Patricia S. Fontela

Quality and reporting of diagnostic accuracy studies in TB, HIV and malaria: evaluation using QUADAS and STARD standards.

Background Poor methodological quality and reporting are known concerns with diagnostic accuracy studies. In 2003, the QUADAS tool and the STARD standards were published for evaluating the quality and improving the reporting of diagnostic studies, respectively. However, it is unclear whether these tools have been applied to diagnostic studies of infectious diseases. We performed a systematic review on the methodological and reporting quality of diagnostic studies in TB, malaria and HIV. Methods We identified diagnostic accuracy studies of commercial tests for TB, malaria and HIV through a systematic search of the literature using PubMed and EMBASE (2004–2006). Original studies that reported sensitivity and specificity data were included. Two reviewers independently extracted data on study characteristics and diagnostic accuracy, and used QUADAS and STARD to evaluate the quality of methods and reporting, respectively. Findings Ninety (38%) of 238 articles met inclusion criteria. All studies had design deficiencies. Study quality indicators that were met in less than 25% of the studies included adequate description of withdrawals (6%) and reference test execution (10%), absence of index test review bias (19%) and reference test review bias (24%), and report of uninterpretable results (22%). In terms of quality of reporting, 9 STARD indicators were reported in less than 25% of the studies: methods for calculation and estimates of reproducibility (0%), adverse effects of the diagnostic tests (1%), estimates of diagnostic accuracy between subgroups (10%), distribution of severity of disease/other diagnoses (11%), number of eligible patients who did not participate in the study (14%), blinding of the test readers (16%), and description of the team executing the test and management of indeterminate/outlier results (both 17%). The use of STARD was not explicitly mentioned in any study. Only 22% of 46 journals that published the studies included in this review required authors to use STARD. Conclusion Recently published diagnostic accuracy studies on commercial tests for TB, malaria and HIV have moderate to low quality and are poorly reported. The more frequent use of tools such as QUADAS and STARD may be necessary to improve the methodological and reporting quality of future diagnostic accuracy studies in infectious diseases.

Use of continuous positive airway pressure (CPAP) in acute viral bronchiolitis: A systematic review

Continuous positive airway pressure (CPAP), used either alone or associated with heliox (CPAP‐He), has become a popular therapeutic option for bronchiolitis. This systematic review assesses the impact of CPAP on endotracheal intubation, carbon dioxide pressure (PCO2) and respiratory distress in patients with bronchiolitis.

Epidemiology of central line–associated bloodstream infections in Quebec intensive care units: A 6-year review

BACKGROUND The burden of central line-associated bloodstream infections (CLABSI) in Canadian intensive care units (ICUs) is not well established. The present study aimed to describe CLABSI epidemiology in Quebec ICUs during 2003-2009. METHODS The study population was a retrospective dynamic cohort of 58 ICUs that participated in the Surveillance Provinciale des Infections Nosocomiales program during 2003-2009. We calculated annual CLABSI incidence rates (IRs), central venous catheter (CVC) utilization ratios, and case-fatality proportions, and described the pathogens involved. We analyzed data using descriptive statistics and standardized incidence ratios. RESULTS A total of 891 CLABSIs were identified during 446,137 CVC-days. In 2003-2009, CLABSI IRs were 1.67 CLABSI/1,000 CVC-days in adult ICUs, 2.20 CLABSIs/1,000 CVC-days in pediatric ICUs, and 4.40 CLABSIs/1,000 CVC-days in neonatal ICUs. Since 2007, CLABSI IRs in adult, pediatric and neonatal ICUs have decreased by 11%, 50%, and 18%, respectively. Pediatric ICUs had the highest CVC utilization ratio (median, 0.61; interquartile range, 0.57-0.66). Coagulase-negative staphylococci caused 53% of the CLABSIs. The proportion of methicillin-resistant Staphylococcus aureus declined from 70% to <40% after 2006. CONCLUSIONS CLABSIs result in a considerable burden of illness in Quebec ICUs. However, CLABSI IRs have decreased since 2007, and the proportion of methicillin-resistant S aureus has remained <40% since 2006. Continuous surveillance is essential to determine whether these changes are sustainable.

Comparison of pandemic and seasonal influenza in the pediatric emergency department.

Background: Emergency department (ED) presentation of pediatric pandemic H1N1 (pH1N1) infection is not well characterized. Our objective was to describe the clinical manifestations of pH1N1 in the pediatric ED. We also compared these characteristics to seasonal influenza A, and explored risk factors for pH1N1 hospitalization. Methods: We conducted a retrospective cohort study at a pediatric hospital in Quebec City, Canada. Subjects were ED patients aged 0 to 17 years with laboratory-confirmed pH1N1 (April–July 2009) or seasonal influenza A (June 2006–March 2009). Clinical and laboratory data were analyzed by univariate and multivariate log-binomial regression. Results: A total of 127 pH1N1 cases and 110 seasonal influenza cases were identified. pH1N1 patients were older (9.5 vs. 5.6 years; P < 0.0001) and presented more rapidly (2.8 vs. 3.5 days; P = 0.02). Clinical manifestations were similar, although gastrointestinal findings were less frequent in pH1N1 (relative risk [RR]: 0.49; 95% confidence interval [CI]: 0.37–0.65). Hospitalization risk was similar (RR: 1.12; 95% CI: 0.81–1.55), but hospitalized pH1N1 subjects were more frequently diagnosed with pneumonia (RR: 2.41; 95% CI: 1.16–5.00). In a multivariable model, age <2 years was independently associated with pH1N1 hospitalization (RR: 3.17; 95% CI: 1.78–5.65), whereas the absence of significant comorbidities decreased its risk (RR: 0.51; 95% CI: 0.31–0.85). Conclusions: After adjustment for age and delay to presentation, clinical manifestations and 21-day outcomes of pediatric pH1N1 were similar to those of seasonal influenza. pH1N1 patients with previously established risk factors for severe seasonal influenza experienced increased hospitalization risk. Our results suggest that pH1N1 clinical diagnosis and management in the pediatric ED can be performed in a manner similar to seasonal influenza.

Measuring antimicrobial use in hospitalized patients: a systematic review of available measures applicable to paediatrics

OBJECTIVES The optimal measure to use for surveillance of antimicrobial usage in hospital settings, especially when including paediatric populations, is unknown. This systematic review of literature aims to list, define and compare existing measures of antimicrobial use that have been applied in settings that included paediatric inpatients, to complement surveillance of resistance. METHODS We identified cohort studies and repeated point-prevalence studies presenting data on antimicrobial use in populations of inpatients or validations/comparisons of antimicrobial measures through a systematic search of literature using MEDLINE, EMBASE, CINAHL and LILACS (1975-2011) and citation tracking. Study populations needed to include hospitalized paediatric patients. Two reviewers independently extracted data on study characteristics and results. RESULTS Overall, 3878 records were screened and 79 studies met selection criteria. Twenty-six distinct measures were found, the most frequently used being defined daily doses (DDD)/patient-days and exposed patients/patients. Only two studies compared different measures quantitatively, showing (i) a positive correlation between proportion of exposed patients and antimicrobial-days/patient-days and (ii) a strong correlation between doses/patient-days and agent-days/patient-days (r = 0.98), with doses/patient-days correlating more with resistance rates (r = 0.80 versus 0.55). CONCLUSIONS The measure of antimicrobial use that best predicts antimicrobial resistance prevalence and rates, for surveillance purposes, has still not been identified; additional evidence on this topic is a necessity.

A preliminary study of the impact of a handover cognitive aid on clinical reasoning and information transfer.

To assess the impact of a written cognitive aid on expressed clinical reasoning and quantity and the accuracy of information transfer during resident doctor handover.

A survey of Preventive Measures Used and their Impact on Central Line-Associated Bloodstream Infections (CLABSI) in Intensive Care Units (SPIN-BACC)

BackgroundThe Quebec central line-associated bloodstream infections (CLABSI) in intensive care units (ICUs) Surveillance Program saw a decrease in CLABSI rates in most ICUs. Given the surveillance trends observed in recent years, we aimed to determine what preventive measures have been implemented, if compliance to measures was monitored and its impact on CLABSI incidence rates.MethodsAll hospitals participating in the Quebec healthcare-associated infections surveillance program (SPIN-BACC – n = 48) received a 77-question survey about preventive measures implemented and monitored in their ICU. The questionnaire was validated for construct, content, face validity, and reliability. We used Poisson regression to measure the association between compliance monitoring to preventive measures and CLABSI rates.ResultsForty-two (88%) eligible hospitals completed the survey. Two components from the maximum barrier precautions were used less optimally: cap (88%) and full sterile body drape (71%). Preventive measures reported included daily review of catheter need (79%) and evaluation of insertion site for the presence of inflammation (90%). Two hospitals rewired lines even if an infection was suspected or documented.In adult ICUs, there was a statistically significant greater decrease in CLABSI rates in ICUs that monitored compliance to preventive insertion measures, after adjusting for teaching status and the number of hospital beds (p = 0.036).ConclusionsHospitals participating to the SPIN-BACC program follow recommendations for CLABSI prevention, but only a minority locally monitor their application. Compliance monitoring of preventive measures for catheter insertion was associated with a decrease in CLABSI incidence rates.

Determinants of Antibiotic Tailoring in Pediatric Intensive Care: A National Survey*

Objectives: To describe the criteria that currently guide empiric antibiotic treatment in children admitted to Canadian PICUs. Design: Cross-sectional survey. Setting: Canadian PICUs. Subjects: Pediatric intensivists and pediatric infectious diseases specialists. Interventions: None. Measurements and Main Results: We used focus groups and literature review to design the survey questions and its four clinical scenarios (sepsis, pneumonia, meningitis, and intra-abdominal infections). We analyzed our results using descriptive statistics and multivariate linear regression. Our response rate was 60% for pediatric intensivists (62/103) and 36% for pediatric infectious diseases specialists (37/103). Variables related to patient characteristics, disease severity, pathogens, and clinical, laboratory, and radiologic infection markers were associated with longer courses of antibiotics, with median increment ranging from 1.75 to 7.75 days. The presence of positive viral polymerase chain reaction result was the only variable constantly associated with a reduction in antibiotic use (median decrease from, –3.25 to –8.25 d). Importantly, 67–92% of respondents would still use a full course of antibiotics despite positive viral polymerase chain reaction result and marked clinical improvement for patients with suspected sepsis, pneumonia, and intra-abdominal infection. Clinical experience was associated with shorter courses of antibiotics for meningitis and sepsis (–1.3 d [95% CI, –2.4 to –0.2] and –1.8 d [95% CI, –2.8 to –0.7] per 10 extra years of clinical experience, respectively). Finally, site and specialty also influenced antibiotic practices. Conclusions: Decisions about antibiotic management for PICU patients are complex and involve the assessment of several different variables. With the exception of a positive viral polymerase chain reaction, our findings suggest that physicians rarely consider reducing the duration of antibiotics despite clinical improvement. In contrast, they will prolong the duration when faced with a nonreassuring characteristic. The development of objective and evidence-based criteria to guide antibiotic therapy in critically ill children is crucial to ensure the rational use of these agents in PICUs.

A comparison of three dose timings of methylprednisolone in infant cardiopulmonary bypass

Although commonly used in pediatric cardiopulmonary bypass (CPB) optimal dose and timing of steroid administration is unclear. We hypothesized that early administration of a commonly used dose of methylprednisolone given the evening before surgery (ultra-early) would be more effective in decreasing CPB-related inflammatory response than when given at induction of anesthesia (early) or in pump prime (standard).This was a triple-arm, parallel, active control, superiority RCT including 54 infants <2 years old who were randomised to receive 30 mg/kg methylprednisolone at one of the 3 time points. Outcomes included alveolar-arterial oxygen gradient (AaDO2) during, 24, 48 and 72 hours post-CPB, IL-6, IL-8 and reduced (GSH) to oxidized (GSSG) glutathione ratio (pre-ultrafiltration on CPB, end-CPB and 24 hours), PICU length of stay (LOS) and ventilator days. Data were analysed using descriptive statistics and a random effects regression model.The ultra-early group had higher Risk Adjusted Congenital Heart Surgery Score, lower age and longer CPB times than the other groups. No significant differences in AaDO2, IL-8, PICU LOS and ventilator days were observed between groups. Compared to the ultra-early group, the overall rise in IL-6 in the early and standard groups was lower, -27.8 pg/ml (95% CI -52.7,-2.9) and -35.3 pg/ml (95% CI -64.3,-6.34), respectively. GSH:GSSG was significantly lower in the standard group (-35.9; 95% CI -63.31,-8.5) at 24 hours post-CPB.Ultra-early administration of methylprednisolone does not improve AaDO2 post-CPB, nor diminish cytokine release. Lower GSH:GSSG in the standard group suggests less oxidative stress. However despite statistical adjustments conclusions are limited by the unbalanced randomisation of the groups.

Evaluation of the reporting validity of central line-associated bloodstream infection data to a provincial surveillance program.

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