The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy

Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations. Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves. Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p  90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score. Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care

Temperature and developmental plasticity during embryogenesis in the Atlantic cod Gadus morhua L.

Atlantic cod (Gadus morhua L.) embryos were reared at 4 degreesC, 7 degreesC, and 10 degreesC, and the relative timing of developmental events was characterized, with particular reference to myotomal muscle. Embryos started to feed at an apparently equivalent stage of development, so comparisons were made between temperature groups on the basis of percentage of time to first feeding and somite stage. No differences were found in the time of hatching or timing of appearance of the otic placode, unpaired median fin fold, gut lumen, otic vesicle, lens of the eye, otoliths, first muscular contractions, swim bladder, and hindgut, or in the rate of development of somites, myotubes, myofibrils, and acetylcholinesterase activity over the temperature range studied. In contrast, closure of the blastopore occurred late with respect to segmentation at higher temperatures, at the 3-somite, 10-somite, and 12-somite stages at 4 degreesC, 7 degreesC, and 10 degreesC respectively. Muscle cellularity was also markedly altered in the 10 degreesC group relative to the 4 degreesC and 7 degreesC groups. Larvae reared at 10 degreesC had significantly more ( +14%) deep white fibers at hatch (P&lt;0.001), whereas numbers of superficial red fibers remained unchanged. It is suggested that differences in muscle cellularity might be related to changes in the relative timing of epiboly, through differential proliferation of presomitic myogenic cells and/or their relative exposure to inductive signals.</p