Jonathan Aboagye

Effectiveness of Prevention Strategies for Contrast-Induced Nephropathy: A Systematic Review and Meta-analysis

Iodine contrast medium is an essential component of many diagnostic and therapeutic procedures that involve medical imaging. One important side effect of iodine contrast is contrast-induced nephropathy (CIN), defined as an increase in serum creatinine levels of more than 25% or 44.2 mol/L (0.5 mg/dL) within 3 days of intravascular administration in the absence of an alternative cause (1). Because of increasing use of contrast media in radiologic and cardiologic procedures and the increasing prevalence of persons who are vulnerable to CIN (those with chronic kidney disease, diabetes mellitus, or hypertension, as well as elderly persons), kidney failure due to CIN is a substantial concern (2, 3). The reported incidence varies between 7% and 11% depending on the definition of CIN, study population, and setting (24). Some studies suggest that this incidence may be overestimated (4), especially when intravenous (IV) contrast media are used. An average additional cost of

Rural-Urban Differences in Access to Specialist Providers of Colorectal Cancer Care in the United States: A Physician Workforce Issue

10345 is associated with a CIN-related hospital stay (5). Many strategies have been used to prevent CIN. They include oral hydration; volume expansion with sodium chloride or bicarbonate or both; administration of N-acetylcysteine; withdrawal of metformin, angiotensin-converting enzyme inhibitors, angiotensin IIreceptor blockers, or nonsteroidal anti-inflammatory drugs; hemofiltration or hemodialysis; statins; use of low-osmolar contrast media (LOCM), iso-osmolar contrast media (IOCM), or nonionic contrast media; and reducing the volume of contrast media administered. Despite these varied strategies, no clear consensus exists in clinical practice about the most effective intervention to prevent or reduce CIN. Many meta-analyses have been published, but almost all of them have focused on specific therapies or included subspecialtyspecific populations, which reduced the general applicability in clinical practice (611). The route of administration of contrast media may be a confounder because the baseline risk profile of patients having intra-arterial (IA) versus IV procedures may differ. Whether effectiveness of preventive interventions depends on the route of administration or the type of contrast media (IOCM or LOCM, the 2 types now in regular clinical use in the United States) is also unclear. We did a systematic review and meta-analysis to compare the preventive effect of strategies to reduce CIN, including subgroup analyses based on route of administration of contrast media or preventive strategies and the type of contrast media used. Methods We developed a protocol for this systematic review, which we posted online and registered in PROSPERO (CRD42013006217). The complete protocol is in the full report on which this article is based (12). Data Sources and Searches We searched MEDLINE, EMBASE, and the Cochrane Library through 30 June 2015 (Appendix Table). In addition, we searched the Scopus database for conference proceedings and other reports. We reviewed the reference lists of relevant articles and related systematic reviews to identify original articles that we might have missed. We also searched ClinicalTrials.gov and the U.S. Food and Drug Administration Web site. Appendix Table. Detailed Search Strategy Study Selection We included studies of patients of all ages. We identified observational and randomized, controlled trials (RCTs) that included administration of N-acetylcysteine, sodium bicarbonate, sodium chloride, statins, or ascorbic acid to prevent CIN. The study groups received IOCM or LOCM via IV or IA injection, CIN outcome was explicitly defined, and sufficient data were reported to calculate the primary effect measure (relative risk reduction of CIN). Secondary outcomes included the need for renal replacement therapy, cardiac events, and mortality. We included only RCTs for the meta-analyses. All data from other studies and other strategies to reduce CIN incidence (such as adenosine antagonists, renal replacement therapy, diuretics, antioxidants, and vasoactive agents) were analyzed and included in the full report (12). We excluded studies of high-osmolar contrast medium because it is no longer used in clinical practice in the United States. We did not contact the authors for original data. Data Extraction and Quality Assessment Two reviewers independently screened the titles and abstracts for eligibility and independently assessed each studys risk of bias by using 5 items from the Cochrane Risk of Bias Tool for RCTs (3). We solved disagreements by consensus or a third reviewer when consensus was not possible. At random intervals during screening, we did quality checks to ensure that eligibility criteria were applied consistently. The second reviewer checked the accuracy of the data extracted by the first reviewer. We graded the strength of evidence (SOE) on comparisons of interest for the key outcomes by using the grading scheme recommended in the Methods Guide of the Evidence-based Practice Center and considered the domains of study limitations, directness, consistency, precision, reporting bias, and magnitude of effect (13). Following the guidance of the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) Working Group (14), we rated evidence as precise if the total number of patients exceeded an optimum information size and the 95% CI excluded a risk ratio (RR) of 1.0. If the number of patients exceeded the optimum information size and the CI did not exclude the possibility of no difference (that is, RR of 1.0), we only rated the evidence as precise if the CI excluded the possibility of a clinically important benefit or harm (that is, RR <0.75 or >1.25). We classified the SOE pertaining to each comparison into 4 category grades (high, moderate, low, and insufficient) and assigned SOE grades by group consensus. The body of evidence was considered high-grade if study limitations were low and there were no problems in any other domain, and it was subsequently downgraded for each domain in which a problem was identified. If the magnitude of effect was very large, the SOE could be upgraded. Data Synthesis and Analysis The primary outcome was CIN, defined as an increase in serum creatinine levels of more than 25% or 44.2 mol/L (0.5 mg/dL) within 3 days of intravascular administration of contrast media. We calculated individual study RRs and CIs and then obtained overall and subgroup summary RRs by using a random-effects model. For large comparisons with 18 or more studies, we used the DerSimonianLaird random-effects estimator, with the estimate of heterogeneity taken from the inverse-variance, fixed-effect model (15). Although this method is often the standard estimator used by many meta-analysis software programs, it tends to underestimate CIs when fewer than 18 studies are compared (15). To compensate, we used the KnappHartung small-sample estimator approach for comparisons with fewer than 18 studies. This method allows for small sample adjustments to the variance estimates and calculates CIs on the basis of the t distribution with k 1 degrees of freedom (15). We used the Harbord modified test for small study effects to determine whether there was asymmetry in effect estimates. To assess the clinical importance of differences in CIN incidence, a binary outcome, we followed guidance for selecting a minimally important difference on the basis of the overall event rate in the studies (14). Our clinical experts decided that a relative risk reduction of 25% would be clinically important, which is consistent with the guidance that suggests a reduction of 20% to 30% in determining optimal information size. To account for factors that could be associated with a difference in CIN risk, we did a subgroup analysis on the basis of the route of administration (IA vs. IV) and type of contrast media (IOCM vs. LOCM), baseline serum creatinine level, sex, age, and prevalence of diabetes mellitus. A priori, we assumed that there would be considerable heterogeneity and therefore used a random-effects model. We also examined the I 2, which measures the degree of heterogeneity across studies (I 2 varies from 0% to 100%, with 0% indicating no heterogeneity). All statistical analyses were done in Stata, version 13 (StataCorp). Role of the Funding Source The Agency for Healthcare Research and Quality selected the topic and assigned it to the Johns Hopkins University Evidence-based Practice Center. The Agency assigned a task order officer who provided comments on the protocol and draft versions of the full evidence report. The Agency did not directly participate in the literature search, determination of study eligibility, data analysis or interpretation, or preparation of the manuscript for publication. Results The literature search revealed 86 RCTs on interventions for preventing CIN (Appendix Figure). These study results were published between 1998 and 2015. Six studies were funded by industry sources (1621), 16 were funded by academia or government agencies, 33 had no funding statement, and the remainder reported no conflicts of interest. All findings from these studies were analyzed and described in the full report (12). Appendix Figure. Summary of evidence search and selection. CIN = contrast-induced nephropathy; RCT = randomized, controlled trial. * 24647 gray literature results were also found. Total does not sum to 371 because the 2 reviewers were not required to agree on reasons for exclusion. N-acetylcysteine Plus IV Saline Versus IV Saline N-acetylcysteine is a direct scavenger of free radicals and improves blood flow through nitric oxidemediated pathways, which results in vasodilatation. As a result, both the antioxidant and vasodilatory properties of N-acetylcysteine are believed to protect against CIN. We included 54 RCTs on N-acetylcysteine plus IV saline versus IV saline with or without a placebo published since 2002 in the meta-analysis (1669). The studies varied widely in patient and intervention characteristic

Extracorporeal membrane oxygenation as a bridge to lung transplantation in the United States: an evolving strategy in the management of rapidly advancing pulmonary disease.

IMPORTANCE Although early detection and treatment of colorectal cancer has been shown to improve outcomes, geographic proximity may influence access to these services. OBJECTIVE To examine the disparities that may exist in colorectal cancer screening and treatment by comparing the distribution of providers of these services in rural and urban counties in the United States. DESIGN, SETTING, AND PARTICIPANTS A retrospective population-based study using data obtained from the 2009 Area Resource File for the entire US population within each county. MAIN OUTCOMES AND MEASURES Counties in the United States were categorized as rural or urban using rural-urban continuum codes as our primary exposure. The proportion of gastroenterologists, general surgeons, and radiation oncologists per 100,000 people in each county was estimated as primary outcomes. Multivariate linear regression analysis adjusted for county-level socioeconomic variables, such as percentages of females, blacks, population without insurance, those with a high school diploma, and median household income, to estimate the relative density of each category of these providers between urban and rural counties. RESULTS In total, 3220 counties were identified, comprising 1807 rural and 1413 urban counties. An unadjusted analysis showed an increased density of gastroenterologists, general surgeons, and radiation oncologists per 100,000 people in urban vs rural counties. A multivariable analysis revealed a significantly higher density of gastroenterologists (1.63; 95% CI, 1.40-1.85; P < .001), general surgeons (2.01; 95% CI, 1.28-2.73; P < .001), and radiation oncologists (0.68; 95% CI, 0.59-0.77; P < .001) per 100,000 people living in urban vs rural counties. CONCLUSIONS AND RELEVANCE A rural-urban disparity exists in the density of gastroenterologists, general surgeons, and radiation oncologists who traditionally provide colorectal cancer screening services and treatment. This might affect access to these services and may negatively influence outcomes for colorectal cancer in rural areas.

Age at presentation of common pediatric surgical conditions: Reexamining dogma

OBJECTIVE Improvements in technology have led to a resurgence in the use of extracorporeal membrane oxygenation as a bridge to lung transplantation. By using a national registry, we sought to evaluate how short-term survival has evolved using this strategy. METHODS With the use of the United Network for Organ Sharing database, we analyzed data from 12,458 adults who underwent lung transplantation between 2000 and 2011. Patients were categorized into 2 cohorts: 119 patients who were bridged to transplantation using extracorporeal membrane oxygenation and 12,339 patients who were not. The study period was divided into four 3-year intervals: 2000 to 2002, 2003 to 2005, 2006 to 2008, and 2009 to 2011. With Kaplan-Meier analysis, 1-year survival was compared for the 2 cohorts of patients in each of the time periods. A propensity score-adjusted Cox regression model was used to estimate the risk of 1-year mortality. RESULTS Of the total number of recipients, 4 (3.4%) were bridged between 2000 and 2002, 17 (14.3%) were bridged between 2003 and 2005, 31 (26.1%) were bridged between 2006 and 2008, and 67 were bridged (56.3%) between 2009 and 2011. Recipients bridged using extracorporeal membrane oxygenation were more likely to be younger and diabetic and to have higher serum creatinine and bilirubin levels. The 1-year survival for those bridged with extracorporeal membrane oxygenation was significantly lower in subsequent periods: 25.0% versus 81.0% (2000-2002), 47.1% versus 84.2% (2006-2008), and 74.4% versus 85.7% (2009-2011). However, this survival progressively increased with each period, as did the number of patients bridged using extracorporeal membrane oxygenation. CONCLUSIONS Short-term survival with the use of extracorporeal membrane oxygenation as a bridge to lung transplantation has significantly improved over the past few years.

Length of Residence in the United States is Associated With a Higher Prevalence of Cardiometabolic Risk Factors in Immigrants: A Contemporary Analysis of the National Health Interview Survey

PURPOSE The commonly cited ages at presentation of many pediatric conditions have been based largely on single center or outdated epidemiologic evidence. Thus, we sought to examine the ages at presentation of common pediatric surgical conditions using cases from large national databases. METHODS A retrospective analysis was performed on Healthcare Cost and Utilization Project databases from 1988 to 2009. Pediatric discharges were selected using matched ICD9 diagnosis and procedure codes for malrotation, intussusception, hypertrophic pyloric stenosis (HPS), incarcerated inguinal hernia (IH), and Hirschsprung disease (HD). Descriptive statistics were computed. RESULTS A total of 63,750 discharges were identified, comprising 2744 cases of malrotation, 5831 of intussusception, 36,499 of HPS, 8564 of IH, and 10,112 of HD. About 58.2% of malrotation cases presented before age 1. Moreover, 92.8% of HPS presented between 3 and 10weeks. For intussusception, 50.3% and 91.4% presented prior to ages 1 and 4years, respectively. Also, 55.8% of IHD cases presented before their first birthday. For HD, 6.5% of cases presented within the neonatal period and 45.9% prior to age 1year. CONCLUSION Our findings support generally cited presenting ages for HPS and intussusception. However, the ages at presentation for HD, malrotation, and IH differ from commonly cited texts.

Helicopter Overtriage in Pediatric Trauma

Background Cardiometabolic risk (CMR) factors including hypertension, overweight/obesity, diabetes mellitus, and hyperlipidemia are high among United States ethnic minorities, and the immigrant population continues to burgeon. Methods and Results Hypothesizing that acculturation (length of residence) would be associated with a higher prevalence of CMR factors, the authors analyzed data on 54, 984 US immigrants in the 2010–2014 National Health Interview Surveys. The main predictor was length of residence. The outcomes were hypertension, overweight/obesity, diabetes mellitus, and hyperlipidemia. The authors used multivariable logistic regression to examine the association between length of US residence and these CMR factors. The mean (SE) age of the patients was 43 (0.12) years and half were women. Participants residing in the United States for ≥10 years were more likely to have health insurance than those with <10 years of residence (70% versus 54%, P<0.001). After adjusting for region of birth, poverty income ratio, age, and sex, immigrants residing in the United States for ≥10 years were more likely to be overweight/obese (odds ratio [OR], 1.19; 95% CI, 1.10–1.29), diabetic (OR, 1.43; 95% CI, 1.17–1.73), and hypertensive (OR, 1.18; 95% CI, 1.05–1.32) than those residing in the United States for <10 years. Conclusions In an ethnically diverse sample of US immigrants, acculturation was associated with CMR factors. Culturally tailored public health strategies should be developed in US immigrant populations to reduce CMR.

Regionalization of the surgical care of children: A risk-adjusted comparison of hospital surgical outcomes by geographic areas

BACKGROUND Helicopter Emergency Medical Services (HEMS) have been designed to provide faster access to trauma center care in cases of life-threatening injury. However, the ideal recipient population is not fully characterized, and indications for helicopter transport in pediatric trauma vary dramatically by county, state, and region. Overtriage, or unnecessary utilization, can lead to additional patient risk and expense. In this study we perform a nationwide descriptive analysis of HEMS for pediatric trauma and assess the incidence of overtriage in this group. METHODS We reviewed records from the American College of Surgeons National Trauma Data Bank (2008-11) and included patients less than 16 years of age who were transferred from the scene of injury to a trauma center via HEMS. Overtriage was defined as patients meeting all of the following criteria: Glasgow Coma Scale (GCS) equal to 15, absence of hypotension, an Injury Severity Score (ISS) less than 9, no need for procedure or critical care, and a hospital length of stay of less than 24 hours. RESULTS A total of 19,725 patients were identified with a mean age of 10.5 years. The majority of injuries were blunt (95.6%) and resulted from motor vehicle crashes (48%) and falls (15%). HEMS transported patients were predominately normotensive (96%), had a GCS of 15 (67%), and presented with minor injuries (ISS<9, 41%). Overall, 28 % of patients stayed in the hospital for less than 24 hours, and the incidence of overtriage was 17%. CONCLUSIONS Helicopter overtriage is prevalent among pediatric trauma patients nationwide. The ideal model to predict need for HEMS must consider clinical outcomes in the context of judicious resource utilization. The development of guidelines for HEMS use in pediatric trauma could potentially limit unnecessary transfers while still identifying children who require trauma center care in a timely fashion.

The Johns Hopkins Venous Thromboembolism Collaborative: Multidisciplinary team approach to achieve perfect prophylaxis.

BACKGROUND There is an ongoing debate among pediatric surgeons regarding the need or lack thereof to centralize the surgical care of children to high-volume childrens centers. Risk-adjusted comparisons of hospitals performing pediatric surgery are needed. METHODS Admissions from 2006 to 2010 from two national administrative databases were analyzed. Only nontrauma pediatric patients undergoing a noncardiac surgical procedure were included. Risk-adjustment was performed with a validated International Classification of Diseases, 9th Revision code-based tool. Hospitals were grouped into metropolitan regions using the first three digits of their zip code. Poorly performing outlier hospitals were defined by an odds ratio >1 and P value <.05 for mortality compared with the center with the greatest pediatric operative volume in that same region. RESULTS Information was obtained from 415,546 pediatric surgical admissions, and 173 hospitals in 55 regions were compared. A total of 18 poor performing hospitals (adjusted odds ratio, range 1.91-35.95) in 15 regions were identified. Mortality in poor performers ranged from 1.11% to 10.19% whereas that in the high-volume reference centers was 0.37-2.41%. A subset analysis in patients <1 year of age showed 37 poor performers in 46 regions. Median number of surgical admissions was 345 (interquartile range 152-907) for nonoutlier and 240 (interquartile range 135-566) for outlier centers (P = .30). CONCLUSION The present analysis is a novel risk-adjusted assessment of the performance of hospitals delivering pediatric surgical care. By identifying the existence of multiple poor performing outlier hospitals, this study provides valuable data for discussion as health care delivery systems continue to debate optimal resource distribution and regionalization of the surgical care of children.

Secondary overtriage in pediatric trauma: can unnecessary patient transfers be avoided?

Venous thromboembolism (VTE) is an important cause of preventable harm in hospitalized patients. The critical steps in delivery of optimal VTE prevention care include (1) assessment of VTE and bleeding risk for each patient, (2) prescription of risk-appropriate VTE prophylaxis, (3) administration of risk-appropriate VTE prophylaxis in a patient-centered manner, and (4) continuously monitoring outcomes to identify new opportunities for learning and performance improvement. To ensure that every hospitalized patient receives VTE prophylaxis consistent with their individual risk level and personal care preferences, we organized a multidisciplinary task force, the Johns Hopkins VTE Collaborative. To achieve the goal of perfect prophylaxis for every patient, we developed evidence-based, specialty-specific computerized clinical decision support VTE prophylaxis order sets that assist providers in ordering risk-appropriate VTE prevention. We developed novel strategies to improve provider VTE prevention ordering practices including face-to-face performance reviews, pay for performance, and provider VTE scorecards. When we discovered that prescription of risk-appropriate VTE prophylaxis does not ensure its administration, our multidisciplinary research team conducted in-depth surveys of patients, nurses, and physicians to design a multidisciplinary patient-centered educational intervention to eliminate missed doses of pharmacologic VTE prophylaxis that has been funded by the Patient Centered Outcomes Research Institute. We expect that the studies currently underway will bring us closer to the goal of perfect VTE prevention care for every patient. Our learning journey to eliminate harm from VTE can be applied to other types of harm. Journal of Hospital Medicine 2016;11:S8-S14.

Airway complications after lung transplantation: Contemporary survival and outcomes.

BACKGROUND In an era of wide regionalization of pediatric trauma systems, interhospital patient transfer is common. Decisions regarding the location of definitive trauma care depend on prehospital destination criteria (primary triage) and interfacility transfers (secondary triage). Secondary overtriage can occur in any resource-limited setting but is not well characterized in pediatric trauma. METHODS The National Trauma Data Bank from 2008 to 2011 was queried to identify patients 15 years or younger who were transferred to pediatric trauma centers. Secondary overtriage was defined as meeting all 4 of the following criteria: injury severity score (ISS) less than 9, no need for surgical procedure, no critical care admission, and length of stay of less than 24 hours. All other transfers were deemed appropriate triage. RESULTS Our definition of secondary overtriage was met in 32,318 patients out of 144,420 transfers (22.4%). Within this group, 37.5% were discharged directly from the emergency department of the receiving hospital without hospital admission. Appropriately triaged patients required a therapeutic procedure in 43.5% of cases. Differences in age, sex, mechanism of injury, and payer status were modest. CONCLUSIONS Secondary overtriage is prevalent in pediatric trauma systems nationwide and is not associated with any particular patient characteristics. Because clinical outcomes and healthcare spending are increasingly scrutinized, secondary overtriage may reflect unnecessary patient transfer and a source of potential cost savings. Development of better guidelines for secondary triage of pediatric trauma patients may enable timely assessment and treatment of children who require a higher level of care while also preventing inefficient use of available resources.