[Severe impairment of peritoneal cavity muscles in intensive care patients (comparative anatomic studies of respiration)].

The vital function respiration is kept up by the modifiable basal activity of the thin muscles of the abdominal cavity. The diaphragm is an important part of the respiratory muscular system. The muscular system of the 'splanchnocranium' exhibits a normal spontaneous activity, which is mostly open in the laryngeal region and mostly closed in the anorectal continence organ. In animals missing an abdomen, e.g. turtles, we find that the complete abdominal muscle system is connected to the lungs functioning as respiratory muscles. The most powerful lungs that exist are found in birds. Their lungs, which are situated in a stiff thorax are only ventilated through the air compartments, mostly by the abdominal muscles. By this, the role of abdominal muscles for respiratory function is shown. We studied intensive care patients requiring ventilatory support and found that the electromyogram of the external abdominal oblique muscle can be impaired or extinguished. In some cases the cause is a polyneuropathy, which can be reversible. In consequence, positioning measures, as prone positioning are capable of preventing progressive deterioration of ventilation/perfusion relationship.