The Association of Intra-Abdominal Adhesions with Peritoneal Dialysis Catheter-Related Complications

BACKGROUND

This study investigated the association of intra-abdominal adhesions with the risk of peritoneal dialysis (PD) catheter complications.

METHODS

Individuals undergoing laparoscopic PD catheter insertion were prospectively enrolled from eight centers in Canada and the United States. Patients were grouped based on the presence of adhesions observed during catheter insertion. The primary outcome was the composite of PD never starting, termination of PD, or the need for an invasive procedure caused by flow restriction or abdominal pain.

RESULTS

Seven hundred and fifty-eight individuals were enrolled, of whom 201 (27%) had adhesions during laparoscopic PD catheter insertion. The risk of the primary outcome occurred in 35 (17%) in the adhesion group compared with 58 (10%) in the no adhesion group (adjusted HR, 1.64; 95% confidence interval [CI], 1.05 to 2.55) within 6 months of insertion. Lower abdominal or pelvic adhesions had an adjusted HR of 1.80 (95% CI, 1.09 to 2.98) compared with the no adhesion group. Invasive procedures were required in 26 (13%) and 47 (8%) of the adhesion and no adhesion groups, respectively (unadjusted HR, 1.60: 95% CI, 1.04 to 2.47) within 6 months of insertion. The adjusted odds ratio for adhesions for women was 1.65 (95% CI, 1.12 to 2.41), for body mass index per 5 kg/m 2 was 1.16 (95% CI, 1.003 to 1.34), and for prior abdominal surgery was 8.34 (95% CI, 5.5 to 12.34). Common abnormalities found during invasive procedures included PD catheter tip migration, occlusion of the lumen with fibrin, omental wrapping, adherence to the bowel, and the development of new adhesions.

CONCLUSIONS

People with intra-abdominal adhesions undergoing PD catheter insertion were at higher risk for abdominal pain or flow restriction preventing PD from starting, PD termination, or requiring an invasive procedure. However, most patients, with or without adhesions, did not experience complications, and most complications did not lead to the termination of PD therapy.

Impact of Prior Abdominal Procedures on Peritoneal Dialysis Catheter Outcomes: Findings From the North American Peritoneal Dialysis Catheter Registry

RATIONALE & OBJECTIVE

A history of prior abdominal procedures may influence the likelihood of referral for peritoneal dialysis (PD) catheter insertion. To guide clinical decision making in this population, this study examined the association between prior abdominal procedures and outcomes in patients undergoing PD catheter insertion.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Adults undergoing their first PD catheter insertion between November 1, 2011 and November 1, 2020, at 11 institutions in Canada and the US participating in the International Society for Peritoneal Dialysis (ISPD) North American Catheter Registry.

EXPOSURE

Prior abdominal procedure(s), defined as any procedure that enters the peritoneal cavity.

OUTCOMES

Primary outcome: time to the first of abandonment of the PD catheter, or interruption/termination of PD.

SECONDARY OUTCOMES

rates of emergency room visits, hospitalizations, and procedures.

ANALYTICAL APPROACH

Cumulative incidence curves were used to describe the risk over time and an adjusted Cox proportional hazards model was used to estimate the association between the exposure and primary outcome. Models for count data were used to estimate the associations between the exposure and secondary outcomes.

RESULTS

A total of 855 patients met the inclusion criteria. Thirty-one percent had a history of a prior abdominal procedure and 20% experienced at least one PD catheter-related complication that led to the primary outcome. Prior abdominal procedures were not associated with an increased risk of the primary outcome [Adjusted HR 1.12 (95% CI 0.68-1.84)]. Upper abdominal procedures were associated with a higher adjusted hazard of the primary outcome, but there was no dose-response relationship concerning the number of procedures. There was no association between prior abdominal procedures and other secondary outcomes.

LIMITATIONS

Observational study and cohort limited to sample of patients felt to be potential candidates for PD catheter insertion.

CONCLUSION

A history of prior abdominal procedure(s) does not appear to influence catheter outcomes following PD catheter insertion. Such a history should not be a contraindication to peritoneal dialysis.

The impact of the Starting dialysis on Time, At home on the Right Therapy (START) project on the use of peritoneal dialysis

BACKGROUND

Peritoneal dialysis (PD) is actively promoted, but increasing PD utilisation is difficult. The objective of this study was to determine if the Starting dialysis on Time, At Home, on the Right Therapy (START) project was associated with an increase in the proportion of dialysis patients receiving PD within 6 months of starting therapy.

METHODS

Consecutive patients over age 18, with end-stage kidney failure, who started dialysis between 1 April 2015 and 31 March 2018 in the province of Alberta, Canada. Programmes were provided with high-quality data about the individual steps in the process of care that drive PD utilisation that were used to identify problem areas, design and implement interventions to address them, and then evaluate whether those interventions had impact. The primary outcome was the proportion of patients receiving PD within 6 months of starting dialysis. Secondary outcomes included hospitalisation, death or probability of transfer to haemodialysis (HD). Interrupted time series methodology was used to evaluate the impact of the quality improvement initiative on the primary and secondary outcomes.

RESULTS

A total of 1962 patients started dialysis during the study period. Twenty-seven per cent of incident patients received PD at baseline, and there was a 5.4% (95% confidence interval: 1.5-9.2) increase in the use of PD in the province immediately after implementation. There were no changes in the rates of hospitalisation, death or probability of transfer to HD after the introduction of START.

CONCLUSIONS

The approach used in the START project was associated with an increase in the use of PD in a setting with high baseline utilisation.

Proton Pump Inhibitors Use in Kidney Transplant Recipients: A Population-Based Study

Background

Kidney transplant recipients are commonly prescribed proton-pump inhibitors (PPIs), but due to concern for polypharmacy, chronic use should be limited.

Objective

The objective was to describe PPI use in kidney transplant recipients beyond their first year of transplant to better inform and support deprescribing initiatives.

Design

We conducted a retrospective, population-based cohort study using linked health care databases.

Setting

This study was conducted in Alberta, Canada.

Patients

We included all prevalent adult, kidney-only transplant recipients between April 2008 and December 2017 who received their transplant between May 2002 and December 2017.

Measurements

The primary outcome was ongoing or new PPI use and patterns of use, including frequency and duration of therapy, and assessment of indication for PPI use.

Methods

We ascertained baseline characteristics, covariate information, and outcome data from the Alberta Kidney Disease Network (AKDN). We compared recipients with evidence of a PPI prescription in the 3 months prior to study entry to those with a histamine-2-receptor antagonist (H2Ra) fill and those with neither.

Results

We identified 1823 kidney transplant recipients, of whom 868 (48%) were on a PPI, 215 (12%) were on an H2Ra, and 740 (41%) were on neither at baseline. Over a median follow-up of 5.4 years (interquartile range [IQR] = 2.6-9.3), there were almost 45 000 unique PPI prescriptions dispensed, the majority (80%) of which were filled by initial PPI users. Recipients who were on a PPI at baseline would spend 91% (IQR = 70-98) of their graft survival time on a PPI in follow-up, and nephrologists were the main prescribers. We identified an indication for ongoing PPI use in 54% of recipients with the most common indication being concurrent antiplatelet use (26%).

Limitations

Our kidney transplant recipients have access to universal health care coverage which may limit generalizability. We identified common gastrointestinal indications for PPI use but did not include rare conditions due to concerns about the validity of diagnostic codes. In addition, symptoms suggestive of reflux may not be well coded as the focus of follow-up visits is more likely to focus on kidney transplant.

Conclusions

Many kidney transplant recipients are prescribed a PPI at, or beyond, the 1-year post-transplant date and are likely to stay on a PPI in follow-up. Almost half of the recipients in our study did not have an identifiable indication for ongoing PPI use. Nephrologists frequently prescribe PPIs to kidney transplant recipients and should be involved in deprescribing initiatives to reduce polypharmacy.

Risk Factors for Developing Low Estimated Glomerular Filtration Rate and Albuminuria in Living Kidney Donors

Rationale & Objective

Chronic kidney disease is associated with significant morbidity and mortality in the general population, but little is known about the incidence and risk factors associated with developing low estimated glomerular filtration rate (eGFR) and moderate-severe albuminuria in living kidney donors following nephrectomy.

Study Design

Retrospective, population-based cohort study.

Setting & Participants

Kidney donors in Alberta, Canada.

Exposure

Donor nephrectomy between May 2001 and December 2017.

Outcome

Two eGFR measurements <45 mL/min/1.73 m2 or 2 measurements of moderate or severe albuminuria from 1-year postdonation onwards that were at least 90 days apart.

Analytical Approach

Associations between potential risk factors and the primary outcome were assessed using Cox proportional hazard regression analyses.

Results

Over a median follow-up period of 8.6 years (IQR, 4.7-12.6 years), 47 of 590 donors (8.0%) developed sustained low eGFR or moderate-severe albuminuria with an incidence rate of 9.2 per 1,000 person-years (95% confidence interval, 6.6-11.8). The median time for development of this outcome beyond the first year after nephrectomy was 2.9 years (IQR, 1.4-8.0 years). Within the first 4 years of follow-up, a 5 mL/min/1.73 m2 lower predonation eGFR increased the hazard of developing postdonation low eGFR or moderate-severe albuminuria by 26% (adjusted HR, 1.26; 95% CI, 1.10-1.44). Furthermore, donors were at higher risk of developing low eGFR or albuminuria if they had evidence of predonation hypertension (adjusted HR, 2.52; 95% CI, 1.28-4.96) or postdonation diabetes (adjusted HR, 4.72; 95% CI, 1.54-14.50).

Limitations

We lacked data on certain donor characteristics that may affect long-term kidney function, such as race, smoking history, and transplant-related characteristics.

Conclusions

A proportion of kidney donors at an incidence rate of 9.2 per 1,000 person-years will develop low eGFR or albuminuria after donation. Donors with lower predonation eGFR, predonation hypertension, and postdonation diabetes are at increased risk of developing this outcome.

Follow-up Care of Critically Ill Patients With Acute Kidney Injury: A Cohort Study

Rationale & Objective

To evaluate follow-up care of critically ill patients with acute kidney injury (AKI).

Study Design

Retrospective cohort study.

Setting & Participants

Patients admitted to the intensive care unit (ICU) with AKI in Alberta, Canada from 2005 to 2018, who survived to discharge without kidney replacement therapy or estimated glomerular filtration rate <15 mL/min/1.73 m2.

Exposure

AKI (defined as ≥50% or ≥0.3 mg/dL serum creatinine increase).

Outcomes

The primary outcome was the cumulative incidence of an outpatient serum creatinine and urine protein measurement at 3 months postdischarge. Secondary outcomes included an outpatient serum creatinine or urine protein measurement or a nephrologist visit at 3 months postdischarge.

Analytical Approach

Patients were followed from hospital discharge until the first of each outcome of interest, death, emigration from the province, kidney replacement therapy (maintenance dialysis or kidney transplantation), or end of study period (March 2019). We used non-parametric methods (Aalen-Johansen) to estimate the cumulative incidence functions of outcomes accounting for competing events (death and kidney replacement therapy).

Results

There were 29,732 critically ill adult patients with AKI. The median age was 68 years (IQR, 57-77), 39% were female, and the median baseline estimated glomerular filtration rate was 72 mL/min/1.73 m2 (IQR, 53-90). The cumulative incidence of having an outpatient creatinine and urine protein measurement at 3 months postdischarge was 25% (95% CI, 25-26). At 3 months postdischarge, 64% (95% CI, 64-65) had an outpatient creatinine measurement, 28% (95% CI, 27-28) had a urine protein measurement, and 5% (95% CI, 4-5) had a nephrologist visit.

Limitations

We lacked granular data, such as urine output.

Conclusions

Many critically ill patients with AKI do not receive the recommended follow-up care. Our findings highlight a gap in the transition of care for survivors of critical illness and AKI.

Delayed tension pneumocephalus and pneumorrhacis after routine cervical spine surgery treated successfully without burr holes

Tension pneumocephalus (TP) after spinal surgery is very rare with only a few cases reported in the English literature. Most cases of TP occur rapidly after spinal surgery. Traditionally, TP is managed using burr holes to relieve intracranial pressure. However, our case highlights a rare delayed presentation of TP and pneumorrhacis 1 month after routine cervical spine surgery. It is to our knowledge the first case of TP after spinal surgery to be treated using dural repair and supportive care. A 75-year-old woman presented with TP after having routine cervical decompression and stabilisation for cervical myelopathy. She re-presented 1 month after her initial operation with a leaking wound and altered mental status, which deteriorated rapidly shortly after admission. This, in combination with her radiographic features, influenced the decision to explore her surgical wound emergently. She made a full recovery and was discharged after 2 weeks in hospital. We hope to emphasise the need for a high index of suspicion for cerebrospinal fluid leaks and the low threshold to return to theatre to repair a potential dural defect, as well as illustrate that TP after spinal surgery can be treated successfully without burr holes.

Progression of Kidney Disease in Kidney Transplant Recipients With a Failing Graft: A Matched Cohort Study

Background

Few studies have assessed outcomes in transplant recipients with failing grafts as most studies have focused on outcomes after graft loss.

Objective

To determine whether renal function declines faster in kidney transplant recipients with a failing graft than in people with chronic kidney disease of their native kidneys.

Design

Retrospective cohort study.

Setting

Alberta, Canada (2002-2019).

Patients

We identified kidney transplant recipients with a failing graft (2 estimated glomerular filtration rate [eGFR] measurements 15-30 mL/min/1.73 m2 ≥90 days apart).

Measurements

We compared the change in eGFR over time (eGFR with 95% confidence limits, LCLeGFRUCL) and the competing risks of kidney failure and death (cause-specific hazard ratios [HRs], LCLHRUCL).

Methods

Recipients (n = 575) were compared with propensity-score-matched, nontransplant controls (n = 575) with a similar degree of kidney dysfunction.

Results

The median potential follow-up time was 7.8 years (interquartile range, 3.6-12.1). The hazards for kidney failure (HR1.101.331.60) and death (HR1.211.592.07) were significantly higher for recipients, while the eGFR decline over time was similar (recipients vs controls: -2.60-2.27-1.94 vs -2.52-2.21-1.90 mL/min/1.73 m2 per year). The rate of eGFR decline was associated with kidney failure but not death.

Limitations

This was a retrospective, observational study, and there is a risk of bias due to residual confounding.

Conclusions

Although eGFR declines at a similar rate in transplant recipients as in nontransplant controls, recipients have a higher risk of kidney failure and death. Studies are needed to identify preventive measures to improve outcomes in transplant recipients with a failing graft.

The relationship between parental adverse childhood experiences and the health, well-being and development outcomes of their children: a systematic review

OBJECTIVES

A growing body of research is emerging regarding the relationship between parental adverse childhood experiences (ACEs) and negative health, well-being and developmental outcomes in their children. This systematic review seeks to understand the relationship between parental ACEs and the health, well-being and developmental outcomes of their children and whether the relationships differ according to the number and type of parental ACEs.

STUDY DESIGN

Systematic review.

METHOD

The review includes articles published between 2000 and 2021 from studies using quantitative longitudinal methods and multivariate analysis to investigate the relationship between parental ACEs and their offspring's outcomes. Relevant studies were identified through a systematic search of five databases and findings synthesised using a narrative synthesis. This review was registered on PROSPERO (CRD42021274068).

RESULTS

Nineteen studies met the inclusion criteria and were included in the review. This resulted in a combined population sample of 124,043 parents and 128,400 children. Diversity in measurement of parental ACE exposure and in the type of ACEs measured within the studies precluded a meta-analysis. Offspring of parents exposed to ACEs had a higher risk of a range of negative health, well-being and developmental outcomes. This relationship differs according to the number and type of parental ACEs, with a positive relationship observed between the number of parental ACEs and the risk of negative health, well-being and development outcomes in their children.

CONCLUSIONS

These findings indicate that screening for parental ACEs by health visitors, midwives and other health or social care staff may identify an at-risk population of infants, children and adolescents and improve child outcomes.

Fallibility of tattooing colonic neoplasia ahead of laparoscopic resection: a retrospective cohort study

INTRODUCTION

Precise geographical localisation of colonic neoplasia is a prerequisite for proper laparoscopic oncological resection. Preoperative endoscopic peri-tumoural tattoo practice is routinely recommended but seldom scrutinised.

METHODS

A retrospective review of recent consecutive patients with preoperative endoscopic lesional tattoo who underwent laparoscopic colonic resection as identified from our prospectively maintained cancer database with supplementary clinical chart and radiological, histological, endoscopic and theatre database/logbook interrogation.

RESULTS

Some 210 patients with 'tattooed' colonic neoplasia were identified, of whom 169 underwent laparoscopic surgery (mean age 68 years, median BMI 27.8kg/m2, male-to-female ratio 95:74). The majority of tumours were malignant (149; 88%), symptomatic (133; 79%) and proximal to the splenic flexure (92; 54%). Inaccurate colonoscopist localisation judgement occurred in 12% of cases, 60% of which were corrected by preoperative staging computed tomography scan. A useful lesional tattoo was absent in 11/169 cases (6.5%) being specifically stated as present in 104 operation notes (61%) and absent in 10 (5.9%). Tumours missing overt peritumoral tattoos intraoperatively were more likely to be smaller, earlier stage and injected longer preoperatively (p=0.006), although half had histological ink staining. Eight lesions missing tattoos were radiologically occult. Four (44%) of these patients had on-table colonoscopy, and five (55%) needed laparotomy (conversion rate 55% vs 23% overall, p<0.005) with one needing a second operation to resect the initially missed target lesion. Mean (range) operative duration and postoperative length of stay of those missing tattoos compared with those with tattoos was 200 (78-300) versus 188 (50-597) min and 15.5 (4-22) versus 12(4-70) days (p>0.05).

CONCLUSIONS

Tattoo in advance of attempting laparoscopic resection is vital for precision cancer surgery especially for radiologically unseen tumours to avoid adverse clinical consequence.

Left distal ureter leiomyosarcoma: a case report

Primary leiomyosarcoma of the ureter is an extremely rare, aggressive malignancy of the urinary tract. This report describes a case of primary leiomyosarcoma of the distal left ureter in a middle-aged male, with no tumor recurrence achieved following resection and end-to-end ureteroureterostomy.

Isolated IgG2 deficiency is an independent risk factor for exacerbations in bronchiectasis

BACKGROUND

Immunoglobulin G (IgG) subclass 2 deficiency is the most frequent IgG subclass deficiency identified in patients with bronchiectasis, but its clinical significance is not known.

AIM

To analyse if bronchiectasis patients with isolated IgG2 deficiency at risk of recurrent exacerbations and/or hospitalization? Do patients with IgG2 deficiency have worse disease progression?

DESIGN AND METHODS

This is a retrospective study (2015-20) exploring independent risk factors for recurrent exacerbations (3 or more per year) and/or hospitalization with bronchiectasis exacerbations using multivariable models using binary logistic regression. There was no patient with IgG deficiency, IgG 1, 3 or 4 deficiency, or IgA or IgM deficiency included. In this model, the authors included: serum IgG2 level; lung function; body mass index; MRC breathlessness scale; age; sex; number of bronchiectatic lobes; bacterial colonization; comorbidities; and the use of long-term immunosuppressant drugs or antibiotics for more than 28 days. Analysing 2-year longitudinal data, one-way ANOVA and Mann-Whitney U-test were used to compare bronchiectasis severity between patients with different IgG2 levels.

RESULTS

Serum IgG2 levels (<2.68 g/l, 2.68-3.53 g/l and 3.54-4.45 g/l); hospital admission in the preceding 2 years; bacterial colonization with potentially pathogenic organisms and asthma were independent predictors for three or more bronchiectasis exacerbations. Those with low IgG2 levels (<2.68 g/l and 2.68-3.53 g/l), had worsening progression of their bronchiectasis, using the Bronchiectasis Severity Index, over 1 year compared with those who were IgG2 replete (>4.45 g/l) (P = 0.003, 0.013).

CONCLUSION

Reduced IgG2 levels were an independent predictor for bronchiectasis exacerbations and have increased disease progression.

Development and external validation of a machine learning model for progression of Chronic Kidney Disease

Introduction

Methods

Results

Conclusion

The availability of support and peritoneal dialysis survival: A cohort study

BACKGROUND

Providing support is important to maintain a patient on peritoneal dialysis (PD), though its impact on outcomes has not been investigated thoroughly. We examined the association between having support and risk of a transfer to hemodialysis.

METHODS

In this retrospective observational cohort study, we used data captured in the Dialysis Measurement Analysis and Reporting system about patients who started PD in Alberta, Canada, between 1 January 2013 and 30 September 2018. Support was defined as the availability of a support person in the home who was able, willing and available to provide support for PD in the patient's residence. The outcome of interest was a transfer to hemodialysis for at least 90 days. We estimated the cumulative incidence of a transfer over time accounting for competing risks and hazard ratios to summarise the association between support and a transfer. We split follow-up time as hazard ratios varied over time.

RESULTS

Six hundred and eighty-three incident PD patients, median age 58 years (IQR: 47-68) and 35% female, were followed for a median of 15 months. The cumulative incidence of a transfer to hemodialysis at 24 months was 26%. Having support was associated with a reduced risk of a transfer between 3 and 12 months after the start of dialysis (HR_3-12mo: 0.44; 95% CI: 0.25-0.78), but not earlier (hazard ratio (HR)_<3mo: 0.96; 95% confidence interval (CI): 0.55-1.69) or later (HR_>12mo: 1.19; 95% CI: 0.65-2.17).

CONCLUSIONS

A transfer to hemodialysis is common. Having a support person at home is associated with a short-term protective effect after the initiation of PD.

A191 PERSISTENT BENEFIT OF DIETITIAN-LED GLUTEN-FREE DIET EDUCATION AT CD DIAGNOSIS ON DIETARY ADHERENCE IN CHILDREN AND ADULTS WITH TYPE 1 DIABETES AND CELIAC DISEASE

Background

Celiac disease (CD) is a common autoimmune comorbidity of type 1 diabetes (T1D) with a gluten-free diet (GFD) being the current gold standard treatment for this condition. Adherence to a GFD can be impacted by several factors including dietetic counselling, yet little is known about the impact of clinic-based interventions on long-term GFD adherence in this population.

Aims

To prospectively evaluate the impact of a dietitian-led GFD education intervention on adherence to a GFD in children and adults with T1D and CD over a 3-year period.

Methods

A cohort of N=62 pediatric and adult subjects who screened seropositive for CD as part of the CD-DIET clinical trial were followed over a 3-year period post-CD diagnosis and assessed on the basis of the GFD education regimen they received at initial CD diagnosis. This included 3 groups: 1) intensive dietitian training (IDT = 5 dietitian visits over 1 year while following GFD), 2) single dietitian training (SDT = 1 GFD training session after 1 year of following GCD) and 3) no dietitian training (NDT) at CD diagnosis. Annual visits included serologic testing of TTG-IgA titres, anthropometric assessments and the completion of questionnaires evaluating diet and adherence to a GFD. Data was analysed longitudinally using linear mixed effects and generalized estimating equations (GEE) regression modeling adjusting for the fixed effects of age, sex, duration of diabetes and time.

Results

At baseline, participants who received IDT (n=15), SDT (n=16) and NDT (n=31) represented 24.2%, 25.8%, and 50.0% of the cohort, respectively. Over the 3-year study period, participants in the IDT group had the greatest odds of self-reporting being a GFD, with odds 4.3 (95%CI: 1.1 to 16.4; P=0.033) and 9.5 (95%CI: 2.7 to 33.7; P&lt;0.001) greater than the SDT and NDT groups, respectively. The assessment of daily gluten intakes less than 10mg, as recommended for a GFD, revealed a lack of differences between the IDT and SDT groups. In contrast, the NDT group had significantly lower odds of meeting this threshold relative to those who received IDT (OR=0.2; 95%CI: 0.04 to 0.56; P=0.004). No longitudinal differences in TTG-IgA levels were seen between groups over the 3-year period.

Conclusions

In diabetes patients greater contact with a dietitian at CD diagnosis was associated with higher levels of GFD adherence over time, which was not reflected in follow-up Serologic evaluation. These findings highlight the importance of nutritional support in patients with both diabetes and celiac disease at the time of CD diagnosis. In addition, following TTG-IgA alone does not fully inform dietary compliance to a GFD.

Diet teaching stratification

Funding Agencies

Juvenile Diabetes Research Foundation / PSI

A multi-centred sequential trial comparing PEGASUS, an intervention to promote shared decision making about breast reconstruction with usual care

Decision making about breast reconstruction (BR) is complex. The Patients' Expectations and Goals: Assisting Shared Understanding of Surgery (PEGASUS) intervention aims to support shared decision making by helping women and clinicians clarify and discuss their expectations around reconstructive surgery. We conducted a multi-centred sequential trial comparing PEGASUS (n = 52) with usual care (UC) (n = 86) in women considering reconstruction, who completed outcome measures at baseline, and 3, 6 and 12 months post-surgery. The primary outcome was BR-specific quality of life (Breast-Q) 6 months post-intervention. Secondary outcomes were health-related quality of life (EQ-5D-5L), capabilities (ICECAP-A) and decisional regret, compared using t-tests and Cohen's d. Comparative analyses revealed no significant differences between groups in Breast-Q scores at any time point, except for a favourable effect for UC on psychological well-being at 3 months (t = -2.41, p = .019, d= -0.59). Intervention participants reported significantly higher, therefore improved, ICECAP-A (t = -2.13, p = .037, d = -0.45) and EQ VAS (t = -2.28, p = .026, d = -0.49) scores at 12 months compared to UC. Decisional regret was significantly lower in the PEGASUS group compared to the UC group at 6 months (t =2.06, p = .044, d= -0.51), but this was not sustained at 12 months. In conclusion, the PEGASUS intervention offers some benefits to women considering BR. At times, women experienced less decisional regret, improved health-related quality of life and capability well-being. Findings are discussed in the light of fidelity testing and embedding PEGASUS into practice.

505 Failed Femoral Nail with Significant Operative Technical Difficulty: A Practical Solution to Achieve Metalwork Extraction Using Conical Screw Remover

Introduction

There is a greater risk of delayed healing and revision surgery in atypical femoral fractures (AFFs). Although non-union in reamed intra-medullary (IM) nailing is relatively uncommon, it can lead to fracture of the nail and present a considerable challenge to the treating surgeon.

Case Report

We present a case of AFF treated with IM nail fixation. Metalwork failure of the nail prompted removal of distal locking screws and plating of the fracture site at 8 months. Failure of the plate-bone interface 3 months later led to further revision surgery to remove the broken metalwork. We focus on the significant operative difficulty encountered during removal of the failed IM metalwork and provide a novel practical solution to overcome this particular challenge - insertion of a conical cannulated screw remover under fluoroscopy guidance to create an interference fit with the distal segment of the broken nail.

Discussion

This case is an example of significant and unexpected intra-operative technical difficulty, requiring improvisation and teamwork to manage. We introduce an accessible and uncomplicated alternative to the existing techniques for removal of a broken femoral nail and in doing so hope to benefit peers and colleagues should they encounter similar difficulties in the future.

Association Between Attempted Arteriovenous Fistula Creation and Mortality in People Starting Hemodialysis via a Catheter: A Multicenter, Retrospective Cohort Study

Background:

In North America, most people start hemodialysis via a central venous catheter (“catheter”). These patients are counseled to undergo arteriovenous fistula (“fistula”) creation within weeks of starting hemodialysis because fistulas are associated with improved survival.

Objectives:

To determine whether attempting to create a fistula in patients who start hemodialysis via a catheter is associated with improved mortality. We also sought to determine whether differences in baseline patient characteristics, vascular procedures for access-related complications, or days in hospital may confound or mediate the relationship between attempted fistula creation and mortality.

Design:

Multicenter, retrospective cohort study.

Setting:

Six dialysis programs located in Ontario, Alberta, and Manitoba.

Patients:

Patients aged ≥18 years who initiated hemodialysis via a catheter between January 1, 2004, and May 31, 2012, who had not had a previous attempt at fistula creation. We excluded those who had a life expectancy less than 1 year, who transitioned to peritoneal dialysis within 6 months of starting dialysis, and people who started hemodialysis via a graft.

Measurements:

Attempted fistula creation, all-cause mortality, patient characteristics and comorbidities, vascular procedures for access-related complications, and days spent in hospital.

Methods:

We used survival methods, including marginal structural models, to account for immortal time bias and time-varying confounding.

Results:

In total, 1832 patients initiated hemodialysis via a catheter during the study period and met inclusion criteria. Of these patients, 565 (31%) underwent an attempt at fistula creation following hemodialysis start. As compared to those who did not receive a fistula attempt, these people were younger, had fewer comorbidities, and were more likely to have started dialysis as an outpatient and to have received pre-dialysis care. In a marginal structural model controlling for baseline characteristics and comorbidities, attempted fistula creation was associated with a significantly lower mortality (hazard ratio [HR] = 0.53; 95% confidence interval [CI] = 0.43-0.66). This effect did not appear to be confounded or mediated by differences in the number of days spent in hospital or vascular procedures for access-related complications. It also remained similar in analyses restricted to patients who survived at least 6 months (HR = 0.60; 95% CI = 0.47-0.77) and to patients who started hemodialysis as an outpatient (HR = 0.48; 95% CI = 0.33-0.68).

Limitations:

There is likely residual confounding and treatment selection bias.

Conclusions:

In this multicenter cohort study, attempting fistula creation in people who started hemodialysis via a catheter was associated with significantly reduced mortality. This reduction in mortality could not be explained by differences in patient characteristics or comorbidities, days spent in hospital, or vascular procedures for access-related complications. Residual confounding or selection bias may explain the observed benefits of fistulas for hemodialysis access.

Trial Registration:

Not applicable (cohort study).

PEGASUS: the Design of an Intervention to Facilitate Shared Decision-making in Breast Reconstruction

Studies have found varying levels of satisfaction after breast reconstruction surgery with a substantial group of patients reporting some level of regret about their decision. The variable outcomes reported by women undergoing breast reconstruction surgery suggest a role for improved pre-operative communication and shared decision-making (SDM) between patient and health professional. Pragmatic approaches such as decision aids have been evaluated, but the aim of the Patient Expectations and Goals Assisting Shared Understanding of Surgery (PEGASUS) intervention is to facilitate closer interaction between the patient and clinical team. PEGASUS is a standardised two-stage process, in which patients' goals are first elicited, ranked in importance and recorded before being used to frame discussion and decision-making with the surgeon managing care. Following the Medical Research Council (MRC) model, feasibility and acceptability studies have already been reported and a 4-year multicentre randomised controlled trial of 180 participants is underway, (completion 2020). This paper therefore focuses on the design of the intervention itself, in line with recent advice that interventions, in comparison with evaluations, commonly lack a theoretical base and are often under reported. We report a retrospective application of the Capability, Opportunity, Motivation-Behaviour (COM-B) model to provide explicit detail of each step in the intervention design. This is intended to facilitate replication by other clinicians and to provide systematic guidance for others wishing to develop PEGASUS as a strategy for implementing SDM in other clinical populations. Trial Registration: ISRCTN 18000391 (DOI 10.1186/ISRCTN18000391) 27/01/2016.

Tolerability of four-drug antiretroviral combination therapy in primary HIV-1 infection

Objectives

Rapid initiation of antiretroviral therapy (ART) is important for individuals with high baseline viral loads, such as in primary HIV‐1 infection (PHI). Four‐drug regimens are sometimes considered; however, data are lacking on tolerability. We aimed to evaluate the tolerability of four‐drug regimens used in the Research in Viral Eradication of HIV‐1 Reservoirs (RIVER) study.

Methods

At enrolment, ART‐naïve adult participants or those newly commenced on ART were initiated or intensified to four‐drug regimens within 4 weeks of PHI. Rapid start was defined as pre‐confirmation or ≤ 7 days of confirmed diagnosis. Primary and secondary outcomes were patient‐reported adherence measured by 7‐day recall and regimen switches between enrolment and randomization, respectively.

Results

Overall, 54 men were included: 72.2% were of white ethnicity, with a median age of 32 years old, 42.6% had a viral load of ≥ 100 000 HIV‐1 RNA copies/mL, and in 92.6% sex with men was the mode of acquisition of HIV‐1. Twenty (37%) started a four‐drug regimen and 34 (63%) were intensified. Rapid ART initiation occurred in 28%, 100% started in ≤ 4 weeks. By weeks 4, 12, and 24, 37.0%, 69.0%, and 94.0% were undetectable (viral load < 50 copies/mL), respectively. Adherence rates of 100% at weeks 4, 12, 22 and 24 were reported in 88.9%, 87.0%, 82.4% and 94.1% of participants, respectively. Five individuals switched to three drugs, four changed their regimen constituents, and two switched post‐randomization.

Conclusions

Overall, four‐drug regimens were well tolerated and had high levels of adherence. Whilst their benefit over three‐drug regimens is lacking, our findings should provide reassurance if a temporarily intensified regimen is clinically indicated to help facilitate treatment.

Starting Dialysis on Time, At Home on the Right Therapy (START): Description of an Intervention to Increase the Safe and Effective Use of Peritoneal Dialysis

Background:

Most of the patients with end-stage kidney failure are treated with dialysis. Jurisdictions around the world are actively promoting peritoneal dialysis (PD) because it is equivalent to hemodialysis in terms of clinical outcomes, but is less costly. Unfortunately, PD penetration remains low.

Objectives:

The Starting dialysis on Time, At Home, on the Right Therapy (START) Project had 2 overarching goals: (1) to provide information that would help programs increase the safe and effective use of PD, and (2) to reduce inappropriate, early initiation of dialysis in patients with kidney failure. In this article, we focus on the first objective and describe the rationale for START and the methods employed.

Design:

The START Project was a comprehensive, province-wide quality improvement intervention.

Setting:

The START project was implemented in both Alberta Kidney Care (AKC)-South and AKC-North, including all 7 renal programs in the province.

Patients:

The project included all patients who commenced maintenance dialysis between October 1, 2015, and March 31, 2018, in Alberta, Canada who met our inclusion criteria.

Measurements:

We reported baseline characteristics of incident dialysis patients overall, and by site. Our key performance indicator was the proportion of patients who received PD for any period of time within 180 days of the first dialysis treatment. Reports also included detailed metrics pertaining to the 6 steps in the process of modality selection and we had the capacity to provide more granular data on an as-needed basis. To understand loss of PD patients, we reported the numbers of incident patients who recovered kidney function, experienced technique failure, received a transplant, were lost to follow-up, transferred to another program, or died.

Methods:

START provided dialysis programs with a conceptual framework for understanding the drivers of PD utilization. High-quality, detailed data were collected using a tool that was custom-built for this purpose, and were mapped to steps in the process of care that drove the outcomes of interest. This allowed sites to identify gaps in care, develop action plans, and implement local interventions to address them. The process was supported by an Innovation Learning Collaborative consisting of 3 learning sessions that brought frontline staff together from across the province to share strategies and learnings. Ongoing data collection allowed teams to determine whether their interventions were effective at each subsequent learning session, and to revisit their interventions if required (the “Plan-Do-Study-Act Cycle”).

Results:

Future work will report on the impact of the START project on incident PD utilization at a provincial and regional level.

Limitations:

The time required to design and implement interventions in practice, as well as the need for multiple PDSA (Plan-Do-Study-Act) cycles to see results, meant that the true potential may not be realized during a relatively short intervention period. Change required buy-in and support from local and provincial leadership and frontline staff. In the absence of accountability for local performance, we relied on the goodwill of participating programs to use the information and resources provided to effect change. Finally, the burden of documentation and data collection for frontline staff was high at baseline. We anticipated that adding supplemental data collection would be difficult.

Conclusions:

The START project was a comprehensive, province-wide initiative to maximize the safe and effective use of PD in Alberta, Canada. It standardized the management of incident dialysis patients, leveraged high-quality data to facilitate the reporting of metrics mapped to steps in the process of care that drove incident PD utilization, and helped programs to identify gaps in care and target them for improvement. Future work will report on the impact of the program on incident utilization at the provincial and regional level.

Effect of diagnostic score reporting following a structured clinical assessment of dental hygiene student performance

Background

Diagnostic score reporting is one method of providing feedback to all students following a structured clinical assessment but its effect on learning has not been studied. The objective of this study was to assess the impact of this feedback on student reflection and performance following a dental hygiene assessment.

Methods

In 2016, dental hygiene students at the University of Alberta participated in a mock structured clinical assessment during which they were randomly assigned to receive a diagnostic score report (intervention group) or an overall percentage grade of performance (control group). The students later reflected upon their performance and took their regularly scheduled structured clinical assessment. Reflections underwent content analysis by diagnostic domains (eliciting essential information, effective communication, client-centred care, and interpreting findings). Results were analysed for group differences.

Results

Students performed best on eliciting essential information (92%) and poorest on interpreting findings (42%). The intervention group was more likely to view interpreting findings as a weakness, p = 0.007, while the control group was more likely to view eliciting essential information as a weakness, p = 0.04. No differences were found on the actual assessment scores, p > 0.05.

Discussion

Students who received diagnostic score reporting appeared to reflect more accurately upon their weaknesses. However, this knowledge did not translate into improved performance. Modifications and enhancements to the report may be necessary before an effect on performance will be seen.

Conclusion

Diagnostic score reporting is a promising feedback method that may aid student reflection. More research is needed to determine if these reports can improve performance.

Development of diagnostic score reporting for a dental hygiene structured clinical assessment

Background

Structured clinical assessments capture key information about performance that is rarely shared with the student as feedback. The purpose of this review is to describe a general framework for applying diagnostic score reporting within the context of a structured clinical assessment and to demonstrate that framework within dental hygiene.

Methods

The framework was developed using current research in the areas of structured clinical assessments, test development, feedback in higher education, and diagnostic score reporting. An assessment blueprint establishes valid diagnostic domains by linking clinical competencies and test items to the domains (e.g., knowledge or skills) the assessment intends to measure. Domain scores can be given to students as reports that identify strengths and weaknesses and provide information on how to improve.

Results

The framework for diagnostic score reporting was applied to a dental hygiene structured clinical assessment at the University of Alberta in 2016. Canadian dental hygiene entry-to-practice competencies guided the assessment blueprinting process, and a modified Delphi technique was used to validate the blueprint. The final report identified 4 competency-based skills relevant to the examination: effective communication, client-centred care, eliciting essential information, and interpreting findings. Students received reports on their performance within each domain.

Discussion

Diagnostic score reporting has the potential to solve many of the issues faced by administrators, such as item confidentiality and the time-consuming nature of providing individual feedback.

Conclusion

Diagnostic score reporting offers a promising framework for providing valid and timely feedback to all students following a structured clinical assessment.

The nature and importance of women's goals for immediate and delayed breast reconstruction

OBJECTIVES

Increasingly, women undergo breast reconstruction (BR) surgery to restore health-related and psychosocial quality of life after mastectomy. Most research focuses on BR outcomes rather than women's pre-surgical expectations of, and goals for, immediate (IBR) or delayed (DBR) procedures, yet such information could support women's decision-making. This study aimed to investigate women's BR goals, whether they differed according surgery timing (IBR or DBR), and the importance women placed on them.

METHODS

Seventy-six women considering DBR (n = 50) or IBR (n = 26) at a UK hospital were encouraged to clarify their BR goals and rate the importance of achieving each one. Content analysis categorised and counted the frequency of the goals they reported.

RESULTS

Fifteen goal categories (7 surgical, e.g. scarring; 8 psychosocial/lifestyle, e.g. feeling feminine) were identified. Many (e.g. scarring, intimacy) were reported by a similar percentage of women in each surgical group, however, differences were identified (e.g. breast sensation was not mentioned by women considering IBR). Women reported more psychosocial (n = 206) than surgical goals (n = 160). Further, an independent t-tests revealed that women in both groups placed significantly more importance on the psychosocial (M = 9.4) than surgical goals (M = 8.5).

CONCLUSIONS

This study highlights the variety of goals women have for BR, the importance they attach to them, and differences and similarities between those seeking IBR and DBR. Future research should consider whether BR goals are met, how goal achievement influences satisfaction with outcome over time and how best to incorporate goals into pre-surgical treatment decision-making.

Four steps to standardize reporting of peritoneal dialysis technique failure: A proposed approach

BACKGROUND

Technique failure is an important outcome measure in research and quality improvement in peritoneal dialysis (PD) programs, but there is a lack of consistency in how it is reported.

METHODS

We used data collected about incident dialysis patients from 10 Canadian dialysis programs between 1 January 2004 and 31 December 2018. We identified four main steps that are required when calculating the risk of technique failure. We changed one variable at a time, and then all steps, simultaneously, to determine the impact on the observed risk of technique failure at 24 months.

RESULTS

A total of 1448 patients received PD. Selecting different cohorts of PD patients changed the observed risk of technique failure at 24 months by 2%. More than one-third of patients who switched to hemodialysis returned to PD-90% returned within 180 days. The use of different time windows of observation for a return to PD resulted in risks of technique failure that differed by 16%. The way in which exit events were handled during the time window impacted the risk of technique failure by 4% and choice of statistical method changed results by 4%. Overall, the observed risk of technique failure at 24 months differed by 20%, simply by applying different approaches to the same data set.

CONCLUSIONS

The approach to reporting technique failure has an important impact on the observed results. We present a robust and transparent methodology to track technique failure over time and to compare performance between programs.

Life of a droplet: Buoyant vortex dynamics drives the fate of micro-particle expiratory ejecta

We show that the dynamics of the expiratory cloud ejected during human respiratory events can be modeled by extending the theory of buoyant vortex rings with an initial momentum. We embed the integral conservation laws that govern the cloud's motion into the model of an expanding vortex to determine the velocity field inside and outside the cloud. We then apply a Lagrangian particle-tracking model to calculate the trajectories of the mucosalivary droplets suspended within the cloud. Our results show very good agreement with the available experimental data. The vortex is shown to have a significant effect on suspending the droplets present in the cloud, increasing the time they remain airborne and extending their range further than predicted by the existing models. We also study the role that initial conditions have on the maximum streamwise range of the droplets, finding that decreasing the angle of projection can reduce the spread of the droplets by an order of meters. Finally, we discuss the importance of these findings in the context of informing public health policies and global information campaigns to slow down the spread of respiratory viruses.

Sex differences in the vascular access of hemodialysis patients: a cohort study

Background

We describe differences for probability of receiving a fistula attempt, achieving fistula use, remaining catheter-free and the rate of access-related procedures as a function of sex.

Methods

Prospectively collected vascular access data on incident dialysis patients from five Canadian programs using the Dialysis Measurement Analysis and Reporting System to determine differences in fistula-related outcomes between women and men. The probability of receiving a fistula attempt and the probability of fistula use were determined using binary logistic regression. Catheter and fistula procedure rates were described using Poisson regression. We studied time to fistula attempt and time to fistula use, accounting for competing risks.

Results

We included 1446 (61%) men and 929 (39%) women. Men had a lower body mass index (P < 0.001) and were more likely to have coronary artery disease (P < 0.001) and peripheral vascular disease (p < 0.001). A total of 688 (48%) men and 403 (43%) women received a fistula attempt. Women were less likely to receive a fistula attempt by 6 months {odds ratio [OR] 0.64 [95% confidence interval (CI) 0.52-0.79]} and to achieve catheter-free use of their fistula by 1 year [OR 0.38 (95% CI 0.27-0.53)]. At an average of 2.30 access procedures per person-year, there is no difference between women and men [incidence rate ratio (IRR) 0.97 (95% CI 0.87-1.07)]. Restricting to those with a fistula attempt, women received more procedures [IRR 1.16 (95% CI 1.04-1.30)] attributed to increased catheter procedures [IRR 1.50 (95% CI 1.27-1.78)]. There was no difference in fistula procedures [IRR women versus men 0.96 (95% CI 0.85-1.07)].

Conclusion

Compared with men, fewer women undergo a fistula attempt. This disparity increases after adjusting for comorbidities. Women have the same number of fistula procedures as men but are less likely to successfully use their fistula.

Major risk factors for sexual minority young people's mental and physical health: findings from a county-wide school-based health needs assessment

BACKGROUND

Childhood health is an important adult health predictor. Sexual orientation is increasingly recognized as influential on children and young people's (CYP) mental and physical health.

METHODS

Data came from a cross-sectional survey of year 9 children attending schools in two local authorities in the north-west of England, including mental and physical health indicators, and demographic characteristics including sexual orientation. The sample of 8058 represented 67.8% of the eligible population. Data were analysed by sexual orientation, sexual majority or sexual minority.

RESULTS

Children reporting their sexual orientation as sexual minority reported worse mental and physical health outcomes and behaviours than sexual majority peers; had higher odds of being lonely (odds ratios (OR) = 8.24, 95% C.I.: 6.56-10.37), having self-harmed (OR = 7.28, 95% C.I.: 5.78-9.15), being bullied (OR = 4.76, 95% C.I.: 3.74-6.05) or perceiving themselves as overweight (OR = 2.40, 95% C.I.: 1.89-3.06).

CONCLUSIONS

It is important to identify and support children in a sexual minority. Research is required to understand differences between children within sexual minorities and the impact on outcomes and rights. Health and social policy and services, should respond to the vulnerabilities of sexual minority CYP.

Quantifying the risk of insertion-related peritoneal dialysis catheter complications following laparoscopic placement: Results from the North American PD Catheter Registry

BACKGROUND

Peritoneal dialysis (PD) is a more cost-effective therapy to treat kidney failure than in-center hemodialysis, but successful therapy requires a functioning PD catheter that causes minimal complications. In 2015, the North American Chapter of the International Society for Peritoneal Dialysis established the North American PD Catheter Registry to improve practices and patient outcomes following PD catheter insertion.

AIMS

The objective of this study is to propose a methodology for defining insertion-related complications that lead to significant adverse events and report the risk of these complications among patients undergoing laparoscopic PD catheter insertion.

METHODS

Patients undergoing laparoscopic PD catheter insertion were enrolled at 14 participating centers in Canada and the United States and followed using a Web-based registry. Insertion-related complications were defined as flow restriction, exit-site leak, or abdominal pain at any point during follow-up. We also included infections or bleeding within 30 days of insertion, and any immediate postoperative complications. Adverse events were categorized as PD never starting or termination of PD therapy, delay in the start of PD therapy or interruption of PD therapy, an emergency department visit or hospitalization, or need for invasive procedures. Cause-specific cumulative incidence functions were used to estimate risk.

RESULTS

Five hundred patients underwent laparoscopic PD catheter insertion between 10 November 2015 and 24 July 2018. The cumulative risk of insertion-related complications 6 months from the date of insertion that led to an adverse event was 24%. The risk of flow restriction, exit-site leak, and pain at 6 months was 10.2%, 5.7%, and 5.3%, respectively. PD was never started or terminated in 6.4% of patients due to an insertion-related complication. Leaks and flow restrictions were most likely to delay or interrupt PD therapy. Flow restrictions were the primary cause of invasive procedures. Fifty percent of the complications occurred before the start of PD therapy.

CONCLUSIONS

Insertion-related complications leading to significant adverse events following laparoscopic placement of PD catheters are common. Many complications occur before the start of PD. Insertion-related complications are an important area of focus for future research and quality improvement efforts.

Week 48 Resistance Analyses of the Once-Daily, Single-Tablet Regimen Darunavir/Cobicistat/Emtricitabine/Tenofovir Alafenamide (D/C/F/TAF) in Adults Living with HIV-1 from the Phase III Randomized AMBER and EMERALD Trials

Darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) 800/150/200/10 mg is being investigated in two Phase III trials, AMBER (NCT02431247; treatment-naive adults) and EMERALD (NCT02269917; treatment-experienced, virologically suppressed adults). Week 48 AMBER and EMERALD resistance analyses are presented. Postbaseline samples for genotyping/phenotyping were analyzed from protocol-defined virologic failures (PDVFs) with viral load (VL) ≥400 copies/mL at failure/later time points. Post hoc analyses were deep sequencing in AMBER, and HIV-1 proviral DNA from baseline samples (VL <50 copies/mL) in EMERALD. Through week 48 across both studies, no darunavir, primary PI, or tenofovir resistance-associated mutations (RAMs) were observed in HIV-1 viruses of 1,125 participants receiving D/C/F/TAF or 629 receiving boosted darunavir plus emtricitabine/tenofovir-disoproxil-fumarate. In AMBER, the nucleos(t)ide analog reverse transcriptase inhibitor (N(t)RTI) RAM M184I/V was identified in HIV-1 of one participant during D/C/F/TAF treatment. M184V was detected pretreatment as a minority variant (9%). In EMERALD, in participants with prior VF and genoarchive data (N = 140; 98 D/C/F/TAF and 42 control), 4% had viruses with darunavir RAMs, 38% with emtricitabine RAMs, mainly at position 184 (41% not fully susceptible to emtricitabine), 4% with tenofovir RAMs, and 21% ≥ 3 thymidine analog-associated mutations (24% not fully susceptible to tenofovir) detected at screening. All achieved VL <50 copies/mL at week 48 or prior discontinuation. D/C/F/TAF has a high genetic barrier to resistance; no darunavir, primary PI, or tenofovir RAMs were observed through 48 weeks in AMBER and EMERALD. Only one postbaseline M184I/V RAM was observed in HIV-1 of an AMBER participant. In EMERALD, baseline archived RAMs to darunavir, emtricitabine, and tenofovir in participants with prior VF did not preclude virologic response.

Identifying latent tuberculosis in high-risk populations: systematic review and meta-analysis of test accuracy

BACKGROUND: The relative accuracy of interferon-gamma release assays (IGRAs) and the tuberculin skin test (TST) in identifying latent tuberculosis infection (LTBI) is uncertain.OBJECTIVE: To perform a systematic review and meta-analysis to compare the sensitivity and specificity of IGRAs and TST for the prediction of progression to clinical tuberculosis (TB).METHODS: We searched electronic databases (e.g., MEDLINE and EMBASE) from December 2009 to September 2018 for prospective studies that followed up individuals who had undergone testing with commercial IGRAs and/or TST but had not received treatment based on the test result. The sensitivity and specificity estimates were pooled using a Bayesian bivariate random-effects model.RESULTS: Twenty-five studies, mostly with moderate to high risk of bias and a mean follow-up time ranging from 1 to 5 years were included. TST (10–15 mm) tended to have lower sensitivity and higher specificity than QuantiFERON® Gold In-Tube, T-SPOT®.TB and TST (5 mm). The evidence did not indicate that any test outperformed the others due to wide and overlapping 95% credible intervals.CONCLUSION: The evidence following individuals who had undergone testing for LTBI and had progressed to clinical TB is sparse. We did not find that IGRAs were superior to TST or vice versa; however, as our findings are based on a small number of studies with methodological limitations and great uncertainty around the pooled estimates, the results should be interpreted with caution.

Thermal burns of the spectacle associated with supplementary heating in native New Zealand geckos

Case history: Gradual onset of ocular opacity was observed in three gold-striped geckos (Woodworthia chrysosiretica), and five Pacific geckos (Dactylocnemis pacificus) held in two adjacent terrariums in a zoological institution located in the North Island of New Zealand. Ultraviolet light and heat had been provided for the previous 3-4 years by a fluorescent bulb, but in the last 4 weeks of winter a ceramic heat bulb had been added, situated 10 cm above the upper mesh of the cageClinical findings: All eight geckos presented with mostly bilateral lesions of varying severity confined to the central or upper quadrant of the spectacles. These lesions ranged from variable areas of opacity within the stroma of the spectacle to similarly distributed ulcers of the surface epithelium of both spectacles. The spectacle lesions in the Pacific geckos responded well to treatment with topical combined antimicrobial therapy, within 18-29 days. The gold-striped geckos suffered complications including dysecdysis, severe spectacle ulceration and perforation, mycotic spectaculitis, and widespread mycotic dermatitis resulting in death or leading to euthanasia.Pathological findings: In the three gold-striped geckos, there were extensive areas of deep ulceration and replacement of the spectacle with a thick serocellular crust containing large numbers of fungal elements. The affected areas of the stroma were expanded by large deposits of proteinaceous and mucinous material, pyknotic cellular debris and moderate numbers of heterophils and macrophages as well as infiltrating fungal hyphae.Diagnosis: Mycotic spectaculitis with ulceration and perforation, and disseminated mycotic dermatitis likely secondary to thermal burns.Clinical relevance: This is the first report of thermal burns of the spectacle in any reptile. There was species variation in the burn severity with gold-striped geckos showing more severe lesions, possibly due to a mix of behavioural and anatomical factors. The thermal burns to the spectacles in three cases were complicated by delayed healing, perforation, dysecdysis and severe mycotic infection.

The acoustic emission from asperity interactions in mixed lubrication

Gears typically operate in mixed lubrication conditions, where the lubricant film is too thin to prevent opposing surface asperities from interacting with each other. The likelihood/intensity of interactions is indicated by the Λ ratio: the ratio of smooth surface film thickness to surface roughness. Researchers have asserted that asperity interactions are the predominant cause of acoustic emission (AE) in healthy gear contacts. However, direct experiments on gears have yet to yield a clear relationship between the Asperity AE (AAE) and Λ ratio, this is in part due to the complexity of gear tooth contacts. In this paper, a disc rig was used to simulate a simplified gear contact so that the fundamental relationship between AAE and Λ could be investigated more effectively. By varying oil temperature and entrainment speed, a wide spectrum of lubrication conditions was generated. In contrast to other published studies, an independent measurement technique, the contact voltage (CV), was used to verify the amount of interactions, and repeated roughness measurements were used to confirm minimal surface wear. A simple, consistent and precise relationship between AAE amplitude and Λ was identified and defined for changes from full-film to mixed lubrication. Within the mixed lubrication regime, the AAE amplitude increased exponentially as Λ decreased at all speeds tested. It was also observed that an increase in speed always resulted in an increase in AAE amplitude, independently of any changes in Λ. This direct effect of speed was modelled so that the AAE could be predicted for any combination of speed and Λ within the tested envelope. This paper links gear contact tribology and AE with new precision and clearly demonstrates the potential of using AAE as a sensitive monitoring technique for the lubrication condition of gears.

The Influence of Age on the Likelihood of Catheter-Free Fistula Use in Hemodialysis Patients

Background:

Clinical practice guidelines recommend arteriovenous fistulas as the preferred form of vascular access for hemodialysis. However, some studies have suggested that older age is associated with poorer fistula outcomes.

Objective:

We assessed the impact of age on the outcomes of fistula creation and access-related procedures.

Design:

This was a prospective cohort study using data collected as part of the Dialysis Measurement Analysis and Reporting (DMAR) system.

Setting:

Participating Canadian dialysis programs, including Southern Alberta Renal Program, Manitoba Renal Program, Sunnybrook Health Sciences Centre (Toronto, Ontario), London Health Sciences Centre (London, Ontario), and The Ottawa Hospital (Ottawa, Ontario).

Patients:

Incident hemodialysis patients aged 18 years and older who started dialysis between January 1, 2004, and May 31, 2012.

Measurements:

The primary outcome was the proportion of all first fistula attempts that resulted in catheter-free fistula use, defined as independent use of a fistula for hemodialysis (ie, no catheter in place). Secondary outcomes included the time to catheter-free fistula use among patients with a fistula creation attempt, total number of days of catheter-free fistula use, and the proportion of a patient’s hemodialysis career spent with an independently functioning fistula (ie, catheter-free fistula use).

Methods:

We compared patient characteristics by age group, using t tests or Wilcoxon rank sum tests, and chi-square or Fisher exact tests, as appropriate. Logistic and fractional logistic regression were used to estimate the odds of achieving catheter-free fistula use by age group and the proportion of dialysis time spent catheter-free, respectively.

Results:

A total of 1091 patients met our inclusion criteria (567 age ≥ 65; 524 age < 65). Only 57% of first fistula attempts resulted in catheter-free fistula use irrespective of age (adjusted odds ratio [OR]_≥65vs<65: 1.01; P = .93). The median time from hemodialysis start to catheter-free use of the first fistula did not differ by age when grouped into fistulas attempted pre- and post-dialysis initiation. The adjusted rates of access-related procedures were comparable (incidence rate ratio [IRR]_≥65vs<65: 0.95; P = .32). The median percentage of follow-up time spent catheter-free was similar and low in patients who attempted fistulas (<65 years: 19% vs ≥65 years: 21%; P = .85).

Limitations:

The relatively short follow-up time may have underestimated the benefits of fistula creation and the observational study design precludes inferences about causality.

Conclusions:

In our study, older patients who underwent a fistula attempt were just as likely as younger patients to achieve catheter-free fistula use, within a similar time frame, and while requiring a similar number of access procedures. However, the minority of dialysis time was spent catheter-free.

Timing of Fistula Creation and the Probability of Catheter-Free Use: A Cohort Study

Background:

Fistula creation is recommended to avoid the use of central venous catheters for hemodialysis. The extent to which timing of fistula creation minimizes catheter use is unclear.

Objective:

To compare patient outcomes of 2 fistula creation strategies: fistula attempt prior to the initiation of dialysis (“predialysis”) or fistula attempt after starting dialysis (“postinitiation”).

Design:

Cohort study.

Setting:

Five Canadian dialysis programs.

Patients:

Patients who started hemodialysis between 2004 and 2012, who underwent fistula creation, and were tracked in the Dialysis Measurement Analysis and Reporting (DMAR) system.

Measurements:

Catheter-free fistula use within 1 year of hemodialysis start, probability of catheter-free fistula use during follow-up, and rates of access-related procedures.

Methods:

Retrospective data analysis: logistic regression; negative binomial regression.

Results:

Five hundred and eight patients had fistula attempts predialysis and 583 postinitiation. At 1 year, 80% of those with predialysis attempts achieved catheter-free use compared to 45% with post-initiation attempts (adjusted odds ratio [OR]_preVSpost = 4.67; 95% confidence interval [CI] = 3.28-6.66). The average of all patient follow-up time spent catheter-free was 63% and 28%, respectively (probability of use per unit time, OR_preVSpost = 2.90; 95% CI = 2.18-3.85). This finding was attenuated when accounting for maturation time and when restricting the analysis to those who achieved catheter-free use. Predialysis fistula attempts were associated with lower procedure rates after dialysis initiation—1.61 procedures per person-year compared with 2.55—but had 0.65 more procedures per person prior to starting dialysis.

Limitations:

Observational design, unknown indication for predialysis and postinitiation fistula creation, and unknown reasons for prolonged catheter use.

Conclusions:

Predialysis fistula attempts were associated with a higher probability of catheter-free use and remaining catheter-free over time, and also resulted in fewer procedures compared with postinitiation attempts, which could be due to timing of attempt or patient factors. Catheter use and procedures were still common for all patients, regardless of the timing of fistula creation.

Retrieval of critically ill adults using extracorporeal membrane oxygenation: the nine-year experience in New South Wales

In New South Wales, a coordinated extracorporeal membrane oxygenation (ECMO) retrieval program has been in operation since 2007. This study describes the characteristics and outcomes of patients transported by this service. We performed a retrospective observational study and included patients who were transported on ECMO to either of two adult tertiary referral hospitals in Sydney, New South Wales, between February 28, 2007 and February 29, 2016. One hundred and sixty-four ECMO-facilitated transports occurred, involving 160 patients. Of these, 118 patients (74%) were treated with veno-venous (VV) ECMO and 42 patients (26%) were treated with veno-arterial ECMO. The mean (standard deviation, SD) age was 40.4 (15.0) years. Seventy-seven transports (47%) occurred within metropolitan Sydney, 52 (32%) were from rural or regional areas within NSW, 17 (10%) were interstate transfers and 18 (11%) were international transfers. Transfers were by road (58%), fixed wing aircraft (27%) or helicopter (15%). No deaths occurred during transport. The median (interquartile range) duration of ECMO treatment was 8.9 (5.2-15.3) days. One hundred and nineteen patients (74%) were successfully weaned from ECMO and 109 (68%) survived to hospital discharge or transfer. In patients treated with VV ECMO, age, sequential organ failure assessment score, pre-existing immunosuppressive disease, pre-existing diabetes, renal failure requiring dialysis and failed prone positioning prior to ECMO were independently associated with increased mortality. ECMO-facilitated patient transport is feasible, safe, and results in acceptable short-term outcomes. The NSW ECMO Retrieval Service provides specialised support to patients with severe respiratory and cardiovascular illness, who may otherwise be too unstable to undergo inter-hospital transfer to access advanced cardiovascular and critical care services.

Experimental and Numerical Study of Micropitting Initiation in Real Rough Surfaces in a Micro-elastohydrodynamic Lubrication Regime

Micropitting is a form of surface fatigue damage that happens at the surface roughness scale in lubricated contacts in commonly used machine elements, such as gears and bearings. It occurs where the specific film thickness (ratio of smooth surface film thickness to composite surface roughness) is sufficiently low for the contacts to operate in the mixed lubrication regime, where the load is in part carried by direct asperity contacts. Micropitting is currently seen as a greater issue for gear designers than is regular pitting fatigue failure as the latter can be avoided by control of steel cleanliness. This paper describes the results of both theoretical and experimental studies of the onset of micropitting in test disks operated in the mixed lubrication regime. A series of twin disk mixed-lubrication experiments were performed in order to examine the evolution of micropitting damage during repeated cyclic loading of surface roughness asperities as they pass through the contact. Representative measurements of the surfaces used in the experimental work were then evaluated using a numerical model which combines a transient line contact micro-elastohydrodynamic lubrication (micro-EHL) simulation with a calculation of elastic sub-surface stresses. This model generated time-history of stresses within a block of material as it passes through the contact, based on the instantaneous surface contact pressure and traction at each point in the computing mesh at each timestep. This stress time-history was then used within a shear-strain-based fatigue model to calculate the cumulative damage experienced by the surface due to the loading sequence experienced during the experiments. The proposed micro-EHL model results and the experimental study were shown to agree well in terms of predicting the number of loading cycles that are required for the initial micropitting to occur.