End-tidal carbon dioxide monitoring may be associated with a higher possibility of return of spontaneous circulation during out-of-hospital cardiac arrest: a population-based study.

BACKGROUND: During cardiac arrest, end-tidal carbon dioxide (ETCO2) monitoring is recommended as a chest compression performance indicator. However, its frequency of use during out-of-hospital cardiac arrest (OHCA) and its benefits have never been evaluated in real clinical situations. OBJECTIVE: We investigated OHCA patients in Taiwan to evaluate the frequency of ETCO2 monitoring and its effects on sustained return of spontaneous circulation (ROSC). METHODS: We sampled the Taiwan National Health Insurance claims database, which contains 1 million beneficiaries. All adult beneficiaries older than 18 years who presented with OHCA and received chest compression between 1 January 2005 and 31 December 2012 were enrolled. We further identified patients with ETCO2 monitoring and matched each 1 with 20 patients who did not receive ETCO2 monitoring based on their propensity scores. A simple conditional logistic regression model was applied to compare the odds ratio (OR) for sustained ROSC in the matched cohorts. RESULTS: A total of 5041 OHCA patients were enrolled. The frequency of ETCO2 monitoring has increased since 2010 but still is low. After matching, 53 patients with ETCO2 monitoring and 1060 without ETCO2 monitoring were selected. The OR of sustained ROSC in the ETCO2 group was significantly increased (2.38, 95 % CI 1.28-4.42). CONCLUSION: Patients who received ETCO2 monitoring during OHCA had a higher possibility of sustained ROSC, but the overall use of ETCO2 monitoring is still low despite strong recommendations for its use.

Synthesis of coumarin/phenanthridine-fused heterocycles and their photochemical and thermochromic properties.

Four coumarin and phenanthridine-fused heterocycles were efficiently synthesized using base-mediated annulation of N-alkylquinolinium iodide and coumarin as a key step. One compound is found to be sensitive to light and changes color upon UV irradiation; the others are sensitive to heat and possess negative thermochromic properties. A novel light- and heat-sensitive molecular skeleton is introduced.