Determinants of prolonged mechanical ventilation after coronary artery bypass grafting

BACKGROUND: Early extubation of cardiac surgical patients enhances ambulation, improves cardiopulmonary function, and can lead to savings in health care costs. METHODS: We retrospectively examined the role of 48 variables in determining the period of ventilatory support in 507 patients having coronary artery bypass grafting. RESULTS: Fifteen (< 3%) of 507 patients required ventilatory support in excess of 24 hours. Among the remaining patients, extubation was achieved early (< or = 8 hours) (mean time, 5.65 +/- 1.31 hours) in 53% and late (> 8 hours) (mean time, 13.7 +/- 3.4 hours) in 47%. Logistic and linear multivariate regression analyses implicated increased age, New York Heart Association functional class IV, intraoperative fluid retention, postoperative intraaortic balloon pump requirement, and bank blood transfusions as predictors of late extubation. Also, the linear regression linked lower body weight and number of anastomoses (or grafts) to increased mechanical ventilatory support. CONCLUSIONS: Analysis of the fluid balance and cardiopulmonary bypass data suggests that earlier extubation may be achieved by actively reducing fluid retention (eg, by hemoconcentration) and time on bypass (eg, normothermia). Finally, intensive care unit stay and postoperative length of stay were significantly lower in the early versus late extubation groups without an increase in pulmonary complications.     

Perianal mucinous adenocarcinoma

BACKGROUND: The treatment of toxic epidermal necrolysis (TEN) is usually based on the removal of the offending drug(s), fluid replacement, nutritional support, and local management. The mortality and morbidity, however, remain high and the death rate may be reduced to 10% only in special centers that use biologic dressings. Plasma exchange (PE) was proven efficacious in small series of patients and of no particular value in others. METHODS: Seven patients suffering from severe TEN covering 30%-80% of body surface area and having two or four mucous membranes involved, were included in this open study. Malignancy (Hodgkin's disease, brain tumor) and a variety of medicaments (carbamazepine, allopurinol, diphenylhydantoin, cefaclor, amoxicyllin with clavullanic acid) were considered as causally implicated. One to four PEs of 2.5 L were given on alternate days in six patients and on a daily basis in the seventh. RESULTS: All patients recovered successfully from their disease. No new lesions appeared after the first PE in four patients. Neither adverse reactions from this therapy nor sequelae from TEN were observed after a long follow-up lasting up to 8 years. CONCLUSIONS: Although PE is expensive and requires easy venous access to be performed, it could be listed in the first line of TEN therapy. The method is safe and efficacious, providing prompt relief from pain and rapid cessation of necrolysis. The alternate day PEs are considered preferable to the everyday regimen.     

The Plate Model: a visual method of teaching meal planning. DAIS Project Group. Diabetes Atherosclerosis Intervention Study

Dietitians from Canada, Finland, France, and Sweden have explored methods of teaching meal planning to persons with diabetes and dyslipidemia in the Diabetes Atherosclerosis Intervention Study. The Plate Model, a method commonly used in Europe, is a simple alternative to the traditional exchange-based method for teaching meal planning. In this visual method, a dinner plate serves as a pie chart to show proportions of the plate that should be covered by various food groups. Portions of foods and appropriate food choices can be depicted for meals and snacks in assorted forms of the model. Methods of presenting the model range from professional photography to hand-drawn sketches and displays of food replicas. Benefits of the model for adult learners include enhancement of the connection between dietary theory and practice, promotion of memory retention and understanding through visual messages, and experience of a positive approach to nutrition counseling. Various cuisines and festive foods can be incorporated into the model. The Plate Model offers a meal planning approach that is simple and versatile. The effectiveness of the model and its applications to other populations need to be evaluated.     

Target volume and indications of radiotherapy in breast carcinoma

Breast-conserving surgery is now commonly used to treat breast cancer. While mastectomy has been the traditional treatment for ductal carcinoma in situ, it is felt to be excessive in most cases. A great effort has been made to identify pathobiological characteristics of DCIS that can be used to identify patients best suited for wide local excision vs. wide local excision and breast irradiation. Mastectomy and conservative surgery plus irradiation offer a similar outcome in patients with early stage invasive breast cancer. Radiotherapy has not been shown to improve survival but is able to reduce significantly the rate of local recurrence, which is regarded as a very undesirable outcome. There is still controversy concerning the necessity of irradiation of the breast in all patients. Analysis of predictors of outcome cannot identify a subgroup of patients with a very low risk for local breast recurrence who might not require radiation therapy. In premenopausal, node-positive breast cancer patients XRT has a beneficial effect not only on locoregional but also on systemic recurrences. Radiotherapy has to be integrated for a pre- or postoperative consolidation in new treatment concepts for locally advanced breast cancer which use primary chemotherapy and immediate or subsequent breast radiation. Radiation of internal mammary chain and supraclavicular fossa after conservative surgery does not lead to an increase in clinically important skin or pulmonary complications. Its role is being evaluated in current multicentre studies.     

Interleukin 2 and interferon alpha-2a do not improve anti-tumour activity of 5-fluorouracil in advanced colorectal cancer

Treatment using a combination of 5-fluorouracil (5-FU), interferon-alpha (IFN alpha-2a) and interleukin 2 (IL-2) has been shown to mediate disease regression in selected patients with advanced colorectal cancer. This phase II study was designed to evaluate the anti-tumour activity and toxicity of the combination of IL-2, IFN alpha-2a and 5-FU in patients with advanced colorectal cancer. Forty-four patients with metastatic colorectal cancer were treated, predominantly on an outpatient basis, with subcutaneous IFN alpha-2a and IL-2 three times per week followed by once a week bolus intravenous 5-FU injections. There were six (14%) partial responses among the 43 evaluable patients [95% confidence interval (CI) 5-28%]. Twenty-four patients had stable disease (56%) and 13 patients (30%) showed progressive disease. The median time to progressive disease in 43 patients was 19 weeks (range 2-72 weeks) and in responders 34 weeks (range 24-30 weeks). The median overall survival was 47 weeks (range 2-85 weeks) and in responders 60 weeks (range 35-71 weeks). Treatment-related toxic effects included fatigue, nausea and vomiting. Granulocytopenia was the main reason for the dose reductions or treatment interruptions in 32 out of 44 patients. One patient died of toxicity due to renal failure. Serial assessments of immunophenotyping and cytolytic activities of peripheral blood lymphocytes did not show changes in the numbers of circulating natural killer (NK) cells or in the levels of NK and lymphokine-activated killer (LAK) cytolytic activities. This regimen of IL-2 and IFN alpha-2a with 5-FU has only modest anti-tumour activity in advanced colorectal cancer.     

Case report. Aortic pseudoaneurysm with aortobronchial fistula: diagnosis with CT angiography

We report the case of an 82-year-old man with a 12-month history of recurrent hemoptysis caused by an aortobronchial fistula. Twenty-five years earlier, the patient underwent placement of an aortic graft for aortic transection sustained in a motor vehicle accident. Chest radiography and bronchoscopy showed nonspecific abnormalities. We emphasize the role of CT angiography with 2D and 3D reconstructions for the diagnosis of and surgical planning for this rare but potentially lethal aortic postoperative complication.     

Effect of electrostatic interaction on phase separation behaviour of chitin crystallite suspensions

Optical and electron microscopy were used to observe the dynamics of the phase separation in aqueous chitin suspensions prepared by HCl hydrolysis of crab chitin. Freeze-fracture transmission electron microscopy reveals that chitin crystallites are partially aggregated in the suspension and have an average length of 200 nm and an average width of 8 nm. They exhibit a positive surface charge of approximately 0.5 e/nm2 when fully protonated. The liquid crystal-forming aqueous suspensions of such crystallites are investigated through phase diagrams and Zeta potential measurements for different ionic strength. Exposure of the suspension to a low concentration of univalent electrolyte has a negligible effect on phase separation because of the contribution of the charged crystallites themselves to the ionic strength. The thickness of the effective repulsive layer is estimated both from the phase diagrams according to Onsager's theory and from the computed interaction energy derived from the Poisson-Boltzmann equation using the experimental Zeta potential as surface potential. When the contribution of crystallites to the ionic strength is taken into account and an hypothetical linear charge density close to the Manning limit is assumed, there is good agreement with the Debye length.