FIELD: medicine. SUBSTANCE: method involves observing periodic breathing component of cardiac rhythm in 2-8 cardiocycle range as diagnostic index. The periodic component is expressed as power spectrum density. Standard percentile nomogram is built for power spectrum density dependence on children age. The obtained values are compared to the standard nomogram. Power spectrum density value belonging to area below 10 centiles, air-conducting tract state is considered as laryngostenosis decompensation. The area of 10 to 90 centiles is judged as compensation state. One above 90 centiles is judged as laryngostenosis subcompensation state. EFFECT: enhanced reliability of the method.
