Examining the relationship between processes of care and selected AHRQ patient safety indicators postoperative wound dehiscence and accidental puncture or laceration using the VA electronic medical record

This study examines whether Agency for Healthcare Research and Quality Patient Safety Indicators (PSIs) Postoperative Wound Dehiscence (PWD) and Accidental Puncture or Laceration (APL) events reflect problems with hospital processes of care (POC). The authors randomly selected 112 PSI-flagged PWD/APL discharges from 2002-2007 VA administrative data, identified true cases using chart review, and matched cases with controls. This yielded a total of 95 case-control pairs per PSI. Patient information and clinical processes on each case-control pair were abstracted from the electronic medical record (EMR). Although PWD cases and controls differed on incision and closure types, APL cases and controls were comparable in examined processes. Further exploration of the process differences between PWD cases and controls indicated that they were primarily caused by patients' underlying surgical problems rather than quality of care shortfalls. Documentation of POC was frequently missing in EMRs. Future studies should combine EMR review with alternative approaches, such as direct observation, to better assess POC.

Quality measurement and improvement in general surgery

Increasing emphasis is being placed on health care quality measurement and improvement in the US. Within general surgery, several sophisticated quality-measurement and outcomes systems have been developed. These include the National Surgical Quality Improvement Program, the use of selective referral and centers of excellence, the Surgical Care Improvement Project, and the World Health Organization Surgical Safety Checklist. This article reviews each of these quality-improvement initiatives, highlights their relative contributions, and discusses future directions of quality improvement within general surgery.

Is development of postoperative venous thromboembolism related to thromboprophylaxis use? A case-control study in the Veterans Health Administration

BACKGROUND

Observational studies continue to report thromboprophylaxis underuse for postoperative pulmonary embolism/deep vein thrombosis (pPE/DVT) despite the long-standing existence of prevention guidelines. However, data are limited on whether thromboprophylaxis use differs between patients developing pPE/DVT versus those who do not or on why prophylaxis is withheld.

METHODS

Administrative data (2002-2007) from 28 Veterans Health Administration hospitals were screened for discharges with (1) pPE/DVT as flagged by the Agency for Healthcare Research and Quality (AHRQ) Patient Safety Indicator software and (2) pharmacoprophylaxis-recommended procedures, and the medical records were reviewed to ascertain true pPE/DVT cases. Controls were selected by matching cases by hospital, age, sex, diagnosis-related group, and predicted probability for developing pPE/DVT, and who underwent a pharmacoprophylaxis-recommended procedure. Records were assessed for "appropriate pharmacoprophylaxis use," defined primarily per American College of Chest Physicians (ACCP) guidelines, and reasons for anticoagulant nonuse.

RESULTS

The 116 case-control pairs were similar in terms of demographics, surgery type, ACCP risk category, and appropriate pharmacoprophylaxis rates overall. Of the highest-risk patients, respective pharmacoprophylaxis rates among cases and controls were 88% versus 92% among hip/knee replacements and 31% versus 48% among cancer patients. Of the cases and controls who did not receive appropriate pharmacoprophylaxis, only about 25% had documented contraindications. Reviewers identified contraindications in 14% of cases and 9% of controls.

CONCLUSIONS

Similarities in preventive pPE/DVT practice between cases and controls suggest that pPE/DVTs occur despite implementation of guideline-adherent practices.

Recurrence of mitral regurgitation after partial versus complete mitral valve ring annuloplasty for functional mitral regurgitation

OBJECTIVES

Both partial and complete annuloplasty rings are used for mitral valve repair for patients with functional mitral regurgitation (FMR). We sought to determine if recurrence of mitral regurgitation (MR) is affected by the type of ring used.

METHODS

Five hundred forty-eight patients diagnosed with FMR underwent mitral valve repair with ring annuloplasty between 1998 and 2008 in our institution. Medical records were reviewed retrospectively for clinical and echocardiographic data to determine the presence of recurrent MR (defined as moderate or severe).

RESULTS

Among 479 patients for whom postoperative echocardiographic data were available, recurrent MR occurred less frequently in the complete versus partial ring group (20 of 209 [10%] vs 56 of 270 [21%] patients; P = .001), despite lower preoperative ejection fractions in the complete ring group (median, 35%; interquartile range, 25%-45% vs median, 40%; interquartile range, 30%-55%; P < .001). Kaplan-Meier analysis demonstrated greater freedom from recurrent MR in the complete ring group (108 vs 103 months; P = .001). Risk-matched propensity analysis of 102 patients per group (area under the curve, 0.824; 95% confidence interval, 0.788-0.861; P < .001) also demonstrated that complete ring recipients had greater freedom from recurrent MR than partial ring recipients by univariate analysis (7 [7%] vs 17 [17%] patients; P = .049), and a trend toward greater freedom by Kaplan-Meier analysis (110 vs 104 months; P = .068).

CONCLUSIONS

The use of complete mitral annuloplasty rings provides improved freedom from recurrent MR in patients with FMR.

Ventral hernia repair with synthetic, composite, and biologic mesh: characteristics, indications, and infection profile

BACKGROUND

A variety of mesh materials are available for ventral hernia repair (VHR), each with a unique set of characteristics. Surgeons are offered an ever-expanding selection of products, making a review of the available materials timely.

METHODS

Current surgical literature is reviewed to describe the different types of synthetic mesh, the indications for the use of each type, their relative risks of infection, and other benefits and shortcomings. We also review clinical studies demonstrating outcomes, efficacy, and use of the meshes in different surgical settings, including laparoscopic hernia repair and special situations such as infection or large abdominal wall defects.

RESULTS

Three main types of prosthetic mesh are available. Synthetic mesh, such as polypropylene (PP) or polyester, is characterized by high tensile strength and vigorous tissue ingrowth, but is unsuitable for intra-abdominal placement because of its tendency to induce bowel adhesions. Composite, or barrier-coated, mesh is a dual-sided prosthetic having a synthetic parietal side to promote a strong repair and a visceral surface that repels tissue ingrowth and decreases adhesion formation. Biologic mesh is a collagen-based human, porcine, or bovine scaffold that may be implanted in the extra- or intra-peritoneal position. Biologic mesh is used frequently in the setting of infected or contaminated surgical incisions.

CONCLUSIONS

Synthetic PP mesh is an appropriate, durable material for extra-peritoneal placement in uncomplicated, clean VHR. Expanded polytetrafluoroethylene and composite meshes are suitable for intraperitoneal placement during laparoscopic VHR. Biologic meshes may be appropriate for contaminated fields or other special situations, but there is no consensus on when or how to use them.

Aortic valve endocarditis from Staphylococcus lugdunensis

This is a case of aortic valve endocarditis and leaflet perforation caused by Staphylococcus lugdunensis successfully treated with aortic valve replacement and antibiotics. We believe that the patient's endocarditis may be related to the vasectomy he underwent two months prior to presentation, as S. lugdunensis is an integral component of normal skin flora of the lower abdomen and groin. We also suggest that whenever this organism is found in patients with endocarditis, early surgical treatment of the infected valve should be considered, as S. lugdunensis is an aggressive and virulent coagulase-negative staphylococcus.

How valid is the AHRQ Patient Safety Indicator "postoperative physiologic and metabolic derangement"?

BACKGROUND

The Agency for Healthcare Research and Quality Patient Safety Indicator postoperative physiologic and metabolic derangement (PMD) uses ICD-9-CM codes to screen for potentially preventable acute kidney injury (AKI) requiring dialysis plus diabetes-related complications after elective surgery. Data on PMD's accuracy in identifying true events are limited. We examined the indicator's positive predictive value (PPV) in the Veterans Health Administration (VA).

STUDY DESIGN

Trained abstractors reviewed medical records of 119 PSI software-flagged PMD cases. We calculated PPVs overall and separately for renal- and diabetes-related complications. We also examined false positives to determine reasons for incorrect identification, and true positives to determine PMD-related outcomes and risk factors.

RESULTS

Overall 75 cases were true positives (PPV 63%, 95% CI 54% to 72%); 73 of 104 AKI cases were true positives (PPV 70%, 60% to 79%); only 2 of 15 diabetes cases were true positives (PPV 13%, 2% to 40%). Of all false positives, 70% represented nonelective admissions and 23% had the complication present on admission. Of AKI true positives, 37% died and 26% were discharged on dialysis; 55% had chronic kidney disease (≥ stage 3) present on admission. Cardiac surgery represented the largest category of AKI-associated index procedures (30%). AKI was most commonly attributed to perioperative renal hypoperfusion (84% of true positives), followed by nephrotoxins (33%) including contrast (11%).

CONCLUSIONS

Due to its low PPV, we recommend removing diabetes complications from the indicator and focusing on AKI. PMD's PPV could be significantly improved by using present-on-admission codes, and specific to the VA, by introduction of admission status codes. Many PMD-identified cases appeared to be at high risk based on patient- and procedure-related factors. The degree to which such cases are truly preventable events requires further assessment.

Positive predictive value of the AHRQ Patient Safety Indicator "Postoperative Sepsis": implications for practice and policy

BACKGROUND

Patient Safety Indicator (PSI) 13, or "Postoperative Sepsis," of the Agency for Healthcare Quality and Research (AHRQ), was recently adopted as part of a composite measure of patient safety by the Centers for Medicare and Medicaid Services (CMS). We sought to examine its positive predictive value (PPV) by determining how well it identifies true cases of postoperative sepsis.

STUDY DESIGN

Two retrospective cross-sectional studies of hospitalization records that met PSI 13 criteria were conducted, one within the Veterans Administration (VA) Hospitals from fiscal years (FY) 2003 to 2007, and one within community hospitals between October 1, 2005 and March 31, 2007. Trained abstractors reviewed medical records from each database using standardized abstraction instruments. We determined the PPV of the indicator and performed descriptive analyses of cases.

RESULTS

Of 112 cases flagged and reviewed within the VA system, 59 were true events of postoperative sepsis, yielding a PPV of 53% (95% CI 42% to 64%). Within the community hospital sector, of 164 flagged and reviewed cases, 67 were true cases of postoperative sepsis, yielding a PPV of 41% (95% CI 28% to 54%). False positives were due to infections that were present on admission, urgent or emergent cases, no clinical diagnosis of sepsis, or other coding limitations such as nonspecific shock in postoperative patients.

CONCLUSIONS

PSI 13 has relatively poor predictive ability to identify true cases of postoperative sepsis in both the VA and nonfederal sectors. The lack of information on diagnosis timing, confusion about the definition of elective admission, and coding limitations were the major reasons for false positives. As it currently stands, the use of PSI 13 as a stand-alone measure for hospital reporting appears premature.

Acute Infectious Pseudoaneurysm of the Descending Thoracic Aorta and Review of Infectious Aortitis

Thoracic aortic wall disruptions may occur secondary to trauma, surgical interventions, infection, or autoimmune or idiopathic inflammatory disorders. Such vessel wall disruption can lead to aortic dissections, aneurysm development, or more commonly, pseudoaneurysm (PSA) formation. Although aortic wall infections as an antecedent to mycotic aneurysms have been recognized since the 17th century, there has been a temporal evolution in the development of this disease. Prior to the antibiotic era they were commonly associated with endocarditis or syphilis. More recently, however, they are associated with infection of a damaged atherosclerotic area of the aorta and secondary hematogenous or contiguous seeding. We report the first case of the rapid development of a pseudoaneurysm in the descending thoracic aorta attributable to an infection of a contiguous esophageal duplication cyst by a diagnostic esophageal ultrasound (EUS) fine-needle aspiration. A literature review of mycotic thoracic aortic aneurysms and pseudoaneurysms is also presented.

Clinical images. Classic presentation of a type II obturator hernia

A type II obturator hernia is a rare clinical entity that may be found on imaging and at surgery, as seen in this case of a 91-year-old woman who presented to our emergency department. Images are presented with treatment choices and a brief discussion on different types of obturator hernias.

Positive predictive value of computerized records for major congenital malformations

PURPOSE

To assess the positive predictive value of computerized records in a linked database of vital records and infant claims, with medical record confirmation to detect congenital malformations in a Medicaid population.

METHODS

Study subjects were selected from cases identified for three studies of congenital malformations in the Tennessee Medicaid (TennCare) population including 173 827 (studies 1 and 2) and 519 465 (study 3) mother/infant pairs. Possible malformations were identified from computerized databases of birth certificates linked with maternal and infant claims. Medical records were reviewed for all possible congenital malformations and positive predictive values were calculated for each data source and for each malformation.

RESULTS

Among 1430 potential congenital malformations identified from either birth certificates or inpatient claims, 67.7% were confirmed by medical record review. The positive predictive value varied considerably depending on the data source and the organ system. For example, cardiac defects had a very low positive predictive value when identified from birth certificates, and somewhat higher positive predictive value when identified from inpatient claims. Orofacial defects had 90.9% positive predictive value from birth certificates and inpatient claims. Requiring evidence of a diagnostic or therapeutic procedure increased the positive predictive value to >90% for specific defects, but substantially reduced the number of included cases.

CONCLUSIONS

Depending on the defect, computerized claims data linked to vital records offer opportunities for identifying birth defects in populations of vulnerable persons. However, for many defects, medical record confirmation is likely to be required to provide valid identification of malformation occurrence.

A decade of direct-to-consumer advertising of prescription drugs

BACKGROUND

Evidence suggests that direct-to-consumer advertising of prescription drugs increases pharmaceutical sales and both helps to avert underuse of medicines and leads to potential overuse. Concern about such advertising has increased recently owing to the withdrawal from the market of heavily advertised drugs found to carry serious risks. Moreover, the Food and Drug Administration (FDA) has been criticized for its weak enforcement of laws regulating such advertising.

METHODS

We examined industry-wide trends in spending by pharmaceutical companies on direct-to-consumer advertising and promotion to physicians during the past decade. We characterized the drugs for which such advertising is used and assessed the timing of advertising after a drug is introduced. Finally, we examined trends in the FDA's regulation of drug advertising.

RESULTS

Total spending on pharmaceutical promotion grew from $11.4 billion in 1996 to $29.9 billion in 2005. Although during that time spending on direct-to-consumer advertising increased by 330%, it made up only 14% of total promotional expenditures in 2005. Direct-to-consumer campaigns generally begin within a year after the approval of a product by the FDA. In the context of regulatory changes requiring legal review before issuing letters, the number of letters sent by the FDA to pharmaceutical manufacturers regarding violations of drug-advertising regulations fell from 142 in 1997 to only 21 in 2006.

CONCLUSIONS

Spending on direct-to-consumer advertising has continued to increase in recent years in spite of the criticisms leveled against it. Our findings suggest that calls for a moratorium on such advertising for new drugs would represent a dramatic departure from current practices.

Involvement of XRCC1 and DNA ligase III gene products in DNA base excision repair

DNA ligase III and the essential protein XRCC1 are present at greatly reduced levels in the xrcc1 mutant CHO cell line EM-C11. Cell-free extracts prepared from these cells were used to examine the role of the XRCC1 gene product in DNA base excision repair in vitro. EM-C11 cell extract was partially defective in ligation of base excision repair patches, in comparison to wild type CHO-9 extracts. Of the two branches of the base excision repair pathway, only the single nucleotide insertion pathway was affected; no ligation defect was observed in the proliferating cell nuclear antigen-dependent pathway. Full complementation of the ligation defect in EM-C11 extracts was achieved by addition to the repair reaction of recombinant human DNA ligase III but not by XRCC1. This is consistent with the notion that XRCC1 acts as an important stabilizing factor of DNA ligase III. These data demonstrate for the first time that xrcc1 mutant cells are partially defective in ligation of base excision repair patches and that the defect is specific to the polymerase beta-dependent single nucleotide insertion pathway.