Mastering Sedation and Associated Respiratory Events through Simulation-Based Training: A Randomised Controlled Trial Involving Non-Anaesthesiology Residents.

Non-anaesthetists commonly administer procedural sedation worldwide, posing the risk of respiratory events that can lead to severe complications. This study aimed to evaluate whether simulation-based learning could lead to enhancements in the clinical proficiency of non-anaesthesiology residents in managing sedation and related respiratory complications. Following the evaluation of baseline clinical performance through a pre-test simulation, 34 residents were randomly allocated to either participate in an innovative simulation-based learning module (intervention group) or view a brief self-learning video (control group). After a one-month period, their clinical performance was assessed again in a post-test simulation involving respiratory arrest during procedural sedation. Two independent assessors rated each resident's performance using video recordings and a scoring tool with scores ranging from 0 to 19/19. The two assessments were averaged for each performance, and the pre- to post-test change was calculated for each resident. While baseline clinical performance was similar, mean (SD) increase in clinical performance was significantly greater in the intervention group than in the control group (+2.4 (1.6) points versus +0.8 (1.3) points, respectively; p = 0.002). Our simulation-based learning sedation module resulted in the enhanced management of sedation-related complications compared to baseline and minimal self-learning. Simulation-based medical education may offer an effective approach for equipping non-anaesthesiology residents with essential skills to mitigate risks associated with sedation. (ClinicalTrials.gov identifier: NCT02722226).

Simulation-based education to improve management of refractory anaphylaxis in an allergy clinic.

BACKGROUND: High-fidelity simulations based on real-life clinical scenarios have frequently been used to improve patient care, knowledge and teamwork in the acute care setting. Still, they are seldom included in the allergy-immunology curriculum or continuous medical education. Our main goal was to assess if critical care simulations in allergy improved performance in the clinical setting. METHODS: Advanced anaphylaxis scenarios were designed by a panel of emergency, intensive care unit, anesthesiology and allergy-immunology specialists and then adapted for the adult allergy clinic setting. This simulation activity included a first part in the high-fidelity simulation-training laboratory and a second at the adult allergy clinic involving actors and a high-fidelity mannequin. Participants filled out a questionnaire, and qualitative interviews were performed with staff after they had managed cases of refractory anaphylaxis. RESULTS: Four nurses, seven allergy-immunology fellows and six allergy/immunologists underwent the simulation. Questionnaires showed a perceived improvement in aspects of crisis and anaphylaxis management. The in-situ simulation revealed gaps in the process, which were subsequently resolved. Qualitative interviews with participants revealed a more rapid and orderly response and improved confidence in their abilities and that of their colleagues to manage anaphylaxis. CONCLUSION: High-fidelity simulations can improve the management of anaphylaxis in the allergy clinic and team confidence. This activity was instrumental in reducing staff reluctance to perform high-risk challenges in the ambulatory setting, thus lifting a critical barrier for implementing oral immunotherapy at our adult center.

High-Fidelity Simulation-Based Education: Description of an Original Crisis Resource Management and Sedation Learning for Dental Surgeons.

Dental surgery includes invasive procedures performed under sedation or monitored anesthesia care (MAC). It is associated with respiratory risks, resulting in death or neurological sequelae without prompt and appropriate management. Management of airway complications also implies mastering crisis resource management (CRM) principles, essentially non-technical skills to improve patient safety. In response to the need to enhance patient safety and to securely perform surgical procedures outside the operating room due to reduced surgical activity during the worldwide spread of the COVID-19 pandemic, we realized, in our simulation center, a course based on high fidelity simulation to teach procedural sedation and management of related complications. The simulation center accredited this educational program as a continuing professional development formation. The course includes technical skills practice, theoretical presentation, and mastering non-technical skills related to CRM principles. This brief report describes a relatively innovative teaching technique in dentistry, highlights its interest, and reports the subjective opinion of learners as to the pedagogical and professional impact of this training. A learner's satisfaction survey supports the utility of our sedation and CRM programs. A high degree of satisfaction and perceived value reflect robust learners' engagement. All medical specialties should encourage high-fidelity simulation continuing professional development courses that incorporate technical skills and crisis management principles.

The impact of a perceptual learning module on novices' ability to visually estimate left ventricular ejection fraction by transesophageal echocardiography: a randomized controlled study.

PURPOSE: Echocardiography is a difficult tool to master. Competency requires the supervised interpretation of hundreds of exams. Perceptual learning modules (PLMs) are novel learning tools that aim to speed up this learning process by enabling learners to go online and interpret numerous clinical images, followed systematically by expert feedback. We developed and tested a PLM aimed at improving novices' ability to quickly visually estimate left ventricular ejection fraction (LVEF) on transesophageal echocardiography images, a critical skill in acute care. We hypothesized that using the PLM would improve the accuracy and the speed of learners' estimations. METHODS: Learners without echocardiography experience were randomly assigned to a group that used the 96-case PLM (n = 26) or a control group (n = 26) that did not. Both groups took a pre-test and an immediate post-test that measured the accuracy of their visual estimations during a first session. At six months, participants also completed a delayed post-test. RESULTS: In the immediate post-test, the PLM group showed significantly better accuracy than the control group (median absolute estimation error 6.1 vs 9.0; difference 95% CI, 1.0 to 4.6; P < 0.001). Nevertheless, at six months, estimation errors were similar in both groups (median absolute estimation error 10.0 vs 10.0; difference 95% CI, -1.3 to 2.1; P = 0.27). CONCLUSIONS: Participation in a short online PLM significantly improved novices' short-term ability to accurately estimate LVEF visually, compared with controls. The effect was not sustained at six months. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT03245567); registered 7 August 2017.

RéSUMé: OBJECTIF: L'échocardiographie est un outil difficile à maîtriser. Afin d'acquérir cette compétence, l'interprétation supervisée de centaines d'examens est nécessaire. Les modules d'apprentissage perceptuel (MAP) sont des outils d'apprentissage innovants qui visent à accélérer ce processus d'apprentissage en permettant aux apprenants d'aller en ligne et d'interpréter de nombreuses images cliniques, lesquelles sont systématiquement suivies par des rétroactions d'experts. Nous avons mis au point et testé un MAP visant à améliorer la capacité des nouveaux apprenants à rapidement estimer visuellement la fraction d'éjection ventriculaire gauche (FEVG) sur des images d'échocardiographie transœsophagienne, une compétence critique dans les soins aigus. Nous avons émis l'hypothèse que l'utilisation du MAP améliorerait la précision et la rapidité des estimations des apprenants. MéTHODE: Les apprenants sans expérience de lecture d'échocardiographie ont été aléatoirement alloués à un groupe qui a utilisé le MAP de 96 cas (n = 26) ou à un groupe témoin (n = 26) qui ne l'a pas utilisé. Les deux groupes ont passé un prétest et un post-test immédiat qui ont mesuré l'exactitude de leurs estimations visuelles au cours d'une première séance. Six mois plus tard, les participants ont également passé un autre post-test retardé. RéSULTATS: Dans le post-test immédiat, le groupe MAP a démontré une précision significativement meilleure que le groupe témoin (erreur d'estimation absolue médiane, 6,1 vs 9,0; différence de l'IC 95 %, 1,0 à 4,6; P < 0,001). Néanmoins, à six mois, les erreurs d'estimation étaient similaires dans les deux groupes (erreur d'estimation absolue médiane, 10,0 vs 10,0; différence de l'IC 95 %, -1,3 à 2,1; P = 0,27). CONCLUSION: La participation à un bref MAP en ligne a considérablement amélioré la capacité à court terme des nouveaux apprenants à estimer visuellement et avec précision la FEVG, par rapport à un groupe témoin. L'effet n'était pas maintenu à six mois. ENREGISTREMENT DE L'éTUDE: www.clinicaltrials.gov (NCT03245567); enregistrée le 7 août 2017.

Comparing the Visual Perception According to the Performance Using the Eye-Tracking Technology in High-Fidelity Simulation Settings.

INTRODUCTION: We used eye-tracking technology to explore the visual perception of clinicians during a high-fidelity simulation scenario. We hypothesized that physicians who were able to successfully manage a critical situation would have a different visual focus compared to those who failed. METHODS: A convenience sample of 18 first-year emergency medicine residents were enrolled voluntarily to participate in a high-fidelity scenario involving a patient in shock with a 3rd degree atrioventricular block. Their performance was rated as pass or fail and depended on the proper use of the pacing unit. Participants were wearing pre-calibrated eye-tracking glasses throughout the 9-min scenario and infrared (IR) markers installed in the simulator were used to define various Areas of Interest (AOI). Total View Duration (TVD) and Time to First Fixation (TFF) by the participants were recorded for each AOI and the results were used to produce heat maps. RESULTS: Twelve residents succeeded while six failed the scenario. The TVD for the AOI containing the pacing unit was significantly shorter (median [quartile]) for those who succeeded compared to the ones who failed (42 [31-52] sec vs. 70 [61-90] sec, p = 0.0097). The TFF for the AOI containing the ECG and vital signs monitor was also shorter for the participants who succeeded than for those who failed (22 [6-28] sec vs. 30 [27-77] sec, p = 0.0182). DISCUSSION: There seemed to be a connection between the gaze pattern of residents in a high-fidelity bradycardia simulation and their performance. The participants who succeeded looked at the monitor earlier (diagnosis). They also spent less time fixating the pacing unit, using it promptly to address the bradycardia. This study suggests that eye-tracking technology could be used to explore how visual perception, a key information-gathering element, is tied to decision-making and clinical performance.

Using High-Fidelity Simulation to Teach Ethics Related Non-Technical Skills: Description of an Innovative Model.

This article describes a high-fidelity (Hi-Fi) simulation-based innovative educational strategy intended to introduce anesthesiology residents to key ethical considerations and how they apply to their practice. Three Hi-Fi simulation scenarios involving situations with various ethical issues are described with their debriefing objectives and the trainees' subjective feedback. Three high-fidelity simulation scenarios are described: (a) teaching critical incident disclosure, (b) disclosing and discussing patient awareness during general anesthesia, and (c) would physicians override a do-not-resuscitate (DNR) order if the cause of a cardiac arrest is iatrogenic? We used Hi-Fi simulation in an innovative way to teach these principles of ethics. Simulation, through carefully crafted debriefing, can contribute to the acquisition of essential non-technical ethical skills. How best to integrate simulation in an existent ethics curriculum and how it compares with more traditional teaching methods are questions that need to be addressed.

The impact of a high fidelity simulation-based debriefing course on the Debriefing Assessment for Simulation in Healthcare (DASH)© score of novice instructors.

INTRODUCTION: Experiential learning, followed by debriefing, is at the heart of Simulation-Based Medical Education (SBME) and has been proven effective to help master several medical skills. We investigated the impact of an educational intervention, based on high-fidelity SBME, on the debriefing competence of novice simulation instructors. METHODS: This is a prospective, randomized, quasi-experimental, pre- and post-test study. Sixty physicians without prior formal debriefing expertise attended a 5-day SBME seminar targeted on debriefing. Prior to the start of the seminar, 15 randomly chosen participants had to debrief a spaghetti and tape team exercise. Thereafter, the members of each team assessed their debriefer's performance using the Debriefing Assessment for Simulation in Healthcare (DASH)© score. The debriefing seminar that followed (intervention) consisted of 5 days of teaching that included theoretical and simulation training. Each scenario was followed by a Debriefing of the Debriefing (DOD) session conducted by the expert instructor. At the end of the course, 15 randomly chosen debriefers had to debrief a second tower building exercise and were re-evaluated with the DASH score by their respective team members. The Wilcoxon signed-rank test was used to compare pre- and post-test scores. Statistical tests were performed using GraphPad Prism 6.0c for Mac. RESULTS: A significant improvement in all items of the DASH score was noted following the seminar. The debriefers significantly improved their performance with regard to "maintaining an engaging learning environment" (Median [IQR]) (4[3-5] after the pre-test vs. 5.5[5-6] after the post-test, p<0.001); "structuring the debriefing in an organized way" (5[4-5] after the pre-test vs. 5[5-6] after the post-test, p=0.002); "provoking engaging discussion" (4[3-5.75] after the pre-test vs. 6[5-6] after the post-test, p<0.001); "identifying and exploring performance gaps" (5[4-6] after the pre-test vs. 6[5-6] after the post-test, p=0.014); and "helping trainees to achieve and sustain good future performance" (4[3-5] after the pre-test vs. 6[5-6] after the post-test, p<0.001). CONCLUSION: A simulation-based debriefing course, based mainly on DOD sessions, allowed novice simulation instructors to improve their overall debriefing skills including, more specifically, the ability to foster engagement in discussions and maintain an engaging learning environment.

Transcutaneous cardiac pacing competency among junior residents undergoing an ACLS course: impact of a modified high fidelity manikin.

BACKGROUND: Transcutaneous cardiac pacing (TCP) is recommended to treat unstable bradycardia. Simulation might improve familiarity with this low-frequency procedure. Current mannequins fail to reproduce key features of TCP, limiting their usefulness. The objective of this study was to measure the impact of a modified high-fidelity mannequin on the ability of junior residents to achieve six critical tasks for successful TCP. METHODS: First-year residents from various postgraduate programs taking an advanced cardiovascular life support (ACLS) course were enrolled two consecutive years (2015 and 2016). Both cohorts received the same standardized course content. An ALS simulator® mannequin was used to demonstrate and practice TCP during the bradycardia workshop of the first cohort (control cohort, 2015) and a modified high-fidelity mannequin that reproduces key features of TCP was used for the second cohort (intervention cohort, 2016). Participants were tested after training with a simulation scenario requiring TCP. Performances were graded based on six critical tasks. The primary outcome was the successful use of TCP, defined as having completed all tasks. RESULTS: Eighteen participants in the intervention cohort completed all tasks during the simulation scenario compared to none in the control cohort (36 vs 0%, p < 0.001). Participants in the intervention cohort were more likely to recognize when pacing was inefficient (86 vs 12%), obtain ventricular capture (48 vs 2%), and check for a pulse rate to confirm capture (48 vs 0%). CONCLUSIONS: TCP is a difficult skill to master for junior residents. Training using a modified high-fidelity mannequin significantly improved their ability to establish TCP during a simulation scenario.

Simulation-based assessment of anesthesiology residents' competence: development and implementation of the Canadian National Anesthesiology Simulation Curriculum (CanNASC).

The specialty of anesthesiology will soon adopt the Competence By Design (CBD) approach to residency education developed by the Royal College of Physicians and Surgeons of Canada (RCPSC). A foundational component of CBD is frequent and contextualized assessment of trainees. In 2013, the RCPSC Anesthesiology Specialty Committee assembled a group of simulation educators, representing each of the 17 Canadian anesthesiology residency programs, to form the Canadian National Anesthesiology Simulation Curriculum (CanNASC) Task Force. The goals were to develop, implement, and evaluate a set of consensus-driven standardized mannequin-based simulation scenarios that every trainee must complete satisfactorily prior to completion of anesthesiology residency and certification. Curriculum development followed Kern's principles and was accomplished via monthly teleconferences and annual face-to-face meetings. The development and implementation processes included the following key elements: 1) Curriculum needs assessment: 368 of 958 invitees (38.4%) responded to a national survey resulting in 64 suggested scenario topics. Use of a modified Delphi technique resulted in seven important and technically feasible scenarios. 2) Scenario development: All scenarios have learning objectives from the National Curriculum for Canadian Anesthesiology Residency. Standardized scenario templates were created, and the content was refined and piloted. 3) Assessment: A validated Global Rating Scale (GRS) is the primary assessment tool, informed by using scenario-specific checklists (created via a modified Delphi technique) and the Anesthesia Non-Technical Skills GRS. 4) Implementation: Standardized implementation guidelines, pre-brief/debrief documents, and rater training videos, guide, and commentary were generated. National implementation of the scenarios and program evaluation is currently underway. It is highly feasible to achieve specialty-based consensus on the elements of a national simulation-based curriculum. Our process could be adapted by any specialty interested in implementing a simulation-based curriculum incorporating competency-based assessment on a national scale.

Predictors of Difficult Intubation with the Bonfils Rigid Fiberscope.

BACKGROUND: Endotracheal intubation is commonly performed via direct laryngoscopy (DL). However, in certain patients, DL may be difficult or impossible. The Bonfils Rigid Fiberscope® (BRF) is an alternative intubation device, the design of which raises the question of whether factors that predict difficult DL also predict difficult BRF. We undertook this study to determine which demographic, morphologic, and morphometric factors predict difficult intubation with the BRF. METHODS: Four hundred adult patients scheduled for elective surgery were recruited. Patients were excluded if awake intubation, rapid sequence induction, or induction without neuromuscular blocking agents was planned. Data were recorded, including age, sex, weight, height, American Society of Anesthesiologist classification, history of snoring and sleep apnea, Mallampati class, upper lip bite test score, interincisor, thyromental and sternothyroid distances, manubriomental distances in flexion and extension, neck circumference, maximal neck flexion and extension, neck skinfold thickness at the cricoid cartilage, and Cormack and Lehane grade obtained via DL after paralysis was confirmed. Quality of glottic visualization (good or poor), as well as the number of intubation attempts and time to successful intubation with the BRF, was noted. Univariate analyses were performed to evaluate the association between patient characteristics and time required for intubation. Variables that exhibited a significant correlation were included in a multivariate analysis using a standard least squares model. A P < 0.05 was considered significant. RESULTS: Glottic visualization with the BRF was good in 396 of 400 (99%) cases. On the first attempt, 390 patients were successfully intubated with the BRF; 6 patients required >1 attempt; 4 patients could not be intubated by using the BRF alone. These 4 patients were intubated by using a combination of DL and BRF (2 patients), DL and a Frova bougie (1 patient), and DL and an endotracheal tube shaped with a semirigid stylet (1 patient). Mean time for successful intubation was 26 ± 13 seconds. Multivariate analysis showed that decreased mouth opening (P = 0.008), increased body mass index (P = 0.011), and higher Cormack and Lehane grade (P = 0.038) predicted longer intubation times, whereas shorter thyromental distance predicted slightly shorter intubation times (P < 0.0001). CONCLUSIONS: Mouth opening, body mass index, and high Cormack and Lehane grade predict longer intubation times, as with DL. Decreasing thyromental distance predicts slightly shorter intubation times with the BRF, possibly because of a design initially optimized for a pediatric population with receding chins. These findings, along with the high success rate of BRF in this study, and the possibility of further increasing success rates by combining BRF with DL, help define the role of BRF intubation in contemporary airway management.

[Hi-Fi simulation: Teaching crisis resource management to surgery residents]. / Simulation á haute fidélité: Moyen d'enseignement des principes de gestion de crises périopératoires aux residents de chirugie.

BACKGROUND: High-fidelity (HiFi) simulation has shown its effectiveness for teaching crisis resource management (CRM) principles, and our institutional experience in this area is mainly with anesthesiology residents. We recently added to our postgraduate curriculum a new CRM course designed to cater to the specific needs of surgical residents. AIM: This short communication describes the experience of the University of Montreal Simulation Centre (Centre d'Apprentissage des Attitudes et Habiletés Cliniques CAAHC) regarding HiFi simulationbased CRM and communication skills teaching for surgical residents. METHODS: Thirty residents agreed to participate in a simulation course with pre-established scenarios and educational CRM objectives on a voluntary basis. RESULTS: When surveyed immediately after the activity, all residents agreed that the educational objectives were well defined (80% "strongly agree" and 20% "agree"). The survey also showed that the course was well accepted by all participants (96% "strongly agree" and 4% "agree"). CONCLUSION: Further trials with randomized groups and more reliable assessment tools are needed to validate our results. Still, integrating HiFi simulation based CRM learning in the surgical residency curriculum seems like an interesting step.

High-fidelity simulation of transcutaneous cardiac pacing: characteristics and limitations of available high-fidelity simulators, and description of an alternative two-mannequin model.

INTRODUCTION: Transcutaneous cardiac pacing (TCP) is a potentially lifesaving technique that is part of the recommended treatment for symptomatic bradycardia. Transcutaneous cardiac pacing however is used uncommonly, and its successful application is not straightforward. Simulation could, therefore, play an important role in the teaching and assessment of TCP competence. However, even the highest-fidelity mannequins available on the market have important shortcomings, which limit the potential of simulation. METHODS: Six criteria defining clinical competency in TCP were established and used as a starting point in the creation of an improved TCP simulator. The goal was a model that could be used to assess experienced clinicians, an objective that justifies the additional effort required by the increased fidelity. RESULTS: The proposed 2-mannequin model (TMM) combines a highly modified Human Patient Simulator with a SimMan 3G, the latter being used solely to provide the electrocardiography (ECG) tracing. The TMM improves the potential of simulation to assess experienced clinicians (1) by reproducing key features of TCP, like using the same multifunctional pacing electrodes used clinically, allowing dual ECG monitoring, and responding with upper body twitching when stimulated, but equally importantly (2) by reproducing key pitfalls of the technique, like allowing pacing electrode misplacement and reproducing false signs of ventricular capture, commonly, but erroneously, used clinically to establish that effective pacing has been achieved (like body twitching, electrical artifact on the ECG, and electrical capture without ventricular capture). CONCLUSIONS: The proposed TMM uses a novel combination of 2 high-fidelity mannequins to improve TCP simulation until upgraded mannequins become commercially available.

Airway management in the patient with potential cervical spine instability: continuing professional development.

PURPOSE: Securing the airway of a patient with a potentially unstable cervical spine (C-spine) is a complex and challenging task. The objective of this continuing professional development module is to review the current knowledge essential for airway management in the face of potential C-spine instability and, at the same time, to underline areas of uncertainty and limitations in the literature. PRINCIPAL FINDINGS: In low-risk patients-defined by strict criteria derived from large multicentre studies-the C-spine can be considered stable or "cleared" without imaging. In all other patients, at least a thin-section computed tomographic examination of the spine from the occiput to T1 should be obtained, including sagittal and coronal multiplanar reconstructed images. Until the C-spine is cleared, it should be immobilized in the neutral position using a rigid cervical collar, sandbags, tape, and a backboard. During airway management, the anterior part of the cervical collar should be removed, and manual in-line stabilization should be applied. Some airway techniques, such as fibreoptic bronchoscopy and the Trachlight(®), have been shown to induce less C-spine movement than direct laryngoscopy; however, the impact of such airway management on outcome is uncertain. CONCLUSION: Adequate airway management in the patient with potential C-spine injury demands an understanding of C-spine anatomy, the criteria required to clear the C-spine, and the indications, techniques, and pitfalls of C-spine immobilization. When choosing an airway technique, minimization of C-spine motion should be considered, but the method of choice should also incorporate the broader clinical context.

Poor visualization during direct laryngoscopy and high upper lip bite test score are predictors of difficult intubation with the GlideScope videolaryngoscope.

BACKGROUND: The GlideScope videolaryngoscope allows equal or superior glottic visualization compared with direct laryngoscopy, but predictive features for difficult GlideScope intubation have not been identified. We undertook this prospective study to identify patient characteristics associated with difficult GlideScope intubation. METHODS: Demographic and morphometric factors were recorded preoperatively for 400 patients undergoing anesthesia with endotracheal intubation. After induction, direct laryngoscopy was performed in all patients to assess the Cormack and Lehane grade of glottic visualization followed by GlideScope intubation. The number of attempts and time needed for intubation were recorded. Univariate and multivariate analyses were performed to identify the characteristics associated with difficult GlideScope intubation. RESULTS: Intubation required 1, 2, and 3 attempts in 342, 48, and 9 participants, respectively, with one failure. Mean time for intubation was 21 +/- 14 s. After univariate analysis, the following characteristics were significantly correlated (P < 0.05) with longer time to intubate and/or multiple attempts: older age, male sex, history of snoring, high Mallampati class, small mouth opening, short sternothyroid and manubriomental distances, large neck circumference, high upper lip bite test score, and high Cormack and Lehane grade during direct laryngoscopy. However, after introducing these variables in nominal logistic and proportional hazard multiple regression models, only high Cormack and Lehane grade during direct laryngoscopy, high upper lip bite test score, and short sternothyroid distance were significantly associated with multiple attempts or lengthier intubations. CONCLUSION: Despite a high success rate, intubation with the GlideScope is likely to be more challenging in patients with high Cormack and Lehane grade during direct laryngoscopy, high upper lip bite test score, or short sternothyroid distance.

Cervical spine motion during tracheal intubation with manual in-line stabilization: direct laryngoscopy versus GlideScope videolaryngoscopy.

BACKGROUND: The optimal tracheal intubation technique for patients with potential cervical (C) spine injury remains controversial. Using continuous cinefluoroscopy, we conducted a prospective study comparing C-spine movement during intubation using direct laryngoscopy (DL) or GlideScope videolaryngoscopy (GVL), with uninterrupted manual in-line stabilization of the head by an assistant. METHODS: Twenty patients without C-spine pathology were studied. After induction of general anesthesia with neuromuscular blockade, both DL and GVL were performed on every patient in random order. Cinefluoroscopic images of C-spine movement during GVL and DL were acquired and divided into four stages: a baseline image before airway manipulation, glottic visualization, insertion of the endotracheal tube into the glottis, and tracheal intubation. Peak segmental motion from the occiput to C5 was measured offline for each patient and each stage, averages were calculated, and movements induced by each instrument were compared using a two-way ANOVA. Also studied were the proportion of patients with occiput-C1 rotation exceeding 10, 15, or 20 degrees, and the quality of glottic visualization. RESULTS: No significant difference was found between DL and GVL regarding average segmental spine movement at any level (P values between 0.22 and 0.70). During both techniques, motion was mainly an extension concentrated in the rostral C-spine and occurred predominantly during glottic visualization. The proportion of patients with occiput-C1 extension of more than 10, 15, or 20 degrees was not significantly different. Glottic visualization was significantly better with GVL compared with DL. CONCLUSION: During intubation under general anesthesia with neuromuscular blockade and manual in-line stabilization, the use of GVL produced better glottic visualization, but did not significantly decrease movement of the nonpathologic C-spine when compared with DL.

Importance of relative pulmonary hypertension in cardiac surgery: the mean systemic-to-pulmonary artery pressure ratio.

OBJECTIVE: To determine the importance of the mean arterial pressure-to-mean pulmonary artery pressure ratio (MAP/MPAP) in cardiac surgical patients. DESIGN: Retrospective and prospective studies (3 groups). SETTING: Tertiary care hospital. PARTICIPANTS: Cardiac surgical patients (1,557). INTERVENTION: Retrospective analysis (group 1), induction of general anesthesia (group 2), and transesophageal Doppler echocardiography (group 3). MEASUREMENTS AND MAIN RESULTS: In group 1 (n = 1,439), demographic, hemodynamic, and other perioperative variables were collected with follow-up until hospital discharge. The primary outcome was a composite index of hemodynamic complications that included death, resuscitated cardiac arrest, use of vasopressive drugs for >24 hours postoperatively, or the use of an intra-aortic balloon pump that was not present preoperatively. In group 2 (n = 34), the effect of general anesthesia on the MAP/MPAP ratio was studied, and Doppler echocardiography was used to evaluate diastolic profiles in group 3 (n = 74). In group 1, a total of 302 patients experienced hemodynamic complications (21%). The MAP/MPAP ratio was significantly lower in the patients who developed complications (3.3 +/- 1.3 v 4.0 +/- 1.4, p < 0.0001). Multiple stepwise logistic regression analysis showed the MAP/MPAP ratio to be an independent predictor of hemodynamic complications (p < 0.0001). In group 2, the induction of anesthesia decreased both MAP and MPAP, but the ratio remain unchanged (p = 0.242). In group 3, patients with moderate-to-severe diastolic dysfunction (DD) had a lower ratio (3.5 +/- 0.9 v 4.0 +/- 1.1 compared with those with normal-to-mild DD, p = 0.07). CONCLUSION: The MAP/MPAP ratio is a useful hemodynamic variable in cardiac surgery. It can be used to predict hemodynamic complications after cardiac surgery, is not influenced by the induction of anesthesia, and tends to correlate with the severity of left ventricular diastolic profiles.