Cycloaddition of Phenyltriazolinedione with Carbazole-Alkynes and Yne-Carbamates to Access Diazacyclobutenes.

Previously, we described the synthesis of stable, bicyclic examples of the rather rare diazacyclobutene (DCB) motif by means of a cycloaddition between triazolinediones and electron-rich thiolated alkynes. Here, we report the investigation of the cycloaddition of triazolinediones with related electron-rich yne-carbamates and carbazole-alkynes. Bicyclic DCBs arising from yne-carbamates were isolated in 8-65% yield, while those arising from carbazole-alkynes were isolated in 28-59% yield. Mechanistic studies and characterization of isolable byproducts shed light on the underlying issues leading to poor to moderate yields.

Telescoped Oxidation and Cycloaddition of Urazoles to Access Diazacyclobutenes.

Our previous method to access the diazacyclobutene scaffold did not allow for modification of the substituent originating from the 1,2,4-triazoline-3,5-dione component. We have circumvented this challenge and expanded access to additional structural diversity of the scaffold. A telescoped urazole oxidation and Lewis acid-catalyzed cyclization provided R3-substituted diazacyclobutenes. Calcium hypochlorite-mediated oxidation of urazoles followed by MgCl2-catalyzed cyclization of the resulting triazolinediones with thioalkynes promoted the formation of diazacyclobutenes bearing substitution at the R3 position originating from the triazolinedione component.

Impact of a CPR feedback device on healthcare provider workload during simulated cardiac arrest.

OBJECTIVE: We aimed to describe the differences in workload between team leaders and CPR providers during a simulated pediatric cardiac arrest, to evaluate the impact of a CPR feedback device on provider workload, and to describe the association between provider workload and the quality of CPR. METHODS: We conducted secondary analysis of data from a randomized trial comparing CPR quality in teams with and without use of a real-time visual CPR feedback device [1]. Healthcare providers (team leaders and CPR providers) completed the NASA Task Load Index survey after participating in a simulated cardiac arrest scenario. The effect of provider roles and real-time feedback on workload were compared with independent t-tests. RESULTS: Team leaders reported higher levels of mental demand, temporal demand, performance-related workload and frustration, while CPR providers reported comparatively higher physical workload. CPR providers reported significantly higher average workload (control 58.5 vs. feedback 62.3; p = 0.035) with real-time feedback provided compared to the group without feedback. Providers with high workloads (average score >60) had an increased percentage of time with guideline-compliant CPR depth versus those with low workloads (average score <60) (p = 0.034). CONCLUSIONS: Healthcare providers reported high workloads during a simulated pediatric cardiac arrest. Physical and mental workloads differed based on provider role. CPR providers using a CPR feedback device reported increased average workloads. The quality of CPR improved with higher reported physical workloads.

Causes for Pauses During Simulated Pediatric Cardiac Arrest.

OBJECTIVES: Pauses in cardiopulmonary resuscitation negatively impact clinical outcomes; however, little is known about the contributing factors. The objective of this study is to determine the frequency, duration, and causes for pauses during cardiac arrest. DESIGN: This is a secondary analysis of video data collected from a prospective multicenter trial. Twenty-six simulated pediatric cardiac arrest scenarios each lasting 12 minutes in duration were analyzed by two independent reviewers to document events surrounding each pause in chest compressions. SETTING: Ten children's hospitals across Canada, the United, and the United Kingdom. SUBJECTS: Resuscitation teams composed of three healthcare providers trained in cardiopulmonary resuscitation. INTERVENTIONS: A simulated pediatric cardiac arrest case in a 5 year old. MEASUREMENTS AND MAIN RESULTS: The frequency, duration, and associated factors for each pause were recorded. Communication was rated using a four-point scale reflecting the team's shared mental model. Two hundred fifty-six pauses were reviewed with a median of 10 pauses per scenario (interquartile range, 7-12). Median pause duration was 5 seconds (interquartile range, 2-9 s), with 91% chest compression fraction per scenario (interquartile range, 88-94%). Only one task occurred during most pauses (66%). The most common tasks were a change of chest compressors (25%), performing pulse check (24%), and performing rhythm check (15%). Forty-nine (19%) of the pauses lasted greater than 10 seconds and were associated with shock delivery (p < 0.001), performing rhythm check (p < 0.001), and performing pulse check (p < 0.001). When a shared mental model was rated high, pauses were significantly shorter (mean difference, 4.2 s; 95% CI, 1.6-6.8 s; p = 0.002). CONCLUSIONS: Pauses in cardiopulmonary resuscitation occurred frequently during simulated pediatric cardiac arrest, with variable duration and underlying causes. A large percentage of pauses were greater than 10 seconds and occurred more frequently than the recommended 2-minute interval. Future efforts should focus on improving team coordination to minimize pause frequency and duration.