The Impact of Temporal Variation in Indocyanine Green Administration on Tumor Identification During Fluorescence Guided Breast Surgery.

BACKGROUND: On average, 21% of women in the USA treated with Breast Conserving Surgery (BCS) undergo a second operation because of close positive margins. Tumor identification with fluorescence imaging could improve positive margin rates through demarcating location, size, and invasiveness of tumors. We investigated the technique's diagnostic accuracy in detecting tumors during BCS using intravenous indocyanine green (ICG) and a custom-built fluorescence camera system. METHODS: In this single-center prospective clinical study, 40 recruited BCS patients were sub-categorized into two cohorts. In the first 'enhanced permeability and retention' (EPR) cohort, 0.25 mg/kg ICG was injected ~ 25 min prior to tumor excision, and in the second 'angiography' cohort, ~ 5 min prior to tumor excision. Subsequently, an in-house imaging system was used to image the tumor in situ prior to resection, ex vivo following resection, the resection bed, and during grossing in the histopathology laboratory to compare the technique's diagnostic accuracy between the cohorts. RESULTS: The two cohorts were matched in patient and tumor characteristics. The majority of patients had invasive ductal carcinoma with concomitant ductal carcinoma in situ. Tumor-to-background ratio (TBR) in the angiography cohort was superior to the EPR cohort (TBR = 3.18 ± 1.74 vs 2.10 ± 0.92 respectively, p = 0.023). Tumor detection reached sensitivity and specificity scores of 0.82 and 0.93 for the angiography cohort and 0.66 and 0.90 for the EPR cohort, respectively (p = 0.1051 and p = 0.9099). DISCUSSION: ICG administration timing during the angiography phase compared with the EPR phase improved TBR and diagnostic accuracy. Future work will focus on image pattern analysis and adaptation of the camera system to targeting fluorophores specific to breast cancer.

Perfect Registration Leads to Imperfect Performance: A Randomized Trial of Multimodal Intraoperative Image Guidance.

OBJECTIVE: To compare surgical safety and efficiency of 2 image guidance modalities, perfect augmented reality (AR) and side-by-side unregistered image guidance (IG), against a no guidance control (NG), when performing a simulated laparoscopic cholecystectomy (LC). BACKGROUND: Image guidance using AR offers the potential to improve understanding of subsurface anatomy, with positive ramifications for surgical safety and efficiency. No intra-abdominal study has demonstrated any advantage for the technology. Perfect AR cannot be provided in the operative setting in a patient; however, it can be generated in the simulated setting. METHODS: Thirty-six experienced surgeons performed a baseline LC using the LapMentor simulator before randomization to 1 of 3 study arms: AR, IG, or NG. Each performed 3 further LC. Safety and efficiency-related simulator metrics, and task workload (SURG-TLX) were collected. RESULTS: The IG group had a shorter total instrument path length and fewer movements than NG and AR groups. Both IG and NG took a significantly shorter time than AR to complete dissection of Calot triangle. Use of IG and AR resulted in significantly fewer perforations and serious complications than the NG group. IG had significantly fewer perforations and serious complications than the AR group. Compared with IG, AR guidance was found to be significantly more distracting. CONCLUSION: Side-by-side unregistered image guidance (IG) improved safety and surgical efficiency in a simulated setting when compared with AR or NG. IG provides a more tangible opportunity for integrating image guidance into existing surgical workflow as well as delivering the safety and efficiency benefits desired.

Metabolic phenotyping in clinical and surgical environments.

Metabolic phenotyping involves the comprehensive analysis of biological fluids or tissue samples. This analysis allows biochemical classification of a person's physiological or pathological states that relate to disease diagnosis or prognosis at the individual level and to disease risk factors at the population level. These approaches are currently being implemented in hospital environments and in regional phenotyping centres worldwide. The ultimate aim of such work is to generate information on patient biology using techniques such as patient stratification to better inform clinicians on factors that will enhance diagnosis or the choice of therapy. There have been many reports of direct applications of metabolic phenotyping in a clinical setting.

The role of technology in minimally invasive surgery: state of the art, recent developments and future directions.

The diffusion of minimally invasive surgery has thrived in recent years, providing substantial benefits over traditional techniques for a number of surgical interventions. This rapid growth has been possible due to significant advancements in medical technology, which partly solved some of the technical and clinical challenges associated with minimally invasive techniques. The issues that still limit its widespread adoption for some applications include the limited field of view; reduced manoeuvrability of the tools; lack of haptic feedback; loss of depth perception; extended learning curve; prolonged operative times and higher financial costs. The present review discusses some of the main recent technological advancements that fuelled the uptake of minimally invasive surgery, focussing especially on the areas of imaging, instrumentation, cameras and robotics. The current limitations of state-of-the-art technology are identified and addressed, proposing future research directions necessary to overcome them.

A Systematic Review of the Impact of Dedicated Emergency Surgical Services on Patient Outcomes.

OBJECTIVE: This review aims to assess the impact of implementing dedicated emergency surgical services, in particular acute care surgery, on clinical outcomes. BACKGROUND: The optimal model for delivering high-quality emergency surgical care remains unknown. Acute Care Surgery (ACS) is a health care model combining emergency general surgery, trauma, and critical care. It has been adopted across the United States in the management of surgical emergencies. METHOD: A systematic review was performed after PRISMA recommendations using the MEDLINE, Embase, and Psych-Info databases. Studies assessing different care models and institutional factors affecting the delivery of emergency general surgery were included. RESULTS: Twenty-seven studies comprising 744,238 patients were included in this review. In studies comparing ACS with traditional practice, mortality and morbidity were improved. Moreover, time to senior review, delays to operating theater, and financial expenditure were often reduced. The elements of ACS models varied but included senior clinicians present onsite during office hours and dedicated to emergency care while on-call. Referrals were made to specialist centers with primary surgical assessments taking place on surgical admissions units rather than in the emergency department. Twenty-four-hour access to dedicated emergency operating rooms was also described. CONCLUSIONS: ACS models as well as centralized units and hospitals with dedicated emergency operating rooms, access to radiology and intensive care facilities (ITU) are all factors associated with improved clinical and financial outcomes in the delivery of emergency general surgery. There is, however, no consensus on the elements that constitute an ideal ACS model and how it can be implemented into current surgical practice.

Evaluating a Novel 3D Stereoscopic Visual Display for Transanal Endoscopic Surgery: A Randomized Controlled Crossover Study.

OBJECTIVE: To compare surgical performance with transanal endoscopic surgery (TES) using a novel 3-dimensional (3D) stereoscopic viewer against the current modalities of a 3D stereoendoscope, 3D, and 2-dimensional (2D) high-definition monitors. BACKGROUND: TES is accepted as the primary treatment for selected rectal tumors. Current TES systems offer a 2D monitor, or 3D image, viewed directly via a stereoendoscope, necessitating an uncomfortable operating position. To address this and provide a platform for future image augmentation, a 3D stereoscopic display was created. METHODS: Forty participants, of mixed experience level, completed a simulated TES task using 4 visual displays (novel stereoscopic viewer and currently utilized stereoendoscope, 3D, and 2D high-definition monitors) in a randomly allocated order. Primary outcome measures were: time taken, path length, and accuracy. Secondary outcomes were: task workload and participant questionnaire results. RESULTS: Median time taken and path length were significantly shorter for the novel viewer versus 2D and 3D, and not significantly different to the traditional stereoendoscope. Significant differences were found in accuracy, task workload, and questionnaire assessment in favor of the novel viewer, as compared to all 3 modalities. CONCLUSIONS: This novel 3D stereoscopic viewer allows surgical performance in TES equivalent to that achieved using the current stereoendoscope and superior to standard 2D and 3D displays, but with lower physical and mental demands for the surgeon. Participants expressed a preference for this system, ranking it more highly on a questionnaire. Clinical translation of this work has begun with the novel viewer being used in 5 TES patients.

Development and implementation of the Structured Training Trainer Assessment Report (STTAR) in the English National Training Programme for laparoscopic colorectal surgery.

BACKGROUND: There is a lack of educational tools available for surgical teaching critique, particularly for advanced laparoscopic surgery. The aim was to develop and implement a tool that assesses training quality and structures feedback for trainers in the English National Training Programme for laparoscopic colorectal surgery. METHODS: Semi-structured interviews were performed and analysed, and items were extracted. Through the Delphi process, essential items pertaining to desirable trainer characteristics, training structure and feedback were determined. An assessment tool (Structured Training Trainer Assessment Report-STTAR) was developed and tested for feasibility, acceptability and educational impact. RESULTS: Interview transcripts (29 surgical trainers, 10 trainees, four educationalists) were analysed, and item lists created and distributed for consensus opinion (11 trainers and seven trainees). The STTAR consisted of 64 factors, and its web-based version, the mini-STTAR, included 21 factors that were categorised into four groups (training structure, training behaviour, trainer attributes and role modelling) and structured around a training session timeline (beginning, middle and end). The STTAR (six trainers, 48 different assessments) demonstrated good internal consistency (α = 0.88) and inter-rater reliability (ICC = 0.75). The mini-STTAR demonstrated good inter-item reliability (α = 0.79) and intra-observer reliability on comparison of 85 different trainer/trainee combinations (r = 0.701, p = <0.001). Both were found to be feasible and acceptable. The educational report for trainers was found to be useful (4.4 out of 5). CONCLUSIONS: An assessment tool that evaluates training quality was developed and shown to be reliable, acceptable and of educational value. It has been successfully implemented into the English National Training Programme for laparoscopic colorectal surgery.

Is It Time to Centralize High-risk Cancer Care in the United States? Comparison of Outcomes of Esophagectomy Between England and the United States.

OBJECTIVE: To determine the difference in in-hospital mortality and length of hospital stay (LOS) after esophagectomy between the United States and England. BACKGROUND: Since 2001, complex procedures such as esophagectomy have been centralized in England, but in the United States no formal plan for centralization exists. METHODS: Patients who underwent esophagectomy for cancer between 2005 and 2010 were identified from the Nationwide Inpatient Sample (United States) and the Hospital Episodes Statistics (England). In-hospital mortality and LOS were compared. RESULTS: There were 7433 esophagectomies performed in 66 English hospitals and 5858 resections in 775 US hospitals; median number of resections per center per year was 17.5 in England and 2 in the United States. In-hospital mortality was greater in US hospitals (5.50% vs 4.20%, P = 0.001). In multiple regression analysis, predictors of mortality included patient age, comorbidities, hospital volume, and surgery performed in the United States [odds ratio (OR) = 1.20 (1.02-1.41), P = 0.03]. Median LOS was greater in the English hospitals (15 vs 12 days, P < 0.001). However, when subset analysis was done on high-volume centers in both health systems, mortality was significantly better in US hospitals (2.10% vs 3.50%, P = 0.02). LOS was also seen to decrease in the US high-volume centers but not in England. CONCLUSIONS: The findings from this international comparison suggest that centralization of high-risk cancer surgery to centers of excellence with a high procedural volume translates into an improved clinical outcome. These findings should be factored into discussions regarding future service configuration of major cancer surgery in the United States.

Inattention blindness in surgery.

BACKGROUND: Inattention blindness (IB) can be defined as the failure to perceive an unexpected object when attention is focussed on another object or task. The principal aim of this study was to determine the effect of cognitive load and surgical image guidance on operative IB. METHODS: Using a randomised control study design, participants were allocated to a high or low cognitive load group and subsequently to one of three augmented reality (AR) image guidance groups (no guidance, wireframe overlay and solid overlay). Randomised participants watched a segment of video from a robotic partial nephrectomy. Those in the high cognitive load groups were asked to keep a count of instrument movements, while those in the low cognitive load groups were only asked to watch the video. Two foreign bodies were visible within the operative scene: a swab, within the periphery of vision; and a suture, in the centre of the operative scene. Once the participants had finished watching the video, they were asked to report whether they had observed a swab or suture. RESULTS: The overall level of prompted inattention blindness was 74 and 10 % for the swab and suture, respectively. Significantly higher levels of IB for the swab were seen in the high versus the low cognitive load groups, but not for the suture (8 vs. 47 %, p < 0.001 and 90 vs. 91 %, p = 1.000, for swab and suture, respectively). No significant difference was seen between image guidance groups for attention of the swab or suture (29 vs. 20 %, p = 0.520 and 22 vs. 22 %, p = 1.000, respectively). CONCLUSIONS: The overall effect of IB on operative practice appeared to be significant, within the context of this study. When examining for the effects of AR image guidance and cognitive load on IB, only the latter was found to have significance.

Quantifying innovation in surgery.

OBJECTIVES: The objectives of this study were to assess the applicability of patents and publications as metrics of surgical technology and innovation; evaluate the historical relationship between patents and publications; develop a methodology that can be used to determine the rate of innovation growth in any given health care technology. BACKGROUND: The study of health care innovation represents an emerging academic field, yet it is limited by a lack of valid scientific methods for quantitative analysis. This article explores and cross-validates 2 innovation metrics using surgical technology as an exemplar. METHODS: Electronic patenting databases and the MEDLINE database were searched between 1980 and 2010 for "surgeon" OR "surgical" OR "surgery." Resulting patent codes were grouped into technology clusters. Growth curves were plotted for these technology clusters to establish the rate and characteristics of growth. RESULTS: The initial search retrieved 52,046 patents and 1,801,075 publications. The top performing technology cluster of the last 30 years was minimally invasive surgery. Robotic surgery, surgical staplers, and image guidance were the most emergent technology clusters. When examining the growth curves for these clusters they were found to follow an S-shaped pattern of growth, with the emergent technologies lying on the exponential phases of their respective growth curves. In addition, publication and patent counts were closely correlated in areas of technology expansion. CONCLUSIONS: This article demonstrates the utility of publically available patent and publication data to quantify innovations within surgical technology and proposes a novel methodology for assessing and forecasting areas of technological innovation.

Enhanced frontoparietal network architectures following "gaze-contingent" versus "free-hand" motor learning.

Longitudinal changes in cortical function are known to accompany motor skills learning, and can be detected as an evolution in the activation map. These changes include attenuation in activation in the prefrontal cortex and increased activation in primary and secondary motor regions, the cerebellum and posterior parietal cortex. Despite this, comparatively little is known regarding the impact of the mode or type of training on the speed of activation map plasticity and on longitudinal variation in network architectures. To address this, we randomised twenty-one subjects to learn a complex motor tracking task delivered across six practice sessions in either "free-hand" or "gaze-contingent motor control" mode, during which frontoparietal cortical function was evaluated using functional near infrared spectroscopy. Results demonstrate that upon practice termination, gaze-assisted learners had achieved superior technical performance compared to free-hand learners. Furthermore, evolution in frontoparietal activation foci indicative of expertise was achieved at an earlier stage in practice amongst gaze-assisted learners. Both groups exhibited economical small world topology; however, networks in learners randomised to gaze-assistance were less costly and showed higher values of local efficiency suggesting improved frontoparietal communication in this group. We conclude that the benefits of gaze-assisted motor learning are evidenced by improved technical accuracy, more rapid task internalisation and greater neuronal efficiency. This form of assisted motor learning may have occupational relevance for high precision control such as in surgery or following re-learning as part of stroke rehabilitation.

Radiofrequency-induced small bowel thermofusion: an ex vivo study of intestinal seal adequacy using mechanical and imaging modalities.

BACKGROUND: Bipolar radiofrequency (RF) induced tissue fusion is believed to have the potential to seal and anastomose intestinal tissue thereby providing an alternative to current techniques which are associated with technical and functional complications. This study examines the mechanical and cellular effects of RF energy and varying compressive pressures when applied to create ex vivo intestinal seals. METHODS: A total of 299 mucosa-to-mucosa fusions were formed on ex vivo porcine small bowel segments using a prototype bipolar RF device powered by a closed-loop, feedback-controlled RF generator. Compressive pressures were increased at 0.05 MPa intervals from 0.00 to 0.49 MPa and RF energy was applied for a set time period to achieve bowel tissue fusion. Seal strength was subsequently assessed using burst pressure and tensile strength testing, whilst morphological changes were determined through light microscopy. To further identify the subcellular tissue changes that occur as a result of RF energy application, the collagen matrix in the fused area of a single bowel segment sealed at an optimal pressure was examined using transmission electron microscopy (TEM). RESULTS: An optimal applied compressive pressure range was observed between 0.10 and 0.25 MPa. Light microscopy demonstrated a step change between fused and unfused tissues but was ineffective in distinguishing between pressure levels once tissues were sealed. Non uniform collagen damage was observed in the sealed tissue area using TEM, with some areas showing complete collagen denaturation and others showing none, despite the seal being complete. This finding has not been described previously in RF-fused tissue and may have implications for in vivo healing. CONCLUSIONS: This study shows that both bipolar RF energy and optimal compressive pressures are needed to create strong intestinal seals. This finding suggests that RF fusion technology can be effectively applied for bowel sealing and may lead to the development of novel anastomosis tools.

Simulated procedure rehearsal is more effective than a preoperative generic warm-up for endovascular procedures.

INTRODUCTION: Patient-specific simulated rehearsal (PsR) of a carotid artery stenting procedure (CAS) enables the interventionalist to rehearse the case before performing the procedure on the actual patient by incorporating patient-specific computed tomographic data into the simulation software. This study aimed to evaluate whether PsR of a CAS procedure can enhance the operative performance versus a virtual reality (VR) generic CAS warm-up procedure or no preparation at all. METHODS: During a 10-session cognitive/technical VR course, medical residents were trained in CAS. Thereafter, in a randomized crossover study, each participant performed a patient-specific CAS case 3 times on the simulator, preceded by 3 different tasks: a PsR, a generic case, or no preparation. Technical performances were assessed using simulator-based metrics and expert-based ratings. RESULTS: Twenty medical residents (surgery, cardiology, radiology) were recruited. Training plateaus were observed after 10 sessions for all participants. Performances were significantly better after PsR than after a generic warm-up or no warm-up for total procedure time (16.3 ± 0.6 vs 19.7 ± 1.0 vs 20.9 ± 1.1 minutes, P = 0.001) and fluoroscopy time (9.3 ± 0.1 vs 11.2 ± 0.6 vs 11.2 ± 0.5 minutes, P = 0.022) but did not influence contrast volume or number of roadmaps used during the "real" case. PsR significantly improved the quality of performance as measured by the expert-based ratings (scores 28 vs 25 vs 25, P = 0.020). CONCLUSIONS: Patient-specific simulated rehearsal of a CAS procedure significantly improves operative performance, compared to a generic VR warm-up or no warm-up. This technology requires further investigation with respect to improved outcomes on patients in the clinical setting.

Major incident preparation for acute hospitals: current state-of-the-art, training needs analysis, and the role of novel virtual worlds simulation technologies.

BACKGROUND: There is growing evidence that health systems in developed countries are poorly prepared to deal with major incidents. STUDY OBJECTIVES: This study aimed to determine the skills required for successful major incident response, the factors that contribute to a successful major incident exercise, and whether there is a role for using novel simulation training (virtual worlds) in preparing for major incidents. METHODS: This was a qualitative semi-structured interview study. Fourteen health care staff with experience of major incident planning and training in the United Kingdom were recruited. Interviews were content-analyzed to identify emergent themes. RESULTS: The aims and benefits of current exercises were categorized into three major themes: Organizational, Interpersonal, and Cognitive. Participants felt that the main objective of current exercises is to see how a major incident plan is implemented, rather than training individual staff. Communications was the most frequently commented-on area requiring improvement. Participants felt that lack of constructive feedback reduced the effectiveness of the exercises. All participants commented that virtual worlds technology could be successfully utilized for training. The creation of an immersive environment, increased training opportunity, and improved participant feedback were thought to be amongst the greatest benefits. CONCLUSION: There are clear deficiencies with current major incident preparation. Utilizing virtual worlds technology as an adjunct to existing exercises could improve training and response in the future.

The feasibility, safety and outcomes of laparoscopic re-operation for achalasia.

INTRODUCTION: Heller myotomy for achalasia is associated with a recurrence rate of around 10%, thus reoperative surgery is often necessitated. This paper aims to review the available literature on laparoscopic reoperation for achalasia in order to assess its feasibility and effectiveness. MATERIAL & METHODS: A Medline, Embase, Ovid, Cochrane database and Google(TM) Scholar search was performed with the following Mesh terms: "laparoscopic", "redo", "reoperative", "Heller's", "esophagomyotomy" and "achalasia". Outcomes of interest included patient demographics and details of primary procedure, operative details, intra- and post operative complications and symptom scores. RESULTS: Seven studies reported outcomes from 54 cases. Conversion occurred in 7% (4/54) of cases. Thirteen percent (7/54) of patients sustained intra-operative gastric or oesophageal perforation; however these were all noted and repaired intra-operatively leading to no subsequent morbidity. No deaths were reported. Pre- and post operative symptom scores were heterogeneous, however did appear to improve after the procedure. DISCUSSION: This review demonstrates that laparoscopic reoperation for achalasia is feasible and safe with complication rates comparable to the primary laparoscopic operation. It is recommended that laparoscopic reoperative Heller's myotomy should only be performed by surgeons with special interest in oesophagogastric surgery and adequate experience in laparoscopic surgery for achalasia.

Indocyanine green fluorescence image processing techniques for breast cancer macroscopic demarcation.

Re-operation due to disease being inadvertently close to the resection margin is a major challenge in breast conserving surgery (BCS). Indocyanine green (ICG) fluorescence imaging could be used to visualize the tumor boundaries and help surgeons resect disease more efficiently. In this work, ICG fluorescence and color images were acquired with a custom-built camera system from 40 patients treated with BCS. Images were acquired from the tumor in-situ, surgical cavity post-excision, freshly excised tumor and histopathology tumour grossing. Fluorescence image intensity and texture were used as individual or combined predictors in both logistic regression (LR) and support vector machine models to predict the tumor extent. ICG fluorescence spectra in formalin-fixed histopathology grossing tumor were acquired and analyzed. Our results showed that ICG remains in the tissue after formalin fixation. Therefore, tissue imaging could be validated in freshly excised and in formalin-fixed grossing tumor. The trained LR model with combined fluorescence intensity (pixel values) and texture (slope of power spectral density curve) identified the tumor's extent in the grossing images with pixel-level resolution and sensitivity, specificity of 0.75 ± 0.3, 0.89 ± 0.2.This model was applied on tumor in-situ and surgical cavity (post-excision) images to predict tumor presence.

Global metabolic phenotyping in an experimental laparotomy model of surgical trauma.

Surgical trauma initiates a complex series of metabolic host responses designed to maintain homeostasis and ensure survival. (1)H NMR spectroscopy was applied to intraoperative urine and plasma samples as part of a strategy to analyze the metabolic response of Wistar rats to a laparotomy model. Spectral data were analyzed by multivariate statistical analysis. Principal component analysis (PCA) confirmed that surgical injury is responsible for the majority of the metabolic variability demonstrated between animals (R² Urine = 81.2% R² plasma = 80%). Further statistical analysis by orthogonal projection to latent structure discriminant analysis (OPLS-DA) allowed the identification of novel urinary metabolic markers of surgical trauma. Urinary levels of taurine, glucose, urea, creatine, allantoin, and trimethylamine-N-oxide (TMAO) were significantly increased after surgery whereas citrate and 2-oxoglutarate (2-OG) negatively correlated with the intraoperative state as did plasma levels of betaine and tyrosine. Plasma levels of lipoproteins such as VLDL and LDL also rose with the duration of surgery. Moreover, the microbial cometabolites 3-hydroxyphenylpropionate, phenylacetylglycine, and hippurate correlated with the surgical insult, indicating that the gut microbiota are highly sensitive to the global homeostatic state of the host. Metabonomic profiling provides a global overview of surgical trauma that has the potential to provide novel biomarkers for personalized surgical optimization and outcome prediction.

Assessment of the cerebral cortex during motor task behaviours in adults: a systematic review of functional near infrared spectroscopy (fNIRS) studies.

Functional near infrared spectroscopy (fNIRS) is an emerging tool for non-invasively monitoring the haemodynamic response to brain activation. The technique has been widely adopted to investigate cortical responses during motor tasks in health and disease. This systematic review provides a critical analysis of the research findings in the hope of summating relevant information, identifying consistent outcomes acquired using different spectrometers, clarifying data inconsistencies, and learning from the common challenges across disciplines. The spatiotemporal characteristics, reliability, repeatability and modulation of typical cortical response evoked by motor stimulation are all evaluated in detail. The review assesses the contribution of the technique to advancing our understanding of motor skill learning and control in the context of tasks of everyday living, athletic performance, and recovery from neurological illness. Finally, the limitations of current fNIRS technologies are examined and a series of recommendations for future studies are provided based upon the reviewed literature.

Skills training after night shift work enables acquisition of endovascular technical skills on a virtual reality simulator.

BACKGROUND: Adoption of residents' working time restrictions potentially undermines surgical training by reduction of operating room exposure. Simulation has been proposed as a way to acquire necessary skills in a laboratory environment but remains difficult to incorporate into training schedules. This study assessed whether residents working successive nights could acquire endovascular skills similar to colleagues working day shifts. METHODS: This prospective observational cohort study recruited 20 junior residents, divided into day shift and night shift groups by their respective call schedule. After initial cognitive skills training, a validated renal artery stent module on an endovascular simulator was completed over a series of seven sequential shifts during 1 week. The primary outcome measure was serial technical skill assessments. Secondary measures comprised assessments of activity, cognitive performance, introspective fatigue, quality, and quantity of preceding sleep. RESULTS: Both groups demonstrated significant learning curves for total time at the first session median vs seventh session median (181 vs 564 seconds [P < .001]; night, 1399 vs 572 [P < .001]), fluoroscopy time (day, 702 vs 308 seconds, [P < .001]; night, 669 vs 313 [P < .001]), and contrast volume (day, 29 vs 13 mL [P < .001]; night, 40 vs 16 [P < .001]). Residents working day shifts reached plateau 1 day earlier in the above measures vs those on night duty. The night shift group walked more steps (P < .001), reviewed more patients (P < .001), performed worse on all cognitive assessments (P < .05), slept less (P < .05), had poorer quality of sleep (P = .001), and was more fatigued (P < .001) than the day shift group. Acquired skill was retained a week after completion of shifts. CONCLUSION: Technical skills training after night shift work enables acquisition of endovascular technical skills, although it takes longer than after day shift training. This study provides evidence for program directors to organize simulation-based training schedules for residents on night shift rotations.

The volume-outcome relationship for radical cystectomy in England: an analysis of outcomes other than mortality.

OBJECTIVE: •To evaluate the volume-outcome relationship for radical cystectomy in England using outcomes other than mortality. PATIENTS AND METHODS: •Patients undergoing an elective radical cystectomy were extracted from administrative hospital data for financial years 2000/1 to 2006/7. •Institutional and surgeon volume was assessed against postoperative re-intervention, postoperative complications and emergency readmission within 28 days, using a set of models accounting for patient case-mix, the 'clustered' nature of the data and structural and process of care measures. RESULTS: •In the final model, the odds of re-intervention within 14 and 30 days of operation for medium-volume institutions compared to low-volume institutions were found to be 63% (odds ratio, OR, 1.63; 95% CI 1.15-2.32; P= 0.01) and 52% (OR, 1.52; 95% CI, 1.13-2.04; P= 0.01) higher, respectively. •In the summary of adjusted probabilities, low-volume institutions appeared to have a lower re-intervention rate than both medium- and high-volume institutions. •By contrast, high-volume surgeons were associated with a reduced odds (OR, 0.68; 95% CI, 0.51-0.91; P= 0.01) of early re-intervention (within 14 days) compared to low-volume surgeons. •This surgeon volume-outcome effect became apparent only after adjusting for the influence of the institution and structural and process of care confounders. •There was no statistically significant relationship between volume and complication or readmission rates. CONCLUSIONS: •Radical cystectomy measures of re-intervention rates can be used as outcome measures to discern differences across institutional or surgeon volume providers when the institutional and surgeon volume are co-examined and adjustment for structural and process of care confounders is performed. •The finding of a lower risk of re-intervention in low-volume institutions needs to be explored further.