Meaningful reductions in SSI can be achieved by implementing a multidisciplinary care bundle at a hospital-wide level.

Object The surgical treatment of tumors located near eloquent cortex carries a high risk of inducing worsening neurological deficits. Intraoperative electrocorticography techniques have been developed to help identify these areas at the time of surgery in an effort to minimize such risks. The optimal anesthetic technique for conducting these procedures, however, has never been determined. Methods The authors conducted a retrospective study to compare patients who underwent intraoperative motor mapping between September 2000 and May 2002. Demographic and neurophysiological monitoring data were collected from the hospital records. Patients were divided into two groups based on the anesthetic technique used for surgery: in Group 1 general anesthesia was used, and in Group 2 conscious sedation. Group 1 comprised 24 patients (mean age 47 years) with 16 right- and eight left-sided lesions. Group 2 consisted of 21 patients (mean age 46 years) with 18 right- and three left-sided lesions. Pathological diagnoses were similar between the two groups. Motor stimulation was elicited in 12 patients (50%) in Group 1 and in 21 patients (100%) in Group 2 (p < 0.001). In addition, the mean stimulation amplitude required was significantly higher (13 mA) in patients in whom conscious sedation was used as opposed to general anesthesia (5 mA, p < 0.0001). Electrographic evidence of seizures was seen in 29% of Group 1 cmpared with 10% of Group 2 patients (p > 0.05). Conclusions The use of conscious sedation as an anesthetic technique for motor mapping not only improves the chances of achieving successful stimulation and identification of motor cortex in relationship to the lesion, but it also allows for repetitive monitoring of the patient's motor function during resection of the lesion.

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This paper presents an exploratory study for identification and quantification of the economic benefits or implications associated with wing cost variations. A hierarchical cost model structure is used to determine life cycle effects of design and manufacturing alternatives for the major structural components of the wing of a High Speed Civil Transport aircraft concept. Preliminary results are presented relating the effects of up to a 25% variation in wing cost to overall manufacturing and operational returns on investment. It was discovered that a 25% reduction in wing costs, relative to a baseline wing, results in approximately a 3% increase in return on investment for the manufacturer. In addition, deviations in wing cost of 10% and 25% yielded acquisition price differences of 2.25% and 6.0% respectively. These relatively small percentage differences in acquisition costs produced no significant changes in operational costs of the aircraft. Small changes were evident in the costs of financing and depreciating the aircraft, but these minor differentials had a negligible effect on the airline return on investment. MotivationAerospace manufacturers today are searching for techniques to gain a sustainable, competitive advantage in the global marketplace. For the United States aerospace and defense industries, a major issue is whether too much attention being paid to the "bottom line" will dull the U. S.' technological edge 1 . The many recent customer requirements emphasizing greater affordability may lead to a deemphasis of leading-edge technology. The amount of benefits that can be realized by introducing technological improvements into a new

An integrated design and manufacturing approach allows economic decisions to be made that reflect an entire system design as a whole. To achieve this objective, we have developed and utilized integrated cost and engineering models within a focused design perspective. A framework for the integrated design of an aircraft system with a combined performance and economic perspective is described in this article. This framework is based on the concept of Design Justification using a Design-for-Economics approach. We have developed a knowledge-based system that can be used to evaluate aircraft structural concept material and process selections. The framework consists of the knowledge-based system, integrated with numerical analysis tools including an aircraft performance/sizing code and a life-cycle cost analysis code. Production cost estimates are applied for evaluation of process trades at the subcomponent level of design. Life-cycle cost estimates are used for evaluation of process trades at the system level. Results of a case study are presented for several advanced wing structural concepts for a future supersonic commercial transport aircraft. Cost versus performance studies indicate that a high-speed civil transport aircraft with a hybrid wing structural concept, though more expensive to manufacture than some homogeneous concepts, can have lower direct operating costs due to a lower take-off gross weight and less mission fuel required.