Pediatric Critical Care Fellow Perception of Learning through Virtual Reality Bronchoscopy.

Background: Virtual reality (VR) simulators have revolutionized training in bronchoscopy, offering unrestricted availability in a low-stakes learning environment and frequent assessments represented by automatic scoring. The VR assessments can be used to monitor and support learners' progression. How trainees perceive these assessments needs to be clarified. Objective: The objective of this study was to examine what assessments learners select to document and receive feedback on and what influences their decisions. Methods: We used a sequential explanatory mixed methods strategy. All participants were pediatric critical care medicine trainees requiring competency in bronchoscopy skills. During independent simulation practice, we collected the number of learning-focused practice attempts (scores not recorded), assessment-focused practice (scores recorded and reviewed by the instructor for feedback), and the amount of time each attempt lasted. After simulation training, we conducted interviews to explore learners' perceptions of assessment. Results: There was no significant difference in the number of attempts for each practice type. The average time per learning-focused attempt was almost three times longer than the assessment-focused attempt (mean [standard deviation] 16 ± 1 min vs. 6 ± 3 min, respectively; P < 0.05). Learners perceived documentation of their scores as high stakes and only recorded their better scores. Learners felt safer experimenting if their assessments were not recorded. Conclusion: During independent practice, learners took advantage of automatic assessments generated by the VR simulator to monitor their progression. However, the recording of scores from the simulation program to document learners' trajectory to a set goal was perceived as high stakes, discouraging learners from seeking supervisor feedback.

Designing and implementing a new icon-based difficult airway cart: a two-phase prospective qualitative improvement project.

PURPOSE: The difficult airway cart is essential for difficult airway management. Recognition of the importance of human factors in critical scenarios promoted the evolution of the difficult airway cart. Limitation to essential equipment, a structured layout, and proper labelling should be observed. We sought to redesign the difficult airway cart accordingly and analyze how perioperative professionals reacted to it. METHODS: We conducted a two-phase prospective qualitative improvement project involving a multidisciplinary team. In phase 1, we reconfigured our difficult airway cart, including developing icons for labelling the drawers and discussing the equipment content. In phase 2, we delivered a multidisciplinary educational program and pre- and postsession questionnaires were administered to the professionals involved and compared. RESULTS: Phase 1 of the project encompassed 21 participants. We presented the final layout and content of the difficult airway cart. In phase 2, 44 participants responded the presession questionnaires, and 30 participants answered the postsession questionnaires. The results showed that the new design and the implementation program increased the comfort level of professionals involved in a potential airway crisis (presession mean [standard deviation (SD)]: anesthesiologists, 8.0 [1.9]; anesthesia assistants/respiratory therapists [AAs/RTs], 9.3 [0.8]; operating room registered nurses [OR RNs], 6.3 [2.7]; P = 0.001; postsession: anesthesiologists, 8.5 [2.0]; AAs/RTs, 9.6 [0.5]; OR RN, 7.9 [2.0]; P = 0.10). Nevertheless, the improvement was only statistically significant among the OR RNs (presession mean [SD]: 6.3 [2.7]; postsession: 7.9 [2.0]; P = 0.01). Additionally, the program facilitated the recognition of the location of airway equipment in the airway cart (positive responses ranging from 97% to 100%). CONCLUSION: Our quality improvement project successfully designed and implemented a new visual-based difficult airway cart at our institution. We believe this report enables other institutions to reproduce our project.

RéSUMé: OBJECTIF: Le chariot d'intubation difficile est essentiel pour la prise en charge des voies aériennes difficiles. La reconnaissance de l'importance des facteurs humains dans les situations critiques a favorisé l'évolution du chariot d'intubation difficile. Il est crucial de se limiter à l'équipement essentiel tout en organisant les éléments de manière structurée et en les étiquetant adéquatement. Nous avons cherché à repenser le chariot d'intubation difficile en gardant ces éléments à l'esprit et à analyser la réaction des professionnel·les oeuvrant en périopératoire. MéTHODE: Nous avons réalisé un projet d'amélioration qualitative prospective en deux phases impliquant une équipe multidisciplinaire. Au cours de la phase 1, nous avons reconfiguré notre chariot d'intubation difficile, en développant notamment des icônes pour étiqueter les tiroirs et en discutant du contenu matériel. Au cours de la phase 2, nous avons mis en place un programme éducatif multidisciplinaire et des questionnaires ont été administrés aux professionnel·les concerné·es avant et après la session. RéSULTATS: La phase 1 du projet a réuni 21 participant·es. Nous avons présenté la disposition finale et le contenu du chariot d'intubation difficile. Au cours de la phase 2, 44 participant·es ont répondu aux questionnaires d'avant-session et 30 participant·es ont répondu aux questionnaires d'après-session. Les résultats ont montré que la nouvelle disposition avec icônes et le programme de mise en œuvre ont augmenté le niveau de confort des professionnel·les impliqué·es dans une situation critique potentielle impliquant les voies aériennes (moyenne avant la séance [écart type (ET)] : anesthésiologistes, 8,0 [1,9]; assistant·es en anesthésie/inhalothérapeutes, 9,3 [0,8]; personnel infirmier autorisé en salle d'opération (SOP), 6,3 [2,7]; P = 0,001; après la session : anesthésiologistes, 8,5 [2,0]; assistant·es en anesthésie/inhalothérapeutes, 9,6 [0,5]; personnel infirmier de SOP, 7,9 [2,0]; P = 0,10). Néanmoins, l'amélioration n'était statistiquement significative que chez le personnel infirmier autorisé de SOP (moyenne avant la session [ET] : 6,3 [2,7]; après la session : 7,9 [2,0]; P = 0,01). De plus, le programme a facilité la reconnaissance de l'emplacement de l'équipement pour les voies aériennes dans le chariot d'intubation (réponses positives allant de 97 % à 100 %). CONCLUSION: Dans le cadre de notre projet d'amélioration de la qualité, nous avons réussi à concevoir et mettre en œuvre un nouveau chariot d'intubation difficile avec icônes dans notre établissement. Nous pensons que ce compte rendu permettra à d'autres institutions de reproduire notre projet.

Carbon dioxide and cardiac output as major contributors to cerebral oxygenation during apnoeic oxygenation.

Apnoeic oxygenation has experienced a resurgence in interest in critical care and perioperative medicine. However, its effect on cerebral oxygenation and factors influencing it, have not yet been investigated in detail. By using near-infrared spectroscopy, we intended to provide further evidence for the safety of apnoeic oxygenation and to increase our understanding of the association between cerebral perfusion, haemodynamic, respiratory and demographic factors. In this secondary analysis of a prospective randomized controlled noninferiority trial, we recruited 125 patients, who underwent surgery under general anaesthesia with neuromuscular blockade. Arterial blood samples were taken every 2 min for a total of 15 min under apnoeic oxygenation with 100% oxygen. Near-infrared spectroscopy and cardiac output were continuously measured. Statistical analysis was performed using uni- and multivariable statistics. Ninety-one complete data sets were analysed. In six patients the SpO2 fell below 92% (predefined study termination criterion). The significant average increase of cerebral oxygenation was 0.5%/min and 2.1 mmHg/min for the arterial pressure of carbon dioxide (paCO2). The median cardiac output increased significantly from 5.0 l/min (IQR 4.5-6.0) to 6.5 l/min (IQR 5.7-7.5). The most significant effect on cerebral oxygenation was exhibited by the variable paCO2 and non-specific patient factors, followed by cardiac output and paO2. Apnoeic oxygenation proves to have a high safety profile while significantly increasing cerebral oxygenation, paCO2 and cardiac output. In reverse, NIRS might act as a reliable clinical surrogate of paCO2 and cardiac output during stable arterial oxygenation.

Teaching airway teachers: a post-course quantitative and qualitative survey.

BACKGROUND: Airway management is a crucial skill for many clinicians. Besides mastering the technical skills of establishing a patent airway, human factors including leadership and team collaboration are essential. Teaching these human factors is often challenging for instructors who lack dedicated training. Therefore, the European Airway Management Society (EAMS) developed the Teach-the-Airway-Teacher (TAT) course. METHODS: This online post-course survey of TAT-course participants 2013-2021 investigated the impact of the TAT-course and the status of airway management teaching in Europe. Twenty-eight questions e-mailed to participants (using SurveyMonkey) assessed the courses' strengths and possible improvements. It covered participants' and workplace details; after TAT-course considerations; and specifics of local airway teaching. Data were assessed using Excel and R. RESULTS: Fifty-six percent (119/213) of TAT-participants answered the survey. Most were anaesthetists (84%), working in university level hospitals (76%). Seventy-five percent changed their airway teaching in some way, but 20% changed it entirely. The major identified limitation to airway teaching in their departments was "lack of dedicated resources" (63%), and the most important educational topic was "Teaching non-technical skills" (70%). "Lecturing " was considered less important (37%). Most surveyed anaesthesia departments lack a standardized airway teaching rotation. Twenty-one percent of TAT-participants rated their departmental level of airway teaching overall as inadequate. CONCLUSIONS: This survey shows that the TAT-course purpose was successfully fulfilled, as most TAT-course participants changed their airway teaching approach and did obtain the EAMS-certificate. The feedback provided will guide future TAT-course improvements to advance and promote a comprehensive approach to teaching airway management.

Association Between Anesthesiologist Sex and Patients' Postoperative Outcomes: A Population-based Cohort Study.

OBJECTIVE: To examine the association of anesthesiologist sex on postoperative outcomes. BACKGROUND: Differences in patient postoperative outcomes exist, depending on whether the primary surgeon is male or female, with better outcomes seen among patients treated by female surgeons. Whether the intraoperative anesthesiologist's sex is associated with differential postoperative patient outcomes is unknown. METHODS: We performed a population-based, retrospective cohort study among adult patients undergoing one of 25 common elective or emergent surgical procedures from 2007 to 2019 in Ontario, Canada. We assessed the association between the sex of the intraoperative anesthesiologist and the primary end point of the adverse postoperative outcome, defined as death, readmission, or complication within 30 days after surgery, using generalized estimating equations. RESULTS: Among 1,165,711 patients treated by 3006 surgeons and 1477 anesthesiologists, 311,822 (26.7%) received care from a female anesthesiologist and 853,889 (73.3%) from a male anesthesiologist. Overall, 10.8% of patients experienced one or more adverse postoperative outcomes, of whom 1.1% died. Multivariable adjusted rates of the composite primary end point were higher among patients treated by male anesthesiologists (10.6%) compared with female anesthesiologists (10.4%; adjusted odds ratio 1.02, 95% CI: 1.00-1.05, P =0.048). CONCLUSIONS: We demonstrated a significant association between sex of the intraoperative anesthesiologist and patient short-term outcomes after surgery in a large cohort study. This study supports the growing literature of improved patient outcomes among female practitioners. The underlying mechanisms of why outcomes differ between male and female physicians remain elusive and require further in-depth study.

Use of a Novel Three-Dimensional Model to Teach Ultrasound-guided Subclavian Vein Cannulation.

Background: Central venous cannulation is an essential skill in perioperative and critical care medicine. Ultrasound guidance is the standard of care for femoral and internal jugular vein access, with the subclavian vein being perceived to be less amenable to ultrasound-guided (UG) insertion, resulting in a lack of procedural competency and low cannulation rate. There is a paucity of resources and a lack of experience among staff physicians to effectively instruct trainees. Simulation-based medical education has the potential to help maintain high-stakes, infrequently performed skills and counteract possible unrecognized skill decline. We aimed to create a novel, low-cost, high-fidelity three-dimensional (3D) model for UG subclavian vein (UG-SCV) access with an accompanying curriculum to improve this important skill. Methods: A curriculum was created consisting of preparatory material reviewing UG-SCV access, followed by an in-person didactic lecture focusing on ultrasound use and management of complications and a deliberate practice session scanning volunteers and practicing UG vascular puncture on a 3D model. A qualitative usability test design was used to assess the validity of the curriculum in trainees with advanced vascular access skills (anesthesiologists). Participants were second-year anesthesia residents, anesthesia fellows, and staff physicians. Focus groups conducted after each session explored the face validity of the model and curriculum. By applying a usability design, the curriculum was optimized and finalized. Results: Between September 2020 and February 2021, 28 participants tested the curriculum. The focus groups ensured that the curriculum achieved its objective, with iterative changes made after each session in a quality improvement framework Plan-Do-Study-Act approach. After the third cycle, minimal changes were suggested, and the curriculum and 3D model were finalized. An additional group of participants was used to ensure that no new input would help improve the curriculum further. Conclusions: A focused curriculum for enhancing skills in UG-SCV cannulation using a novel 3D model was successfully implemented and validated through a usability test design. This curriculum is better targeted for practitioners experienced in central venous access to master a subclavian approach and maintain their skill level.

Transforming traditional physiotherapy hands-on skills teaching into video-based learning.

BACKGROUND: Pandemic-induced restrictions forced curriculum transformation from on-site education to virtual learning options. This report describes this transition, the challenge of creating technology-enhanced learning for hands-on psychomotor skills teaching in physiotherapy, and students' evaluations of the new technology-enhanced learning approach in Complex Decongestive Physiotherapy. METHODS: On-site theoretical background lectures were replaced with e-learning sessions. Faculty hands-on skills demonstrations for the entire class were replaced with video-recorded demonstrations. Videos included verbal and written instructions and were complemented with checklists guiding the students, training in pairs, through their learning tasks. A cross-sectional observational survey for teaching quality evaluated this new technology-enhanced learning approach and assessed students' preference for traditional or video-based hands-on skills learning. RESULTS: Survey return rate was > 50% (46 participating students). Teaching quality was rated between 1.5 ± 0.5 and 1.8 ± 0.4 (Likert scale from - 2 to + 2). Most students (66.7%) preferred the new approach. They appreciated for example that videos were available all the time, enabling self-paced learning, providing an equally good view on skills demonstrations, and the convenience to be able to rewind, re-view, and use speed adjustment options. CONCLUSIONS: Students preferred the new video-based learning of skills for Complex Decongestive Physiotherapy. Because in-class live skills demonstrations were omitted, faculty had more time to provide individual feedback and answer questions. The shift from teacher- to student-centered learning enabled students to control their own learning pace. The innovative program was maintained after pandemic-induced restrictions were lifted. The success of this approach should be tested in other physiotherapy settings and different educational institutions.

Limitations of transcutaneous carbon dioxide monitoring in apneic oxygenation.

BACKGROUND: High-flow nasal oxygenation is increasingly used during sedation procedures and general anesthesia in apneic patients. Transcutaneous CO2 (ptcCO2)-monitoring is used to monitor hypercapnia. This study investigated ptcCO2-monitoring during apneic oxygenation. METHODS: We included 100 patients scheduled for elective surgery under general anesthesia in this secondary analysis of a randomized controlled trial. Before surgery, we collected ptcCO2 measured by TCM4 and TCM5 monitors and arterial blood gas (ABG) measurements every two minutes during 15 minutes of apnea. Bland-Altman plots analyzed agreement between measurement slopes; linear mixed models estimated the different measuring method effect, and outlined differences in slope and offset between transcutaneous and arterial CO2 partial pressures. RESULTS: Bland-Altman plots showed a bias in slope (95% confidence intervals) between ABG and TCM4-measurements of 0.05mmHg/min (-0.05 to 0.15), and limits of agreement were -0.88mmHg/min (-1.06 to -0.70) and 0.98mmHg/min (0.81 to 1.16). Bias between ABG and TCM5 was -0.14mmHg/min (-0.23 to -0.04), and limits of agreement were -0.98mmHg/min (-1.14 to -0.83) and 0.71mmHg/min (0.55 to 0.87). A linear mixed model (predicting the CO2-values) showed an offset between arterial and transcutaneous measurements of TCM4 (-15.2mmHg, 95%CI: -16.3 to -14.2) and TCM5 (-19.1mmHg, -20.1 to -18.0). Differences between the two transcutaneous measurements were statistically significant. CONCLUSIONS: Substantial differences were found between the two transcutaneous measurement systems, and between them and ABG. Transcutaneous CO2 monitoring cannot replace arterial CO2-monitoring during apneic oxygenation. In clinical settings with rapidly changing CO2-values, arterial blood gas measurements are needed to reliably assess the CO2-partial pressure in blood. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03478774).

Team leadership assessment after advanced life support courses comparing real teams vs. simulated teams.

Aim: Effective team leadership is essential during cardiopulmonary resuscitation (CPR) and is taught during international advanced life support (ALS) courses. This study compared the judgement of team leadership during summative assessments after those courses using different validated assessment tools while comparing two different summative assessment methods. Methods: After ALS courses, twenty videos of simulated team assessments and 20 videos of real team assessments were evaluated and compared. Simulated team assessment used an instructor miming a whole team, whereas real team assessment used course participants as a team that acted on the team leader's commands. Three examiners individually evaluated each video on four different validated team leadership assessment tools and on the original European Resuscitation Council's (ERC) scenario test assessment form which does not assess leadership. The primary outcome was the average performance summary score between all three examiners for each assessment method. Results: The average performance summary score for each of the four assessment tools was significantly higher for real team assessments compared to simulated team assessments (all p-values < 0.01). The summary score of the ERC's scenario test assessment form was comparable between both assessment methods (p = 0.569), meaning that participants of both assessments performed equally. Conclusion: Team leadership performance is rated significantly higher in real team summative assessments after ALS courses compared to simulated team assessments by four leadership assessment tools but not by the standard ERC's scenario test assessment form. These results suggest that summative assessments in ALS courses should integrate real team assessments, and a new assessment tool including an assessment of leadership skills needs to be developed.

Piloting a Basic Life Support instructor course: A short report.

Aim: The aim was to describe a new shortened pilot of the European Resuscitation Council's standard Basic Instructor Course. Methods: The four-hour pilot followed a blended learning strategy (pre-course preparation, on-site small-group sessions). Each participant taught a short Basic Life Support competency to the group (micro-teaching) and received the group's feedback. A feedback "drill" session followed. Primary quantitative outcome was the proportion of Basic Instructor Course participants subsequently teaching Basic Life Support. Post-course teachings were recorded and compared to standard eight-hour Basic Instructor Courses. Participants' open feedback question answers were qualitatively analyzed and presented descriptively. Results: This pilot Basic Instructor Course taught 31 healthcare providers in 4 courses in 2019-2021 (aged 31.5 ± 12.9 years; 61 % women; 29 % physicians; 71 % medical students; 21 % no teaching experience). Participants reported that they gained most from micro-teaching (64 %), and advice on their teaching (50 %). Some judged the course as being too long (29 %). Twenty-seven pilot course participants (87 %) (including three instructor candidates) started teaching, whereas only nine of 37 participants of the 3 courses (24 %, including three instructor candidates) from the standard eight-hour course did. Conclusion: Participants of the pilot shortened Basic Instructor Course in a healthcare setting were successfully trained to teach European Resuscitation Council's Basic Life Support provider courses in a short four-hour format. The pilot course seems to enable future instructors to teach Basic Life Support provider courses. Higher motivation to teach resulted in four times as many instructors who taught courses after the pilot course compared to the standard course.

Debriefing interaction patterns and learning outcomes in simulation: an observational mixed-methods network study.

BACKGROUND: Debriefing is effective and inexpensive to increase learning benefits of participants in simulation-based medical education. However, suitable communication patterns during debriefings remain to be defined. This study aimed to explore interaction patterns during debriefings and to link these to participants' satisfaction, perceived usefulness, and self-reported learning outcomes. METHODS: We assessed interaction patterns during debriefings of simulation sessions for residents, specialists, and nurses from the local anaesthesia department at the Bern University Hospital, Bern, Switzerland. Network analysis was applied to establish distinctive interaction pattern categories based on recorded interaction links. We used multilevel modelling to assess relationships between interaction patterns and self-reported learning outcomes. RESULTS: Out of 57 debriefings that involved 111 participants, discriminatory analyses revealed three distinctive interaction patterns: 'fan', 'triangle', and 'net'. Participants reported significantly higher self-reported learning effects in debriefings with a net pattern, compared to debriefings with a fan pattern. No effects were observed for participant satisfaction, learning effects after 1 month, and perceived usefulness of simulation sessions. CONCLUSIONS: A learner-centred interaction pattern (i.e. net) was significantly associated with improved short-term self-reported individual learning and team learning. This supports good-practice debriefing guidelines, which stated that participants should have a high activity in debriefings, guided by debriefers, who facilitate discussions to maximize the development for the learners.

Changes in lung volume estimated by electrical impedance tomography during apnea and high-flow nasal oxygenation: A single-center randomized controlled trial.

BACKGROUND: Previous studies concerning humidified, heated high-flow nasal oxygen delivered in spontaneously breathing patients postulated an increase in functional residual capacity as one of its physiological effects. It is unclear wheter this is also true for patients under general anesthesia. METHODOLOGY: The sincle-center noninferiority trial was registered at ClinicalTrials.gov (NCT NCT03478774). This secondary outcome analysis shows estimated differences in lung volume changes using electrical impedance tomography between different flow rates of 100% oxygen in apneic, anesthetized and paralyzed adults prior to intubation. One hundred and twenty five patients were randomized to five groups with different flow rates of 100% oxygen: i) minimal-flow: 0.25 l.min-1 via endotracheal tube; ii) low-flow: 2 l.min-1 + continuous jaw thrust; iii) medium-flow: 10 l.min-1 + continuous jaw thrust; iv) high-flow: 70l.min-1 + continuous jaw thrust; and v) control: 70 l.min-1 + continuous video-laryngoscopy. After standardized anesthesia induction with non-depolarizing neuromuscular blockade, the 15-minute apnea period and oxygen delivery was started according to the randomized flow rate. Continuous electrical impedance tomography measurements were performed during the 15-minute apnea period. Total change in lung impedance (an estimate of changes in lung volume) over the 15-minute apnea period and times to 25%, 50% and 75% of total impedance change were calculated. RESULTS: One hundred and twenty five patients completed the original study. Six patients did not complete the 15-minute apnea period. Due to maloperation, malfunction and artefacts additional 54 measurements had to be excluded, resulting in 65 patients included into this secondary outcome analysis. We found no differences between groups with respect to decrease in lung impedance or curve progression over the observation period. CONCLUSIONS: Different flow rates of humidified 100% oxygen during apnea result in comparable decreases in lung volumes. The demonstrated increase in functional residual capacity during spontaneous breathing with high-flow nasal oxygenation could not be replicated during apnea under general anesthesia with neuromuscular blockade.

Assessment of Human Factors After Advanced Life Support Courses Comparing Simulated Team and Real Team Assessment: A Randomized Controlled Cohort Trial.

Aim: Human factors are essential for high-quality resuscitation team collaboration and are, therefore, taught in international advanced life support courses, but their assessment differs widely. In Europe, the summative life support course assessment tests mainly adhere to guidelines but few human factors. This randomized controlled simulation trial investigated instructors' and course participants' perceptions of human factors assessment after two different summative assessments. Methods: All 5th/6th-year medical students who attended 19 advanced life support courses according to the 2015 European Resuscitation Council guidelines during one study year were invited to participate. Each course was randomized to either: (1) Simulated team assessment (one instructor simulates a team, and the assessed person leads this "team" through a cardiac-arrest scenario test); (2) Real team assessment (4 students form a team, one of them is assessed as the team leader; team members are not assessed and act only on team leader's commands). After the summative assessments, instructors, and students rated the tests' ability to assess human factors using a visual analog scale (VAS, 0 = no agreement, 10 = total agreement). Results: A total of 227 students participated in the 1-day Immediate Life Support courses, 196 students in the 2-day Advanced Life Support courses, additionally 54 instructors were included. Instructors judged all human factors significantly better in real team assessments; students rated leadership and situational awareness comparable between both assessments. Assessment pass rates were comparable between groups. Conclusion: Summative assessment in real teams was perceived significantly better to assess human factors. These results might influence current summative assessment practices in advanced life support courses.

Carbon Dioxide Changes during High-flow Nasal Oxygenation in Apneic Patients: A Single-center Randomized Controlled Noninferiority Trial.

BACKGROUND: Anesthesia studies using high-flow, humidified, heated oxygen delivered via nasal cannulas at flow rates of more than 50 l · min-1 postulated a ventilatory effect because carbon dioxide increased at lower levels as reported earlier. This study investigated the increase of arterial partial pressure of carbon dioxide between different flow rates of 100% oxygen in elective anesthetized and paralyzed surgical adults before intubation. METHODS: After preoxygenation and standardized anesthesia induction with nondepolarizing neuromuscular blockade, all patients received 100% oxygen (via high-flow nasal oxygenation system or circuit of the anesthesia machine), and continuous jaw thrust/laryngoscopy was applied throughout the 15-min period. In this single-center noninferiority trial, 25 patients each, were randomized to five groups: (1) minimal flow: 0.25 l · min-1, endotracheal tube; (2) low flow: 2 l · min-1, continuous jaw thrust; (3) medium flow: 10 l · min-1, continuous jaw thrust; (4) high flow: 70 l · min-1, continuous jaw thrust; and (5) control: 70 l · min-1, continuous laryngoscopy. Immediately after anesthesia induction, the 15-min apnea period started with oxygen delivered according to the randomized flow rate. Serial arterial blood gas analyses were drawn every 2 min. The study was terminated if either oxygen saturation measured by pulse oximetry was less than 92%, transcutaneous carbon dioxide was greater than 100 mmHg, pH was less than 7.1, potassium level was greater than 6 mmol · l-1, or apnea time was 15 min. The primary outcome was the linear rate of mean increase of arterial carbon dioxide during the 15-min apnea period computed from linear regressions. RESULTS: In total, 125 patients completed the study. Noninferiority with a predefined noninferiority margin of 0.3 mmHg · min-1 could be declared for all treatments with the following mean and 95% CI for the mean differences in the linear rate of arterial partial pressure of carbon dioxide with associated P values regarding noninferiority: high flow versus control, -0.0 mmHg · min-1 (-0.3, 0.3 mmHg · min-1, P = 0.030); medium flow versus control, -0.1 mmHg · min-1 (-0.4, 0.2 mmHg · min-1, P = 0.002); low flow versus control, -0.1 mmHg · min-1 (-0.4, 0.2 mmHg · min-1, P = 0.003); and minimal flow versus control, -0.1 mmHg · min-1 (-0.4, 0.2 mmHg · min-1, P = 0.004). CONCLUSIONS: Widely differing flow rates of humidified 100% oxygen during apnea resulted in comparable increases of arterial partial pressure of carbon dioxide, which does not support an additional ventilatory effect of high-flow nasal oxygenation.

The effective group size for teaching cardiopulmonary resuscitation skills - A randomized controlled simulation trial.

AIM OF THE STUDY: The ideal group size for effective teaching of cardiopulmonary resuscitation is currently under debate. The upper limit is reached when instructors are unable to correct participants' errors during skills practice. This simulation study aimed to define this limit during cardiopulmonary resuscitation teaching. METHODS: Medical students acting as simulated Basic Life Support course participants were instructed to make three different pre-defined Basic Life Support quality errors (e.g., chest compression too fast) in 7 min. Basic Life Support instructors were randomized to groups of 3-10 participants. Instructors were asked to observe the Basic Life Support skills and to correct performance errors. Primary outcome was the maximum group size at which the percentage of correctly identified participants' errors drops below 80%. RESULTS: Sixty-four instructors participated, eight for each group size. Their average age was 41 ± 9 years and 33% were female, with a median [25th percentile; 75th percentile] teaching experience of 6 [2;11] years. Instructors had taught 3 [1;5] cardiopulmonary resuscitation courses in the year before the study. A logistic binominal regression model showed that the predicted mean percentage of correctly identified participants' errors dropped below 80% for group sizes larger than six. CONCLUSION: This randomized controlled simulation trial reveals decreased ability of instructors to detect Basic Life Support performance errors with increased group size. The maximum group size enabling Basic Life Support instructors to correct more than 80% of errors is six. We therefore recommend a maximum instructor-to-participant ratio of 1:6 for cardiopulmonary resuscitation courses.

Prospective observational study evaluating the C-MAC Video Stylet for awake tracheal intubation: a single-center study.

BACKGROUND: The gold standard for management of known or predicted difficult airways is awake tracheal intubation. The newly developed C-MAC Video Stylet promises to combine the advantages of rigid stylets and flexible optical scopes. We therefore evaluated the feasibility of awake orotracheal intubations with this device. METHODS: In this prospective observational study, three anesthesiologists experienced in advanced airway management performed each 12 awake oral intubations with this device on adult patients with known or predicted intubation difficulties. The primary outcome was overall intubation success. Secondary outcomes were total attempts, successful time, first postoperative day sequelae, and subjective intubation difficulty rated on a visual analogue scale (1, very easy; 10, extremely difficult). RESULTS: Thirty-six patients (10 females), aged 64±13 years, with BMI 26±5 kg/m2, were enrolled in the study. ASA status II, III, IV were eight (22%), 23 (64%), and five (14%), respectively. Indications for awake oral intubation were: oropharyngeal tumor 20 (56%), cervical-spine fracture eight (22%), previously known difficult airway four (11%), spinal canal stenosis three (8%), and bilateral peritonsillar abscess one (3%). Overall, 97% were successfully intubated in 45 s (31-88). First-attempt success rate was 80% in 37 s (29-54); 92% of patients would choose the same procedure again. On the first postoperative day, 11 (31%) patients complained of sore throat; five (14%) had minor injuries. Ease of intubation was rated as median VAS 3 (IQR: 1-7). CONCLUSIONS: The new C-MAC Video Stylet has the potential to serve as a suitable device for visualized oral awake intubation in difficult airway situations.

Cricothyroidotomy competence and injuries using nonmedical equipment: A crossover noninferiority randomised controlled trial in a porcine cadaver model.

BACKGROUND: International guidelines recommend cricothyroidotomy as a life-saving procedure for 'cannot intubate, cannot ventilate' situations. Although commercially available sets facilitate surgical cricothyroidotomy, regular training seems to be the key to success. OBJECTIVES: The goal was to investigate if trained anaesthetists are able to transfer their skill in one surgical cricothyroidotomy technique to another. The primary hypothesis postulated that trained anaesthetists could perform an emergency cricothyroidotomy equally fast and successfully with a pocketknife compared with a surgical cricothyroidotomy set. DESIGN: Crossover noninferiority randomised controlled trial. SETTING: After written informed consent and ethics committee approval, this single-centre study was performed at the University Hospital of Bern, Bern, Switzerland. PARTICIPANTS: Altogether, 61 study participants already familiar with surgical cricothyroidotomy were included. INTERVENTION: The use of a commercially available cricothyroidotomy set was compared with a short-bladed pocketknife and ballpoint pen barrel. A pig-larynx cadaver model including trachea, with pig skin overlaid, was used. Participants underwent additional training sessions in both procedures. MAIN OUTCOME MEASURES: The primary outcome was the time necessary to position the tracheal tube or pen barrel in the trachea. Other outcome parameters were success rate, tracheal and laryngeal injuries and preferred device. RESULTS: Cricothyroidotomy with the pocketknife was performed significantly faster and equally successfully as compared with the cricothyroidotomy sets. Tracheal and laryngeal injuries were similar in both groups. Paratracheal or submucosal placement of the pen barrel occurred in 32%, compared with 29% for the tracheal tube. Sixty-six per cent of participants preferred the cricothyroidotomy set. CONCLUSION: Regularly trained anaesthetists are able to accomplish cricothyroidotomy irrespective of the equipment used. A pocketknife with a ballpoint pen barrel was just as effective as a commercially available surgical set.