Population‐based cohort study of outcomes following cholecystectomy for benign gallbladder diseases

Background The aim was to describe the management of benign gallbladder disease and identify characteristics associated with all‐cause 30‐day readmissions and complications in a prospective population‐based cohort. Methods Data were collected on consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing all‐cause 30‐day readmissions and complications were analysed by means of multilevel, multivariable logistic regression modelling using a two‐level hierarchical structure with patients (level 1) nested within hospitals (level 2). Results Data were collected on 8909 patients undergoing cholecystectomy from 167 hospitals. Some 1451 cholecystectomies (16·3 per cent) were performed as an emergency, 4165 (46·8 per cent) as elective operations, and 3293 patients (37·0 per cent) had had at least one previous emergency admission, but had surgery on a delayed basis. The readmission and complication rates at 30 days were 7·1 per cent (633 of 8909) and 10·8 per cent (962 of 8909) respectively. Both readmissions and complications were independently associated with increasing ASA fitness grade, duration of surgery, and increasing numbers of emergency admissions with gallbladder disease before cholecystectomy. No identifiable hospital characteristics were linked to readmissions and complications. Conclusion Readmissions and complications following cholecystectomy are common and associated with patient and disease characteristics

The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set

Background Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables. Methods Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set. Results Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001). Conclusions The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy

Evaluation of appendicitis risk prediction models in adults with suspected appendicitis

Background Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis. Methods A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis). Results Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent). Conclusion Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified

Gastric adenocarinoma of the upper oesophagus: A literature review and case report.

BACKGROUND: Ectopic gastric mucosa (EGM) otherwise termed gastric heterotopia or gastric inlet patch occurs in approximately 2.5% of the population. Adenocarcinoma uncommonly involves the upper oesophagus, rarely arising from gastric heterotopia or submucosal glands. Currently, there are 58 cases in the literature of oesophageal adenocarcinoma arising within areas of EGM. To date no paper has differentiated between gastric or intestinal type adenocarcinoma. This case, which describes adenocarcinoma arising within EGM, exhibited a different immunophenotype reminiscent of gastric type glands, in the absence of intestinal metaplasia. This case should be regarded as a different type of carcinoma, consistent with a non-Barrett's oesophagus-associated adenocarcinoma. CLINICAL PRESENTATION: A 63year old female presented with a three month history of progressive cervical dysphagia with no associated weight loss or general malaise. Gastroscopy revealed a suspicious lesion at the cricopharyngeus. Positron emission tomography demonstrated a metabolically active primary lesion without evidence of distant disease. The patient received neo-adjuvant chemotherapy followed by a three stage total oesophagectomy. Histology demonstrated a moderately differentiated adenocarcinoma with gastric immunophenotype and background changes of gastric heterotopia. CONCLUSION: EGM is common but scarcely biopsied for evidence of dysplasia or adenocarcinoma. Whilst malignant progression is rare it is important that endoscopists are aware of the potential. Determining the exact type of adenocarcinoma may have implications for therapeutic approaches. Recognition of EGM at endoscopy may identify patients at greater risk of developing adenocarcinomas of the proximal oesophagus, however, this relationship and the necessity for screening requires more study

Instinct, intuition and surgical decision-making

When to go with your gut, and when to seek a second opinion. </jats:p

The Recombination Operator, its Correlation to the Fitness Landscape and Search Performance

A common misconception in evolutionary algorithms (EAs) is that one recombination operator is universally better than another. In fact, a recombination operator will only get better performance on a function if it incorporates some knowledge about that function--called tuning it to the function&apos;s fitness landscape. In this thesis we identify three ways in which a recombination operator can be tuned to a real-valued landscape: distance, directionality, and distributional bias. We empirically show that a directionally tuned recombination operator gives better search performance than an untuned operator. We also show that a recombination operator that is tuned to one landscape can be mis-tuned to a similar landscape. In addition we find several surprises that contradict our initial intuition but yield to further analysis. For example one interesting observation is a decrease in the number of individuals on the global optimum. We show this to be caused by the attractive pull of a larger g..