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Michael A Bettmann

Publications and source records attributed to Michael A Bettmann.

17 recordsLinked to original sources
PubMed2006

Operating expenses for the diagnosis and treatment of peripheral vascular disease in an academic interventional radiology department: cost calculations according to a microeconomic method.

PURPOSE: A correct understanding of the true costs of a procedure is necessary to make informed decisions in cost-effectiveness analyses. The actual comprehensive costs of performing cardiovascular and interventional radiology (CVIR) procedures were analyzed in the present study, as opposed to charges or ratios of costs to charges (RCCs), as often used in the literature. MATERIALS AND METHODS: Costs included labor, equipment, administration, facility establishment and maintenance, overhead, and consumable supplies. Cost identification was initially performed with use of an hourly rate that reflected the cost of operating the CVIR section. This was then combined with the costs of the consumable supplies used during each type of procedure. Eight types of vascular procedures were studied in 235 consecutive patients to determine mean procedure duration and supplies consumption. Costs were then compared with charges and RCCs of these procedures. RESULTS: The hourly rate for operating one angiography suite was 690 dollars. Average cost by procedure, including hourly rate plus consumable supplies, were: aortic arteriogram, 1,442 dollars; aortobifemoral arteriogram, 1,554 dollars; unilateral limb arteriogram, 1,307 dollars; simple iliac or femoropopliteal angioplasty, 2,119 dollars; arterial stent placement, 2,780 dollars; percutaneous thrombectomy, 1,998 dollars; arterial in situ thrombolysis, 3,133 dollars; and arteriogram after thrombolysis, 926 dollars. RCCs calculated for each procedure ranged from 0.39 (thrombectomy) to 1.92 (control arteriography during or after thrombolysis) and were lower than expected based on previous reports. CONCLUSIONS: The average actual costs of several common diagnostic and therapeutic procedures for peripheral vascular occlusive disease were established, allowing determination of the relative importance of different cost components. This methodology may serve as a template for future cost analyses.

Academic Medical Centers↗
PubMed2006

Günther Tulip filter retrievability multicenter study including CT follow-up: final report.

PURPOSE: To evaluate the safety and effectiveness of retrieval of the Günther Tulip inferior vena cava (IVC) filter. MATERIALS AND METHODS: This was a nonrandomized, single-armed, multicenter prospective investigation. Patients at temporary high risk for pulmonary embolism (PE) or deep vein thrombosis (DVT) who did not require a permanent filter were eligible. Forty-one patients received 42 Günther Tulip filters: 22 men and 19 women with a mean age of 47.7 years. Indications for filter placement included prophylaxis, PE, and DVT. Three months after filter retrieval, contrast agent-enhanced computed tomography of the abdomen, jugular vein ultrasonography, and clinical follow-up were performed. RESULTS: The filter retrieval rate was 57% (23 of 41). Günther Tulip filters were removed at a mean of 11.1 days (range, 2-14 d). The technical and clinical success rates for filter retrieval were both 100%. One placement complication and two protocol deviations occurred. These patients were excluded in terms of retrieval-related outcomes. One case of PE occurred with a filter in place, and one filter migrated to the heart. There were no acute complications caused by filter retrieval. At 3-month follow-up, there was no recurrent PE, DVT, jugular vein occlusion, or IVC stenosis or occlusion. CONCLUSION: In this multicenter study, retrieval of the Günther Tulip filter was safe and without recurrent thromboembolic events or evidence of IVC or jugular vein damage at 3-month follow-up.

Adult↗
PubMed2005

Docetaxel/Gemcitabine followed by gemcitabine and external beam radiotherapy in patients with pancreatic adenocarcinoma.

BACKGROUND: Pancreatic cancer remains highly lethal. Previous attempts with neoadjuvant therapy in this disease have been inconclusive, but a potential for benefit exists. We conducted a phase II trial of dose-intense docetaxel and gemcitabine followed by twice-weekly gemcitabine and external beam radiotherapy in patients with pancreatic adenocarcinoma. METHODS: Patients with stage I to III disease were eligible. Docetaxel 65 mg/m(2) intravenously over 1 hour and gemcitabine 4000 mg/m(2) given intravenously over 30 minutes were given on days 1, 15, and 29. On day 43, radiotherapy was begun at 50.4 Gy with gemcitabine 50 mg/m(2) intravenously over 30 minutes twice weekly for 12 doses. After treatment, patients were considered for resection. RESULTS: Twenty-four assessable patients were recruited onto the trial. All but one patient completed a full 12 weeks of therapy. Grade 3 and 4 hematological and nonhematological toxicities were common but manageable, and neutropenic fever did not occur. No patient had local tumor progression. Twelve patients (50%) responded by Response Evaluation Criteria in Solid Tumors Group (RECIST) criteria, including one radiographic complete response. Seventeen patients underwent resection after therapy. Margin-negative resections were performed in 13 patients, including 9 patients whose disease was borderline or unresectable before treatment. A treatment effect was seen in all resection specimens. There have been no local recurrences of tumor, and several patients remain alive without evidence of disease. CONCLUSIONS: Docetaxel/gemcitabine followed by gemcitabine/radiotherapy is active in the treatment of pancreatic adenocarcinoma, with manageable toxicity. Tumor downstaging occurs in some patients to allow complete resection. Further investigation of this regimen is warranted.

Adenocarcinoma↗
PubMed2005

Percutaneous radiologic gastrostomy versus percutaneous endoscopic gastrostomy: a comparison of indications, complications and outcomes in 370 patients.

OBJECTIVE: Percutaneous access to the stomach can be achieved by endoscopic or fluoroscopic methods. Our objective was to compare indications, complications, efficacy and outcomes of these two techniques. METHODS: Records of 370 patients with feeding tubes placed either endoscopically by gastroenterology, or fluoroscopically by radiology, at our university-based tertiary care center over a 54-month period were reviewed. RESULTS: 177 gastrostomies were placed endoscopically and 193 fluoroscopically. Nutrition was the most common indication in each group (94 and 92%), but the most common underlying diagnosis was neurologic impairment in the endoscopic group (n=89, 50%) and malignancy in the fluoroscopic group (n=134, 69%) (p<0.001). Complications in the first 30 days were more common with fluoroscopic placement (23% versus 11%, p=0.002), with infection most frequent. Correlates of late complications were inpatient status (OR 0.26, 95%CI: 0.13-0.51) and a diagnosis of malignancy (OR 2.2, 95%CI: 1.03-4.84). Average follow-up time was 108 days in the fluoroscopic group and 174 days in the endoscopic group. CONCLUSIONS: Both endoscopic and fluoroscopic gastrostomy tube placement are safe and effective. Outpatient status was associated with greater early and late complication rates; minor complications such as infection were greater in the fluoroscopic group, while malignancy was associated with late complications.

Aged↗
PubMed2004

Clinicians' perceptions of the value of ventilation-perfusion scans.

RATIONALE: The goal of this investigation was to understand clinicians' perceptions of the probability of pulmonary embolism as a function of V/Q scan results of normal, low, intermediate, and high probability. METHODS: A questionnaire was developed and distributed to 429 clinicians at a single academic medical center. The response rate was 44% (188 of 429). The questions included level of training, specialty, probability of PE given 1 of the 4 V/Q scan results, and estimations of the charges for V/Q scanning and pulmonary angiography, and estimations of the risks of pulmonary angiography. RESULTS: The medians and ranges for the probability of pulmonary embolism given a normal, low, intermediate, and high probability V/Q scan result were 2.5% (0-30), 12.5% (0.5-52.5), 41.25% (5-75), and 85% (5-100), respectively. Eleven percent (21 of 188) of the respondents listed the probability of PE in patients with a low probability V/Q scan as being 5% or less, and 33% (62 of 188) listed the probability of PE given an intermediate probability scan as 50% or greater. The majority correctly identified the rate of serious complications of pulmonary arteriography, but many respondents underestimated the charge for V/Q scans and pulmonary arteriography. CONCLUSIONS: A substantial minority of clinicians do not understand the probability of pulmonary embolism in patients with low and intermediate probability ventilation-perfusion scans. More quantitative reporting of results is recommended. This could be particularly important because VQ scans are used less frequently but are still needed in certain clinical situations.

Angiography↗
PubMed2004

Retrospective assessment of risk factors to predict tunneled hemodialysis catheter outcome.

PURPOSE: To identify factors that may influence the function, outcome, and complications associated with tunneled hemodialysis catheters. MATERIALS AND METHODS: Radiology reports and hemodialysis, medical, and Clinical Information System (computerized patient medical record system) records were retrospectively reviewed in 221 consecutive patients who underwent tunneled hemodialysis catheter placement by interventional radiologists between January 11, 1996 and January 13, 2000 at Dartmouth-Hitchcock Medical Center. Various patient characteristics (diabetes, smoking, hypertension, age, sex, atherosclerotic cardiovascular disease, history of cardiac catheterization, coumadin use, functional status, and obesity) were assessed for their relationship to the outcome of hemodialysis catheters. Catheter outcome was examined by calculating infection rate, thrombosis rate, fibrin formation rate, mechanical malfunction rate, and total complication rate. With these patient characteristics and outcome variables, multiple regression analysis was performed with STATA (College Station, TX) statistical analysis software. RESULTS: Of the 221 patients reviewed, 39 patients were lost to follow-up. Among the remaining 182 patients, 427 catheters were placed for a total number of 36994 catheter-days. For overall complication rate, multiple regression analysis revealed a statistically significant positive correlation only for hypertension (P =.032). Total complication rate was 0.76 events per 100 catheter-days (95% CI: 0.53-1.00) for patients with a documented history of hypertension and 0.27 events per 100 catheter-days (95% CI: 0.08-0.45) for patients without (P =.024, paired student t test). For patients with diabetes versus patients without, the infection rates were 0.34 episodes per 100 catheter-days (95% CI: 0.15-0.53) and 0.12 episodes per 100 catheter-days (95% CI: 0.06-0.18), respectively, (P =.011, paired student t test). Thrombosis rate for patients on coumadin was 0.13 events per 100 catheter-days (95% CI: -0.14-0.40), while thrombosis rate for patients not taking coumadin was 0.03 events per 100 catheter-days (95% CI: 0-0.05) (P =.036, paired student t test). CONCLUSION: Hypertension is a risk factor for poor outcome of tunneled hemodialysis catheters as measured by total complication rate requiring catheter removal or exchange. In this retrospective study, no other specific risk factors predicted an increased need for removal or exchange of tunneled hemodialysis catheters.

Adolescent↗
PubMed2004

Frequently asked questions: iodinated contrast agents.

Although iodinated contrast agents are safe and widely used, adverse events occur and questions remain about their use, safety, and interactions. Some questions are easily answered and others still require extensive investigation. For one frequent question--is informed consent necessary before all contrast media injections--the simple answer is no. Another question concerns use of contrast media in patients with prior reactions or allergies. Contrast agents can be safely used in such patients, but special care must be taken to be aware of what the previous reaction was and to be ready to treat any reaction. The protective role of pre-treatment with steroids is well established for minor reactions, but they may not prevent major reactions. It is important to realize that even life-threatening, anaphylactoid reactions are not the result of a true allergy to contrast media. Many questions arise about contrast agent-induced nephropathy. Baseline serum creatinine values should be obtained in patients who are at risk, not all patients. The incidence and natural history of contrast agent-induced nephropathy remain unclear. It occurs only in patients with compromised renal function before contrast agent injection, but even patients with normal serum creatinine levels can have renal dysfunction. Calculated creatinine clearance is a better way to determine risk and to follow this complication. The outcome in almost all patients is benign, with progression to end-stage renal disease being rare. The major risk factors, in addition to renal dysfunction, are long-standing diabetes mellitus, dehydration, and use of other nephrotoxic medications. Recent work in preventing and ameliorating contrast agent-induced nephropathy with N-acetyl cysteine, substitution of an isosmolal nonionic contrast agent, and various hydration regimens has been promising. Another common concern is use of iodinated contrast agents in pregnant or breast-feeding women. In both cases, there is no evidence of harm to the fetus or infant, but it is prudent to weigh the theoretical risks and benefits and avoid contrast agent administration unless it is truly necessary.

Contrast Media↗
PubMed2002

Long-term results and quality of life in patients treated with transjugular intrahepatic portosystemic shunts.

OBJECTIVE: The purpose of our study was to determine long-term survival, shunt patency, and quality of life in patients after creation of a transjugular intrahepatic portosystemic shunt (TIPS). MATERIALS AND METHODS: We followed up 103 patients who underwent TIPS for a mean of 20.10 +/- 25.58 months (range, 1 day-92 months). Various statistical methods were used to analyze long-term survival, shunt patency, and correlation with Child-Pugh classification and indications for TIPS. The Rand 36-Item Health Survey 1.0 was used to assess quality of life over time. RESULTS: The cumulative survival rate was 68%, 60%, 50%, 41%, and 41% at years 1-5, respectively. The cumulative survival rate was significantly higher for patients classified as Child-Pugh class A or B versus those classified as class C (p < 0.01), as well as for patients with the original indication of variceal bleeding versus refractory ascites or hydrothorax (p < 0.01). No significant difference in survival rates was found between patients with Child-Pugh A and those with Child-Pugh B. The cumulative primary patency rate was 50%, 34%, 21%, 13%, and 13% at years 1-5, respectively, with assisted patency rate of 80%, 61%, 46%, 42%, and 36%. Cumulative secondary patency rate was 85%, 64%, 55%, 55%, and 55% at years 1-5. Mean follow-up time in 33 patients who completed quality-of-life questionnaires with one follow-up was 17.46 months. Scores after TIPS in all nine of the health categories were higher than those preprocedure with statistically significant improvement in four categories. The second follow-up was completed by 21 patients at a mean of 30.58 months after TIPS creation. Both scores after TIPS were higher than those before TIPS, and scores in five categories were further improved at the second surveillance (p < 0.0, only for health change), whereas in four categories, the scores were slightly worse. CONCLUSION: TIPS has positive efficacy both for controlling bleeding or ascites and for improving the quality of life. The precise impact of TIPS on long-term survival, however, requires further clarification.

Adult↗
PubMedDate not supplied

Utility of covered stents for revision of aging failing synthetic hemodialysis grafts: a report of three cases.

Three aging failing hemodialysis polytetrafluoroethylene bypass shunts, average age 44 months, previously percutaneously revised with balloon angioplasty, presented with pseudoaneurysms and recurrent thrombosis. All were treated with percutaneous covered stent placement within their affected limbs. One graft was ligated 1 month after treatment for infected overlying skin ulcer, though this graft was subsequently surgically revised with interposition graft and the covered stent portion remains functional at 19 month follow-up. The 18- and 13- month follow-up of the remaining 2 patients shows that the covered stents remained patent and they are functional and being successfully and routinely punctured for dialysis. In this elderly population, the use of covered stents may prolong the functional life of failing hemodialysis bypass grafts, reducing the number of percutaneous and surgical interventions and further sparing other vascular access sites.

Aged↗