Impatience and uncertainty: Experimental decisions predict adolescents? field behavior

We study risk attitudes, ambiguity attitudes, and time preferences of 661 children and adolescents, aged ten to eighteen years, in an incentivized experiment. We relate experimental choices to field behavior. Experimental measures of impatience are found to be significant redictors of health related field behavior and saving decisions. In particular, more impatient children and adolescents are more likely to spend money on alcohol and cigarettes, have a higher body mass index (BMI) and are less likely to save money. Experimental measures for risk and ambiguity attitudes are only weak predictors of field behavior.experiments with children and adolescents; risk; ambiguity; time preferences; health status; savings; external validity; field behavior.

Revisiting the relevance of economic theory to hotel revenue management education and practice in the era of Big Data

Abstract This paper explores the role of economics in hospitality education and industry practice, with a particular focus on revenue management, and puts forward an argument for a return to the inclusion of economic theory in UK hospitality education, not seen since the 1990s. Given the increasing amounts of pricing data available to both managers and customers and the consequent market complexities now seen, developing economic literacy is demonstrated to be a crucial skill required for future hospitality graduates, allowing them to make successful revenue decisions and sense-check with confidence the decisions made by automated revenue systems. Economic literacy is defined as a balanced understanding of economic theory that can be applied in real-life business scenarios, extending beyond simple consideration of supply and demand to a mixture of neoclassical and behavioural approaches to economics

Rationale and design of the PeriOperative ISchemic Evaluation-3 (POISE-3) : a randomized controlled trial evaluating tranexamic acid and a strategy to minimize hypotension in noncardiac surgery

Altres ajuts: Canadian Institutes of Health Research (CIHR, FDN-143302); General Research Fund (14104419), Research Grant Council, Hong Kong SAR, China; National Health and Medical Research Council, Funding Schemes (NHMRC Project Grant 1162362), Australia; McMaster University Department of Medicine Career Research Award and a Physicians' Services Incorporated (PSI) Foundation Mid-Career Clinical Research Award.Background: For patients undergoing noncardiac surgery, bleeding and hypotension are frequent and associated with increased mortality and cardiovascular complications. Tranexamic acid (TXA) is an antifibrinolytic agent with the potential to reduce surgical bleeding; however, there is uncertainty about its efficacy and safety in noncardiac surgery. Although usual perioperative care is commonly consistent with a hypertension-avoidance strategy (i.e., most patients continue their antihypertensive medications throughout the perioperative period and intraoperative mean arterial pressures of 60 mmHg are commonly accepted), a hypotension-avoidance strategy may improve perioperative outcomes. Methods: The PeriOperative Ischemic Evaluation (POISE)-3 Trial is a large international randomized controlled trial designed to determine if TXA is superior to placebo for the composite outcome of life-threatening, major, and critical organ bleeding, and non-inferior to placebo for the occurrence of major arterial and venous thrombotic events, at 30 days after randomization. Using a partial factorial design, POISE-3 will additionally determine the effect of a hypotension-avoidance strategy versus a hypertension-avoidance strategy on the risk of major cardiovascular events, at 30 days after randomization. The target sample size is 10,000 participants. Patients ≥45 years of age undergoing noncardiac surgery, with or at risk of cardiovascular and bleeding complications, are randomized to receive a TXA 1 g intravenous bolus or matching placebo at the start and at the end of surgery. Patients, health care providers, data collectors, outcome adjudicators, and investigators are blinded to the treatment allocation. Patients on ≥ 1 chronic antihypertensive medication are also randomized to either of the two blood pressure management strategies, which differ in the management of patient antihypertensive medications on the morning of surgery and on the first 2 days after surgery, and in the target mean arterial pressure during surgery. Outcome adjudicators are blinded to the blood pressure treatment allocation. Patients are followed up at 30 days and 1 year after randomization. Discussion: Bleeding and hypotension in noncardiac surgery are common and have a substantial impact on patient prognosis. The POISE-3 trial will evaluate two interventions to determine their impact on bleeding, cardiovascular complications, and mortality. Trial registration: ClinicalTrials.gov NCT03505723. Registered on 23 April 2018

Rationale and design of the PeriOperative ISchemic Evaluation-3 (POISE-3): a randomized controlled trial evaluating tranexamic acid and a strategy to minimize hypotension in noncardiac surgery

Background For patients undergoing noncardiac surgery, bleeding and hypotension are frequent and associated with increased mortality and cardiovascular complications. Tranexamic acid (TXA) is an antifibrinolytic agent with the potential to reduce surgical bleeding; however, there is uncertainty about its efficacy and safety in noncardiac surgery. Although usual perioperative care is commonly consistent with a hypertension-avoidance strategy (i.e., most patients continue their antihypertensive medications throughout the perioperative period and intraoperative mean arterial pressures of 60 mmHg are commonly accepted), a hypotension-avoidance strategy may improve perioperative outcomes. Methods The PeriOperative Ischemic Evaluation (POISE)-3 Trial is a large international randomized controlled trial designed to determine if TXA is superior to placebo for the composite outcome of life-threatening, major, and critical organ bleeding, and non-inferior to placebo for the occurrence of major arterial and venous thrombotic events, at 30 days after randomization. Using a partial factorial design, POISE-3 will additionally determine the effect of a hypotension-avoidance strategy versus a hypertension-avoidance strategy on the risk of major cardiovascular events, at 30 days after randomization. The target sample size is 10,000 participants. Patients ≥45 years of age undergoing noncardiac surgery, with or at risk of cardiovascular and bleeding complications, are randomized to receive a TXA 1 g intravenous bolus or matching placebo at the start and at the end of surgery. Patients, health care providers, data collectors, outcome adjudicators, and investigators are blinded to the treatment allocation. Patients on ≥ 1 chronic antihypertensive medication are also randomized to either of the two blood pressure management strategies, which differ in the management of patient antihypertensive medications on the morning of surgery and on the first 2 days after surgery, and in the target mean arterial pressure during surgery. Outcome adjudicators are blinded to the blood pressure treatment allocation. Patients are followed up at 30 days and 1 year after randomization. Discussion Bleeding and hypotension in noncardiac surgery are common and have a substantial impact on patient prognosis. The POISE-3 trial will evaluate two interventions to determine their impact on bleeding, cardiovascular complications, and mortality. Trial registration ClinicalTrials.gov NCT03505723. Registered on 23 April 2018

Comparison of five video laryngoscopes and conventional direct laryngoscopy : Investigations on simple and simulated difficult airways on the intubation trainer

INTRODUCTION Securing the airway with a tracheal tube is essential in emergency situations, in the intensive care setting as well as during anesthesia for surgery and other interventions. Current methods of airway assessment are poor screening tests for predicting difficult direct laryngoscopy due to a generally low positive predictive value; therefore, successful endotracheal intubation requires a high level of expertise, regular training and practice and sometimes additional tools. Currently, several video laryngoscopes (VL) with different designs are commercially available and have been investigated in a wide variety of settings. To our knowledge there is no prospective study evaluating and comparing performance among these three groups of VL; therefore, the aim of this study was to compare performance of five VL and conventional direct laryngoscopy in an intubation manikin model, both in a normal and simulated difficult intubation setting. METHODS In this study 10 residents, 12 senior staff physicians and 5 anesthesia nurses, all experienced in conventional direct laryngoscopy and inexperienced with VL underwent theoretical and hands-on training with all VL lasting 60 min. Afterwards participants performed intubation with all 5 VL and conventional direct laryngoscopy in a randomized sequence using an intubation manikin with normal intubation settings. Thereafter participants performed intubation in a simulated difficult intubation setting using the same intubation manikin with a neck collar to immobilize the cervical spine. In this study, the C-MAC(®) with Macintosh blade size 3, GlideScope(®) size 3, McGrath(®) series 5, King Vision(®) and Airtraq(®) size 2 were used. Time to intubation served as primary outcome and time to glottis visualization, number of intubation attempts, success rate and subjective evaluation of difficulty served as secondary outcomes. RESULTS In the normal intubation setting, time to intubation ranged from 16.0 s (conventional direct laryngoscopy) to 34.3 s (McGrath). GlideScope and conventional direct laryngoscopy were successful in 100 % followed by C-MAC (96.7 %), Airtraq (88.9 %), King Vision (77.8 %) and McGrath VL (44.4 %). In the simulated difficult intubation setting, time to intubation ranged between 20.3 s (Airtraq) and 26.7 s (McGrath). Success rate with C-MAC was 100 %, followed by GlideScope (96.7 %), Airtraq (85.2 %), conventional direct laryngoscopy (85.2 %), King Vision (81.5 %) and McGrath VL (70.4 %). CONCLUSION In the manikin with normal intubation setting, conventional direct laryngoscopy using a Macintosh blade was convincing and superior to any VL used in this study. During simulated difficult intubation, a blade with video transmission, such as C-MAC and the GlideScope were superior compared to conventional direct laryngoscopy and any other VL tested

Vergleich von fünf Videolaryngoskopen und direkter konventioneller Laryngoskopie: Untersuchung des einfachen und simulierten schwierigen Atemweg am Intubationstrainer

Zusammenfassung: Einleitung: Ziel dieser Studie war es, die Erfolgsrate von 5 verschiedenen Videolaryngoskopen (VL) unterschiedlichster Bauweise mit der direkten konventionellen Laryngoskopie (DKL) für das Management einer einfachen und simuliert-schwierigen Intubation am Intubationstrainer zu vergleichen. Methodik: Zehn Anästhesisten in Weiterbildung, 12 Fachärzte für Anästhesie und 5 Anästhesiepflegekräfte, allesamt erfahren mit DKL und unerfahren mit VL, unterzogen sich einem 60 min dauernden theoretischen und praktischen Training in der Handhabung der verschiedenen VL. Im Anschluss an das Training erfolgten in randomisierter Reihenfolge die Intubationen mit allen 5 VL und DKL am Intubationstrainer mit einfachem Atemweg. Im Anschluss wurden erneut in randomisierter Reihenfolge Intubationen mit allen 5 VL und DKL am Intubationstrainer mit simuliert-schwierigem Atemweg durchgeführt. Die schwierige Intubation wurde durch die Anlage eines "stiff neck" zur Immobilisation der Halswirbelsäule simuliert. In dieser Studie wurden das C-MAC®-VL mit Laryngoskopspatel nach Macintosh, Gr. 3, GlideScope®-VL, Gr. 3, McGrath®-VL Serie 5, King-Vision®-VL, Gr. 3, und Airtraq®-Vl, Gr. 2, verwendet. Primärer Endpunkt war die Intubationszeit. Als sekundäre Endpunkte dienten Zeit bis zur Glottisdarstellung, Anzahl der Intubationsversuche, Erfolgsrate und subjektive Einschätzung der Schwierigkeit jeder Technik. Resultate: Bei der einfachen Intubation betrug die Intubationszeit zwischen 16,0 s (DKL) und 34,3 s (McGrath-VL). GlideScope-VL und DKL hatten Erfolgsraten von 100 %, gefolgt von C-MAC- (96,7 %), Airtraq- (88,9 %), King-Vision- (77,8 %) und McGrath-VL (44,4 %). Bei der simuliert-schwierigen Intubation reichte die Intubationszeit von 20,3 s (Airtraq-VL) bis 26,7 s (McGrath-VL). Die Erfolgsrate mit dem C-MAC-VL betrug 100 %, gefolgt von GlideScope- (96,7%), Airtraq-VL (85,2 %), DKL (85,2 %), King-Vision- (81,5 %) und McGrath-VL (70,4 %). Schlussfolgerung: Beim Intubationstrainer mit einfachem Atemweg war die DKL allen VL überlegen. Bei der simuliert-schwierigen Intubation erzielten das C-MAC-VL mit Laryngoskopspatel nach Macintosh und das GlideScope-VL bessere Ergebnisse als die DKL oder die anderen VL

Monitoring der Tidalvolumina bei Verwendung des Ventrain® Notfallbeatmungsgeräts

BACKGROUND The Ventrain® emergency ventilation device allows active inspiration and expiration through transtracheal catheters or the lumen of an airway exchange catheter. This single-use handheld device is manually operated and driven by an external pressurized oxygen source. The Ventrain® may be used to ventilate patients with a complete or pending upper airway obstruction reducing the risk of barotrauma due to the possibility of active expiration. However tidal volumes (V T) applied and withdrawn with the Ventrain® can only be controlled by visual inspection of chest movements; V T monitoring is not provided. Excessive inspiratory volumes or air trapping due to insufficient expiration may remain clinically undetected until pulmonary trauma and/or cardio-respiratory deterioration occur. Active expiration itself carries the risk of overwhelming lung deflation with the formation of atelectasis. Thus, an inspiratory and expiratory tidal volume monitor is urgently required. The aim of this study was to evaluate efficacy and precision of the Florian respiratory function monitor (RFM) to monitor in- and expiratory V T administered by the Ventrain® emergency ventilation device through a small cannula to the ASL 5000 test lung (ASL). METHODS In an in-vitro setting the RFM was used with its neonatal flow sensor to monitor inspiratory and expiratory V T applied by the Ventrain® emergency ventilation device through a 2 mm internal diameter (ID) transtracheal catheter to the ASL. Driving flows of 6, 9, 12 and 15 l min(-1) were chosen to vary tidal volumes at a constant respiratory rate of 15 min(-1) and an I:E ratio of 1:1. Experiments were repeated five times with two flow sensors. An initial set-up calibration run was performed to calculate a bias correction factor for inspiratory and expiratory V T measured by the RFM. This bias correction factor was used to simulate a correction of the in the RFM programmed linearization table. In a second, identical setting the experiments were repeated five times with two flow sensors. V T measured by the adjusted RFM were compared with those obtained from the ASL 5000 in this second run and the percentage differences were calculated. Bland Altman analysis was used to investigate the agreement of inspiratory or expiratory VT measured by both methods (ASL and RFM). Calculation of the mean of differences between both methods is given as bias and the 95 % agreement interval as precision. RESULTS Tidal volumes measured by the ASL ranged from 140 to 675 ml. The percentage correction factor was 16.27 % (2.60 %) during inspiration for V T ranged from 0 to 700 ml and 11.51 % (2.56 %) during expiration for V T of 0 to 225 ml, 7.41 % (2.94 %) for VT 226 to 325 ml and 5.35 % (3.57 %) for TV e > 325 ml. Inspiratory and expiratory tidal volumes measured by the adjusted RFM demonstrated a percentage deviation (mean [SD]) of 2.59 % (1.86 %) during inspiration and 1.66 % (1.14 %) during expiration when compared with the ASL 5000. Bias (precision) of the Bland Altman plot for the adjusted RFM is 2.05 ml (23.20) during inspiration and 4.62 ml (10.40) for expiration. CONCLUSION The tested respiratory function monitor using hot-wire anemometer technology has the potential to monitor tidal volumes applied by the Ventrain®. With the software thus adapted, the RFM measures precise inspiratory and expiratory tidal volumes within common technical tolerance. This could help perform adequate patient ventilation with Ventrain® and reduce the potential risk of patient trauma