<p> </p> <p class="MsoNormal" style="text-indent:30.0pt;mso-char-indent-count:3.0;
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mso-fareast-font-family:"Malgun Gothic"">Post-hyperventilation hypoxemia is caused by apnea and ventilation-perfusion mismatch of the lungs, which can lead to severe hypoxemia if the duration of apnea is prolonged. Hyperventilation syndrome after general anesthesia can cause prolonged apnea due to benzodiazepine, opioid, neuromuscular blocking agent and can make severe hypoxemia due to atelectasis. We experienced two patients with recurrent apnea and sudden hypoxemia after hyperventilation syndrome after general anesthesia. We were able to treat hyperventilation, which was not treated with the drug, with a rebreathing mask and to terminate the recurrence of apnea and hypoxemia.<o:p></o:p></span></p>