John A. Sellick

The Use of Statistical Process Control Charts in Hospital Epidemiology

Hospital epidemiologists rely on sound scientific and analytical principles in the conduct of surveillance, studies, investigations, etc. The demonstration of differences in occurrence of events (eg, nosocomial infections) in different time periods generally has used traditional hypothesis testing statistical models. However, repetitive hypothesis testing is impractical for frequent analysis of accumulating data, especially when there is no apparent outbreak. Clearly, a statistical procedure that simplifies hypothesis testing to detect acute variations in certain occurrences is desirable. Ongoing analysis of trends also would be desirable. Many United States hospitals have espoused continuous quality improvement (CQI) or similarly identified programs as a means to improve both patient care and operating efficiency. With this trend, the scientific method has become interjected into all aspects of patient management, and no longer is confined to formal research studies. Many scientific quality management techniques that long have been used in industrial settings have been applied to healthcare settings. Noteworthy is the use of statistical methods to describe the variation in processes, which is known as statistical process control (SPC). The term statistical quality control (SQC) often is used interchangeably, but some authors refer to SQC only when statistical methods also are used to improve a process. This article will describe the basic theory and simple application of SPC in hospital epidemiology.

Influence of an educational program and mechanical opening needle disposal boxes on occupational needlestick injuries.

OBJECTIVES To determine whether an educational program had a beneficial impact on healthcare worker needlestick injuries, particularly those caused by recapping. Secondary goals were to evaluate the efficacy of in-room needle-boxes and to determine whether surveillance data were useful when evaluating new products. DESIGN Survey of employee health department reports. SETTING Tertiary care teaching hospital. PARTICIPANTS Healthcare workers who reported needlestick injuries and other blood and body fluid exposures to the employee health department. INTERVENTIONS Exposure data from the 10 months prior to institution of the educational program and installation of disposal boxes were compared with data from the following 27 months. Additionally, the type of disposal box was changed for the last 9 months of the survey. RESULTS Needlestick injuries caused by recapping fell significantly following the educational program (p = .005). However, injuries caused by previously disposed needles protruding into the mechanical opening of the needleboxes increased significantly (p = .002). Following a change of needleboxes to a nonmechanical opening design, the latter type of injury declined (p = .052). Total needlestick injuries, most other categories of needlestick injury, and other exposures did not change significantly during the 37 months of the study. CONCLUSIONS The educational programs appeared to have positive impact on reducing recapping injuries, but many other needlestick categories did not change significantly. Mechanical opening needle disposal boxes appear to present a hazard when compared with fixed opening boxes. Surveillance data appear to be useful in monitoring injuries as well as evaluating products.

Factors Associated with Antibiotic Misuse in Outpatient Treatment for Upper Respiratory Tract Infections

ABSTRACT The Centers for Disease Control and Prevention has promoted the appropriate use of antibiotics since 1995 when it initiated the National Campaign for Appropriate Antibiotic Use in the Community. This study examined upper respiratory tract infections included in the campaign to determine the degree to which antibiotics were appropriately prescribed and subsequent admission rates in a veteran population. This study was a retrospective chart review conducted among outpatients with a diagnosis of a respiratory tract infection, including bronchitis, pharyngitis, sinusitis, or nonspecific upper respiratory tract infection, between January 2009 and December 2011. The study found that 595 (35.8%) patients were treated appropriately, and 1,067 (64.2%) patients received therapy considered inappropriate based on the Get Smart Campaign criteria. Overall the subsequent readmission rate was 1.5%. The majority (77.5%) of patients were prescribed an antibiotic. The most common antibiotics prescribed were azithromycin (39.0%), amoxicillin-clavulanate (13.2%), and moxifloxacin (7.5%). A multivariate regression analysis demonstrated significant predictors of appropriate treatment, including the presence of tonsillar exudates (odds ratio [OR], 0.6; confidence interval [CI], 0.3 to 0.9), fever (OR, 0.6; CI, 0.4 to 0.9), and lymphadenopathy (OR, 0.4; CI, 0.3 to 0.6), while penicillin allergy (OR, 2.9; CI, 1.7 to 4.7) and cough (OR, 1.6; CI, 1.1 to 2.2) were significant predictors for inappropriate treatment. Poor compliance with the Get Smart Campaign was found in outpatients for respiratory infections. Results from this study demonstrate the overprescribing of antibiotics, while providing a focused view of improper prescribing. This article provides evidence that current efforts are insufficient for curtailing inappropriate antibiotic use.

Impact of an Antimicrobial Stewardship Program on Patient Safety in Veterans Prescribed Vancomycin

PURPOSE This study aimed to determine the safety impact of an antimicrobial stewardship program (ASP) on vancomycin-associated nephrotoxicity and to examine risk factors contributing to the development of toxicity. METHODS This was a retrospective chart review of data from 453 veterans receiving vancomycin in the VA Western New York Healthcare System between October 2006 and July 2014. Nephrotoxicity was defined as an increase in serum creatinine of ≥ 0.5 mg/dL or by 50% of baseline for 2 consecutive days. FINDINGS Patients receiving vancomycin after the implementation of the ASP were less likely to develop nephrotoxicity (odds ratio [OR] = 2.06; 95% CI, 1.02-4.28). Nephrotoxicity occurred in 6.84% of patients from the pre-ASP cohort and in 3.75% of patients after the implementation of the ASP. Predictors of nephrotoxicity included hospital service (surgical service, OR = 2.29; 95% CI, 1.13-4.64), elevated maximum trough concentration (unit OR = 1.15; 95% CI, 1.10-1.20), and concurrent piperacillin/tazobactam therapy (OR = 3.21; 95% CI, 1.43-7.96). The number of vancomycin trough concentration measurements per patient did not vary between the pre-ASP and ASP groups. IMPLICATIONS ASPs represent an important aspect of a patient-safety initiative in order to reduce vancomycin-associated nephrotoxicity. Concurrent piperacillin/tazobactam therapy, surgical service, and elevated maximum trough concentration were risk factors for nephrotoxicity.

Impact of Antimicrobial Stewardship on Outcomes in Hospitalized Veterans With Pneumonia

PURPOSE The purpose of this study was to evaluate the impact of an antimicrobial stewardship program (ASP) on outcomes for inpatients with pneumonia, including length of stay, treatment duration, and 30-day readmission rates. METHODS A retrospective chart review comparing outcomes of veterans admitted with pneumonia before (2005-2006) and after (2013-2014) implementation of an ASP was conducted; pneumonia was defined according to International Classification of Diseases, Ninth Revision (ICD-9) codes. Infectious diseases physicians and pharmacist in the ASP provided appropriate recommendations to the primary medicine teams. Bivariate analysis of baseline characteristics and comorbid conditions were performed between the time frames. Least squares regression was used to analyze length of stay, time of IV to PO conversions, and duration of antibiotics. Multivariate logistic regressions were used to determine odds of 30-day readmission and odds of Clostridium difficile infections between time periods. FINDINGS There were 86 patients in the pre-ASP period and 88 patients in the ASP period. Mean length of stay decreased from 8.1 to 6.6 days (P = 0.02), total duration of antibiotic therapy decreased from 12 to 8.5 days (P < 0.0001), and time of IV to PO antibiotic conversions decreased from 5.3 to 3.9 days (P = 0.0003), before ASP and during ASP, respectively. The odds ratio of 30-day readmission before ASP was 2.78 and 0.36 during the ASP (P = 0.05). The odds ratios of Clostridium difficile infections before ASP was 2.08 and 0.48 during the ASP (P = 0.37). IMPLICATIONS The ASP interventions were associated with shorter durations of therapy, shorter lengths of stay, and lower rates of readmission and Clostridium difficile infections within 30 days. Limitations of this study are retrospective cohort design, small study population, limited study population diversity, and non-concurrent cohort times periods.

Obesity and Heart Failure as Predictors of Failure in Outpatient Skin and Soft Tissue Infections

ABSTRACT The purpose of this study was to evaluate risk factors for failure of antibiotic treatment within 30 days for uncomplicated skin infections of outpatients treated in a Veterans Affairs hospital. A retrospective chart review of outpatients between January 2006 and July 2015 with an ICD-9 (International Statistical Classification of Diseases and Related Health Problems) code of cellulitis or abscess was included in the analysis. The primary outcome was success versus failure of the antibiotic, with failure defined as another antibiotic prescribed or hospitalization within 30 days for the original indication. A total of 293 patients were included in the final analysis, 24% of whom failed within 30 days. Obesity/overweight (body mass index [BMI] of >25 kg/m2) was identified in 83% of the overall population, with 16% of that population having a BMI greater than 40 kg/m2. An elevated mean BMI of 34.2 kg/m2 (P = 0.0098) was found in the subset of patients who failed oral antibiotics compared to a BMI of 31.32 kg/m2 in patients who were treated successfully. Additionally, the patients who failed had an increased prevalence of heart failure at 16% (P = 0.027). Using multivariate logistic regression, BMI and heart failure were determined to be significant predictors of antibiotic prescription failure. Each 10-kg/m2 unit increase in BMI was associated with a 1.62-fold-greater odds of failure. A diagnosis of heart failure increased the odds of failure by 2.6-fold (range, 1.1- to 5.8-fold). Outpatients with uncomplicated skin infections with an elevated BMI and heart failure were found to have increased odds of failure, defined as hospitalization or additional antibiotics within 30 days.

Where Do They Come From and Where Do They Go: Implications of Geographic Origins of Medical Students

Background Can prior places of residence listed on a medical school application predict where a physician will practice in midcareer? Method Geographic data were analyzed for a cohort of 399 graduates from a single U.S. medical school. Results Applicants with origins in the local region had a 40.4% to 49.5% probability of practicing locally in midcareer—an increased likelihood of 6.1 to 7.3 (P < .001) by bivariate analysis. In a logistic regression analysis, residence at birth (odds ratio [OR] = 2.6, P = .019) and at college graduation (OR = 2.8, P = .001) were significant predictors of midcareer practice location, but residence at high school graduation and on application to medical school were not. Conclusions Midcareer practice location is related to geographic origins. Using multiple indicators of geographic origins available at the time of application can allow admissions committees to make higher-quality decisions.

Transmission of methicillin-resistant Staphylococcus aureus to health care worker gowns and gloves during care of residents in Veterans Affairs nursing homes

Background: This was an observational study designed to estimate the frequency of methicillin‐resistant Staphylococcus aureus (MRSA) transmission to gowns and gloves worn by health care workers (HCWs) interacting with Veterans Affairs Community Living Center (VA nursing home) residents to inform MRSA prevention policies. Methods: Participants included residents and HCWs from 7 VA nursing homes in 4 states and Washington, DC. Residents were cultured for MRSA at the anterior nares, perianal skin, and wound (if present). HCWs wore gowns and gloves during usual care activities. After each activity, a research coordinator swabbed the HCWs gown and gloves. Swabs were cultured for MRSA. Results: There were 200 residents enrolled; 94 (46%) were MRSA colonized. Glove contamination was higher than gown contamination (20% vs 11%, respectively; P < .01). Transmission varied greatly by type of care from 0%‐19% for gowns and 7%‐37% for gloves. High‐risk care activities (odds ratio [OR] > 1.0, P < .05) for gown contamination included changing dressings (eg, wound), dressing, providing hygiene (eg, brushing teeth), and bathing. Low‐risk care activities (OR < 1.0, P < .05 or no transmission) for gown contamination included glucose monitoring, giving medications, and feeding. Conclusions: MRSA transmission from colonized residents to gloves was higher than transmission to gowns. Transmission to gloves varies by type of care, but all care had a risk of contamination, demonstrating the importance of hand hygiene after all care. Transmission to gowns was significantly higher with certain types of care. Optimizing gown and glove use by targeting high‐risk care activities could improve resident‐centered care for MRSA‐colonized residents by promoting a home‐like environment.

Impact of Penicillin Allergy on Time to First Dose of Antimicrobial Therapy and Clinical Outcomes

PURPOSE The objective of this study was to evaluate the impact of a listed penicillin allergy on the time to first dose of antibiotic in a Veterans Affairs hospital. Additional clinical outcomes of patients with penicillin allergies were compared with those of patients without a penicillin allergy. METHODS A retrospective chart review of veterans admitted through the emergency department with a diagnosis of pneumonia, urinary tract infection, bacteremia, and sepsis from January 2006 to December 2015 was conducted. The primary outcome was time to first dose of antibiotic treatment, defined as the time from when the patient presented to the emergency department to the medication administration time. Secondary outcomes included total antibiotic therapy duration and treatment outcomes, including mortality, length of stay, and 30-day readmission rate. FINDINGS A total of 403 patients were included in the final analysis; 57 patients (14.1%) had a listed penicillin allergy. The average age of the population was 75 years and 99% of the population was male. The mean time to first dose of antibiotic treatment for patients with a penicillin allergy was prolonged compared with those without a penicillin allergy (236.1 vs 186.6 minutes; P = 0.03), resulting in an approximately 50-minute delay. Penicillin-allergic patients were more likely to receive a carbapenem or fluoroquinolone antibiotic (P < 0.0001). IMPLICATIONS Patients with a penicillin allergy had a prolonged time to first dose of antibiotic therapy. No significant differences were found in total antibiotic duration, length of stay, or 30-day readmission rate. The small sample size, older population, and single-center nature of this study may limit the generalizability of the present findings to other populations.

Transmission of resistant Gram-negative bacteria to health care worker gowns and gloves during care of nursing home residents in Veterans Affairs community living centers

ABSTRACT The objectives of the study were to estimate the risk of transmission of antibiotic-resistant Gram-negative bacteria (RGNB) to gowns and gloves (G&G) worn by health care workers (HCWs) when providing care to nursing home residents and to identify the types of care and resident characteristics associated with transmission. A multicenter, prospective observational study was conducted with residents and HCWs from Veterans Affairs (VA) nursing homes. Perianal swabs to detect RGNB were collected from residents. HCWs wore G&G during usual care activities, and the G&G were swabbed at the end of the interaction in a standardized manner. Transmission of RGNB from a colonized resident to G&G by type of care was measured. Odds ratios (ORs) associated with type of care or resident characteristics were estimated. Fifty-seven (31%) of 185 enrolled residents were colonized with ≥1 RGNB. RGNB transmission to HCW gloves or gowns occurred during 9% of the interactions (n = 905): 7% to only gloves and 2% to only gowns. Bathing the resident and providing hygiene and toilet assistance were associated with a high risk of transmission. Glucose monitoring and assistance with feeding or medication were associated with a low risk of transmission. In addition, antibiotic use by the resident was strongly associated with greater transmission (OR, 2.51; P < 0.01). RGNB were transferred to HCWs during ∼9% of visits. High-risk types of care were identified for which use of G&G may be prioritized. Antibiotic use was associated with 2.5 times greater risk of transmission, emphasizing the importance of antibiotic stewardship. (This study has been registered at ClinicalTrials.gov under registration no. NCT01350479.)