Characterizing the process of urgent referrals and transfers to a large tertiary care apheresis centre in Ontario: A retrospective database review.

BACKGROUND: Therapeutic plasma exchange (TPE) and red blood cell exchange (RBCX) are life-saving apheresis procedures offered in 7 Ontario hospitals. Most referrals are directed by CritiCall Ontario (CritiCall), a 24/7 service funded by the Ontario Ministry of Health and Long-Term Care. We used CritiCall data to examine referral requests, acceptances, and transfers for urgent apheresis to our centre. METHODS: Retrospective CritiCall referral and transfer data for urgent apheresis between October 2013 and December 2018 were included. Continuous variables were analyzed by linear regression. Categorical variables were analyzed using nonparametric tests. RESULTS: Eighty-five cases (52 TPE, 33 RBCX) were identified. Median patient age was 52 years (interquartile range [IQR] 32) for TPE, 29 years (IQR 18) for RBCX. Most patients (58%) were female. Total time from referral to arrival at our centre was 243 (IQR 166) minutes. The greatest proportion of this total was from patient acceptance to arrival (169 [IQR 112] minutes). Median distance between referring and accepting centres was 39 (IQR 30) kilometres, with ground transportation used most often. Multiple linear regression examining factors that contribute to total time demonstrated that the number of physicians contacted prior to patient acceptance and inter-hospital distance were independently associated (p = 0.007 and p = 0.048, respectively). INTERPRETATION: Addressing modifiable factors to reduce time is important given that time to initiate treatment is associated with better outcomes. Quality improvement strategies should be aimed at coordinated provincial resource sharing, pairing referrals with nearest available apheresis centres, and creating efficiency in the interval between patient acceptance and arrival.

Bringing Sickle Cell Disease Care Closer to Home: Feasibility and Efficacy of a Quality Improvement Initiative at a Community Hospital.

Comprehensive care for patients with sickle cell disease has been shown to improve morbidity. However, few studies have focused on community hospitals where the burden of disease is highest. From 2017 to 2019, a series of quality improvement interventions was implemented in Brampton, Toronto, ON, Canada, directed toward pediatric and adult sickle cell disease populations. This included a new adult clinic and education directed at patients and healthcare providers. There were 206 visits from 88 unique patients at the clinic and hydroxyurea (HU) uptake increased from 41.0 to 60.0% over that time (p < 0.001). The annual admission rate by adult patients before and after intervention was 90.0 and 75.0% respectively (p = 0.010). The length of stay of pediatric patients decreased from 3.5 to 2.9 days (p = 0.039). These interventions resulted in significant improvements in acute care utilization and HU use by sickle cell disease patients locally, but larger studies are required to confirm these findings.

Deferiprone exerts a dose-dependent reduction of liver iron in adults with iron overload.

OBJECTIVE: While doses of deferiprone up to 75 mg/kg/d have been demonstrated to be effective in cardiac iron removal, their efficacy in the reduction of liver iron has been equivocal. The aim of this study was to evaluate the effect of deferiprone dose on liver iron concentrations in adult iron overload patients. METHODS: A single-centered, retrospective, cohort observational study was conducted involving 71 patients exposed to deferiprone doses up to 113 mg/kg/d between January 2009 and June 2015 for a median of 33 months. RESULTS: At the end of the study period, liver iron measured by R2 MRI was reduced by a mean 1.7 mg/g dw. A dose effect was observed, with incremental reductions of 2.8 mg/g dw in end of study LIC for every 10 mg/kg/d higher dose of deferiprone (P < 0.001). A dose effect was also observed in end of study ferritin and cardiac iron concentration measured by T2* MRI (P < 0.0001 and P = 0.048, respectively). No associations between adverse effects and deferiprone dose were observed, but there was a trend toward higher rates of agranulocytosis at higher doses and two of three hereditary hemochromatosis patients developed this complication. CONCLUSION: The present study failed to demonstrate that the use of deferiprone at >90 mg/kg/d was associated with increased risk of agranulocytosis or neutropenia, but did demonstrate more effective liver iron control in iron overload patients.

An innovative short-stay health care model for treatment of uncomplicated vaso-occlusive crisis in adult sickle cell disease patients in Canada to reduce emergency department utilization.

OBJECTIVES: Patients with sickle cell disease (SCD) with vaso-occlusive crises (VOC) often visit the emergency department (ED) for management of painful episodes. The primary objective of this pilot study was to evaluate the acceptability of a short-stay model for treatment of VOC in SCD outside of the ED in Toronto, Canada. Secondary objectives were to assess patient satisfaction of this model, barriers to its use and comparison of clinical outcomes to a historical control. METHODS: Adult SCD patients with symptoms of an uncomplicated VOC between October 2014 to July 2016 were managed according to best practice recommendations in a short-stay unit as an alternative to the local emergency room. Primary outcome of time to first analgesia, and secondary outcome of discharge rate were compared to a historical control at a local ED from 2009-2012. Satisfaction and barriers to use of the ambulatory care delivery model were assessed by patient survey. RESULTS: Twenty-one visits were recorded at the short-stay unit during the study period. Average time to first opiate dose was 23.5 minutes in the short-stay unit compared to 100.3 minutes in the ED (p4/5 on Likert scale) except for geographic accessibility (85% response rate, n=18). CONCLUSION: This study demonstrated high patient satisfaction and acceptability of a short-stay model for treatment of uncomplicated VOC in adult SCD patients in Toronto, the first of its kind in Canada.

Adult sickle cell disease epidemiology and the potential role of a multidisciplinary comprehensive care center in a city with low prevalence.

The aim of this study was to determine the characteristics of the sickle cell disease population in a city of low prevalence and compare them to those reported in the literature. We performed a retrospective cross-sectional study of all sickle cell disease patients seen in the Calgary Health Region, Calgary, Alberta, Canada from 2006 to 2010. Data on clinical endpoints including emergency department (ED) visits, hospital admissions, transfusions, as well as laboratory parameters were collected. A total of 37 adult sickle cell disease patients were identified. Over 5 years, they were represented by a total of 49.2 ED presentations/year, 29.2 (59.0%) of these requiring admission. Eighty-three percent of these presentations were for acute pain episodes. We concluded that the number of ED visits, hospital admissions and several other parameters in our cohort were similar to those in other centers of higher prevalence. This suggests that guidelines representing regions of high prevalence may be applicable to smaller centers, where patients experience similar clinical outcomes.

Physical nature of signal peptide binding to DmsD.

Here we describe the biophysical characterization of the interaction of the redox enzyme maturation protein DmsD with the signal peptide of its target protein, DmsA. Isothermal titration calorimetry (ITC), size exclusion chromatography (SEC), and an in vitro Far-Western assay is used to show that DmsD binds the twin-arginine signal peptide from DmsA in the micromolar range and in a 1:1 molar ratio. The SEC also shows that there is no oligomerization upon binding. Urea and guanidium hydrochloride denaturation profiles demonstrate the stability of DmsD and give insights on how electrostatic and hydrophobic interactions are important within this binding process. Furthermore, by use of N- and C-terminal fusions of DmsA signal peptide to GST, we observe that N-terminal display of the peptide is important for binding DmsD. In addition, all the folding forms of DmsD were found to bind the DmsA signal peptide as observed with the Far-Western assay.