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Dive into the research topics where Roland C. Merchant is active.

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Featured researches published by Roland C. Merchant.


Annals of Emergency Medicine | 2010

Emergency Department Bedside Ultrasonographic Measurement of the Caval Index for Noninvasive Determination of Low Central Venous Pressure

Arun Nagdev; Roland C. Merchant; Alfredo Tirado-Gonzalez; Craig Sisson; Michael Murphy

STUDY OBJECTIVE Among adult emergency department (ED) patients undergoing central venous catheterization, we determine whether a greater than or equal to 50% decrease in inferior vena cava diameter is associated with a central venous pressure of less than 8 mm Hg. METHODS Adult patients undergoing central venous catheterization were enrolled in a prospective, observational study. Inferior vena cava inspiratory and expiratory diameters were measured by 2-dimensional bedside ultrasonography. The caval index was calculated as the relative decrease in inferior vena cava diameter during 1 respiratory cycle. The correlation of central venous pressure and caval index was calculated. The sensitivity, specificity, and positive and negative predictive values of a caval index greater than or equal to 50% that was associated with a central venous pressure less than 8 mm Hg were estimated. RESULTS Of 73 patients, the median age was 63 years and 60% were women. Mean time and fluid administered from ultrasonographic measurement to central venous pressure determination were 6.5 minutes and 45 mL, respectively. Of the 73 participants, 32% had a central venous pressure less than 8 mm Hg. The correlation between caval index and central venous pressure was -0.74 (95% confidence interval [CI] -0.82 to -0.63). The sensitivity of caval index greater than or equal to 50% to predict a central venous pressure less than 8 mm Hg was 91% (95% CI 71% to 99%), the specificity was 94% (95% CI 84% to 99%), the positive predictive value was 87% (95% CI 66% to 97%), and the negative predictive value was 96% (95% CI 86% to 99%). CONCLUSION Bedside ultrasonographic measurement of caval index greater than or equal to 50% is strongly associated with a low central venous pressure. Bedside measurements of caval index could be a useful noninvasive tool to determine central venous pressure during the initial evaluation of the ED patient.


American Journal of Emergency Medicine | 2010

Ultrasound-guided femoral nerve blocks in elderly patients with hip fractures ~,**

Francesca L. Beaudoin; Arun Nagdev; Roland C. Merchant; Bruce M. Becker

OBJECTIVES The primary objective of this study was to determine the feasibility of ultrasound-guided femoral nerve blocks in elderly patients with hip fractures in the emergency department (ED). The secondary objective was to examine the effectiveness of this technique as an adjunct for pain control in the ED. METHODS This prospective observational study enrolled a convenience sample of 13 patients with hip fractures. Ultrasound-guided femoral nerve block was performed on all participants. To determine feasibility, time to perform the procedure, number of attempts, and complications were measured. To determine effectiveness of pain control, numerical rating scores were assessed at baseline and at 15 minutes, 30 minutes, and hourly after the procedure for 4 hours. Summary statistics were calculated for feasibility measures. Wilcoxon matched-pairs signed-rank tests and Friedman analysis of variance test were used to compare differences in pain scores. RESULTS The median age of the participants was 82 years (range, 67-94 years); 9 were female. The median time to perform the procedure was 8 minutes (range, 7-11 minutes). All procedures required only one attempt; there were no complications. After the procedure, there were 44% and 67% relative decreases in pain scores at 15 minutes (P < or = .002) and at 30 minutes (P < or = .001), respectively. Pain scores were unchanged from 30 minutes to 4 hours after the procedure (P < or = .77). CONCLUSIONS Ultrasound-guided femoral nerve blocks are feasible to perform in the ED. Significant and sustained decreases in pain scores were achieved with this technique.


Public Health Reports | 2008

Emergency department patient acceptance of opt-in, universal, rapid HIV screening.

Roland C. Merchant; George R. Seage; Kenneth H. Mayer; Melissa A. Clark; Victor DeGruttola; Bruce M. Becker

Objectives. We assessed emergency department (ED) patient acceptance of opt-in, rapid human immunodeficiency virus (HIV) screening and identified demographic characteristics and HIV testing-history factors associated with acceptance of screening. Methods. A random sample of 18- to 55-year-old ED patients was offered rapid HIV screening. Patient acceptance or decline of screening and the reasons for acceptance or decline were analyzed with multivariable regression models. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated for the logistic regression models. Results. Of the 2,099 participants, 39.3% accepted HIV screening. In a multinomial regression model, participants who were never married/not partnered, did not have private health insurance, and had 12 or fewer years of education were more likely to be screened due to concern about a possible HIV exposure. In a multivariable logistic regression model, the odds of accepting screening were greater among those who were younger than 40 years old (OR=1.61, 95% CI 1.32, 2.00), nonwhite (OR=1.28, 95% CI 1.04, 1.58), not married (OR=1.82, 95% CI 1.44, 2.28), lacking private health insurance (OR=1.40, 95% CI 1.13, 1.74), and who had 12 or fewer years of education (OR=1.43, 95% CI 1.16, 1.75). Despite use of a standardized protocol, patient acceptance of screening varied by which research assistant asked them to be screened. Patients not previously tested for HIV who were white, married, and 45 years or older and who had private health insurance were more likely to decline HIV screening. Conclusions. In an opt-in, universal, ED HIV screening program, patient acceptance of screening varied by demography, which indicates that the impact of such screening programs will not be universal. Future research will need to determine methods of increasing uptake of ED HIV screening that transcend patient demographic characteristics, HIV testing history, and motivation for testing.


Academic Emergency Medicine | 2009

Nomenclature and Definitions for Emergency Department Human Immunodeficiency Virus (HIV) Testing: Report from the 2007 Conference of the National Emergency Department HIV Testing Consortium

Michael S. Lyons; Christopher J. Lindsell; Jason S. Haukoos; Gregory Almond; Jeremy Brown; Yvette Calderon; Eileen Couture; Roland C. Merchant; Douglas A.E. White; Richard E. Rothman

Early diagnosis of persons infected with human immunodeficiency virus (HIV) through diagnostic testing and screening is a critical priority for individual and public health. Emergency departments (EDs) have an important role in this effort. As EDs gain experience in HIV testing, it is increasingly apparent that implementing testing is conceptually and operationally complex. A wide variety of HIV testing practice and research models have emerged, each reflecting adaptations to site-specific factors and the needs of local populations. The diversity and complexity inherent in nascent ED HIV testing practice and research are associated with the risk that findings will not be described according to a common lexicon. This article presents a comprehensive set of terms and definitions that can be used to describe ED-based HIV testing programs, developed by consensus opinion from the inaugural meeting of the National ED HIV Testing Consortium. These definitions are designed to facilitate discussion, increase comparability of future reports, and potentially accelerate wider implementation of ED HIV testing.


Annals of Emergency Medicine | 2012

Increasing Computed Tomography Use for Patients With Appendicitis and Discrepancies in Pain Management Between Adults and Children: An Analysis of the NHAMCS

Daniel S. Tsze; Lisa M. Asnis; Roland C. Merchant; Siraj Amanullah; James G. Linakis

STUDY OBJECTIVE Using a national sample of emergency department (ED) visits, we aim to describe use of CBC, computed tomography (CT), and pain medication among ED visits in which appendicitis was diagnosed. We describe use trends over time and identify use differences between adults and children. METHODS The ED component of the National Hospital Ambulatory Medical Care Survey was analyzed for 1992 through 2006, comprising a sample of 447,011 visits (representing an estimated total of approximately 1.5 billion visits), from which a sample of 1,088 patients (representing an estimated 3.7 million patients) received a diagnosis of appendicitis. The frequency of CBC and CT use and frequency of pain medication administration were determined. Survey-adjusted regression analyses were used to determine the probability of a patient receiving CBC, CT, or pain medication. Use was compared between adults and children. RESULTS During the course of the study, from 1996 to 2006, the percentage of patients with appendicitis who received a CT scan increased from 6.3% (95% confidence interval [CI] 0% to 15.3%) to 69% (95% CI 55.5% to 81.7%) for adults and from 0% to 59.8% (95% CI 31.6% to 87.9%) for children. CBC use for adults increased from 77.2% (95% CI 62.9% to 91.5%) to 92.8% (95% CI 85.8% to 99.7%) and decreased from 89.1% (95% CI 74.9% to 100.0%) to 68.4% (95% CI 41.9% to 94.9%) for children. The use of pain medications increased from 24.8% (95% CI 11.3% to 38.4%) to 69.9% (95% CI 56.7% to 83.1%) for adults and from 27.2% (95% CI 5.7% to 48.8%) to 42.8% (95% CI 18.1% to 67.5%) for children. The proportion of children who received parenteral narcotics (13.7% [95% CI 9.3% to 18.0%]) was less than that of adults (23% [95% CI 18.9% to 27.1%]). CONCLUSION CT use has increased for patients with appendicitis over time, and CBC use remains high. There has been an increase in analgesic administration, but more than half of all patients with appendicitis had not received pain medication over the course of the entire study period. Children received fewer parenteral narcotics than adults and appeared to be preferentially treated with nonparenteral nonnarcotic analgesics.


Academic Emergency Medicine | 2014

Low-dose Ketamine Improves Pain Relief in Patients Receiving Intravenous Opioids for Acute Pain in the Emergency Department: Results of a Randomized, Double-blind, Clinical Trial

Francesca L. Beaudoin; Charlie Lin; Wentao Guan; Roland C. Merchant

OBJECTIVES Low-dose ketamine has been used perioperatively for pain control and may be a useful adjunct to intravenous (IV) opioids in the control of acute pain in the emergency department (ED). The aim of this study was to determine the effectiveness of low-dose ketamine as an adjunct to morphine versus standard care with morphine alone for the treatment of acute moderate to severe pain among ED patients. METHODS A double-blind, randomized, placebo-controlled trial with three study groups was conducted at a large, urban academic ED over a 10-month period. Eligible patients were 18 to 65 years old with acute moderate to severe pain (score of at least 5 out of 10 on the numerical pain rating scale [NRS] and pain duration < 7 days) who were deemed by their treating physician to require IV opioids. The three study groups were: 1) morphine and normal saline placebo (standard care group), 2) morphine and 0.15 mg/kg ketamine (group 1), or 3) morphine and 0.3 mg/kg ketamine (group 2). Participants were assessed at 30, 60, and 120 minutes after study medication administration and received rescue analgesia as needed to target a 50% reduction in pain. The primary outcome measure of pain relief, or pain intensity reduction, was derived using the NRS and calculated as the summed pain-intensity (SPID) difference over 2 hours. The amount and timing of rescue opioid analgesia was evaluated as a secondary outcome. The occurrence of adverse events was also measured. RESULTS Sixty patients were enrolled (n = 20 in each group). There were no differences between study groups with respect to age, sex, race/ethnicity, preenrollment analgesia, or baseline NRS. Over the 2-hour poststudy medication administration period, the SPIDs were higher (greater pain relief) for the ketamine study groups than the control group (standard care 4.0, interquartile range [IQR] = 1.8 to 6.5; group 1 7.0, IQR = 4.3 to 10.8; and group 2 7.8, IQR = 4.8 to 12.8; p < 0.02). The SPIDs for the ketamine groups were similar (p < 0.46). When compared to standard care, group 2 sustained the reduction in pain intensity up to 2 hours, whereas group 1 was similar to standard care by 2 hours. Similar numbers of patients received rescue analgesia: standard care group, seven of 20, 35%; group 1, four of 20, 20%; and group 2, four of 20, 20% (p = 0.48). Among those receiving rescue analgesia, those in the standard care group received analgesia sooner than either low-dose ketamine group, on average. More participants in the low-dose ketamine groups reported dysphoria and dizziness. CONCLUSIONS Low-dose ketamine is a viable analgesic adjunct to morphine for the treatment of moderate to severe acute pain. Dosing of 0.3 mg/kg is possibly more effective than 0.15 mg/kg, but may be associated with minor adverse events. Future studies should evaluate additional outcomes, optimum dosing, and use in specific populations.


Pediatric Emergency Care | 2013

Energy drink and other substance use among adolescent and young adult emergency department patients.

Cotter Bv; Jackson Da; Roland C. Merchant; Kavita M. Babu; Baird; Ted D. Nirenberg; James G. Linakis

Objective This study aimed to understand current patterns of energy drink use and compare the extent of usage of energy drinks and other commonly used and misused substances between adolescent (13–17-years-old) and young adult (18–25-years-old) emergency department (ED) patients. Methods During a 6-week period between June and August 2010, all patients presenting to an adult or pediatric ED were asked to complete a computer-based, anonymous questionnaire regarding use of energy drinks and other substances. Wilcoxon rank-sum, 2-sample tests of binomial proportions, Pearson &khgr;2 testing, and regression models were used to compare energy drink and substance use by age groups. Results Past 30-day energy drink use was greater for young adults (57.9%) than adolescents (34.9%) (P < 0.03). Adolescents typically consumed a mean of 1.5 and young adults a mean of 2.6 energy drinks per day when using energy drinks and drank at most a mean of 2.4 and 2.6 drinks per day, respectively. Among adolescents, energy drink usage was more common than alcohol, “street” or illicit drugs, and tobacco usage, but less common than caffeine product usage. For young adults, energy drink usage was more common than “street” or illicit drugs, but less common than caffeine use, and similar to tobacco and alcohol usage. Young adult energy drink users were more likely than young adult non–energy drink users also to use tobacco and caffeine. Conclusions Energy drink use is common among ED patients. Given the high prevalence of energy drink use observed, emergency physicians should consider the involvement of energy drinks in the presentations of young people.


Clinical Toxicology | 2013

Behavioral and physiologic adverse effects in adolescent and young adult emergency department patients reporting use of energy drinks and caffeine

Deidrya A. E. Jackson; Bradford V. Cotter; Roland C. Merchant; Kavita M. Babu; Janette R. Baird; Ted D. Nirenberg; James G. Linakis

Abstract Introduction. This pilot study assessed the prevalence of physiologic and behavioral adverse effects among adolescent (13–17 years) and adult (18–25 years) emergency department patients who reported energy drink and/or caffeinated-only beverage use within the 30 days prior to emergency department presentation. It was hypothesized that energy drink users would report more adverse effects than those who used only traditional caffeinated beverages such as coffee, tea, or soft drinks. Methods. This cross-sectional pilot study was conducted in two urban emergency departments, one adult and one pediatric. Eligible patients were enrolled during a 6-week period between June and August 2010. Participants completed a tablet computer-based, self-administered, anonymous questionnaire about their past 30-day energy drink and/or caffeinated-only beverage use, substance use, and experience of 10 physiologic and 10 behavioral symptoms. Multivariable logistic regression and negative binomial regression models, adjusted for age, gender, and substance use, were created to compare the occurrence of each adverse effect between energy drink and caffeinated-only beverage users. Odds ratios (ORs) and incidence rate ratios (IRRs) were estimated. Results. Of those enrolled, 53.3% reported consuming energy drinks, 39.1% caffeinated-only beverages, and 7.6% no energy drinks or caffeinated-only beverages within the past 30 days. In multivariable logistic regression models, energy drink users were more likely than caffeinated-only beverage users to report having “gotten into trouble at home, school, or work” in the past 30 days (OR: 3.12 [1.24–7.88]). In the negative binomial regression multivariable models, more behavioral effects were reported among drug users (IRR: 1.50 [1.18–1.93]), and more physiologic effects were reported among tobacco users (IRR: 1.42 [1.13–1.80]) and females (IRR: 1.48 [1.21–1.80]), but not among energy drink users. Conclusions. Energy drink users and substance users are more likely to report specific physiologic and behavioral adverse effects. Emergency department clinicians should consider asking patients about energy drink and traditional caffeine usage and substance use when assessing patient symptoms.


Academic Emergency Medicine | 2003

Emergency Department Blood or Body Fluid Exposure Evaluations and HIV Postexposure Prophylaxis Usage

Roland C. Merchant; Bruce M. Becker; Kenneth H. Mayer; Janene Fuerch; Barbara Schreck

OBJECTIVES To determine the frequency and type of patient visits for blood or body fluid exposures to a large, urban emergency department (ED); to ascertain the frequency that human immunodeficiency virus (HIV) post-exposure prophylaxis (PEP) was prescribed for these exposures; and to compare HIV PEP usage by patient group, occupation, and exposure type. METHODS Retrospective medical record review of ED patient visits (January 1, 1995, through June 30, 2001) extracted from two separate billing record computerized databases using 14 ICD-9 codes that defined blood or body fluid exposures. RESULTS Of the 1,436 visits, 22% were by health care workers (HCWs) and 78% by non-HCW adults, adolescents, or children. Sixty percent of the HCWs sustained needlestick or sharp injuries, 73% of non-HCW adults had human bites, and 81% of adolescents and children had sexual exposures. Nurses were the largest group of HCWs, whereas police, correction officers, and security guards were the largest group of non-HCWs exposed at work. HCWs and non-HCW adults who sustained nonsexual exposures were much more likely to present for an evaluation within 24 hours than adolescents or children who suffered sexual assault (p<0.001). HIV PEP was prescribed 143 times: 92 to HCWs and 51 to all other patients. HIV PEP was most often prescribed to HCWs sustaining needlestick injuries. CONCLUSIONS The majority of patients were not HCWs, which attests to the need for national, nonoccupational blood or body fluid management guidelines. There may be particular groups who would benefit from educational campaigns informing them of the need for early-intervention, postexposure measures to prevent an HIV infection.


BMC Emergency Medicine | 2013

All purulence is local - epidemiology and management of skin and soft tissue infections in three urban emergency departments

Chris Merritt; John P. Haran; Jacob Mintzer; Joseph Stricker; Roland C. Merchant

BackgroundSkin and soft tissue infection (SSTIs) are commonly treated in emergency departments (EDs). While the precise role of antibiotics in treating SSTIs remains unclear, most SSTI patients receive empiric antibiotics, often targeted toward methicillin-resistant Staphylococcus aureus (MRSA). The goal of this study was to assess the efficiency with which ED clinicians targeted empiric therapy against MRSA, and to identify factors that may allow ED clinicians to safely target antibiotic use.MethodsWe performed a retrospective analysis of patient visits for community-acquired SSTIs to three urban, academic EDs in one northeastern US city during the first quarter of 2010. We examined microbiologic patterns among cultured SSTIs, and relationships between clinical and demographic factors and management of SSTIs.ResultsAntibiotics were prescribed to 86.1% of all patients. Though S. aureus (60% MRSA) was the most common pathogen cultured, antibiotic susceptibility differed between adult and pediatric patients. Susceptibility of S. aureus from ED SSTIs differed from published local antibiograms, with greater trimethoprim resistance and less fluoroquinolone resistance than seen in S. aureus from all hospital sources. Empiric antibiotics covered the resultant pathogen in 85.3% of cases, though coverage was frequently broader than necessary.ConclusionsThough S. aureus remained the predominant pathogen in community-acquired SSTIs, ED clinicians did not accurately target therapy toward the causative pathogen. Incomplete local epidemiologic data may contribute to this degree of discordance. Future efforts should seek to identify when antibiotic use can be narrowed or withheld. Local, disease-specific antibiotic resistance patterns should be publicized with the goal of improving antibiotic stewardship.

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Melissa A. Clark

University of Massachusetts Medical School

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