Couplet periodic breathing response to high carbon dioxide and low oxygen.

A breathing pattern is described which is characterized by a grouping of two breaths followed by a prolonged apnea and which may involve a mechanism different from at least one type of Cheyne-Stokes breathing. The pattern can be eliminated by breathing 9 percent O(2) or 10 percent CO(2). However, the pattern frequently persists during breathing of high oxygen.