. Of these, 8496 died in hospital and 34 846 were discharged alive (30 336 discharged after an index admission of ≤ 30 d and 4510 discharged after an admission > 30 d). One in 9 discharged patients died or were readmitted within 30 days after discharge (3173 [10.5%] of those with stay ≤ 30 d and 579 [12.8%] of those with stay > 30 d). The LACE score (length of stay, acuity, Charlson Comorbidity Index and number of emergency visits in previous 6 months) for predicting urgent readmission or death within 30 days had a c-statistic of 0.60 in Alberta and 0.61 in Ontario; inclusion of sex, discharge locale, deprivation index and teaching hospital status in the model improved the c-statistic to 0.73. INTERPRETATION: Death or readmission after discharge from a COVID-19 hospitalization is common and had a similar frequency in Alberta and Ontario. Risk stratification and interinstitutional comparisons of outcomes after hospital admission for COVID-19 should include sex, discharge locale and socioeconomic measures, in addition to the LACE variables.

Association of antibiotic allergy labels with hospital length of stay.

BACKGROUND: Many antibiotic allergy labels (AAL) are invalid. Excluding true allergy in people with AAL ("delabeling") could improve health outcomes and decrease costs. Several studies with limited covariate adjustment have associated AAL with a prolonged hospital length of stay (LOS). OBJECTIVE: This study determined whether AAL's association with LOS persisted after extensive adjustment for potential confounders and covariates. METHODS: All nonpsychiatric admissions to a tertiary care teaching hospital from 2012 to 2015 were included. Generalized estimating equation methods were used to model the daily discharge likelihood as a function of AAL and other important factors (death risk score, daily discharge score, daily severity of illness score, antibiotic use, hospital day and location, weekend-holiday status, and service). RESULTS: A total of 111,611 admissions (76,460 patients) were studied, in which 16,489 (14.8%) had recorded AAL. Patients with an AAL had a notably greater disease burden: they were older and had more comorbidities, greater health system utilization, and higher death risk. In the univariate analysis, AAL was associated with a significantly decreased daily discharge likelihood (odds ratio [OR], 0.93; [95% confidence interval, 0.90-0.95]). After adjustment for potential confounders and covariates, AAL was not associated with daily discharge likelihood (adjusted OR [aOR] without antibiotics: 1.00 [0.98-1.03]; aOR with antibiotics: 1.02 [0.99-1.04]). Similar results were also seen with penicillin AAL (aOR without antibiotics: 0.99 [0.95-1.02]; aOR with antibiotics: 1.00 [0.96-1.03]). CONCLUSION: Antibiotic allergy label was strongly associated with a greater disease burden. After adjusting for important covariates, our analysis found no significant association between AAL and hospital LOS.

Derivation and external validation of a 30-day mortality risk prediction model for older patients having emergency general surgery.

BACKGROUND: Older people (≥65 yr) are at increased risk of morbidity and mortality after emergency general surgery. Risk prediction models are needed to guide decision making in this high-risk population. Existing models have substantial limitations and lack external validation, potentially limiting their applicability in clinical use. We aimed to derive and validate, both internally and externally, a multivariable model to predict 30-day mortality risk in older patients undergoing emergency general surgery. METHODS: After protocol publication, we used the National Surgical Quality Improvement Program (NSQIP) database (2012-6; estimated to contain 90% data from the USA and 10% from Canada) to derive and internally validate a model to predict 30-day mortality for older people having emergency general surgery using logistic regression with elastic net regularisation. Internal validation was done with 10-fold cross-validation. External validation was done using a temporally separate health administrative database exclusively from Ontario, Canada. RESULTS: Overall, 6012 (12.0%) of the 50 221 patients died within 30 days. The model demonstrated strong discrimination (area under the curve [AUC]=0.871) and calibration across the spectrum of observed and predicted risks. Ten-fold internal cross-validation demonstrated minimal optimism (AUC=0.851, optimism 0.019 [standard deviation=0.06]) with excellent calibration. External validation demonstrated lower discrimination (AUC=0.700) and degraded calibration. CONCLUSION: A multivariable mortality risk prediction model was strongly discriminative and well calibrated internally. However, poor external validation suggests the model may not be generalisable to non-NSQIP data and hospitals. The findings highlight the importance of external validation before clinical application of risk models.

Home-based prehabilitation with exercise to improve postoperative recovery for older adults with frailty having cancer surgery: the PREHAB randomised clinical trial.

BACKGROUND: Frailty is a state of vulnerability as a result of decreased reserves. Prehabilitation may increase reserve and improve postoperative outcomes. Our objective was to determine if home-based prehabilitation improves postoperative functional recovery in older adults with frailty having cancer surgery. METHODS: This double blind randomised trial enrolled people ≥60 yr having elective cancer surgery and ≥3 weeks from enrolment to surgery as eligible. Participation in a remotely supported, home-based exercise prehabilitation program plus nutritional guidance was compared with standard care plus written advice on age-appropriate activity and nutrition. The primary outcome was 6-min walk test (6MWT) distance at the first postoperative clinic visit. Secondary outcomes included physical performance, quality of life, disability, length of stay, non-home discharge, and 30-day readmission. RESULTS: Of 543 patients assessed, 254 were eligible and 204 (80%) were randomised (102 per arm); 182 (94 intervention and 88 control) had surgery and were analysed. Mean age was 74 yr and 57% were female. Mean duration of participation was 5 weeks, mean adherence was 61% (range 0%-100%). We found no significant difference in 6MWT at follow-up (+14 m, 95% confidence interval -26-55 m, P=0.486), or for secondary outcomes. Analyses using a prespecified adherence definition of ≥80% supported improvements in 6MWT distance, complication count, and disability. CONCLUSIONS: A home-based prehabilitation program did not significantly improve postoperative recovery or other outcomes in older adults with frailty having cancer surgery. Program adherence may be a key mediator of prehabilitation efficacy. CLINICAL TRIAL REGISTRATION: NCT02934230.

Development and evaluation of an evidence-based, theory-grounded online Clinical Frailty Scale tutorial.

INTRODUCTION: Frailty is a robust predictor of adverse outcomes in older people. Practice guidelines recommend routine screening for frailty; however, this does not occur regularly. The Clinical Frailty Scale (CFS) is a validated, feasible instrument that can be used in a variety of clinical settings and is associated with many adverse outcomes. Our objective was to develop and evaluate an online training module to guide frailty assessment using the CFS. METHODS: A multidisciplinary team of clinical experts developed an evidence-based, theory-grounded online training module for users who wished to perform frailty assessment using the CFS. The module was prospectively evaluated for user satisfaction, effectiveness and feasibility using a standardised questionnaire. Qualitative feedback was analysed with thematic analysis. RESULTS: Version 1 of the CFS module was used 627 times from 21 October 2019 to 24 March 2020. Satisfaction, effectiveness and feasibility of the module were positively rated (≥4/5 on a 5-point Likert scale n = 582 [93%], n = 507, [81%], n = 575, [91%], respectively). Qualitative feedback highlighted ease of use, likelihood of users to share the module with others and opportunities to increase multimedia content. CONCLUSION: An online tutorial, designed using evidence and theory to guide frailty assessment using the CFS, was positively rated by users. The module's content and structure was rated effective and feasible, and users were satisfied with, and likely to share, the module. Research evaluating the module's impact on the accuracy of frailty assessment is required.

Positive Predictive Value of Primary Subarachnoid Hemorrhage Diagnoses on Death Certificates.

PURPOSE: Epidemiological studies of primary subarachnoid hemorrhage (pSAH) frequently include population-based death registries for case finding. The positive predictive value of pSAH diagnoses in death registries is unknown. METHODS: This cross-sectional study identified all people in Ontario, Canada with pSAH listed as a cause of death between 2013 and 2017. pSAH was classified as "very likely" if diagnosis of pSAH was confirmed by autopsy, there was a previous hospitalization where pSAH probability exceeded 85% or death was preceded within a week by an emergency room visit where pSAH probability exceeded 25%. pSAH was classified as "very unlikely" if previous cerebrovascular imaging had never been done. Remaining cases were classified as "pSAH status unknown". RESULTS: 1,613 deaths attributed to pSAH were identified (mean 322/year). pSAH classification frequencies were as follows: very likely 528 (32.7%); very unlikely 433 (26.8%); and status unknown 652 (40.4%). CONCLUSION: We found that a quarter of pSAH cases in our province's death registry were very unlikely to be true pSAH while 40% had unknown veracity. These data should be considered when using death registries for pSAH case finding.

Shape of the association between preoperative hemoglobin level and postoperative outcomes in patients undergoing primary arthroplasty.

BACKGROUND: The shape of the association between preoperative hemoglobin level and outcomes after primary arthroplasty has not been adequately described. This study aimed to characterize the association between preoperative hemoglobin level and important outcomes after primary hip and knee arthroplasty and how this association is influenced by other key confounders. METHODS: Using de-identified, population-based health administrative data for Ontario housed at ICES, we identified all primary hip and knee arthroplasty procedures performed in Ontario between April 2007 and March 2017. Preoperative hemoglobin level, age, sex, Charlson Comorbidity Index score, American Society of Anesthesiologists score, preadmission living status, Hospital-patient One-year Mortality Risk (HOMR) score, and serum sodium and creatinine levels were extracted. All relevant postoperative outcomes that could be measured accurately were identified. We performed multivariable logistic regression and restricted cubic splines analyses. RESULTS: A total of 188 176 patients clustered within 532 surgeons were studied. The adjusted likelihood of transfusion increased notably and progressively when the preoperative hemoglobin level was below 135 g/L; duration of surgery, patient age and HOMR score amplified this association. Risk of postoperative admission to critical care showed a linear association with preoperative hemoglobin level. Risks of unplanned 30-day emergency department visit, 30-day readmission and 1-year all-cause mortality showed curvilinear associations with baseline hemoglobin level, with risks being notably greater as the level deviated from 137 g/L to 141 g/L. CONCLUSION: Preoperative hemoglobin levels, both high and low, were independently significantly associated with primary arthroplasty outcomes, and levels at which outcome risks started to increase exceeded threshold values commonly used to define "normal." Preoperative hemoglobin level should be considered in future bundled payment models that aim to account for case-mix when grading postarthroplasty outcomes.

Accuracy of Administrative Database Algorithms for Hospitalized Pneumonia in Adults: a Systematic Review.

BACKGROUND: Administrative data algorithms (ADAs) to identify pneumonia cases are commonly used in the analysis of pneumonia burden, trends, etiology, processes of care, outcomes, health care utilization, cost, and response to preventative and therapeutic interventions. However, without a good understanding of the validity of ADAs for pneumonia case identification, an adequate appreciation of this literature is difficult. We systematically reviewed the quality and accuracy of published ADAs to identify adult hospitalized pneumonia cases. METHODS: We reviewed the Medline, EMBase, and Cochrane Central databases through May 2020. All studies describing ADAs for adult hospitalized pneumonia and at least one accuracy statistic were included. Investigators independently extracted information about the sampling frame, reference standard, ADA composition, and ADA accuracy. RESULTS: Thirteen studies involving 24 ADAs were analyzed. Compliance with a 38-item study-quality assessment tool ranged from 17 to 29 (median, 23; interquartile range [IQR], 20 to 25). Study setting, design, and ADA composition varied extensively. Inclusion criteria of most studies selected for high-risk populations and/or increased pneumonia likelihood. Reference standards with explicit criteria (clinical, laboratorial, and/or radiographic) were used in only 4 ADAs. Only 2 ADAs were validated (one internally and one externally). ADA positive predictive values ranged from 35.0 to 96.5% (median, 84.8%; IQR, 65.3 to 89.1%). However, these values are exaggerated for an unselected patient population because pneumonia prevalences in the study cohorts were very high (median, 66%; IQR, 46 to 86%). ADA sensitivities ranged from 31.3 to 97.8% (median, 65.1%; IQR 52.5-72.4). DISCUSSION: ADAs for identification of adult pneumonia hospitalizations are highly heterogeneous, poorly validated, and at risk for misclassification bias. Greater standardization in reporting ADA accuracy is required in studies using pneumonia ADA for case identification so that results can be properly interpreted.

Derivation and Internal Validation of a Model to Predict the Probability of Severe Acute Respiratory Syndrome Coronavirus-2 Infection in Community People.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19 disease. There are concerns regarding limited testing capacity and the exclusion of cases from unproven screening criteria. Knowing COVID-19 risks can inform testing. This study derived and assessed a model to predict risk of SARS-CoV-2 in community-based people. METHODS: All people presenting to a community-based COVID-19 screening center answered questions regarding symptoms, possible exposure, travel, and occupation. These data were anonymously linked to SARS-CoV-2 testing results. Logistic regression was used to derive a model to predict SARS-CoV-2 infection. Bootstrap sampling evaluated the model. RESULTS: A total of 9172 consecutive people were studied. Overall infection rate was 6.2% but this varied during the study period. SARS-CoV-2 infection likelihood was primarily influenced by contact with a COVID-19 case, fever symptoms, and recent case detection rates. Internal validation found that the SARS-CoV-2 Risk Prediction Score (SCRiPS) performed well with good discrimination (c-statistic 0.736, 95%CI 0.715-0.757) and very good calibration (integrated calibration index 0.0083, 95%CI 0.0048-0.0131). Focusing testing on people whose expected SARS-CoV-2 risk equaled or exceeded the recent case detection rate would increase the number of identified SARS-CoV-2 cases by 63.1% (95%CI 54.5-72.3). CONCLUSION: The SCRiPS model accurately estimates the risk of SARS-CoV-2 infection in community-based people undergoing testing. Using SCRiPS can importantly increase SARS-CoV-2 infection identification when testing capacity is limited.

Peripheral Nerve Blocks and Potentially Attributable Adverse Events in Older People with Hip Fracture: A Retrospective Population-based Cohort Study.

BACKGROUND: Peripheral nerve blocks are being used with increasing frequency for management of hip fracture-related pain. Despite converging evidence that nerve blocks may be beneficial, safety data are lacking. This study hypothesized that peripheral nerve block receipt would not be associated with adverse events potentially attributable to nerve blocks, as well as overall patient safety incidents while in hospital. METHODS: This was a preregistered, retrospective population-based cohort study using linked administrative data. This study identified all hip fracture admissions in people 50 yr of age or older and identified all nerve blocks (although we were unable to ascertain the specific anatomic location or type of block), potentially attributable adverse events (composite of seizures, fall-related injuries, cardiac arrest, nerve injury), and any patient safety events using validated codes. The study also estimated the unadjusted and adjusted association of nerve blocks with adverse events; adjusted absolute risk differences were also calculated. RESULTS: In total, 91,563 hip fracture patients from 2009 to 2017 were identified; 15,631 (17.1%) received a nerve block, and 5,321 (5.8%; 95% CI, 5.7 to 6.0%) patients experienced a potentially nerve block-attributable adverse event: 866 (5.5%) in patients with a block and 4,455 (5.9%) without a block. Before and after adjustment, nerve blocks were not associated with potentially attributable adverse events (adjusted odds ratio, 1.05; 95% CI, 0.97 to 1.15; and adjusted risk difference, 0.3%, 95% CI, -0.1 to 0.8). CONCLUSIONS: The data suggest that nerve blocks in hip fracture patients are not associated with higher rates of potentially nerve block-attributable adverse events, although these findings may be influenced by limitations in routinely collected administrative data.

A Bayesian Comparison of Frailty Instruments in Noncardiac Surgery: A Cohort Study.

BACKGROUND: Frailty-a multidimensional syndrome related to age- and disease-related deficits-is a key risk factor for older surgical patients. However, it is unknown which frailty instrument most accurately predicts postoperative outcomes. Our objectives were to quantify the probability of association and relative predictive performance of 2 frailty instruments (ie, the risk analysis index-administrative [RAI-A] and 5-item modified frailty index [mFI-5]) with postoperative outcomes in National Surgical Quality Improvement Program (NSQIP) data. METHODS: Retrospective cohort study using Bayesian analysis of NSQIP hospitals. Adults having inpatient small or large bowel surgery 2010-2015 (derivation cohort) or intermediate to high risk mixed noncardiac surgery in 2016 (validation cohort) had preoperative frailty assigned using 2 unique approaches (RAI-A and mFI-5). Probabilities of association were calculated based on posterior distributions and relative predictive performance using posterior predictive distributions and Bayes factors for 30-day mortality (primary outcome) and serious complications (secondary outcome). RESULTS: Of 50,630 participants, 7630 (14.0%) died and 19,545 (38.6%) had a serious complication. Without adjustment, the RAI-A and mFI-5 had >99% probability being associated with mortality with a ≥2.0 odds ratio (ie, large effect size). After adjustment for NSQIP risk calculator variables, only the RAI-A had ≥95% probability of a nonzero association with mortality. Similar results arose when predicting postoperative complications. The RAI-A provided better predictive accuracy for mortality than the mFI-5 (minimum Bayes factor 3.25 × 1014), and only the RAI-A improved predictive accuracy beyond that of the NSQIP risk calculator (minimum Bayes factor = 4.27 × 1013). Results were consistent in leave-one-out cross-validation. CONCLUSIONS: Translation of frailty-related findings from research and quality improvement studies to clinical care and surgical planning will be aided by a consistent approach to measuring frailty with a multidimensional instrument like RAI-A, which appears to be superior to the mFI-5 when predicting outcomes for inpatient noncardiac surgery.

Frailty as a Predictor of Death or New Disability After Surgery: A Prospective Cohort Study.

OBJECTIVE: To compare the accuracy of the modified Fried Index (mFI) and the Clinical Frailty Scale (CFS) to predict death or patient-reported new disability 90 days after major elective surgery. BACKGROUND: The association of frailty with patient-reported outcomes, and comparisons between preoperative frailty instruments are poorly described. METHODS: This was a prospective multicenter cohort study. We determined frailty status in individuals ≥65 years having elective noncardiac surgery using the mFI and CFS. Outcomes included death or patient-reported new disability (primary); safety incidents, length of stay (LOS), and institutional discharge (secondary); ease of use, usefulness, benefit, clinical importance, and feasibility (tertiary). We measured the adjusted association of frailty with outcomes using regression analysis and compared true positive and false positive rates (TPR/FPR). RESULTS: Of 702 participants, 645 had complete follow up. The CFS identified 297 (42.3%) with frailty, the mFI 257 (36.6%); 72 (11.1%) died or experienced a new disability. Frailty was significantly associated with the primary outcome (CFS adjusted odds ratio, OR, 2.51, 95% confidence interval, CI, 1.50-4.21; mFI adjusted-OR 2.60, 95% CI 1.57-4.31). TPR and FPR were not significantly different between instruments. Frailty was the only significant predictor of death or new disability in a multivariable analysis. Need for institutional discharge, costs and LOS were significantly increased in individuals with frailty. The CFS was easier to use, required less time and had less missing data. CONCLUSIONS: Older people with frailty are significantly more likely to die or experience a new patient-reported disability after surgery. Clinicians performing frailty assessments before surgery should consider the CFS over the mFI as accuracy was similar, but ease of use and feasibility were higher.

Criteria for Hyponatremic Overcorrection: Systematic Review and Cohort Study of Emergently Ill Patients.

BACKGROUND: Hyponatremia is the most common electrolyte disturbance amongst hospitalized patients. An overly rapid rate of correction of chronic hyponatremia is believed to increase the risk of poor clinical outcomes including osmotic demyelination syndrome (ODS). There is disagreement in the literature regarding the definition of hyponatremic overcorrection. METHODS: We performed a systematic review of all English language studies to identify those that calculated sodium correction rate and classified patients' overcorrection status. We then identified all patients who presented to our hospital's emergency department between 2003 and 2015 with a corrected serum sodium ≤ 116 mmol/L. All methods from the systematic review for sodium correction rate calculation and overcorrection status were applied to this cohort. RESULTS: We identified 24 studies citing 9 distinct sodium correction rate methods and 14 criteria for overcorrection. Six hundred twenty-four patients presenting with severe hyponatremia (median initial value 113 mMol) were identified. Depending on the method used, the median sodium correction rates in our cohort ranged from 0.271 to 1.13 mmol/L per hour. The proportion of patients classified with overcorrection with the different criteria varied almost 11-fold, ranging from 8.5 to 89.9%. CONCLUSION: Published methods disagree regarding the calculation of sodium correction rates and the definition of hyponatremic overcorrection. This leads to wide variations in sodium correction rates and the prevalence of overcorrection in patient cohorts. Definitions based on ODS risk are needed.

Frailty and long-term postoperative disability trajectories: a prospective multicentre cohort study.

BACKGROUND: Frailty is associated with early postoperative outcomes. How frailty influences long-term postoperative recovery is poorly described. Our objective was to evaluate the association of frailty with postoperative disability trajectories in the year after surgery. METHODS: Prespecified 1-yr follow-up of a prospective multicentre cohort study. Patients ≥65 yr were assessed for frailty before major elective noncardiac surgery (Clinical Frailty Scale [CFS] and Fried Phenotype [FP]). The primary outcome was patient-reported disability score (using the WHO Disability Assessment Schedule 2.0) at baseline, 30, 90, and 365 days after surgery. Repeated measures linear regression estimated the association of preoperative frailty with changes in disability scores over time, adjusted for procedure. Group-based trajectory modelling was used to identify subgroup trajectories of people with frailty. RESULTS: One-year follow-up was complete for 687/702 (97.9%) participants. Frailty was associated with a significant difference in disability trajectory (P<0.0001). Compared with baseline, people with frailty experienced a decrease in disability score at 365 days (CFS frailty: -7.3 points, 95% confidence interval [CI] -10.2 to -4.5); (FP frailty: -5.4 points, 95% CI -8.5 to -2.3); people without frailty had no significant change in their disability score from baseline (no CFS frailty: +0.8 points, 95% CI -1.7 to 3.2; no FP frailty: +1.1 points, 95% CI -3.5 to 1.3). More than one-third of people with frailty experienced an early increase in disability before achieving a net decrease in disability. CONCLUSIONS: Decision-making and care planning should integrate the possible trade-offs between early adverse outcomes with longer-term benefit when frailty is present in older surgical patients.

Prospective Comparison of Preoperative Predictive Performance Between 3 Leading Frailty Instruments.

BACKGROUND: Guidelines recommend routine preoperative frailty assessment for older people. However, the degree to which frailty instruments improve predictive accuracy when added to traditional risk factors is poorly described. Our objective was to measure the accuracy gained in predicting outcomes important to older patients when adding the Clinical Frailty Scale (CFS), Fried Phenotype (FP), or Frailty Index (FI) to traditional risk factors. METHODS: This was an analysis of a multicenter prospective cohort of elective noncardiac surgery patients ≥65 years of age. Each frailty instrument was prospectively collected. The added predictive performance of each frailty instrument beyond the baseline model (age, sex, American Society of Anesthesiologists' score, procedural risk) was estimated using likelihood ratio test, discrimination, calibration, explained variance, and reclassification. Outcomes analyzed included death or new disability, prolonged length of stay (LoS, >75th percentile), and adverse discharge (death or non-home discharge). RESULTS: We included 645 participants (mean age, 74 [standard deviation, 6]); 72 (11.2%) participants died or experienced a new disability, 164 (25.4%) had prolonged LoS, and 60 (9.2%) had adverse discharge. Compared to the baseline model predicting death or new disability (area under the curve [AUC], 0.67; R, 0.08, good calibration), prolonged LoS (AUC, 0.73; R, 0.18, good calibration), and adverse discharge (AUC, 0.78; R, 0.16, poor calibration), the CFS improved fit per the likelihood ratio test (P < .02 for death or new disability, <.001 for LoS, <.001 for discharge), discrimination (AUC = 0.71 for death or new disability, 0.76 for LoS, 0.82 for discharge), calibration (good for death or new disability, LoS, and discharge), explained variance (R = 0.11 for death or new disability, 0.22 for LoS, 0.25 for discharge), and reclassification (appropriate directional reclassification) for all outcomes. The FP improved discrimination and R for all outcomes, but to a lesser degree than the CFS. The FI improved discrimination for death or new disability and R for all outcomes, but to a lesser degree than the CFS and the FP. These results were consistent in internal validation. CONCLUSIONS: Frailty instruments provide meaningful increases in accuracy when predicting postoperative outcomes for older people. Compared to the FP and FI, the CFS appears to improve all measures of predictive performance to the greatest extent and across outcomes. Combined with previous research demonstrating that the CFS is easy to use and requires less time than the FP, clinicians should consider its use in preoperative practice.

Evaluation of a preoperative personalized risk communication tool: a prospective before-and-after study.

PURPOSE: Patients want personalized information before surgery; most do not receive personalized risk estimates. Inadequate information contributes to poor experience and medicolegal complaints. We hypothesized that exposure to the Personalized Risk Evaluation and Decision Making in Preoperative Clinical Assessment (PREDICT) app, a personalized risk communication tool, would improve patient knowledge and satisfaction after anesthesiology consultations compared with standard care. METHODS: We conducted a prospective clinical study (before-after design) and used patient-reported data to calculate personalized risks of morbidity, mortality, and expected length of stay using a locally calibrated National Surgical Quality Improvement Program risk calculator embedded in the PREDICT app. In the standard care (before) phase, the application's materials and output were not available to participants; in the PREDICT app (after) phase, personalized risks were communicated. Our primary outcome was knowledge score after the anesthesiology consultation. Secondary outcomes included patient satisfaction, anxiety, feasibility, and acceptability. RESULTS: We included 183 participants (90 before; 93 after). Compared with standard care phase, the PREDICT app phase had higher post-consultation: knowledge of risks (14.3% higher; 95% confidence interval [CI], 6.5 to 22.0; P < 0.001) and satisfaction (0.8 points; 95% CI, 0.1 to 1.4; P = 0.03). Anxiety was unchanged (- 1.9%; 95% CI, - 4.2 to 0.5; P = 0.13). Acceptability was high for patients and anesthesiologists. CONCLUSION: Exposure to a patient-facing, personalized risk communication app improved knowledge of personalized risk and increased satisfaction for adults before elective inpatient surgery. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT03422133); registered 5 February 2018.

RéSUMé: OBJECTIF: Les patients veulent disposer d'informations personnalisées avant leur chirurgie, mais la plupart d'entre eux ne reçoivent pas d'estimations de leur risque personnalisées. Des informations inadéquates contribuent à une mauvaise expérience et à des plaintes médicolégales. Nous avons émis l'hypothèse qu'une exposition à l'application PREDICT (Personalized Risk Evaluation and Decision Making in Preoperative Clinical Assessment), un outil de communication du risque personnalisé, améliorerait les connaissances et la satisfaction des patients après leurs consultations en anesthésiologie comparativement à des soins standard. MéTHODE: Nous avons réalisé une étude clinique prospective (de type avant-après) et utilisé les données rapportées par les patients afin de calculer leur risque personnalisé de morbidité et de mortalité, ainsi que la durée de séjour anticipée à l'aide d'un calculateur de risque tiré du Programme national d'amélioration de la qualité chirurgicale que nous avons calibré localement et intégré à l'application PREDICT. Dans la phase de soins standard (avant), le contenu et les résultats de l'application n'étaient pas divulgués aux participants; dans la phase comportant l'application PREDICT (après), les risques personnalisés étaient communiqués. Notre critère d'évaluation principal était le score des connaissances des patients après la consultation en anesthésiologie. Les critères d'évaluation secondaires comprenaient la satisfaction des patients et leur niveau d'anxiété ainsi que la faisabilité et l'acceptabilité d'une telle approche. RéSULTATS: Nous avons inclus 183 participants (90 avant; 93 après). Comparativement à la phase de soins standard, la phase avec l'application PREDICT a démontré un niveau plus élevé de connaissances des risques post consultation (14,3 % plus élevé; intervalle de confiance [IC] 95 %, 6,5 à 22,0; P < 0,001) et de satisfaction (0,8 point; IC 95 %, 0,1 à 1,4; P = 0,03). L'anxiété est demeurée inchangée (− 1,9 %; IC 95 %, − 4,2 à 0,5; P = 0,13). L'acceptabilité était élevée, tant chez les patients que chez les anesthésiologistes. CONCLUSION: L'exposition des patients à une application de communication du risque personnalisé a amélioré leurs connaissances de leur risque personnalisé et augmenté la satisfaction des adultes avant une chirurgie non urgente et non ambulatoire. ENREGISTREMENT DE L'éTUDE: www.clinicaltrials.gov (NCT03422133); enregistrée le 5 février 2018.

Predicting 1-Year Mortality After Cardiac Surgery Complicated by Prolonged Critical Illness: Derivation and Validation of a Population-Based Risk Model.

OBJECTIVES: Patients experiencing prolonged critical illness after cardiac surgery represent a resource- intensive group with a high risk of mortality. The authors sought to derive and validate a multivariate model that accurately predicts 1-year mortality in people who have been critically ill for at least 1 week after cardiac surgery. DESIGN: This was a retrospective population-based cohort study using linked administrative data. SETTING: Eleven hospitals providing cardiac surgical care in the Canadian province of Ontario. PARTICIPANTS: All adult patients aged ≥18 years undergoing 1 of the 5 most common major cardiac surgical procedures between April 1, 2009, and March 31, 2014. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The authors' primary exposure was presence in an intensive care unit on the seventh postoperative day (POD7) and the primary outcome was all-cause mortality occurring after POD7 and within 1 year from the date of surgery. Candidate predictors included patient demographics, surgical details, preoperative medical conditions, postoperative status, and life supportive therapies utilized on POD7. Descriptive statistics were used to compare predictor variables between participants who did or did not die in the year after surgery. The prediction model was derived in the full data set using logistic regression and the prespecified set of predictor variables. A total of 2,031 individuals remained in an intensive care unit on POD7 (4.8% of all cardiac surgery patients). Five hundred twenty-one people died (25.6%) in the year after surgery; 353 died before hospital discharge (17.3% of total cohort, 67.8% of deaths). Requirement for multiple vasoactive or inotropic medications was the strongest predictor of mortality, followed by need for invasive ventilation, 3 or more preoperative comorbidities, need for a single inotropic or vasoactive medication, and requirement for dialysis before surgery. The derivation area under the curve was 0.80, and the model was well- calibrated with a Hosmer-Lemeshow p value of 0.5 and good calibration across risk deciles. CONCLUSIONS: A prespecified multivariate model using clinically relevant, routinely available variables was able to accurately predict death among those with prolonged critical illness after cardiac surgery.