Sleep-induced apnea

✓ Data are reported on 10 patients who developed a syndrome of sleepinduced apnea preceded by lethargy and asthenia following bilateral percutaneous cervical cordotomy. Respiratory dysfunction occurred within 24 to 48 hours in most cases but appeared as early as 1 hour and as late as 6 days. One type of respiratory dysfunction was characterized by an attenuated CO 2 response with a normal vital capacity; in a second type an attenuated CO 2 response and a decreased vital capacity were both present. A variety of other autonomic dysfunctions were present in some of the patients; these included hypotension, hyponatremia, inappropriate antidiuretic hormone secretion, and difficulties in micturition. The syndrome lasted from 3 to 32 days in surviving patients. Five patients required endotracheal intubation. Three deaths were attributable to this syndrome; two occurred in patients who were not intubated and died in their sleep. The incidence of apnea during sleep, its reversal by arousal, and the absence of significant motor changes strongly suggest that the ascending reticular fibers in the ventrolateral segment of the spinal cord have been damaged.