Background: Residual neuromuscular blockade increases the risk to develop postoperative complications. The authors hypothesized that minimal neuromuscular blockade (train-of-four [TOF] ratio 0.5-1) increases upper airway collapsibility and impairs upper airway dilator muscle compensatory responses to negative pharyngeal pressure challenges. Methods: Epiglottic and nasal mask pressures, genioglossus electromyogram, respiratory timing, and changes in lung volume were measured in awake healthy volunteers (n = 15) before, during (TOF = 0.5 and 0.8 [steady state]), and after recovery of TOF to unity from rocuronium-induced partial neuromuscular blockade. Passive upper airway closing pressure (negative pressure drops, random order, range +2 to -30 cm H2O) and pressure threshold for flow limitation were determined. Results: Upper airway closing pressure increased (was less negative) significantly from baseline by 54 +/- 4.4% (means +/- SEM), 37 +/- 4.2%, and 16 +/- 4.1% at TOF ratios of 0.5, 0.8, and 1.0, respectively (P < 0.01 vs. baseline for any level). Phasic genioglossus activity almost quadrupled in response to negative (-20 cm H2O) pharyngeal pressure at baseline, and this increase was significantly impaired by 57 +/- 44% and 32 +/- 6% at TOF ratios of 0.5 and 0.8, respectively (P < 0.01 vs. baseline). End-expiratory lung volume, respiratory rate, and tidal volume did not change. Conclusion: Minimal neuromuscular blockade markedly increases upper airway closing pressure, partly by impairing the genioglossus muscle compensatory response. Increased airway collapsibility despite unaffected values for resting ventilation may predispose patients to postoperative respiratory complications, particularly during airway challenges.

Teaching endotracheal intubation to medical students is a task provided by many academic anesthesia departments. We tested the hypothesis that teaching with a novel videolaryngoscope improves students' intubation skills. We prospectively assessed in medical students (2nd clinical year) intubation skills acquired by intubation attempts in adult anesthetized patients during a 60-hour clinical course using, in a randomized fashion, either a conventional Macintosh blade laryngoscope or a videolaryngoscope (C-MAC®). The latter permits direct laryngoscopy with a Macintosh blade and provides a color image on a video screen. Skills were measured before and after the course in a standardized fashion (METI Emergency Care Simulator) using a conventional laryngoscope. All 1-semester medical students (n = 93) were enrolled. The students' performance did not significantly differ between groups before the course. After the course, students trained with the videolaryngoscope had an intubation success rate on a manikin 19% higher (95% CI 1.1%-35.3%; P < 0.001) and intubated 11 seconds faster (95% CI 4-18) when compared with those trained using a conventional laryngoscope. The incidence of "difficult (manikin) laryngoscopy" was less frequent in the group trained with the videolaryngoscope (8% vs 34%; P = 0.005). Education using a video system mounted into a traditional Macintosh blade improves intubation skills in medical students.

Teaching emergency management should educate medical students not only for facts and treatment algorithms but also for time effective physical examination, technical skills, and team interaction. We tested the hypothesis, that using standardized emergency patients would be more effective in transmitting knowledge and skills compared with a more traditional teaching approach. Medical students (n = 242) in their fourth (second clinical) year were randomized to receive either training on standardized patients simulating 3 emergency settings (“acute chest pain,” “stroke,” and “acute dyspnea/asthma”) or traditional small group seminars. Before and after the respective training pathways, the students’ knowledge base (multiple-choice examination) and practical performance (objective structured clinical examination using 3 different emergency scenarios) were assessed. Teaching using standardized patients resulted in a significant albeit small improvement in objective structured clinical examination scores (61.2 ± 3 for the standardized patient trained group vs 60.3 ± 3.5 for the traditional seminar group; P = 0.017, maximum achievable score: 66), but no difference in the written examination scores (27.4 ± 2.4 vs 27.0 ± 4.4; P = 0.341; maximum achievable score: 30). Teaching management of emergencies using standardized patients can improve medical students’ performance in clinical tests, and a change from traditional seminars in favor of practice sessions with standardized patients does not compromise the learning of medical facts.

Infections with SARS-CoV-2 spread worldwide early in 2020. In previous winters, we had been treating patients with seasonal influenza. While creating a larger impact on the health care systems, comparisons regarding the intensive care unit (ICU) courses of both diseases are lacking. We compared patients with influenza and SARS-CoV-2 infections treated at a tertiary care facility offering treatment for acute respiratory distress syndrome (ARDS) and being a high-volume facility for extracorporeal membrane oxygenation (ECMO). Patients with COVID-19 during the first wave of the pandemic (n = 64) were compared to 64 patients with severe influenza from 2016 to 2020 at our ICU. All patients were treated using a standardized protocol. ECMO was used in cases of severe ARDS. Both groups had similar comorbidities. Time in ICU and mortality were not significantly different, yet mortality with ECMO was high amongst COVID-19 patients with approximately two-thirds not surviving. This is in contrast to a mortality of less than 40% in influenza patients with ECMO. Mortality was higher than estimated by SAPSII score on admission in both groups. Patients with COVID-19 were more likely to be male and non-smokers than those with influenza. The outcomes for patients with severe disease were similar. The study helps to understand similarities and differences between patients treated for severe influenza infections and COVID-19.

Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)-infection is associated with an extremely variable disease course. When interstitial pneumonia (IP) occurs, it can lead to acute respiratory distress syndrome and death. Serum Krebs von den Lungen-6 (KL-6) is an established marker of IP, but its role as a marker of SARS-CoV-2 pneumonia is debated. This bicentric study included 157 patients with SARS-CoV-2 pneumonia. The WHO Ordinal Scale for Clinical Improvement (0–10 points) was used to classify the clinical course. Serum samples were collected at admission, and on days 3 and 7 of hospitalization. KL-6 was measured by using automated chemiluminescence immunoassay. A total of 68 patients developed a severe SARS-CoV-2 pneumonia, 135 of them required oxygen, and 15 died during hospitalization. The patients requiring non-invasive ventilation, invasive ventilation, or extracorporeal membrane oxygenation had significantly higher serum KL-6 levels at admission. The serum KL-6 levels were tendentially higher in patients who died than in those who survived. Logistic regression identified serum KL-6 at a cut-off of 335 U/mL at admission as a significant predictor of severe SARS-CoV-2 pneumonia outcome. Serum KL-6 seems to be a candidate biomarker for the clinical routine to stratify patients with SARS-CoV-2 pneumonia for the risk of a severe disease outcome or death.

Hyperspectral imaging (HSI) is a non-invasive technology that provides information on biochemical tissue properties, including skin oxygenation and perfusion quality. Microcirculatory alterations are associated with organ dysfunction in septic COVID-19 patients. This prospective observational study investigated associations between skin HSI and organ dysfunction severity in critically ill COVID-19 patients. During the first seven days in the ICU, palmar HSI measurements were carried out with the TIVITA^® tissue system. We report data from 52 critically ill COVID-19 patients, of whom 40 required extracorporeal membrane oxygenation (ECMO). HSI parameters for superficial tissue oxygenation (StO₂) and oxygenation and perfusion quality (NPI) were persistently decreased. Hemoglobin tissue content (THI) increased, and tissue water content (TWI) was persistently elevated. Regression analysis showed strong indications for an association of NPI and weaker indications for associations of StO₂, THI, and TWI with sequential organ failure assessment (SOFA) scoring. StO₂ and NPI demonstrated negative associations with vasopressor support and lactate levels as well as positive associations with arterial oxygen saturation. These results suggest that skin HSI provides clinically relevant information, opening new perspectives for microcirculatory monitoring in critical care.