Abdominal aortic aneurysm sac behavior following Cook Zenith graft implantation: a five-year follow-up assessment of 212 cases

AIM: Aneurysm shrinkage is an expected outcome after stent-grafting for abdominal aortic aneurysm (AAA). A worrying problem following repair is progressive enlargement indicating persistent sac pressurization: in this setting not all grafts are equal. The Cook Zenith device (CZ) became available on the European market in 1999. While multicenter studies on the device have shown favorable clinical results at mid-term follow-up, few have focused on sac behavior. This study evaluated AAA sac behavior and predictive factors of its evolution by assessing the five-year results obtained with the CZ graft in a single-institution experience. METHODS: All consecutive elective surgery patients treated with a CZ graft for infrarenal aortic or aortoiliac aneurysm repair from January 2000 to November 2004 in our institution were included prospectively in the study and followed at 1, 6, 12, 18, 24 months and yearly thereafter. Pre-, intra- and postoperative data were recorded in a computerized database. Computed tomography (CT) scans were reviewed by a senior radiologist to identify any abnormalities including endoleak and graft malfunction. Pre- and postoperative maximum sac diameters were derived from measurements of CT findings and then compared. A change of at least 8 mm in sac size was considered significant. Overall results are expressed according to the Committee on Reporting Standards of AAA treatment. Factors that may have influenced sac behavior were analyzed by dividing the patients into 3 groups according to whether the sac diameter remained unchanged (group 1), had increased (group 2) or regressed (group 3). Statistical analysis of the demographic and CT-scan data was then performed. RESULTS: The study sample was 212 consecutive patients (mean age 72.8+/-9.0 years); the mean aneurysm diameter before treatment was 55.5+/-9.8 mm. All stent grafts were successfully implanted. The 30-day mortality rate was 0.94% (2/212); the morbidity rate was 11.7% (25/212). The primary technical success rate was 93.40%; the assisted primary technical success and secondary technical success rates were 96.63% and 99.52%, respectively. The mean follow-up period was 17.7+/-14.7 (1-60) months. The cumulative survival probability was 94%, 84.2%, and 72.9% at 12, 24, and 36 months, respectively. The endoleak-free survival probabilities at 12 and 24 months were 75.7% and 62.8%, respectively. The free of intervention survival rates were 82.1%, 68.9% and 60.6% at 12, 24 and 38 months, respectively. At five years follow-up, the overall clinical success rate was 49.5%. If changes in sac diameter occurred, they were noted at 13 months on average. Sac size remained unchanged in 115 (54.3%) patients (group 1), increased in 9 (4.2%) (group 2), and regressed in 88 (41.5%) (group 3). Neither preoperative patient demographics nor aneurysm characteristics were found to be predictive of sac behavior. Aortouniliac graft configuration was predictive of sac shrinkage (P=0.020). Endoleak was more frequent among patients in groups 1 (27/115; 23%) and 2 (5/9; 56%) than among those in group 3 (9/88;10%) (P=0.001). Reduction in aneurysm sac diameter was less marked in patients with any type of endoleak (P=0.0003). CONCLUSION: The CZ grafts offered satisfactory overall results up to five years of follow-up; nevertheless, sac diameter increased in 4.25% of patients. Endoleak was a predictive factor of a lack of sac shrinkage, while aortouniliac graft configuration was predictive of sac shrinkage.     

Anaplastic cancers of the thyroid. Is healing possible?

OBJECTIVE: Thyroid anaplastic carcinoma is associated with a very poor prognosis. The goal of this study was to determine whether an aggressive treatment is worthwhile. PATIENTS AND METHODS: Of 22 thyroid anaplastic carcinomas confirmed with immunohistochemistry, 17 were judged eligible for surgery. Total thyroidectomy was planned in all patients. Frozen section of the lower lateral lymph nodes was routinely performed and in case of involvement (n = 9), a modified radical neck dissection was carried out. Fractionated radiotherapy was started within 5 weeks following surgery: 6,000 cGy was delivered on the thyroid area and all involved areas while 4,500 cGy was delivered on the lymph nodes of the neck and of the superior mediastinum when non involved. RESULTS: The three patients without distant metastasis, with thyroid removal considered as complete, were still free of disease 10, 12 and 13 years later. One of these patients had been initially considered inoperable and was operated later when a combination of radiotherapy and chemotherapy obtained a decrease of the tumor. All other patients, 13 with incomplete removal and one with pulmonary metastasis died from their cancer; the median of the survival was 7 months. CONCLUSION: When anaplastic carcinoma is suspected on clinical appearance, the diagnosis should be rapidly confirmed with percutaneous biopsy and immunohistochemistry. If a lymphoma is found, surgery is not indicated. Our results demonstrate that except for widely infiltrating tumors or distant metastasis, a complete removal of the tumor should be attempted as soon as possible. Surgery should be followed with hyperfractionated radiotherapy. Multimodal therapy may result in long-term survival. A patient free of disease at 5 years may be considered as definitively cured.     

Acute respiratory failure in the elderly: etiology, emergency diagnosis and prognosis

Introduction

Our objectives were to determine the causes of acute respiratory failure (ARF) in elderly patients and to assess the accuracy of the initial diagnosis by the emergency physician, and that of the prognosis.

Method

In this prospective observational study, patients were included if they were admitted to our emergency department, aged 65 years or more with dyspnea, and fulfilled at least one of the following criteria of ARF: respiratory rate at least 25 minute^-1; arterial partial pressure of oxygen (PaO₂) 70 mmHg or less, or peripheral oxygen saturation 92% or less in breathing room air; arterial partial pressure of CO₂ (PaCO₂) ≥ 45 mmHg, with pH ≤ 7.35. The final diagnoses were determined by an expert panel from the completed medical chart.

Results

A total of 514 patients (aged (mean ± standard deviation) 80 ± 9 years) were included. The main causes of ARF were cardiogenic pulmonary edema (43%), community-acquired pneumonia (35%), acute exacerbation of chronic respiratory disease (32%), pulmonary embolism (18%), and acute asthma (3%); 47% had more than two diagnoses. In-hospital mortality was 16%. A missed diagnosis in the emergency department was noted in 101 (20%) patients. The accuracy of the diagnosis of the emergency physician ranged from 0.76 for cardiogenic pulmonary edema to 0.96 for asthma. An inappropriate treatment occurred in 162 (32%) patients, and lead to a higher mortality (25% versus 11%; p < 0.001). In a multivariate analysis, inappropriate initial treatment (odds ratio 2.83, p < 0.002), hypercapnia > 45 mmHg (odds ratio 2.79, p < 0.004), clearance of creatinine < 50 ml minute^-1 (odds ratio 2.37, p < 0.013), elevated NT-pro-B-type natriuretic peptide or B-type natriuretic peptide (odds ratio 2.06, p < 0.046), and clinical signs of acute ventilatory failure (odds ratio 1.98, p < 0.047) were predictive of death.

Conclusion

Inappropriate initial treatment in the emergency room was associated with increased mortality in elderly patients with ARF.     

Validation of laser diffraction method as a substitute for cascade impaction in the European Project for a Nebulizer Standard.

The project for a European standard testing procedure to characterize nebulizers in terms of particle size distribution has been based on using the Andersen-Marple personal cascade impactor model 298 (A-MPCI) with a sodium fluoride reference solution. In the present study methods based on laser diffraction (Mastersizer-X) and time-of-flight (TOF)(APS) and another cascade impactor (GS1-CI) were compared with the A-MPCI. Two types of nebulizer (Pari LC+ and Microneb) were tested with all apparatuses, and a third type of nebulizer (NL9) was tested with the A-MPCI and Mastersizer-X. Nebulizers were charged with a solution of sodium fluoride in conditions reproducing the European Committee for Normalization (CEN) protocol. There was no difference between the Mastersizer-X and the A-MPCI or between the GS1-CI and the A-MPCI in terms of mass median aerodynamic diameter (MMAD). Comparison between the APS and the A-MPCI showed a significant difference with the Microneb. The geometric standard deviations (GSD) obtained with the A-MPCI were on average 10% greater than GSD obtained with the other apparatuses, but the differences were not statistically significant. We conclude that laser diffraction can be used for particle size distribution in the context of the European standard, and that the Mastersizer-X is particularly interesting for industrial practice in view of its simplicity and robustness.