[Serious and sometimes fatal consequences of high-altitude pulmonary oedema]. / Ernstige en soms fatale gevolgen van hoogtelongoedeem.

Three women aged 25, 34 and 22 years respectively, experienced high-altitude pulmonary oedema during a climbing holiday. The first patient presented with complaints arising from a fast ascent to high altitude and was treated with acetazolamide and rapid descent. She recovered without any complications. The second patient developed symptoms during the night, which were not recognised as high-altitude pulmonary oedema. The next morning she died while being transported down on a stretcher without having received any medication or oxygen. The third case was not a specific presentation of high-altitude pulmonary oedema but autopsy revealed pulmonary oedema. This woman had already been higher up on the mountain before she developed complications. The cases illustrate the seriousness of this avoidable form of high altitude illness. The current Dutch national guidelines advise against the use of medication by lay people. A revision is warranted: travellers to high altitude should be encouraged to carry acetazolamide, nifedipine and corticosteroids on the trip. Travel guides ought to be trained to use these drugs. In addition climbing travellers should be encouraged to adopt appropriate preventive behaviour and to start descending as soon as signs of high-altitude pulmonary oedema develop.

In cat four times as many lamina I neurons project to the parabrachial nuclei and twice as many to the periaqueductal gray as to the thalamus.

The spinothalamic tract, and especially its fibers originating in lamina I, is the best known pathway for transmission of nociceptive information. On the other hand, different studies have suggested that more lamina I cells project to the parabrachial nuclei (PBN) and periaqueductal gray (PAG) than to the thalamus. The exact ratio of the number of lamina I projections to PBN, PAG and thalamus is not known, because comprehensive studies examining these three projections from all spinal segments, using the same tracers and counting methods, do not exist. In the present study, the differences in number and distribution of retrogradely labeled lamina I cells in each segment of the cat spinal cord (C1-Coc2) were determined after large wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) injections in either PBN, PAG or thalamus. We estimate that approximately 6000 lamina I cells project to PBN, 3000 to PAG and less than 1500 to the thalamus. Of the lamina I cells projecting to thalamus or PAG more than 80%, and of the lamina I-PBN cells approximately 60%, were located on the contralateral side. In all cases, most labeled lamina I cells were found in the upper two cervical segments and in the cervical and lumbar enlargements.