Citations

Purpose To determine whether “chronometric pressure” (i.e., a verbal prompt to increase speed) could predictably alter medical learners’ speed–accuracy trade-off during a simulated surgical task, thus modifying the challenge. Method The authors performed a single-task, interrupted time-series study, enrolling surgery residents and medical students from two institutions in September and October 2015. Participants completed 10 repetitions of a simulated blood vessel ligation (placement of two ligatures 1 cm apart). Between repetitions 5 and 6, participants were verbally encouraged to complete the next repetition 20% faster than the previous one. Outcomes included time and accuracy (ligature tightness, placement distance). Data were analyzed using random-coefficients spline models. Results The authors analyzed data from 78 participants (25 medical students, 16 first-year residents, 37 senior [second-year or higher] residents). Overall, time decreased from the 1st (mean [standard deviation] 39.8 seconds [18.4]) to the 10th (29.6 [12.5]) repetition. The spline model showed a decrease in time between repetitions 5 and 6 of 8.6 seconds (95% confidence interval: −11.1, −6.1). The faster time corresponded with declines in ligature tightness (unadjusted difference −19%; decrease in odds 0.86 [0.76, 0.98]) and placement accuracy (unadjusted difference −5%; decrease in odds 0.86 [0.75, 0.99]). Significant differences in the speed–accuracy trade-off were seen by training level, with senior residents demonstrating the greatest decline in accuracy as speed increased. Conclusions Chronometric pressure influenced the speed–accuracy trade-off and modified the challenge level in a simulated surgical task. It may help unmask correctable deficiencies or false plateaus in learners’ skill development.

Background: Bone loss in shoulder instability is a well-recognized cause of failure after stabilization surgery. Many approaches have been described to address glenoid bone loss, including coracoid transfer. This transfer can be technically difficult and has been associated with high complication rates. An ideal alternative to coracoid transfer would be an autologous source of fresh osteochondral graft with enough surface area to replace significant glenoid bone loss. The distal clavicle potentially provides such a graft source that is readily available and low-cost. Purpose: To evaluate distal clavicular autograft reconstruction for instability-related glenoid bone loss, specifically comparing the width of the clavicular autograft with the width of an ipsilateral coracoid graft as prepared for a Latarjet procedure. Further, we sought to compare the articular cartilage thickness of the distal clavicle graft with that of the native glenoid. Study Design: Controlled laboratory study. Methods: Twenty-seven fresh-frozen cadaver specimens were dissected, and an open distal clavicle excision was performed. The coracoid process in each specimen was prepared as has been described for a classic Latarjet coracoid transfer. In each specimen, the distal clavicle graft was compared with the coracoid graft for size and potential of glenoid articular radius of restoration. The distal clavicle graft was also compared with the native glenoid for cartilage thickness. Results: In all specimens, the distal clavicle grafts provided a greater radius of glenoid restoration than the coracoid grafts ( P < .0001). On average, the clavicular graft was able to reconstruct 44% of the glenoid diameter, compared with 33% for the coracoid graft ( P < .0001). The articular cartilage of the glenoid was significantly thicker (1.4 mm thicker, P < .0001) than that of the distal clavicular autograft (average ± SD, 3.5 ± 0.6 mm vs 2.1 ± 0.8 mm, respectively). When specimens with osteoarthritis were excluded, this difference decreased to 0.97 mm when compared with the clavicular cartilage ( P = .0026). Conclusion: The distal clavicle autograft can restore a significantly greater glenoid bone deficit than the Latarjet procedure and has the additional benefit of restoring articular cartilage to the glenoid. The articular cartilage thickness of the distal clavicle is within 1.4 mm of that of the native glenoid. Clinical Relevance: The distal clavicular autograft may be a suitable option for reconstruction of instability-related glenoid bone loss. This graft provides a structural osteochondral autograft with a broader radius of reconstruction than that of a coracoid graft, is locally available, has minimal donor site morbidity, is anatomic, and provides articular cartilage.

Background: Glenoid bone loss is a well-accepted risk factor for failure after arthroscopic stabilization of anterior glenohumeral instability. Glenoid bone loss in posterior instability has been noted relative to its existence in posterior instability surgery. Its effect on outcomes after arthroscopic stabilization has not been specifically evaluated and reported. Purpose: The purpose was to evaluate the presence of posterior glenoid bone loss in a series of patients who had undergone arthroscopic isolated stabilization of the posterior labrum. Bone loss was then correlated to return-to-duty rates, complications, and validated patient-reported outcomes. Study Design: Case-control study; Level of evidence, 3. Methods: A retrospective review was conducted at a single military treatment facility over a 4-year period (2010-2013). Patients with primary posterior instability who underwent arthroscopic isolated posterior labral repair were included. Preoperative magnetic resonance imaging was used to calculate posterior glenoid bone loss using a standardized “perfect circle” technique. Demographics, return to duty, complications, and reoperations, as well as outcomes scores including the Single Assessment Numeric Evaluation and the Western Ontario Shoulder Instability Index (WOSI) scores, were obtained. Outcomes were analyzed across all patients based on percentage of posterior glenoid bone loss. Bone loss was then categorized as below or above the subcritical threshold of 13.5% to determine if bone loss effected outcomes similar to what has been shown in anterior instability. Results: There were 43 consecutive patients with primary, isolated posterior instability, and 32 (74.4%) completed WOSI scoring. Mean follow-up was 53.7 months (range, 25-82 months) The mean posterior glenoid bone loss was 7.3% (0%-21.5%). Ten of 32 patients (31%) had no appreciable bone loss. Bone loss exceeded 13.5% in 7 of 32 patients (22%), and 2 patients (6%) exceeded 20% bone loss. Return to full duty or activity was nearly 90% overall. However, those with >13.5%, subcritical glenoid bone loss, were statistically less likely to return to full duty (relative risk = 1.8), but outcomes scores, complications, and revision rates were otherwise not different in those with no or minimal bone loss versus those with more significant amounts. Conclusion: Posterior glenoid bone loss has not previously been evaluated independently relative to patients with shoulder instability repairs. Sixty-nine percent of our patients had measurable bone loss, and 22% had greater than 13.5%, or above subcritical bone loss. While these patients were statistically less likely to return to full duty, the reoperation rate, complications, and patient-reported outcomes between groups were not different.

The control of epithelial cell proliferation, differentiation, and apoptosis requires a balance between signaling and transcriptional regulation. Recent developments in pancreatic cell research have revealed that transforming growth factor-β (TGF-β) signaling is important for the regulation of each of these phenomena. More importantly, perturbations in this pathway are associated with pancreatic cancer. A chief example of these alterations is the mutation in the TGF-β-regulated transcription factor Smad4/DPC4 that is found in a large percentage of pancreatic tumors. Surprisingly, studies on transcription factors have remained an underrepresented area of pancreatic research. However, the discovery of Smad4/DPC4 as a transcription factor fueled further studies aimed at characterizing transcription factors involved in normal and neoplastic pancreatic cell growth. Our laboratory recently described the existence of a novel family of zinc finger transcription factors, TGF-β-inducible early-response gene (TIEG)1 and TIEG2, from the exocrine pancreas that, similarly to Smads, participate in the TGF-β response and inhibit epithelial cell proliferation. This review therefore focuses on describing the structure and function of these two families of transcription factor proteins that are becoming key players in the regulation of pancreatic cell growth.

Accumulation of collagen produces organ dysfunction in many pathological conditions. We measured the fractional synthesis rate (FSR) of dermal collagen in five human volunteers from the increment of [13C]proline in detergent-soluble dermal collagen hydroxylated to hydroxyproline during a continuous infusion ofl-[1-13C]proline. In these and eight other volunteers, we measured [13C]proline enrichment in skin aminoacyl-tRNA, skin tissue fluid amino acid, and plasma. The prolyl-[13C]tRNA enrichment was one-half that in tissue fluid proline and more than threefold less than in plasma. The FSR of dermal collagen was 0.076 ± 0.063%/h (mean ± SD), similar to previously reported rates for skeletal muscle contractile proteins and substantially slower than hepatically derived circulating proteins such as albumin or fibrinogen. We conclude that the FSR of human dermal collagen resembles that of other human proteins considered to display slow turnover. The current method for its measurement may be used to determine the regulation of collagen synthesis in other organs and disease states.

Introduction Clinical practice guidelines facilitate optimal clinical practice. Point of care access, interpretation and application of such guidelines, however, is inconsistent. Informatics-based tools may help clinicians apply guidelines more consistently. We have developed a novel clinical decision support tool that presents guideline-relevant information and actionable items to clinicians at the point of care. We aim to test whether this tool improves the management of hyperlipidaemia, atrial fibrillation and heart failure by primary care clinicians. Methods/analysis Clinician care teams were cluster randomised to receive access to the clinical decision support tool or passive access to institutional guidelines on 16 May 2016. The trial began on 1 June 2016 when access to the tool was granted to the intervention clinicians. The trial will be run for 6 months to ensure a sufficient number of patient encounters to achieve 80% power to detect a twofold increase in the primary outcome at the 0.05 level of significance. The primary outcome measure will be the percentage of guideline-based recommendations acted on by clinicians for hyperlipidaemia, atrial fibrillation and heart failure. We hypothesise care teams with access to the clinical decision support tool will act on recommendations at a higher rate than care teams in the standard of care arm. Ethics and dissemination The Mayo Clinic Institutional Review Board approved all study procedures. Informed consent was obtained from clinicians. A waiver of informed consent and of Health Insurance Portability and Accountability Act (HIPAA) authorisation for patients managed by clinicians in the study was granted. In addition to publication, results will be disseminated via meetings and newsletters. Trial registration number NCT02742545 .

SummaryObjectiveThe multicenter National Infantile Spasms Consortium prospective cohort was used to compare outcomes and phenotypic features of patients with infantile spasms with and without hypsarrhythmia.MethodsPatients aged 2 months to 2 years were enrolled prospectively with new‐onset infantile spasms. Treatment choice and categorization of hypsarrhythmia were determined clinically at each site. Response to therapy was defined as resolution of clinical spasms (and hypsarrhythmia if present) without relapse 3 months after initiation.ResultsEighty‐two percent of patients had hypsarrhythmia, but this was not associated with gender, mean age, preexisting developmental delay or epilepsy, etiology, or response to first‐line therapy. Infants with hypsarrhythmia were more likely to receive standard treatment (adrenocorticotropic hormone, prednisolone, or vigabatrin [odds ratio (OR) 2.6, 95% confidence interval (CI) 1.4–4.7] and preexisting epilepsy reduced the likelihood of standard treatment (OR3.2, 95%CI1.9–5.4). Hypsarrhythmia was not a determinant of response to treatment. A logistic regression model demonstrated that later age of onset (OR1.09 per month, 95%CI1.03–1.15) and absence of preexisting epilepsy (OR1.7, 95%CI1.06–2.81) had a small impact on the likelihood of responding to the first‐line treatment. However, receiving standard first‐line treatment increased the likelihood of responding dramatically: vigabatrin (OR5.2 ,95%CI2–13.7), prednisolone (OR8, 95%CI3.1–20.6), and adrenocorticotropic hormone (ACTH;OR10.2, 95%CI4.1–25.8) .SignificanceFirst‐line treatment with standard therapy was by far the most important variable in determining likelihood of response to treatment of infantile spasms with or without hypsarrhythmia.

Purpose Compare the effect of personalized feedback (PF) vs. task demonstration (TD), both delivered via video, on laparoscopic knot-tying skills and perceived workload; and evaluate the effect of repeated practice. Method General surgery interns and research fellows completed four repetitions of a simulated laparoscopic knot-tying task at one-month intervals. Midway between repetitions, participants received via e-mail either a TD video (demonstration by an expert) or a PF video (video of their own performance with voiceover from a blinded senior surgeon). Each participant received at least one video per format, with sequence randomly assigned. Outcomes included performance scores and NASA Task Load Index (NASA-TLX) scores. To evaluate the effectiveness of repeated practice, scores from these trainees on a separate delayed retention test were compared against historical controls who did not have scheduled repetitions. Results Twenty-one trainees completed the randomized study. Mean change in performance scores was significantly greater for those receiving PF (difference = 23.1 of 150 [95% confidence interval (CI): 0, 46.2], P = .05). Perceived workload was also significantly reduced (difference = −3.0 of 20 [95% CI: −5.8, −0.3], P = .04). Compared with historical controls (N = 93), the 21 with scheduled repeated practice had higher scores on the laparoscopic knot-tying assessment two weeks after the final repetition (difference = 1.5 of 10 [95% CI: 0.2, 2.8], P = .02). Conclusions Personalized video feedback improves trainees’ procedural performance and perceived workload compared with a task demonstration video. Brief monthly practice sessions support skill acquisition and retention.

Objective: The European Guidelines Meeting on Laparoscopic Liver Surgery was held in Southampton on February 10 and 11, 2017 with the aim of presenting and validating clinical practice guidelines for laparoscopic liver surgery. Background: The exponential growth of laparoscopic liver surgery in recent years mandates the development of clinical practice guidelines to direct the speciality's continued safe progression and dissemination. Methods: A unique approach to the development of clinical guidelines was adopted. Three well-validated methods were integrated: the Scottish Intercollegiate Guidelines Network methodology for the assessment of evidence and development of guideline statements; the Delphi method of establishing expert consensus, and the AGREE II-GRS Instrument for the assessment of the methodological quality and external validation of the final statements. Results: Along with the committee chairman, 22 European experts; 7 junior experts and an independent validation committee of 11 international surgeons produced 67 guideline statements for the safe progression and dissemination of laparoscopic liver surgery. Each of the statements reached at least a 95% consensus among the experts and were endorsed by the independent validation committee. Conclusion: The European Guidelines Meeting for Laparoscopic Liver Surgery has produced a set of clinical practice guidelines that have been independently validated for the safe development and progression of laparoscopic liver surgery. The Southampton Guidelines have amalgamated the available evidence and a wealth of experts’ knowledge taking in consideration the relevant stakeholders’ opinions and complying with the international methodology standards.