Variation of Cognitive Function During a Short Stay at Hypobaric Hypoxia Chamber (Altitude: 3842 M).

Objective: To observe the effects of a fast-acute ascent to high altitude on brain cognitive function and transcranial doppler parameters in order to understand the physiological countermeasures of hypoxia.

Methods: 17 high-altitude-naïve male subjects (mean age was 26.3 ± 8.

Late cataclysmic hemorrhage from the innominate artery after tracheostomy.

We report on 12 patients sustaining late cataclysmic hemorrhage as a complication of tracheostomy or endotracheal intubation, resulting from erosion of the innominate artery. Four long-term survivors are reported. A number of surgical techniques was used and up-to-date management is briefly described.

Prevention and treatment of complications and sequelae of tracheal resection anastomosis.

Deaths following tracheal resection anastomosis for tumoral or iatrogenic disease have become fairly rare (four deaths in 122 cases in our experience). Complications can usually be prevented or treated successfully. The most common of these were: infectious lesions of the operated area (6 cases), infection of the tracheal anastomosis with subsequent disruption (1 case), erosion of the innominate artery (no case), granulomatous lesions and recurrence of stenosis (3 cases).

Measurement of H- density in plasma by photodetachment.

Techniques have been developed for measurement of the density of H- in a plasma by photodetachment. Photodetachment is detected by the increase in electron density with no change in positive ion density after a light pulse from a ruby laser. The authenticity of photodetachment signals can be assured by their comparison with known cross sections for photodetachment of H-.