Kitajima Takamasa, Marumo Satoshi, Shima Hiroshi, Shirata Masahiro, Kawashima Satoru, Inoue Daiki, Katayama Yuko, Itotani Ryo, Sakuramoto Minoru, Fukui Motonari
Respiratory Disease Center, Kitano Hospital, Tazuke Kofukai Medical Research Institute, Osaka, Japan.
Int J Chron Obstruct Pulmon Dis. 2018 Mar 6;13:843-853. doi: 10.2147/COPD.S153200. eCollection 2018.
Episodic nocturnal hypercapnia (eNH) caused by rapid eye movement (REM) sleep-related hypoventilation is often noted in patients with advanced COPD. The purpose of this study was to clarify the clinical significance of eNH and the effectiveness of eNH-targeted noninvasive positive pressure ventilation (NPPV).
We enrolled patients with stable, severe, or very severe COPD with daytime arterial partial oxygen pressure PaO ≥55 mmHg and daytime arterial partial carbon dioxide pressure PaCO <55 mmHg, who underwent overnight transcutaneous carbon dioxide pressure (PtcCO) monitoring from April 2013 to April 2016. We retrospectively compared clinical characteristics, daytime blood gas analysis, frequency of exacerbation, serum albumin levels, and ratio of pulmonary artery to aorta diameter (PA:A ratio), between patients with COPD with and without eNH. For those with eNH, we applied NPPV and compared these clinical characteristics before and after NPPV.
Twenty-one patients were finally included in this study. Ten patients (47.6%) were evaluated to have eNH. These patients had lower albumin levels (=0.027), larger PA:A ratio (=0.019), and higher frequency of exacerbations during the last year (=0.036). NPPV for the patients with eNH improved daytime PaCO compared with that 12 months after NPPV (=0.011). The frequency of exacerbations 1 year before NPPV decreased 1 year after NPPV (=0.030). Serum albumin levels improved 1 year after NPPV (=0.001).
In patients with stable severe or very severe COPD, eNH may be a risk factor of exacerbations, hypoalbuminemia, and pulmonary hypertension. NPPV may be effective against hypoalbuminemia and acute exacerbations. However, further study is necessary to validate these findings.
快速眼动（REM）睡眠相关通气不足引起的发作性夜间高碳酸血症（eNH）在晚期慢性阻塞性肺疾病（COPD）患者中较为常见。本研究旨在阐明eNH的临床意义以及针对eNH的无创正压通气（NPPV）的有效性。
我们纳入了2013年4月至2016年4月期间接受过夜经皮二氧化碳分压（PtcCO）监测的稳定期重度或极重度COPD患者，其白天动脉血氧分压PaO₂≥55 mmHg且白天动脉血二氧化碳分压PaCO₂<55 mmHg。我们回顾性比较了有和没有eNH的COPD患者的临床特征、白天血气分析、急性加重频率、血清白蛋白水平以及肺动脉与主动脉直径比值（PA:A比值）。对于有eNH的患者，我们应用NPPV并比较了NPPV前后的这些临床特征。
本研究最终纳入21例患者。10例患者（47.6%）被评估为有eNH。这些患者白蛋白水平较低（P = 0.027），PA:A比值较大（P = 0.019），且过去一年急性加重频率较高（P = 0.036）。与NPPV 12个月后相比，eNH患者接受NPPV后白天PaCO₂有所改善（P = 0.011）。NPPV前1年的急性加重频率在NPPV后1年降低（P = 0.030）。NPPV 1年后血清白蛋白水平有所改善（P = 0.001）。
在稳定期重度或极重度COPD患者中，eNH可能是急性加重、低白蛋白血症和肺动脉高压的危险因素。NPPV可能对低白蛋白血症和急性加重有效。然而，需要进一步研究来验证这些发现。
