Hospital In Vancouver Research Articles

Prolonged QTc affects short-term and long-term outcomes in patients with normal left ventricular function undergoing cardiac surgery

Although it is known that preoperative decreased left ventricular ejection fraction (LVEF) is a risk for morbidity and mortality after cardiac surgery, there are no reliable markers of risk in patients with preserved LVEF. This study examines whether a prolonged QTc interval is associated with adverse outcomes in patients with preoperative LVEF greater than 40% undergoing cardiac surgery. A retrospective chart review of patients who had cardiac surgery at St. Paul's Hospital in Vancouver, Canada, between 2004 and 2009, who had a preoperative LVEF greater than 40%, was undertaken. We tested for association of preoperative prolonged QTc interval with mortality and morbidity using unadjusted and adjusted analyses. Five-hundred and fifty-five patients with a preoperative LVEF greater than 40% were included in the study; 496 (89.4%) had cardiopulmonary bypass and the remainder were off pump. Preoperative prolonged QTc was associated with increased mortality at 30 days (P<.01), 90 days (P<.01), and 8 years (P<.01), and theseresults remained significant after adjusting for the clinical variables significantly associated with mortality (8-year odds ratio, 2.42; 95% confidence interval, 1.34-4.34; P=.003). Similar results were found when the analysis was restricted to the more homogeneous group of patients undergoing on-pump coronary artery bypass (CABG, n=408). Prolonged QTc was also associated with prolonged intensive care unit stay (P=.02), prolonged hospital stay (P<.01), development of atrial arrhythmias (P=.02), and low cardiac output syndrome (on-pump CABG, P=.02). In patients undergoing cardiac surgery and a preoperative LVEF greater than 40%, a prolonged QTc interval is associated with increased short-term and long-term mortality and increased perioperative morbidity, and therefore should be considered when assessing risk preoperatively.

Economic analysis of vancomycin-resistant enterococci at a Canadian hospital: assessing attributable cost and length of stay

Competing resource demands have resulted in the de-escalation of vancomycin-resistant enterococcus (VRE) control programmes in some Canadian healthcare centres. To determine the attributable costs and length of stay (LOS) of VRE colonizations/infections in an acute care hospital in Canada. Surveillance and financial hospital-based databases were used to conduct analyses with cases and controls from fiscal year 2008-2009 (1 April 2008 to 31 March 2009) at an acute care hospital in downtown Vancouver, Canada. A statistical analysis of attributable costs and LOS was conducted using a generalized linear model. In a secondary analysis, differences in costs and LOS were examined for VRE infections versus colonizations. A total of 217 patients with VRE and a random sample of 1075 patients without VRE were examined. VRE has a positive and significant impact on patient hospitalization costs and LOS. Overall, the presence of VRE increased the estimated mean cost per patient by 61.9% (95% confidence interval: 42.3-84.3) in relative terms and $17,949 (13,949-21,464) in absolute Canadian dollars. For LOS, the attributable number of days associated with a VRE case mean was 68.0% (41.9-98.9) higher in relative terms and 13.8 days (10.0-16.9) in absolute days. In the secondary analysis comparing VRE infection and colonization costs, no statistically significant difference was found. Based on this analysis, the attributable cost and LOS of VRE are considerable. These factors should be considered before de-escalation of a hospital VRE control programme.

Reduction in community-onset methicillin-resistant Staphylococcus aureus rates in an urban Canadian hospital setting

Community-onset methicillin resistant Staphylococcus aureus (CO-MRSA) became a prominent cause of infection in North America in 2003, with a peak in the epidemic noted by multiple groups in the USA between 2005 and 2007. We reviewed rates of MRSA in two hospitals in Vancouver, Canada, to observe changes in epidemiology from 2003 to 2011. Episodes of emergency department (ED) MRSA bacteraemia and wounds were extracted from the laboratory database, with rates calculated per 10,000 ED visits. All cases were assumed to be community onset, as they were diagnosed in the ED. A peak in ED MRSA bacteraemias occurred in 2005, at 7·8/10,000 ED visits. By 2011, rates of ED bacteraemia declined significantly to 3·3/10,000 ED visits (P<or=0·03). MRSA wound rates peaked at 82·2 cases/10,000 ED visits in 2007 with a subsequent significant decline to 34·3 cases in 2011 (P=0·04). We have demonstrated a significant decline in CO-MRSA within our population, consistent with reports from the USA, suggesting a substantial change in the epidemiology of CO-MRSA in certain North American cities.

Polymerase chain reaction assay to detect Clostridium difficile tcdC variants is valuable in characterizing hospital epidemiology

The epidemiology of nosocomial Clostridium difficile infection (CDI), acquired at two hospitals in Vancouver over a one-year period, was reviewed. Cases were analysed by tcdC polymerase chain reaction, with tcdC variants (18 base pair deletion) highly associated with the NAP1 strain. Of the 214 cases identified, 51.9% were caused by these tcdC variants; these cases occurred more frequently in older patients admitted to the community hospital where the strain was endemic. Overall, at least five out of 24 cases classified as recurrences by surveillance definitions were reinfections. Molecular testing allowed identification of major epidemiological differences between the hospitals studied and provided more accurate classification of CDI cases.

Su1469 Efficacy of Radiofrequency Ablation in Management of Barrett's Esophagus: Real-Life Experience of Two Western Canadian Centers

Su1469 Efficacy of Radiofrequency Ablation in Management of Barrett's Esophagus: Real-Life Experience of Two Western Canadian Centers

Predictors of emergency cesarean delivery among international migrant women in Canada

ObjectiveTo determine the predictors of emergency cesarean delivery among international migrant women. MethodsBetween February 2006 and May 2009, 1025 postpartum migrant women were recruited from 12 hospitals in Toronto, Montreal, and Vancouver. Logistic regression was used to model migration, social, health service, and biomedical factors predictive of emergency cesarean. ResultsOverall, 14% percent of participants underwent emergency cesarean. The greatest risk was for women having their first delivery (odds ratio [OR], 5.9; 95% confidence interval [CI], 3.1–11.3); newborns weighing 4000g or more (OR, 3.5; 95% CI, 1.9–6.5); no health insurance (OR, 2.8; 95% CI, 1.2–6.4); delivery on a Friday (OR, 2.2; 95% CI, 1.2–3.9); incomes of less than 30 000 Canadian dollars (OR, 1.9; 1.2–3.0); and induced labor (OR, 1.8; 95% CI, 1.1–3.0). Compared with immigrants, asylum seekers (OR, 0.3; 95% CI, 0.2–0.6) and refugees (OR, 0.5; 95% CI, 0.2–1.0) were protected against emergency cesarean. ConclusionIndicators specific to, or more common among, migrants were informative in assessing the likelihood of emergency cesarean. The risk associated with being uninsured, day of delivery, income, and immigration class suggests the importance of considering non-biomedical factors in reducing the need for emergency cesarean among migrants.

Editorial introductions

Editorial introductions

Re: Schweitzer T, Bohm H, Meyer-Marcotty P, Collmann H, Ernestus RI, Krauss J (2012) Avoiding CT scans in children with single-suture craniosynostosis. Childs Nerv Syst 28: 1077–1082

Dear Editor: I wish to complement Dr. Schweitzer and his colleagues on the report of their experience with the management of children with single-suture craniosynostosis [2]. I strongly agree with the authors that CT scans are rarely necessary for evaluation of these single-suture craniosynostosis. In fact, in 2006 we reported our series of isolated sagittal synostosis and showed that it was possible to accurately diagnose the condition based on clinical findings only [1]. Like the authors, we were concerned about the potential risks of radiation from a CT scan, especially in infancy. We concluded then that “Accurate diagnosis of isolated sagittal synostosis can be made clinically, and operative correction can proceed without a need for radiological investigations, unless the clinical features are not completely typical. This approach could result in significantly reduced radiation exposure for the developing brain and could provide economic benefits to health care providers.” We stand by these conclusions and at BC Children’s Hospital in Vancouver we continue to avoid CT scans in almost all cases of isolated single-suture craniosynostosis. We are pleased that others, such as Schweitzer and colleagues are doing the same. We hope that others will follow their lead. Paul Steinbok

“They silently live in terror…” why sleep problems and night-time related quality-of-life are missed in children with a fetal alcohol spectrum disorder

Children and adolescents with a Fetal Alcohol Spectrum Disorder (FASD) are at high-risk for developing sleep problems (SPs) triggering daytime behavioral co-morbidities such as inattention, hyperactivity, and cognitive and emotional impairments. However, symptoms of sleep deprivation are solely associated with typical daytime diagnosis, such as attention deficit hyperactivity disorder (ADHD) and treated with psychotropic medications. To understand how and why SPs are missed, we conducted qualitative interviews (QIs) with six parents and seven health care professionals (HCPs), and performed comprehensive clinical sleep assessments (CCSAs) in 27 patients together with their caregivers referred to our clinic for unresolved SPs. We used narrative schema and therapeutic emplotment in conjunction with analyzes of medical records to appropriately diagnose SPs and develop treatment strategies. The research was conducted at British Columbia Children's Hospital in Vancouver (Canada) between 2008 and 2011. In the QIs, parents and HCPs exhibited awareness of the significance of SPs and the effects of an SP on the daytime behaviors of the child and the associated burdens on the parents. HCPs' systemic inattention to the sequelae of SPs and the affected family's wellbeing appears due to an insufficient understanding of the various factors that contribute to nighttime SPs and their daytime sequelae. In the CCSAs, we found that the diagnostic recognition of chronic SPs in children and adolescents was impaired by the exclusive focus on daytime presentations. Daytime behavioral and emotional problems were targets of pharmacological treatment rather than the underlying SP. Consequently, SPs were also targeted with medications, without investigating the underlying problem. Our study highlights deficits in the diagnostic recognition of chronic SPs among children with chronic neurodevelopmental disorders/disabilities and proposes a clinical practice strategy, based on therapeutic emplotment that incorporates patients and parents' contributions in recognizing SPs and related sequelae in designing appropriate treatment and care.

Auricular acupuncture for chemically dependent pregnant women: a randomized controlled trial of the NADA protocol

BackgroundThe prevalence of maternal drug use during pregnancy in North America has been estimated to be as high as 6-10%. The consequences for the newborn include increased risk for perinatal mortality and ongoing physical, neurobehavioral, and psychosocial problems. Methadone is frequently used to wean women off street drugs but is implicated as a cause of adverse fetal/neonatal outcomes itself. The purpose of our study was to test the ability of maternal acupuncture treatment among mothers who use illicit drugs to reduce the frequency and severity of withdrawal symptoms among their newborns.MethodsWe randomly assigned chemically dependent pregnant women at BC Women’s Hospital in Vancouver, British Columbia to daily acupuncture treatments versus usual care. By necessity, neither our participants nor acupuncturists were blinded as to treatment allocation. Our primary outcome was days of neonatal morphine treatment for symptoms of neonatal withdrawal. Secondary neonatal outcomes included admission to a neonatal ICU and transfer to foster care.ResultsWe randomized 50 women to acupuncture and 39 to standard care. When analyzed by randomized groups, we did not find benefit of acupuncture; the average length of treatment with morphine for newborns in the acupuncture group was 2.7 (6.3) compared to 2.8 (7.0) in the control group. Among newborns of women who were compliant with the acupuncture regime, we observed a reduction of 2.1 and 1.5 days in length of treatment for neonatal abstinence syndrome compared to the non-compliant and control groups, respectively. These differences were not statistically significant.ConclusionsAcupuncture may be a safe and feasible treatment to assist mothers to reduce their dosage of methadone. Our results should encourage ongoing studies to test the ability of acupuncture to mitigate the severity of neonatal abstinence syndrome among their newborns.Clinical Trial Registrationhttp://www.clinicaltrials.gov registry: W05-0041

Prediction of Repeat Visits by Victims of Intimate Partner Violence to a Level III Trauma Centre

Background. The purpose of this study was to describe and contrast the population of persons presenting to a Vancouver hospital emergency department two or more times with those presenting once.Methods. Subjects for this study had disclosed intimate partner violence on at least one visit to Vancouver General Hospital Emergency Department during the study period 1997–2009. We compared sociodemographic characteristics, presenting complaints and disposition on discharge among single versus repeat visitors.Results. We identified 2246 single visitors and 257 repeat visitors. In a multivariate model, repeat visitors to the ER were more likely to be of First Nations (aboriginal) status, odds ratio (OR) 2.29, 95% confidence intervals (1.30–4.01); to have had a history of previous abuse 3.38 (1.88–6.08); to have received threats of homicide 2.98 (1.74–5.08); and to present with mental illness 3.03 (1.59–5.77). Police involvement was protective against repeat visits 0.54 (0.36–0.98).Conclusion. Persons with potential for multiple visits to the emergency room can be characterized by a number of factors, the presence of which should trigger targeted assessment for violence exposure in settings where assessment is not routine.

Pediatric Compartment Syndrome Caused by Intravenous Infiltration

Department of Biomedical Engineering St. Paul’s Hospital Vancouver, BC [email protected] Conflicts of interest and sources of funding: none declared.

Development and Validation of a Novel Vancomycin Dosing Nomogram for Achieving High-Target Trough Levels at 2 Canadian Teaching Hospitals

Recent guidelines recommend a vancomycin trough (predose) level between 15 and 20 mg/L in the treatment of invasive gram-positive infections, but most initial dosing nomograms are designed to achieve lower targets (5-15 mg/L). Clinicians need guidance about appropriate initial dosing to achieve the higher target. To develop and validate a high-target vancomycin dosing nomogram to achieve trough levels of 15-20 mg/L. A retrospective study was conducted at 2 teaching hospitals, St Paul's Hospital and Vancouver General Hospital in Vancouver, British Columbia. Patients who were treated with vancomycin between January 2008 and June 2010 and who had achieved a trough level of 14.5-20.5 mg/L were identified. Demographic and clinical data were collected. Multiple linear regression was used to develop a vancomycin dosing nomogram for each hospital site. An integrated nomogram was constructed by merging the data from the 2 hospitals. A unique set of patients at each institution was used for validating their respective nomograms and a pooled group of patients for validating the integrated nomogram. Predictive success was evaluated, and a nomogram was deemed significantly different from another nomogram if p < 0.05 via "χ(2) testing. Data from 78 patients at one hospital and 91 patients at the other were used in developing the respective institutional nomograms. For each hospital's data set, both age and initial serum creatinine were significantly associated with the predicted dosing interval (p < 0.001). Validation in a total of 105 test patients showed that the integrated nomogram had a predictive success rate of 56%. A novel vancomycin dosing nomogram was developed and validated at 2 Canadian teaching hospitals. This integrated nomogram is a tool that clinicians can use in selecting appropriate initial vancomycin regimens on the basis of age and serum creatinine, to achieve high-target levels of 15-20 mg/L. The nomogram should not replace clinical judgment for patients with unstable and/or reduced renal function.

Ambient Ozone as a Risk Factor for ED Visits for Cellulitis

Ambient air pollution and weather conditions may affect the number of daily emergency department (ED) visits for skin bacterial infections. The aim of this study was to assess the potential relationship between the odds of an ED visit for cellulitis and the concentration of ambient ozone (O3). The data employed in the study covered ED visits for cellulitis at a Vancouver hospital in the period of January 1999 to February 2003 (1520 days, N = 9,857). A conditional logistic regression model was built to estimate odds ratios (OR) and their 95% confidence intervals (95% CI). The model was adjusted for temperature and humidity. The results are reported for one interquartile range (IQR) of ozone concentrations (IQR = 10.9 ppb). An increase by one IQR in daily ozone concentrations lagged by 3 days was significantly associated with an increase in the odds of ED visit for cellulites: among male patients OR=1.06 (95% CI: 1.01-1.13) and among female patients in the warm period (April-September) OR=1.20 (95% CI: 1.06-1.48). Patients aged 50 or less showed increased odds. Some cases of cellulitis may be associated with exposure to ambient ground-level ozone.

Effect of Misalignment between Hospital and Provincial Formularies on Medication Discrepancies at Discharge: PPITS (Proton Pump Inhibitor Therapeutic Substitution) Study

Medication discrepancies may occur on admission, transfer, or discharge from hospital. Therapeutic interchange within a drug class is a common practice in hospitals, and orders for specific proton pump inhibitors (PPIs) are often substituted with the hospital's formulary PPI through therapeutic interchange protocols. Rabeprazole is the PPI on the formulary of the British Columbia PharmaCare program. However, different PPIs may appear on the formularies of the province's hospitals. This misalignment and use of therapeutic interchange may lead to increased rates of medication discrepancies at the time of discharge. To evaluate the effect of formulary misalignment for PPIs between St Paul's Hospital in Vancouver and the British Columbia PharmaCare program and use of therapeutic interchange on the occurrence of medication discrepancies at discharge. A cohort chart review was performed to compare discharge discrepancy rates for PPI orders between 2 periods: June 2006 to June 2008, when the same PPI appeared on the hospital and provincial formularies, and July 2008 to July 2010, when the designated PPIs differed between the hospital and provincial formularies. Data for the first study period were used to establish the baseline discharge discrepancy rate, and data for the later period represented the discharge discrepancy rate in the presence of misalignment between the hospital and PharmaCare formularies. The discharge discrepancy rate for PPIs was 27.3% (24/88) when the 2 formularies were aligned and 49.1% (81/165) when the formularies were misaligned. This represents an absolute increase of 21.8 percentage points in the risk of discharge discrepancies (95% confidence interval 9.8-33.9 percentage points; p < 0.001) when the hospital and provincial formularies were misaligned and the hospital's therapeutic interchange protocol was used. Misalignment between the PPIs specified in the hospital and provincial formularies, combined with use of therapeutic interchange, was associated with a significant increase in medication discrepancies at discharge.

PH1N1

University of British Columbia British Columbia Children's Hospital Vancouver, British Columbia, Canada * See also p. e78. The author has not disclosed any potential conflicts of interest.

Editorial introductions

Editorial introductions

In response

British Columbia Children's Hospital Vancouver, BC, Canada University of British Columbia Vancouver, BC, Canada Disclosure: The authors declare no conflict of interest.

Sulfur Dioxide and Emergency Department Visits for Stroke and Seizure

The purpose of this study was to assess an association between ambient sulfur dioxide and the number of emergency department (ED) visits for ischemic stroke and seizure. The study used data collected in a Vancouver (Canada) hospital in the years 1999–2003. Daily ED visits diagnosed as ministroke, stroke, or seizure were investigated using the case-crossover technique. Conditional logistic regression models were applied to estimate the odds ratios (ORs) and their respective 95% confidence intervals (CIs). The models included temperature and relative humidity in the form of natural splines. The results were reported for an increase in interquartile range ((IQR), IQR = 1.9 ppb for SO2). Positive and statistically significant associations were obtained for SO2 and ischemic stroke for all patients (OR = 1.12; CI 1.02, 1.23; lag 3) and for female patients (OR = 1.17; CI 1.01, 1.33; lag 0). In the case of ED visits for seizure, for female patients the results were also statistically significant (OR = 1.15; CI 1.02, 1.28; lag 1 and OR = 1.18; CI 1.05, 1.32; lag 2). These findings suggest that cases of ischemic cerebrovascular accidents are associated with acute exposure to ambient sulfur dioxide.

HIV-Associated Thrombotic Thrombocytopenic Purpura

Abstract 4677Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening form of microangiopathic hemolysis that can be associated with HIV infection, and has previously been reported to be associated with low CD4 counts. The existing literature on HIV-TTP is very small and largely made up of small case series generated through databases of patients with HIV. As a result, reports have tended to focus on HIV parameters with limited information available regarding the presentation, management and outcome of the TTP itself. We conducted a retrospective review of TTP cases referred to the pheresis units St. Michael's Hospital and Vancouver General Hospital in Vancouver between July 1993 and May 2011. Ten cases of HIV associated TTP were identified (8 male; 2 female). Median age at presentation was 38 years. One patient had been previously diagnosed and treated for TTP at a different institution. Average duration of HIV infection prior to TTP diagnosis was 5 years (range 0 to 11). Median CD4 count at TTP diagnosis was 79 × 106/ml (range 2 to 326). Median platelet count at presentation was 14 × 106/ml (range 5 to 233), median haemoglobin was 74 g/L (range 61 to 133), all patients had an LDH > 2x the upper limit of normal, and all for whom data was available (8/10) had fragmentation on blood film. Creatinine was elevated in 9 of 10 patients. ADAMTS13 was assessed in 3 of 10 patients and was deficient in one. Five of 10 patients had fever. At presentation, 6 of 10 patients had neurological symptoms (most commonly seizures and/or confusion), but none suffered permanent neurological deficits. All patients were treated with plasmapheresis and received a median of 16 exchanges (2-56). Four patients received concurrent steroids, two patients received IVIG, and one patient received pheresis, steroids IVIG, vincristine and rituximab. Eight of 10 patients achieved complete remissions, one patient achieved a partial response, and one died on treatment. Four of the responding patients subsequently relapsed (0.6 to 13.8 months after the initial episode of TTP); two achieved second remissions, and two died on treatment. In conclusion, our series of HIV associated-TTP confirms previous reports that HIV-TTP tends to occur in patients with CD4 counts less than 200. Complete remissions can be achieved with standard management. However, based on our small series, relapses may be more common and mortality greater than in the general TTP population. Disclosures:Leitch: Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees.