Re-Validating the Observational Teamwork Assessment for Surgery Tool (OTAS-D): Cultural Adaptation, Refinement, and Psychometric Evaluation

Background

The nontechnical and team skills of surgical teams are critical for safety and efficiency in the operating room. Assessment of nontechnical and team skills can facilitate improvement by encouraging both self-reflection and team reflection, identifying training needs, and informing operating room (OR) team training approaches. The observational teamwork assessment for surgery (OTAS) tool is a well-validated and robust tool for capturing teamwork in the operating room. The aims of the present study were to systematically adapt and refine the OTAS for German-speaking OR staff and to test the adapted assessment tool (OTAS-D) for psychometric properties and metric equivalence.

Methods

The study was carried out in three stages: at stage 1, OTAS was translated into German. At stage 2, experienced German OR experts (surgeons, OR nurses, anesthetists) were interviewed. At stage 3, two blinded assessors observed 11 general surgical operations (general surgical and vascular procedures) and interrater reliability was tested for refined OTAS-D behavioral exemplars and scorings.

Results

The German OR experts confirmed the applicability and content validity of the vast majority of translated behavioral exemplars. After their evaluation, 32 items were changed slightly, six were changed substantially, and one item was added. During observations, perfect and substantial interobserver agreement was found for 77 behavioral exemplars (67.1 % of the items, kappa coefficient >0.60). Rating at all OTAS behaviors showed acceptable levels of reliability (intraclass correlation coefficients >0.72).

Conclusions

The OTAS-D is a tool for valid and reliable assessment of nontechnical skills that contribute to safe and effective surgical performance in ORs staffed by German-speaking professionals. Furthermore, our study serves as an example for systematically adapting and customizing well-established observational tools across different healthcare environments.     

Immunopathogenesis of abdominal sepsis

Background

Sepsis is an unsolved problem worldwide, with a 30–50 % mortality rate. The recent failures of anti-TLR4, recombinant activated protein C, and anti-TNF in clinical trials indicate a need to rethink our current understanding of sepsis’s pathophysiology. While the initial immune response is crucial for effective clearance of invading pathogens, an overly exuberant host response to infection can cause septic shock, tissue damage, and death. Profuse inflammation in sepsis is frequently followed by global immunosuppression that increases susceptibility to viral and bacterial infections. Despite the dangers of immune over-response, the immune system’s anti-inflammatory activities are likely necessary to reduce the initial over-activation of the immune system.

Purpose

With this review, we want to illuminate the different aspects of immune response to sepsis and provide insight to the ongoing difficulties currently present within sepsis research.

Conclusion

Future treatment strategies for sepsis should focus on maintaining balance between pro- and anti-inflammatory immune actions in a timely manner.     

Expanding the spectrum of PTH1R mutations in patients with primary failure of tooth eruption

Objectives

Primary failure of tooth eruption (PFE) is a rare autosomal-dominant disease characterized by severe lateral open bite as a consequence of incomplete eruption of posterior teeth. Heterozygous mutations in the parathyroid hormone 1 receptor (PTH1R) gene have been shown to cause PFE likely due to protein haploinsufficiency. To further expand on the mutational spectrum of PFE-associated mutations, we report here on the sequencing results of the PTH1R gene in 70 index PFE cases.

Materials and methods

Sanger sequencing of the PTH1R coding exons and their immediate flanking intronic sequences was performed with DNA samples from 70 index PFE cases.

Results

We identified a total of 30 unique variants, of which 12 were classified as pathogenic based on their deleterious consequences on PTH1R protein while 16 changes were characterized as unclassified variants with as yet unknown effects on disease pathology. The remaining two variants represent common polymorphisms.

Conclusions

Our data significantly increase the number of presently known unique PFE-causing PTH1R mutations and provide a series of variants with unclear pathogenicity which will require further in vitro assaying to determine their effects on protein structure and function.

Clinical relevance

Management of PTH1R-associated PFE is problematic, in particular when teeth are exposed to orthodontic force. Therefore, upon clinical suspicion of PFE, molecular DNA testing is indicated to support decision making for further treatment options.     

Biochemical analysis of the articular disc of the temporomandibular joint with magnetic resonance T2 mapping: a feasibility study

Objectives

Symptoms of temporomandibular joint (TMJ) dysfunction can seriously compromise patients' quality of life. The aim of our study was to use magnetic resonance imaging (MRI) T2 mapping of the articular disc to determine whether T2 mapping of the TMJ disc is feasible in routine clinical imaging and to assess the normal T2 relaxation time distribution within the TMJ.

Methods

Included were ten asymptomatic volunteers without pain, any mouth-opening limitations, or any clicking phenomena. MR imaging was performed on a 3-T MR scanner using a flexible, dedicated, eight-channel multielement coil. T2 mapping was performed in the oblique sagittal plane. The regions of interest (ROIs) for the T2 relaxation time maps of the disc were selected manually.

Results

The mean values for ROIs ranged between 22.4 and 28.8 ms, and the mean for all ROIs was 26.0?±?5.0 ms. Intraclass correlation (ICC) for interobserver variability was 0.698, and ICC for intraobserver variability was 0.861. There was no statistically significant difference between raters (p?=?0.091) or sides (p?=?0.810).

Conclusion

The T2 mapping technique enables ultrastructural analysis of the composition of TMJ disc. This biochemical technique is feasible in vivo, as shown in our study, when a high-field (3 T) MR and a dedicated TMJ coil are used.

Clinical relevance

T2 mapping as a biochemical technique, together with morphological MRI, may help to gain more insights into the physiology and into the pathophysiology of the articular disc in the TMJ noninvasively and in vivo.     

Small-scale universality in fluid turbulence

Turbulent flows in nature and technology possess a range of scales. The largest scales carry the memory of the physical system in which a flow is embedded. One challenge is to unravel the universal statistical properties that all turbulent flows share despite their different large-scale driving mechanisms or their particular flow geometries. In the present work, we study three turbulent flows of systematically increasing complexity. These are homogeneous and isotropic turbulence in a periodic box, turbulent shear flow between two parallel walls, and thermal convection in a closed cylindrical container. They are computed by highly resolved direct numerical simulations of the governing dynamical equations. We use these simulation data to establish two fundamental results: (i) at Reynolds numbers Re ∼ 10² the fluctuations of the velocity derivatives pass through a transition from nearly Gaussian (or slightly sub-Gaussian) to intermittent behavior that is characteristic of fully developed high Reynolds number turbulence, and (ii) beyond the transition point, the statistics of the rate of energy dissipation in all three flows obey the same Reynolds number power laws derived for homogeneous turbulence. These results allow us to claim universality of small scales even at low Reynolds numbers. Our results shed new light on the notion of when the turbulence is fully developed at the small scales without relying on the existence of an extended inertial range.An enduring notion in the phenomenology of turbulence is the universality of small scales. It has been taken for granted in theoretical approaches (e.g., refs. 1–8) and analyzed in numerical simulations (9–11) as well as various laboratory experiments (e.g., refs. 5 and 12). The standard paradigm is that whereas the large scales are nonuniversal, reflecting the circumstances of their generation, an increasingly weaker degree of nonuniversality is imparted to small scales with increasing separation between the large and small scales. This scale separation is thought to increase with the flow Reynolds number, so a proper test of universality has been thought to require very high Reynolds numbers. Consequently, many substantial efforts have been made to produce such high-Reynolds-number flows (e.g., ref. 12).Here, we show evidence for an alternative point of view: If one resolves small scales accurately, one observes, even at low Reynolds numbers, universal scaling of velocity gradients that manifest primarily at small scales. We stress that small-scale dynamics are strongly nonlinear even in low-Reynolds-number flows driven by large-scale forcing. There is thus considerable merit in measuring or simulating low-Reynolds-number flows much more accurately than has been the practice and exploring the evidence for universality (or lack thereof), instead of advancing as inevitable the notion that useful lessons about universality are possible only at very high Reynolds numbers. Indeed, another result of this paper is that there exists a threshold Reynolds number above which Gaussian-like fluctuations tend to assume intermittent characteristics of fully developed flows and that these features can be extracted by accessing increasingly smaller scales even if the Reynolds numbers are quite moderate. The latter result is especially important for purposes of identifying a fixed point in certain renormalization group expansion procedures (8).     

Plain Radiographs Fail to Reflect Femoral Offset in Total Hip Arthroplasty

Successful biomechanical reconstruction is a major goal in total hip arthroplasty (THA). We measured leg length (LL), global (GO) and femoral offset (FO) change on anteroposterior pelvis radiographs and on three-dimensional computed-tomography (3D-CT) with fiducial landmarks after cementless THA on 18 hips of cadaveric specimens. Measurements on radiographs were performed twice by four examiners and showed high interobserver (mean CCC ≥ 0.79) and intraobserver agreements (mean ICC ≥ 0.88). Mean differences between radiographic and 3D-CT measurements were 1.0 (SD 2.0) mm for LL, 0.6 (SD 3.6) mm for GO and 1.4 (SD 5.2) mm for FO. 1% of radiographic LL-, 15% of GO- and 35% of FO measurements were outside a tolerance limit of 5 mm. Radiographs seem acceptable for measuring LL/GO change but fail to reflect FO change in THA.