Different narcotic gases and concentrations for immobilization of ostrich embryos for in-ovo imaging.

In-ovo imaging using avian eggs has been described as a potential alternative to animal testing using rodents. However, imaging studies are hampered by embryonal motion producing artifacts. This study aims at systematically comparing isoflurane, desflurane and sevoflurane in three different concentrations in ostrich embryos. Biomagnetic signals of ostrich embryos were recorded analyzing cardiac action and motion. Ten groups comprising eight ostrich embryos each were investigated: Control, isoflurane (2%, 4%, and 6%), desflurane (6%, 12%, and 18%) and sevoflurane (3%, 5%, and 8%). Each ostrich egg was exposed to the same narcotic gas and concentration on development day (DD) 31 and 34. Narcotic gas exposure was upheld for 90 min and embryos were monitored for additional 75 min. Toxicity was evaluated by verifying embryo viability 24 h after the experiments. Initial heart rate of mean 148 beats/min (DD 31) and 136 beats/min (DD 34) decreased over time by 44-48 beats/minute. No significant differences were observed between groups. All narcotic gases led to distinct movement reduction after mean 8 min. Embryos exposed to desflurane 6% showed residual movements. Isoflurane 6% and sevoflurane 8% produced motion-free time intervals of mean 70 min after discontinuation of narcotic gas exposure. Only one embryo death occurred after narcotic gas exposure with desflurane 6%. This study shows that isoflurane, desflurane and sevoflurane are suitable for ostrich embryo immobilization, which is a prerequisite for motion-artifact free imaging. Application of isoflurane 6% and sevoflurane 8% is a) safe as no embryonal deaths occurred after exposure and b) effective as immobilization was observed for approx. 70 min after the end of narcotic gas exposure. These results should be interpreted with caution regarding transferability to other avian species as differences in embryo size and incubation duration exist.

[What is new in 2014 for the specialist in hospital internal medicine? The point of view of university hospital chief residents]. / L'année 2014 mise en perspective par les internistes hospitaliers.

The year 2014 was rich in significant advances in all areas of internal medicine. Many of them have an impact on our daily practice and on the way we manage one problem or another. From the use of the ultrasound for the diagnosis of pneumonia to the choice of the site of venous access and the type of line, and the increasing complexity of choosing an oral anticoagulant agent, this selection offers to the readers a brief overview of the major advances. The chief residents in the Service of internal medicine of the Lausanne University hospital are pleased to share their readings.