We herein report the first case of low-dose oxygen therapy for pneumatosis cystoides intestinalis (PCI) using PaO2 as a therapeutic index to prevent acute exacerbation of interstitial pneumonia. An 86-year-old man was admitted to our hospital with abdominal distension. PCI was diagnosed by abdominal computed tomography. Low-dose oxygen therapy was started to avoid acute exacerbation of interstitial pneumonia. The oxygen dose was adjusted so that the PaO2 value was approximately 100 mmHg. After seven days of treatment, the colon gas had disappeared, and no acute exacerbation of interstitial pneumonia was observed. A PaO2 value around 100 mmHg is effective for PCI without inducing acute exacerbation of interstitial pneumonia.
Keywords: PaO2 level; interstitial pneumonia; low-dose oxygen therapy; pneumatosis cystoides intestinalis.