Allen Ma

Indwelling Urinary Catheter Use in the Postoperative Period: Analysis of the National Surgical Infection Prevention Project Data

OBJECTIVES To describe the frequency and duration of perioperative catheter use and to determine the relationship between catheter use and postoperative outcomes. DESIGN Retrospective cohort study. SETTING Two thousand nine hundred sixty-five acute care US hospitals. PATIENTS Medicare inpatients (N = 35 904) undergoing major surgery (coronary artery bypass and other open-chest cardiac operations; vascular surgery; general abdominal colorectal surgery; or hip or knee total joint arthroplasty) in 2001. Main Outcome Measure Postoperative urinary tract infection. RESULTS Eighty-six percent of patients undergoing major operations had perioperative indwelling urinary catheters. Of these, 50% had catheters for longer than 2 days postoperatively. These patients were twice as likely to develop urinary tract infections than patients with catheterization of 2 days or less. In multivariate analyses, a postoperative catheterization longer than 2 days was associated with an increased likelihood of in-hospital urinary tract infection (hazard ratio, 1.21; 95% confidence interval [CI], 1.04-1.41) and 30-day mortality (parameter estimate, 0.54; 95% CI, 0.37-0.72) as well as a decreased likelihood of discharge to home (parameter estimate, - 0.57; 95% CI, - 0.64 to - 1.51). CONCLUSIONS Indwelling urinary catheters are routinely in place longer than 2 days postoperatively and may result in excess nosocomial infections. The association with adverse outcomes makes postoperative catheter duration a reasonable target of infection control and surgical quality-improvement initiatives.

Use of Medicare diagnosis and procedure codes to improve detection of surgical site infections following hip arthroplasty, knee arthroplasty, and vascular surgery

OBJECTIVE To evaluate the use of routinely collected electronic health data in Medicare claims to identify surgical site infections (SSIs) following hip arthroplasty, knee arthroplasty, and vascular surgery. DESIGN Retrospective cohort study. SETTING Four academic hospitals that perform prospective SSI surveillance. METHODS We developed lists of International Classification of Diseases, Ninth Revision, and Current Procedural Terminology diagnosis and procedure codes to identify potential SSIs. We then screened for these codes in Medicare claims submitted by each hospital on patients older than 65 years of age who had undergone 1 of the study procedures during 2007. Each site reviewed medical records of patients identified by either claims codes or traditional infection control surveillance to confirm SSI using Centers for Disease Control and Prevention/National Healthcare Safety Network criteria. We assessed the performance of both methods against all chart-confirmed SSIs identified by either method. RESULTS Claims-based surveillance detected 1.8-4.7-fold more SSIs than traditional surveillance, including detection of all previously identified cases. For hip and vascular surgery, there was a 5-fold and 1.6-fold increase in detection of deep and organ/space infections, respectively, with no increased detection of deep and organ/space infections following knee surgery. Use of claims to trigger chart review led to confirmation of SSI in 1 out of 3 charts for hip arthroplasty, 1 out of 5 charts for knee arthroplasty, and 1 out of 2 charts for vascular surgery. CONCLUSION Claims-based SSI surveillance markedly increased the number of SSIs detected following hip arthroplasty, knee arthroplasty, and vascular surgery. It deserves consideration as a more effective approach to target chart reviews for identifying SSIs.

Initial Antibiotic Selection and Patient Outcomes: Observations from the National Pneumonia Project

BACKGROUND Guidelines for empirical treatment of hospitalized patients with pneumonia provide specific recommendations for antibiotic selection that are primarily based on findings from observational studies. METHODS We conducted a retrospective study of 27,330 community-dwelling, immunocompetent Medicare patients (age, >65 years) with pneumonia who were hospitalized in 1998-1999 and 2000-2001. Associations between initial antimicrobial regimens and risk-adjusted mortality were assessed, accounting for differences in patient characteristics, comorbidities, illness severity, geographic location, and processes of care. Treatment with nonpseudomonal third-generation cephalosporin monotherapy constituted the reference group for comparisons. RESULTS For patients not in the intensive care unit, initial treatment with fluoroquinolone monotherapy was associated with reduced in-hospital mortality, 14-day mortality, and 30-day mortality rates (adjusted odds ratio [AOR] for 30-day mortality, 0.7; 95% confidence interval [CI], 0.6-0.9; P = .001). The combination of a cephalosporin plus a macrolide was associated with reduced 14-day and 30-day mortality rates (AOR for 30-day mortality, 0.7; 95% CI, 0.6-0.9; P < .001). For intensive care unit patients, the combination of a cephalosporin and a macrolide was associated with reduced in-hospital mortality (AOR, 0.6; 95% CI, 0.3-0.9; P = .018). CONCLUSIONS Initial antimicrobial treatment with the combination of a second- or third-generation cephalosporin and a macrolide or initial treatment with a fluoroquinolone was associated with a reduced 30-day mortality rate, compared with treatment with third-generation cephalosporin monotherapy, among non-intensive care unit patients. Although our results are consistent with other observational studies, controversy continues to exist about the use of nonexperimental cohort studies to demonstrate associations between processes of care, such as antibiotic selection, and patient outcomes.

Use of Medicare Claims to Rank Hospitals by Surgical Site Infection Risk following Coronary Artery Bypass Graft Surgery

OBJECTIVE To evaluate whether longitudinal insurer claims data allow reliable identification of elevated hospital surgical site infection (SSI) rates. DESIGN We conducted a retrospective cohort study of Medicare beneficiaries who underwent coronary artery bypass grafting (CABG) in US hospitals performing at least 80 procedures in 2005. Hospitals were assigned to deciles by using case mix-adjusted probabilities of having an SSI-related inpatient or outpatient claim code within 60 days of surgery. We then reviewed medical records of randomly selected patients to assess whether chart-confirmed SSI risk was higher in hospitals in the worst deciles compared with the best deciles. PARTICIPANTS Fee-for-service Medicare beneficiaries who underwent CABG in these hospitals in 2005. RESULTS We evaluated 114,673 patients who underwent CABG in 671 hospitals. In the best decile, 7.8% (958/12,307) of patients had an SSI-related code, compared with 24.8% (2,747/11,068) in the worst decile ([Formula: see text]). Medical record review confirmed SSI in 40% (388/980) of those with SSI-related codes. In the best decile, the chart-confirmed annual SSI rate was 3.2%, compared with 9.4% in the worst decile, with an adjusted odds ratio of SSI of 2.7 (confidence interval, 2.2-3.3; [Formula: see text]) for CABG performed in a worst-decile hospital compared with a best-decile hospital. CONCLUSIONS Claims data can identify groups of hospitals with unusually high or low post-CABG SSI rates. Assessment of claims is more reproducible and efficient than current surveillance methods. This example of secondary use of routinely recorded electronic health information to assess quality of care can identify hospitals that may benefit from prevention programs.

Activity of Commonly Used Antimicrobial Prophylaxis Regimens against Pathogens Causing Coronary Artery Bypass Graft and Arthroplasty Surgical Site Infections in the United States, 2006–2009

BACKGROUND Coronary artery bypass graft (CABG) and primary arthroplasty surgical site infection (SSI) rates are declining slower than other healthcare-associated infection rates. We examined antimicrobial prophylaxis (AMP) regimens used for these operations and compared their spectrum of activity against reported SSI pathogens. METHODS Pathogen distributions of CABG and hip/knee arthroplasty complex SSIs (deep and organ/space) reported to the National Healthcare Safety Network (NHSN) from 2006 through 2009 and AMP regimens (same procedures and time period) reported to the Surgical Care Improvement Project (SCIP) were analyzed. Regimens were categorized as standard (cefazolin or cefuroxime), β-lactam allergy (vancomycin or clindamycin with or without an aminoglycoside), and extended spectrum (vancomycin and/or an aminoglycoside with cefazolin or cefuroxime). AMP activity of each regimen was predicted on the basis of pathogen susceptibility reports and published spectra of antimicrobial activity. RESULTS There were 6,263 CABG and arthroplasty complex SSIs reported (680,489 procedures; 880 NHSN hospitals). Among 6,574 pathogens reported, methicillin-sensitive Staphylococcus aureus (23%), methicillin-resistant S. aureus (18%), coagulase-negative staphylococci (17%), and Enterococcus species (7%) were most common. AMP regimens for 2,435,703 CABG and arthroplasty procedures from 3,330 SCIP hospitals were analyzed. The proportion of pathogens predictably susceptible to standard (used in 75% of procedures), β-lactam (12%), and extended-spectrum (8%) regimens was 41%-45%, 47%-96%, and 81%-96%, respectively. CONCLUSION Standard AMP, used in three-quarters of CABG and primary arthroplasty procedures, has inadequate activity against more than half of SSI pathogens reported. Alternative strategies may be needed to prevent SSIs caused by pathogens resistant to standard AMP regimens.

Use of Medicare claims to identify US hospitals with a high rate of surgical site infection after hip arthroplasty.

OBJECTIVE To assess the ability of Medicare claims to identify US hospitals with high rates of surgical site infection (SSI) after hip arthroplasty. DESIGN Retrospective cohort study. SETTING Acute care US hospitals. PARTICIPANTS Fee-for-service Medicare patients 65 years of age and older who underwent hip arthroplasty in US hospitals from 2005 through 2007. METHODS Hospital rankings were derived from claims codes suggestive of SSI, adjusted for age, sex, and comorbidities, while using generalized linear mixed models to account for hospital volume. Medical records were obtained for validation of infection on a random sample of patients from hospitals ranked in the best and worst deciles of performance. We then calculated the risk-adjusted odds of developing a chart-confirmed SSI after hip arthroplasty in hospitals ranked by claims into worst- versus best-performing deciles. RESULTS Among 524,892 eligible Medicare patients who underwent hip arthroplasty at 3,296 US hospitals, a patient who underwent surgery in a hospital ranked in the worst-performing decile based on claims-based evidence of SSI had 2.9-fold higher odds of developing a chart-confirmed SSI relative to a patient with the same age, sex, and comorbidities in a hospital ranked in the best-performing decile (95% confidence interval, 2.2-3.7). CONCLUSIONS Medicare claims successfully distinguished between hospitals with high and low SSI rates following hip arthroplasty. These claims can identify potential outlier hospitals that merit further evaluation. This strategy can also be used to validate the completeness of public reporting of SSI.

Quality and Equity of Care in U.S. Hospitals

BACKGROUND Nearly every U.S. hospital publicly reports its performance on quality measures for patients who are hospitalized for acute myocardial infarction, heart failure, or pneumonia. Because performance rates are not reported according to race or ethnic group, it is unclear whether improvements in equity of care have accompanied aggregate improvements in health care quality over time. METHODS We assessed performance rates for quality measures covering three conditions (six measures for acute myocardial infarction, four for heart failure, and seven for pneumonia). These rates, adjusted for patient- and hospital-level covariates, were compared among non-Hispanic white, non-Hispanic black, and Hispanic patients who received care between 2005 and 2010 in acute care hospitals throughout the United States. RESULTS Adjusted performance rates for the 17 quality measures improved by 3.4 to 57.6 percentage points between 2005 and 2010 for white, black, and Hispanic adults (P<0.001 for all comparisons). In 2005, as compared with adjusted performance rates for white patients, adjusted performance rates were more than 5 percentage points lower for black patients on 3 measures (range of differences, 12.3 to 14.2) and for Hispanic patients on 6 measures (5.6 to 14.5). Gaps decreased significantly on all 9 of these measures between 2005 and 2010, with adjusted changes for differences between white patients and black patients ranging from -8.5 to -11.8 percentage points and from -6.2 to -15.1 percentage points for differences between white patients and Hispanic patients. Decreasing differences according to race or ethnic group were attributable to more equitable care for white patients and minority patients treated in the same hospital, as well as to greater performance improvements among hospitals that disproportionately serve minority patients. CONCLUSIONS Improved performance on quality measures for white, black, and Hispanic adults hospitalized for acute myocardial infarction, heart failure, or pneumonia was accompanied by increased racial and ethnic equity in performance rates both within and among U.S. hospitals. (Funded by the Centers for Medicare and Medicaid Services and the Veterans Affairs Health Services Research and Development Career Development Program.).

Harnessing claims to improve detection of surgical site infections following hysterectomy and colorectal surgery.

Surgical site infection (SSI) surveillance is performed using a variety of methods with unclear performance characteristics. We used claims data to identify records for review following hysterectomy and colorectal surgery. Claims-enhanced screening identified SSIs missed by routine surveillance and could be used for targeted chart review to improve SSI detection.

Medicare claims can be used to identify US hospitals with higher rates of surgical site infection following vascular surgery.

Background:Surgical site infections (SSIs) following vascular surgery have high morbidity and costs, and are increasingly tracked as hospital quality measures. Objective:To assess the ability of Medicare claims to identify US hospitals with high SSI rates after vascular surgery. Research Design:Using claims from fee-for-service Medicare enrollees of age 65 years and older who underwent vascular surgery from 2005 to 2008, we derived hospital rankings using previously validated codes suggestive of SSI, with individual-level adjustment for age, sex, and comorbidities. We then obtained medical records for validation of SSI from hospitals ranked in the best and worst deciles of performance, and used logistic regression to calculate the risk-adjusted odds of developing an SSI in worst-decile versus best-decile hospitals. Results:Among 203,023 Medicare patients who underwent vascular surgery at 2512 US hospitals, a patient undergoing surgery in a hospital ranked in the worst-performing decile based on claims had 2.5 times higher odds of developing a chart-confirmed SSI relative to a patient with the same age, sex, and comorbidities in a hospital ranked in the best-performing decile (95% confidence interval, 2.0–3.1). SSI confirmation among patients with claims suggesting infection was similar across deciles, and we found similar findings in analyses limited to deep and organ/space SSIs. We report on diagnosis codes with high sensitivity for identifying deep and organ/space SSI, with one-to-one mapping to ICD-10-CM codes. Conclusions:Claims-based surveillance offers a standardized and objective methodology that can be used to improve SSI surveillance and to validate hospitals’ publicly reported data.