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Background Ultrasound education is propagated already during medical school due to its diagnostic importance. Courses are usually supervised by experienced faculty staff (FS) with patient bedside examinations or students among each other but often overbooked due to limited FS availability. To overcome this barrier, use of teaching videos may be advantageous. Likewise, peer teaching concepts solely with trained student tutors have shown to be feasible and effective. The aim was to evaluate 1) objective learning outcomes of a combined video-based, student-tutor (ViST) as compared to a FS-led course without media support, 2) acceptance and subjective learning success of the videos. Methods Two ultrasound teaching videos for basic and advanced abdominal ultrasound (AU) and transthoracic echocardiography (TTE) were produced and six students trained as tutors. Fourth-year medical students (N = 96) were randomized to either the ViST- or FS course (6 students per tutor). Learning objectives were defined equally for both courses. Acquired practical basic and advanced ultrasound skills were tested in an objective structured clinical examination (OSCE) using modified validated scoring sheets with a maximum total score of 40 points. Acceptance and subjective learning success of both videos were evaluated by questionnaires based on Kirkpatrick’s evaluation model with scale-rated closed and open questions. Results 79 of 96 medical students completed the OSCE and 77 could be finally analyzed. There was no significant difference in the mean total point score of 31.3 in the ViST (N = 42) and 32.7 in the FS course (N = 35, P = 0.31) or in any of the examined basic or advanced ultrasound skill subtasks. Of the 42 ViST participants, 29 completed the AU and 27 the TTE video questionnaire. Acceptance and subjective learning success of both videos was rated positively in 14–52% and 48–88% of the rated responses to each category, respectively. Attendance of either the student or faculty tutor was deemed necessary in addition to the videos. Conclusions A ViST versus FS teaching concept was able to effectively teach undergraduate students in AU and TTE, albeit acceptance of the teaching videos alone was limited. However, the ViST concept has the potential to increase course availability and FS resource allocation.

Early mobilization has become an important aspect of treatment in intensive care medicine, especially in patients with acute pulmonary dysfunction. As its effects on regional lung physiology have not been fully explored, we conceived a prospective observational study (Registration number: DRKS00023076) investigating regional lung function during a 15-min session of early mobilization physiotherapy with a 30-min follow-up period. The study was conducted on 20 spontaneously breathing adult patients with impaired pulmonary gas exchange receiving routine physical therapy during their intensive care unit stay. Electrical impedance tomography (EIT) was applied to continuously monitor ventilation distribution and changes in lung aeration during mobilization and physical therapy. Baseline data was recorded in the supine position, the subjects were then transferred into the seated and partly standing position for physical therapy. Afterward, patients were transferred back into the initial position and followed up with EIT for 30 min. EIT data were analyzed to assess changes in dorsal fraction of ventilation (%dorsal), end-expiratory lung impedance normalized to tidal variation (ΔEELI), center of ventilation (CoV) and global inhomogeneity index (GI index).Follow-up was completed in 19 patients. During exercise, patients exhibited a significant change in ventilation distribution in favor of dorsal lung regions, which did not persist during follow-up. An identical effect was shown by CoV. ΔEELI increased significantly during follow-up. In conclusion, mobilization led to more dorsal ventilation distribution, but this effect subsided after returning to initial position. End-expiratory lung impedance increased during follow-up indicating a slow increase in end-expiratory lung volume following physical therapy.

Zusammenfassung Hintergrund Nach Anlage eines zentralen Venenkatheters (ZVK) muss die Katheterlage kontrolliert und ein Pneumothorax ausgeschlossen werden. Fragestellung 1) Kann mittels Ultraschall über 2 aus der Notfallsonographie bekannte Schallfenster die korrekte i.v.-Lage und Richtung des Führungsdrahtes verifiziert und 2) die Lage der Katheterspitze vorhergesagt werden? Material und Methoden In diese Beobachtungsstudie wurden nach positivem Ethikvotum erwachsene Patienten mit Indikation für eine ZVK-Anlage der V. jugularis interna bzw. V. subclavia eingeschlossen. Nach Punktion und Vorschub des Führungsdrahtes wurde die V. cava entweder transhepatisch oder das rechte Herz von subkostal sonographiert und versucht, den Draht zu lokalisieren. Zur Positionierung wurde die einzuführende Katheterlänge in Bezug auf den kavoatrialen Übergang bestimmt, indem bei Rückzug und Verschwinden der Drahtspitze aus dem jeweiligen Schallfenster die eingeführte Drahtlänge gemessen wurde. Ergebnisse Von 100 Patienten konnten 94 ausgewertet werden. Der Führungsdraht war bei 91 Patienten verifizierbar. Bei 44 der 94 Patienten wurde die einzuführende Katheterlänge bestimmt. Bei 20 Patienten lag die Katheterspitze gemäß Thoraxröntgenaufnahme korrekt im unteren Drittel der V. cava superior, bei 14 Patienten zeigte sich eine relativ zu hohe bzw. tiefe Lage. Fünf Patienten wurden ausgeschlossen, da der ZVK für die Positionierung im Zielbereich zu kurz war. Diskussion Die hier vorgestellte Methode bestätigt zuverlässig die korrekte Richtung des Führungsdrahtes bereits vor dem Aufbougieren des Gefäßes. Sie erlaubt zusätzlich die Messung der einzuführenden Katheterlänge. Da auch der Ausschluss eines Pneumothorax sonographisch möglich ist, kann auf eine Thoraxröntgenaufnahme verzichtet werden.

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