Use of fluorescence imaging and indocyanine green during colorectal surgery: Results of an intercontinental Delphi survey

BACKGROUND: Fluorescence imaging with indocyanine green is increasingly being used in colorectal surgery to assess anastomotic perfusion, and to detect sentinel lymph nodes. METHODS: In this 2-round, online, Delphi survey, 35 international experts were asked to vote on 69 statements pertaining to patient preparation and contraindications to fluorescence imaging during colorectal surgery, indications, technical aspects, potential advantages/disadvantages, and effectiveness versus limitations, and training and research. Methodological steps were adopted during survey design to minimize risk of bias. RESULTS: More than 70% consensus was reached on 60 of 69 statements, including moderate-strong consensus regarding fluorescence imaging's value assessing anastomotic perfusion and leak risk, but not on its value mapping sentinel nodes. Similarly, although consensus was reached regarding most technical aspects of its use assessing anastomoses, little consensus was achieved for lymph-node assessments. Evaluating anastomoses, experts agreed that the optimum total indocyanine green dose and timing are 5 to 10 mg and 30 to 60 seconds pre-evaluation, indocyanine green should be dosed milligram/kilogram, lines should be flushed with saline, and indocyanine green can be readministered if bright perfusion is not achieved, although how long surgeons should wait remains unknown. The only consensus achieved for lymph-node assessments was that 2 to 4 injection points are needed. Ninety-six percent and 100% consensus were reached that fluorescence imaging will increase in practice and research over the next decade, respectively. CONCLUSION: Although further research remains necessary, fluorescence imaging appears to have value assessing anastomotic perfusion, but its value for lymph-node mapping remains questionable

Manufacturing flow line systems: a review of models and analytical results

The most important models and results of the manufacturing flow line literature are described. These include the major classes of models (asynchronous, synchronous, and continuous); the major features (blocking, processing times, failures and repairs); the major properties (conservation of flow, flow rate-idle time, reversibility, and others); and the relationships among different models. Exact and approximate methods for obtaining quantitative measures of performance are also reviewed. The exact methods are appropriate for small systems. The approximate methods, which are the only means available for large systems, are generally based on decomposition, and make use of the exact methods for small systems. Extensions are briefly discussed. Directions for future research are suggested.National Science Foundation (U.S.) (Grant DDM-8914277

A review of the guidelines for ABC stock control

The paper summarises the methods promulgated in the literature for the design and maintenance of an effective inventory control system. Surprisingly, when it comes to putting theory into practice, the directives are often contradictory or opaque and their logic is inconsistent. Several published cases are dissected to try and rectify this parlous situation. In fact, the exercise soon reveals the heart of the problem. The classic EOQ model ignores the part played at the supplier&rsquo;s end by efficient and responsive warehouse and transport operations. These activities depend greatly upon good advanced resource planning, which in turn is able to benefit from regular, cyclic, stock replenishment procedures.<br /

Assembly Line Balancing with Multiple Stations

A case is stated for extending the techniques of assembly line balancing to provide for the parallel operation of identical stations, where this leads to a reduction in idle time. The practical implications of operating with this type of system are discussed, both for the stations themselves and the line as a whole, with reference to various classifications of assembly line, and ways in which balancing can be made to fit into an overall strategy for production line design are touched upon. Two distinct types of computer program have been developed to enable multiple stations to become a recognised feature incorporated into "heuristic" line balancing, rather than an appendage to be applied ad hoc by industrial engineers when current techniques have proven inadequate. One approach is based on a more sophisticated version of the `positional weight' method while the other relies on the contrasting philosophy of the "random generation" method, and a comparison is made of their relative success in solving two assembly line problems, and their potential from an industrial viewpoint.