[Lung ultrasound in COVID-19]. / Lungensonographie bei COVID­19.

Providing medical care to patients suffering from the coronavirus disease 2019 (COVID-19) pandemic is a major challenge for government healthcare systems around the world. The new coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), shows a high organ specificity for the lower respiratory tract. Since there is so far no effective treatment or vaccination against the virus, early diagnostic recognition is of great importance. Due to the specific aspects of the infection, which mainly begins in the peripheral lung parenchyma, lung ultrasonography is suitable as a diagnostic imaging method to identify suspected cases as such in the early stages of the disease. Serial ultrasound examinations on patients with confirmed COVID-19 can promptly detect changes in the affected lung tissue at the bedside. This article summarizes the diagnostic potential of lung ultrasound with respect to screening and therapeutic decision-making in patients with suspected or confirmed SARS-CoV­2 pneumonia.

[Sonographic diagnostics in operative intensive care medicine : Pericardial hematoma after cardiac surgery]. / Sonographische Diagnostik in der operativen Intensivmedizin : Perikardhämatom nach kardiochirurgischen Eingriffen.

These two case reports describe the use of transthoracic echocardiography in cardiac surgery patients during postoperative intensive care, when a pericardial hematoma developed. A focused echocardiographic examination was performed, which in both cases led to the correct diagnosis and revealed the cause for hemodynamic instability. Following additional computed tomography (CT) scans, cardiac surgery was performed on one patient, while in the other, bedside sonography was used for controlled pleural puncture and drainage of the pericardial hematoma. The case reports demonstrate that intrathoracic bleeding after cardiac surgery may develop with a latency of days to weeks, which can become hemodynamically relevant and require an intervention. Bedside point of care echocardiography opens the way for securing the diagnosis by means of CT or magnetic resonance imaging (MRI) if the circulatory state of the patient allows this prior to hematoma drainage or evacuation.

[Acute perioperative right heart insufficiency : Diagnostics and treatment]. / Akute perioperative Rechtsherzinsuffizienz : Diagnostik und Therapie.

Acute right heart failure is often overlooked as a cause of cardiopulmonary insufficiency. The various pathologies underlying right heart failure at the level of afterload, preload and contractility, make rapid, targeted diagnostics necessary. In addition to clinical symptoms and laboratory chemical parameters, echocardiography in particular is relevant for making a diagnosis. Symptomatic treatment of the endangered patient is essential. The focus is on a reduction of right ventricular pressure and afterload, a correction of systemic hypotension and positive inotropic support of the right ventricle. Mechanical organ replacement and support procedures are increasingly being used in the case of persistent right heart failure and expand the possibilities for treatment. Decisive for the prognosis is a causal treatment adapted to the underlying triggering disease.

[General principles of sonography, part 2: System technology, basic techniques and artifacts]. / Allgemeine Grundlagen der Sonographie, Teil 2: Systemtechnologie, Basistechniken und Artefakte.

Since the introduction of portable ultrasound systems, sonography has become well established as an integral part of the anesthesiological and critical care equipment and of monitoring. The selection of various ultrasound transducers, sonographic techniques and imaging modes enables a broad variety of clinical applications. In depth background knowledge of the technical aspects is crucial for obtaining what a highly sophisticated ultrasound system has to offer, i.e., sonographic transparency of the complete body and valid information on the structure and dynamics of organs and the circulation.

[Emergency sonography]. / Notfallsonographie.

Emergency sonography encompasses a number of targeted sonographic investigation techniques, which allow a quick response to frequently occurring situations arising in anesthesiology, including intensive care and emergency medicine. Emergency sonography supports point of care diagnostics to clarify the possible causes of hemodynamic and respiratory instability, e.g. to determine the extent of intra-abdominal bleeding in a still compensated patient with multiple trauma and to support interventions, such as pleural fluid drainage. Important emergency sonographic techniques include focused echocardiography, as well as thoracic and abdominal ultrasound, supplemented by various other applications, e.g in the head and neck region. In comparison to conventional sonographic examination techniques, these techniques are used with reduced examination times and a focussed assessment of specific clinical problems. By means of a few standardized cross-sectional planes, numerous questions can be quickly addressed and therapeutic consequences can be deduced.

Prehospital airway management using the laryngeal tube. An emergency department point of view.

BACKGROUND: Competence in airway management and maintenance of oxygenation and ventilation represent fundamental skills in emergency medicine. The successful use of laryngeal tubes (LT, LT-D, LTS II) to secure the airway in the prehospital setting has been published in the past. However, some complications can be associated with the use of a laryngeal tube. METHODS: In a nonconsecutive case series, problems and complications associated with the use of the laryngeal tube in prehospital emergency medicine as seen by independent observers in the emergency room are presented. RESULTS: Various problems and possible complications associated with the use of a laryngeal tube in eight case reports are reported: incorrect placement of the laryngeal tube in the trachea, displacement and/or incorrect placement of the laryngeal tube in the pharynx, tongue and pharyngeal swelling with subsequently difficult laryngoscopy, and inadequate ventilation due to unrecognized airway obstruction and tension pneumothorax. CONCLUSION: Although the laryngeal tube is considered to be an effective, safe, and rapidly appropriable supraglottic airway device, it is also associated with adverse effects. In order to prevent tongue swelling, after initial prehospital or in-hospital placement of laryngeal tube and cuff inflation, it is important to adjust and monitor the cuff pressure. Article in English.

[Prediction of further hospital treatment for emergency patients by emergency medical service physicians]. / Notärztliche Einschätzung der klinischen Weiterversorgung von Notfallpatienten.

INTRODUCTION: Prehospital assessment of illness and injury severity with the National Advisory Committee for Aeronautics (NACA) score and hospital pre-arrival notification of a patient who is likely to need intensive care unit (ICU) or intermediate care unit (IMC) admission are both common in Germany's physician-staffed emergency medical services (EMS) system. AIM: This study aimed at comparing the prehospital evaluation of severity of disease or injuries by EMS physicians and the subsequent clinical treatment in unselected emergency department (ED) patients. MATERIAL AND METHODS: This study involved a prospective observational analysis of patients transported to the ED of an academic level I hospital escorted by an EMS physician over a period of 6 months (February-July 2011). The physician's qualification and the patient's NACA score were documented and the EMS physician was asked to predict whether the patient would need hospital admission and, if so, to the general ward, IMC or ICU. After the ED treatment, discharge or admission, outcome and length of hospital and ICU or IMC stay were documented. RESULTS: A total of 378 mostly non-trauma patients (88 %) treated by experienced EMS physicians could be enrolled. The number of patients discharged from the ED decreased, while the number of patients admitted to the ICU increased with higher NACA scores. Prehospital prediction of discharge or admission, IMC or ICU treatment by EMS physicians was accurate in 47 % of the patients. In 40 % of patients a lower level of care was sufficient while 12 % needed treatment on a higher level of care than that predicted by EMS physicians. Of the patients 39 % who were predicted to be discharged after ED treatment, were admitted to hospital and 48 % of patients predicted to be admitted to the IMC were admitted to the general ward. Patients predicted to be admitted to the ICU were admitted to the ICU in 75 %. Higher NACA scores were associated with increased mortality and a longer hospital IMC or ICU length of stay, but significant differences were only found between patients with NACA V versus VI scores or patients predicted to be treated on the IMC versus the ICU. CONCLUSIONS: Prehospital NACA scores indicate the need for inpatient treatment, but neither hospital discharge or admission nor need of IMC or ICU admission after initial ED treatment could be sufficiently predicted by EMS physicians. Thus, hospital prenotification in order to predispose IMC or ICU capacities does not seem to be useful in cases where an ED can reassess admitted EMS patients.

[Transesophageal echocardiography for non-cardiac surgery patients: superfluous luxury or essential diagnostic tool?]. / Transösophageale Echokardiographie bei nichtkardiochirurgischen Intensivpatienten: Uberflüssiger Luxus oder unerlässliches Diagnostikum?

BACKGROUND: The value of transesophageal echocardiography (TEE) in non-cardiac critically ill patients has barely been studied. MATERIALS AND METHODS: Over a period of 4 years TEE was used prospectively to evaluate patients with acute hemodynamic instability in non-cardiac critically ill patients in addition to standard care. RESULTS: A total of 363 TEE studies were performed in 339 selected patients. Volume depletion (169/47%) and regional wall motion abnormalities (97/27%) were the most frequent findings followed by global left ventricular dysfunction (79/22%). Of the TEE studies, 203 (56%) provided additional information with therapeutic relevance in 164 (45%) cases. CONCLUSIONS: Transesophageal echocardiography provides additional information in critically ill non-cardiac patients with unexplained hemodynamic instability. In the majority of cases a clinical diagnosis is confirmed or improvement of volume resuscitation and catecholamine therapy can be achieved. In the minority of patients the results of TEE lead to distinct changes in medical management. Whether this improved diagnostic accuracy favours outcome, still needs to be evaluated.

Ultrasound-guided arterial cannulation in infants improves success rate.

BACKGROUND AND OBJECTIVE: In small children, the placement of arterial catheters can be technically challenging for even the most experienced anaesthetist. We investigated whether ultrasound imaging would improve the success rate and reduce time demand and complications of radial artery cannulation. METHOD: In this prospective randomized study, we performed radial artery cannulation in 30 small children (age 40 +/- 33 months) using two different techniques for localization of the vessel. In Group 1 (n = 15), the traditional palpation method was used, while in Group 2 (n = 15) cannulation was directed by vascular ultrasound imaging. In addition, we used ultrasound to determine the cross-sectional area of the radial artery with and without dorsiflexion. For statistical analysis, the non-parametric U-test for non-paired data and the Wilcoxon signed rank sum test for paired data were used. Differences were considered significant, when P < 0.05. RESULTS: Ultrasound-guided puncture was successful in all children of Group 2 compared to only 12 of 15 (80%) children in Group 1. Fewer attempts with the imaging technique were required than with the traditional technique (20 vs. 34, P < 0.05). Dorsiflexion significantly reduced the mean cross-sectional area of the artery by 19%. CONCLUSION: The current pilot study suggests that ultrasound guidance is appropriate for radial artery catheter insertion, sharing many of the benefits of ultrasound-guided central vein catheter insertion.

[Modern anesthesiologic concepts supporting paranasal sinus surgery]. / Moderne Anästhesieverfahren in der endonasalen Nasennebenhöhlenchirurgie.

BACKGROUND: Optimal vision is essential for successful endonasal sinus surgery. Beside topical vasoconstriction general anaesthesia can contribute to reduce intraoperative bleeding. METHODS AND RESULTS: For many years deliberate hypotension was used to prevent intraoperative bleeding. The intentional reduction of systolic blood pressure to 50-60 mm Hg was achieved by the use of Sodium Nitroprusside alone or in combination with other vasoactive agents. However, intraoperative bleeding is not affected by this technique unless the systolic blood pressure falls below 60 mm Hg which can cause serious side effects for the patient. Recently, there is growing evidence that not only systolic blood pressure but also a low heart rate (< 60 beats per minute) can minimize surgical bleeding. With the introduction of total intravenous anaesthesia (TIVA) by the use of Propofol and Remifentanyl an anaesthetic technique has been established which fulfils the haemodynamic requirements in endonasal sinus surgery in many regards. The inhibiting effects on the cardiovascular system of these drugs alone can lead to a reduced bleeding. TIVA allows the reduction of the systolic blood pressure to 60 mm Hg as well as the heart rate below 60 beats per minute. If necessary it can be supported by vasoactive agents of which betablockers have a theoretical advantage. CONCLUSION: For general anaesthesia in endonasal sinus surgery Sodium Nitroprusside is no longer recommended. Instead a TIVA using Propofol and Remifentanil should be used.

Ultrasound-guided anaesthesia of the axillary brachial plexus: efficacy of multiple injection approach.

AIM: High resolution ultrasound is a new method for detecting anatomical structures in the axilla. The visualisation of nerves can improve the quality of nerve blocks. The aim of our study was to investigate the feasibility of hand held ultrasound to perform sonographically guided blockades of the axillary plexus. METHOD: We investigated 46 patients routinely scheduled for forearm and hand surgery (ASA physical status I-IV, age range 19 - 89 years, mean 47). The axilla was examined using a handheld ultrasound system with a 10 MHz linear array probe. The median, ulnar, radial and musculocutaneus nerve were visualised by ultrasound. Selective nerve blockade was performed under sonographic guidance. Real time monitoring of the local anaesthetic spread was performed. Time required to perform the block and onset times of anaesthesia were documented. RESULTS: Complete anaesthesia of the brachial plexus was achieved in all cases. The average time to perform the block was 5 minutes (SD 2 min). Onset time for the block was 7 minutes (SD 3 min). CONCLUSION: Performing axillary nerve blockade using ultrasound guidance provides excellent anaesthesia and fast onset times.

Sonographic imaging of the sciatic nerve division in the popliteal fossa.

BACKGROUND: We studied the anatomy of the sciatic nerve and its division into the tibial and peroneal part using handheld ultrasound in adults. We wanted to evaluate the feasibility of ultrasound-guided identification of the sciatic nerve in the popliteal fossa and the correlation of the findings by ultrasound with patients' characteristics. METHODS: 74 volunteers were randomly selected. Using a handheld ultrasound system with a 5-10 MHz linear array probe the popliteal fossa and the back of the thigh were examined and measured. Using a caliper the distance of the joint line to the nerve division was measured. The sciatic nerve and its division were depicted by ultrasound. RESULTS: We could depict the sciatic nerve in all volunteers and its division in 53 of 74 (72%) volunteers. The position of nerve division showed large anatomic variation. A significant correlation between the width of the knee-joint line and the depth of the nerve division could be demonstrated. We conclude that handheld ultrasound is able to depict the sciatic nerves division. To block the nerve by one injection a more proximal access or visualization by mobile ultrasound is recommended. In addition the surrounding anatomic structures can be depicted as well.

Prediction of depth of sedation and anaesthesia by the Narcotrend EEG monitor.

BACKGROUND: The Narcotrend (Monitor Technik, Bad Bramstedt, Germany) assesses sedation by automatic classification of EEG signals, using a scale first used for visual evaluation of the EEG. Limited information is available on its value, and only a few studies of the method exist. We set out to study the performance of the Narcotrend during propofol sedation. METHODS: In 23 ASA I-II patients, aged 18-65 yr, about to have general anaesthesia, we induced anaesthesia in steps using a target-controlled infusion of propofol. After equilibration for 8 min at each predicted propofol concentration (0.5, 1.0, 2.0, 3.0 and 4.0 microg x ml(-1)), sedation was assessed clinically with the modified Observer's Assessment of Alertness/Sedation Scale and the Narcotrend stage was noted. The prediction performance of the Narcotrend was assessed with the prediction probability P(K). A P(K) value of 1.0 means an exact prediction on every occasion, while a P(K) of 0.5 is no better than a 50:50 chance of being correct. RESULTS: In 12 women and 11 men (age 42 (sd 11) yr), a total of 138 measurements were made; 129 were analysed and nine were of poor signal quality. The prediction probability for the corresponding level of sedation was P(K)=0.92 (se 0.01); for the different target concentrations of propofol it was P(K) = 0.91 (se 0.01). CONCLUSIONS: The Narcotrend can monitor sedation with propofol. Other sedatives, anaesthetics and opioids should be used to test this monitor.

[Pain management in shoulder surgery]. / Perioperative Schmerzbehandlung in der Schulterchirurgie.

Surgical procedures in the region of the shoulder joint are among the most painful interventions in orthopedic practice. For this reason, in addition to intravenous pain therapy with opioids, blockade of the brachial plexus has become established as an effective method to provide analgesia.High-resolution ultrasound offers the possibility of performing nerve blockades under visual monitoring. Studies on interscalene blockade performed under sonographic control provide evidence for both the high efficacy and safety of the procedure. Clinically manifest signs of nerve damage have not appeared with use of this method. Smaller operations can usually be adequately managed with perioperative single-shot blockade. More extensive operations for which severe pain lasting for several days can be expected and surgical interventions involving preexistent shoulder stiffness necessitate catheterization for uninterrupted pain therapy. Successful rehabilitation after shoulder surgery requires diligent perioperative pain blockade, which can primarily be provided by interscalene plexus blockade.

Effects of intra-abdominal CO2-insufflation on normal and impaired myocardial function: an experimental study.

BACKGROUND: Intra-abdominal pressure (IAP) elevation during CO2-pneumoperitoneum increases cardiac afterload and may enhance dysfunction of the already compromised heart. This study focused on the effects of acute IAP increases on left and right ventricular loadings and contractility in the heart with impaired global function. METHODS: Impairment of myocardial function (IMF) was pharmacologically induced in 16 pigs by administration of halothane and propranolol, while baseline arterial pressure was maintained by intravenous phenylephrine. Intra-abdominal pressure was gradually increased by 10 mmHg up to 30 mmHg in the supine position (IMF group 1, n = 8) or in a head-down tilted position (IMF group 2, n = 8). In two control groups with normal myocardial function, IAP was also increased in the supine position or the head-down tilted position. Cardiac function in all groups was assessed by epicardial echocardiography, intraventricular pressure measurements and pulmonary artery catheterization. RESULTS: The increase in IAP was accompanied by a transient rise in LV end-systolic wall stress and reduced cardiac output significantly by 16-24% in all groups. In the IMF groups, LV end-diastolic transmural pressure increased by 34-60% to peak values of 24 mmHg, while cross-sectional LV end-diastolic areas remained unchanged. Increases in right ventricular end-diastolic volume and decreases in right ventricular ejection fraction as well as in cardiac output were most pronounced at IAP 20 mmHg and significantly stronger in both IMF groups than in the control groups (P < 0.001). CONCLUSION: Following the acute elevation of IAP, the right ventricular volume load shifted more extensively in the IMF groups than in the animals with normal myocardial function. Myocardial function in the impaired heart may worsen during IAP elevation due to right ventricular load alterations rather than a LV afterload increase.

[Extrahepatic portal vein thrombosis following laparoscopic cholecystectomy]. / Extrahepatische Pfortaderthrombose nach laparoskopischer Cholezystektomie.

Postoperative portal vein thrombosis is a rare complication, which occurs most often after hepatic surgery, but has not yet been described in combination with laparoscopic cholecystectomy. We present a case where thrombotic occlusion of the portal vein was diagnosed on the 6th day following laparoscopic cholecystectomy. Treatment with high-dose anticoagulant and antibiotic therapy was successful and without further complications.