Transcutaneous monitoring as trigger for therapy of hypoxemia during sleep

Based on results on central chemosensitivity in cats, paired stimuli were applied for therapy to infants with central respiratory insufficiency of various degrees. An unspecific respiratory stimulus, e.g. light for 1 s, was followed by a jet of either O2 or 2% CO2 in O2 for 1.5 s. The unspecific and the chemical stimuli were interspaced by 0.5 s. The combined stimulation was repeated every 10 s. The program was triggered by using threshold values of transcutaneous pO2. In infants with intratrachial tubes or tracheostoma we used the end tidal pCO2 for triggering the stimulation. The method could prevent hypoxemia during sleep in non-ventilated subjects with sleep apnea syndromes or in infants with severe hypoxemia during sleep after being rescued from Sudden Infant Death Syndrome (SIDS). In patients with Ondine's Curse Syndrome (OCS) with its CO2 insensitivity, paired stimuli were used in order to condition the chemical function of the respiratory system. Polysomnograms from 310 clinically healthy infants including healthy siblings of SIDS victims revealed instability of arterial pO2 and low CO2 sensitivity during sleep within the second month and the fourth to ninth month of life, respectively. These data challenge the described method as a potential preventive or therapeutic measure to defeat SIDS and sleep apnea syndromes in conjunction with disturbed chemical regulation of respiration.