[Practice Guidelines for Central Venous Access 2020 - Time for German Guidelines]. / Amerikanische Praxis-Leitlinie für den zentralen Venenzugang aus dem Jahr 2020.

The American Society of Anesthesiologists released practice guidelines for central venous access in 2020, and the entire world literature was examined for evidence on how to perform the entire process with best practice and minimal risk and harm to the patient. These guidelines may serve as a gold standard for individual procedural steps, allowing practitioners and hospital departments to critically question the own standard and improve upon them.We interpreted the guidelines for individual procedural steps on how to improve success of catheterization, minimize risks or adverse effects, enhance the management of accidental arterial punctures, adhere to evidence-based practices, and generally reduce the trauma of puncturing. In our opinion, the most needed recommendation for central venous access is to utilize ultrasound guidance, a practice that many international societies have already incorporated into their published national guidelines.In our view, it is time to implement a national guideline for central venous access using ultrasound in Germany. Doing so may improve success rates in the first attempt, reduce procedural time, decrease the number of needle insertions per patient, and lower the rate of arterial punctures. This approach represents best practice from ethical, insurance, civil rights, and patient security perspectives, and is supported by relevant societies.

Next step trauma and orthopaedic surgery: integration of augmented reality for reduction and nail implantation of tibial fractures.

INTRODUCTION: There is a tremendous scope of hardware and software development going on in augmented reality (AR), also in trauma and orthopaedic surgery. However, there are only a few systems available for intra-operative 3D imaging and guidance, most of them rely on peri- and intra-operative X-ray imaging. Especially in complex situations such as pelvic surgery or multifragmentary multilevel fractures, intra-operative 3D imaging and implant tracking systems have proven to be of great advantage for the outcome of the surgery and can help reduce X-ray exposure, at least for the surgical team (Ochs et al. in Injury 41:1297 1305, 2010). Yet, the current systems do not provide the ability to have a dynamic live view from the perspective of the surgeon. Our study describes a prototype AR-based system for live tracking which does not rely on X-rays. MATERIALS AND METHODS: A protype live-view intra-operative guidance system using an AR head-mounted device (HMD) was developed and tested on the implantation of a medullary nail in a tibia fracture model. Software algorithms that allow live view and tracking of the implant, fracture fragments and soft tissue without the intra-operative use of X-rays were derived. RESULTS: The implantation of a medullar tibia nail is possible while only relying on AR-guidance and live view without the intra-operative use of X-rays. CONCLUSIONS: The current paper describes a feasibility study with a prototype of an intra-operative dynamic live tracking and imaging system that does not require intra-operative use of X-rays and dynamically adjust to the perspective of the surgeons due to an AR HMD. To our knowledge, the current literature does not describe any similar systems. This could be the next step in surgical imaging and education and a promising way to improve patient care.

Minimally invasive arthroscopy of the knee using a new 2 mm device.

Arthroscopy has been evolving over the last decades, whereas arthroscopic devices have not changed much. Smaller diameter arthroscopes would potentially reduce the intraoperative trauma for cartilage and soft tissues. Two-millimeter-diameter arthroscopy demonstrated very good visualization and reach of intraarticular structures-similar to knee arthroscopy using a standard arthroscopic system.

[Lung Ultrasound for Anesthesia, Intensive Care and Emergency Medicine]. / Lungensonografie für Anästhesie, Intensiv- und Notfallmedizin.

Lung ultrasound is an underrated tool in preclinical emergency situations, intensive care units, ORs and emergency rooms. For certain clinical questions, there is a drastically higher sensitivity in comparison to chest X-ray examinations (sensitivity in pneumothorax diagnostics 86 vs. 28%, specificity 97 vs. 100%. A standardized examination improves the quality of the ultrasound examination and thus the diagnostic value. The article provides basic information on pulmonary ultrasound and aims to highlight the superiority of ultrasound over x-ray procedures for anesthesia, intensive care and emergency medicine in accordance to the international evidence-based recommendations for point of care ultrasound. Finally, we added a checklist for the "post-interventional exclusion of pneumothorax" and a checklist for the "diagnosis of dyspnea by sonography".

Quantification of the vasodilatory effect of axillary plexus block. A prospective controlled study.

BACKGROUND: Axillary plexus block is a common method for regional anesthesia, especially in hand and wrist surgery. Local anesthetics (e.g., mepivacaine) are injected around the peripheral nerves in the axilla. A vasodilatory effect due to sympathicolysis has been described, but not quantified. MATERIALS AND METHODS: In a prospective controlled study between October 2012 and July 2013, we analyzed 20 patients with saddle joint arthritis undergoing trapeziectomy under axillary plexus block. Patients received a mixture of mepivacaine 1% and ropivacaine 0.75% in a 3:1 ratio. The measurements were carried out on the plexus side and the contralateral hand, which acted as the control. Laser-Doppler spectrophotometry (oxygen to see [O2C] device) was used to measure various perfusion factors before and after the plexus block, after surgery and in 2-h intervals until 6 h postoperatively. RESULTS: Compared with the contralateral side, the plexus block produced an enhancement of tissue oxygen saturation of 117.35 ± 34.99% (cf. control SO2: 92.92 ± 22.30%, P < 0.010) of the baseline value. Furthermore, blood filling of microvessels (rHb: 131.36 ± 48.64% versus 109.12 ± 33.25%, P < 0.0062), peripheral blood flow (219.85 ± 165.59% versus 129.55 ± 77.12%, P < 0.018), and velocity (163.86 ± 58.18% versus 117.16 ± 45.05%, P < 0.006) showed an increase of values. CONCLUSIONS: Axillary plexus block produces an improvement of peripheral tissue oxygen saturation of the upper extremity over the first 4 h after the inception of anesthesia.

Phrenic nerve block caused by interscalene brachial plexus block: breathing effects of different sites of injection.

BACKGROUND: Interscalene brachial plexus (ISB) block is often associated with phrenic nerve block and diaphragmatic paresis. The goal of our study was to test if the anterior or the posterior ultrasound guided approach of the ISB is associated with a lower incidence of phrenic nerve blocks and impaired lung function. METHODS: This was a prospective, randomized and single-blinded study of 84 patients scheduled for elective shoulder surgery who fullfilled the inclusion and exclusion critereria. Patients were randomized in two groups to receive either the anterior (n = 42) or the posterior (n = 42) approach for ISB. Clinical data were recorded. In both groups patients received ISB with a total injection volume of 15 ml of ropivacaine 1 %. Spirometry was conducted at baseline (T0) and 30 min (T30) after accomplishing the block. Changes in spirometrical variables between T0 and T30 were investigated by Wilcoxon signed-rank test for each puncture approach. The temporal difference between the posterior and the anterior puncture approach groups were again analyzed by the Wilcoxon-Mann-Whitney test. RESULTS: The spirometric results showed a significant decrease in vital capacity, forced expiratory volume per second, and maximum nasal inspiratory breathing after the Interscalene brachial plexus block; indicating a phrenic nerve block (p <0.001, Wilcoxon signed-rank). A significant difference in the development of the spirometric parameters between the anterior and the posterior group could not be identified (Wilcoxon-Mann-Whitney test). Despite the changes in spirometry, no cases of dyspnea were reported. CONCLUSION: A different site of injection (anterior or posterior) did not show an effect in reducing the cervical block spread of the local anesthetic and the incidence of phrenic nerve blocks during during ultrasound guided Interscalene brachial plexus block. Clinical breathing effects of phrenic nerve blocks are, however, usually well compensated, and subjective dyspnea did not occur in our patients. TRIAL REGISTRATION: German Clinical Trials Register (DRKS number 00009908 , registered 26 January 2016).