The actual role of CT and ventilation-perfusion scanning in workup for suspected pulmonary embolism: evidence from hospitals.

OBJECTIVE: Over the past two decades, CT has been found valuable in the diagnosis of pulmonary embolism (PE). We sought to ascertain the relative roles of CT and ventilation-perfusion (V/Q) scanning, the previously preferred technique, in the diagnosis of PE in recent practice and whether there is variation among hospital types. MATERIALS AND METHODS: Using the Medicare anonymized 5% of beneficiaries complete claims file for 2005, we studied the use of relevant CT and V/Q scanning in the evaluation of patients with a diagnosis of PE and of patients with symptoms that might have been due to PE (chest pain, syncope, difficulty breathing). In 2008, we surveyed the radiology departments of Pennsylvania hospitals about the use of CT and V/Q scanning for PE, service availability hours, and what equipment was used. RESULTS: In all data, we found that CT was used approximately six times as frequently as V/Q scanning. In the Medicare data, only small differences in frequency of use of CT and V/Q scanning were associated with hospital characteristics. Academic hospitals did not differ in a major way from other hospitals, nor did small or rural hospitals. In the survey, 97% of radiology departments reported that CT was available for evaluation of PE 24 hours a day 7 days a week. Ninety-three percent of departments reported V/Q scanning was available at some times; 77% reported V/Q available at all times. CONCLUSION: CT was a fully disseminated and dominant technique for the diagnosis of PE by 2005, and it was readily available at small and rural hospitals. The lack of availability of off-hours V/Q scanning at a substantial fraction of hospitals may be a problem for patients with contraindications to CT.

Provider Volume of Total Knee Arthroplasties and Patient Outcomes in the HCUP-Nationwide Inpatient Sample.

BACKGROUND: The relationship between volume and outcome of total knee arthroplasties has never been evaluated in a nationally representative sample, to our knowledge. We hypothesized that surgeons and hospitals with higher patient volumes would have better outcomes, as defined by lower mortality rates, shorter hospital stays, and lower postoperative complication rates. METHODS: The 1997 Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample, Release 6, provided discharge abstracts of patients undergoing total knee arthroplasty from a national stratified probability sample. Logistic and multiple regression models were used to estimate the adjusted association of surgeon or hospital volume with rates of in-hospital mortality, pulmonary thromboembolism, deep venous thrombosis in the lower extremity, and postoperative wound infection as well as length of hospital stay. Estimates were calculated for a target population of 277,550 patients. Models were adjusted for comorbidity, age, gender, race, household income, and procedure (primary or revision arthroplasty). RESULTS: The patients were mostly white (70.2%) and female (62.7%), with a mean age of 68.9 years. The overall in-hospital mortality rate for the target population was 0.2%, and the average length of stay was 4.6 days for the primary total knee arthroplasties and 4.9 days for the revision procedures. Surgeon volumes of at least fifteen procedures per year and hospital volumes of at least eighty-five per year were significantly and linearly associated with lower mortality rates (odds ratio = 0.56 [0.24 to 1.31] for surgeon volume of > or = 60). No other association demonstrated a significant and directionally consistent linear trend for improved outcomes. CONCLUSION: Patients treated by providers with lower caseload volumes had higher rates of mortality following total knee arthroplasty in 1997. Proposing volume standards could decrease patient mortality following this procedure.