太田 志代¹, 日高 庸博¹, 山本 亮¹, 笹原 淳¹, 石井 桂介¹, 米田 光宏², 川原 央好², 窪田 昭男², 稲村 昇³, 光田 信明¹

Shiyo OTA¹, Nobuhiro HIDAKA¹, Ryo YAMAMOTO¹, Jun SASAHARA¹, Keisuke ISHII¹, Mitsuhiro YONEDA², Hisayoshi KAWAHARA², Akio KUBOTA², Noboru INAMURA³, Nobuaki MITSUDA¹

¹大阪府立母子保健総合医療センター産科, ²大阪府立母子保健総合医療センター小児外科, ³大阪府立母子保健総合医療センター小児循環器科

¹Department of Maternal Fetal Medicine, Osaka Medical Center and Research Institute for Maternal and Child Health, ²Department of Pediatric Surgery, Osaka Medical Center and Research Institute for Maternal and Child Health, ³Department of Pediatric Cardiology, Osaka Medical Center and Research Institute for Maternal and Child Health

キーワード : congenital diaphragmatic hernia, lung to thorax transverse area ratio, postnatal prognosis, lung hypoplasia

目的：先天性左横隔膜ヘルニアにおける出生直前の超音波胎児肺胸郭断面積比（LT比）の短期予後予測因子としての有用性を検討した．対象と方法：2005年9月から2012年3月の間に当院で管理した孤発性左横隔膜ヘルニア症例を対象に，診療録より後方視的に検討した．出生直前のLT比の値0.08未満と0.08以上で対象を2群に分け，重篤な合併症なき生存退院の割合，人工換気・酸素投与期間，パッチ必要例・手術不能例の割合を両群間で比較検討した．LT比0.08未満で予後不良を予測する場合の陽性適中率，陰性適中率を算出した．LT比と生後の人工換気・酸素投与日数の相関関係を評価した．結果と考察：LT比＜0.08群に12例，LT比≧0.08群に28例が分類，計40例の対象のうち重篤な合併症なき生存退院例は34例（85％）であった．合併症なき生存退院の割合は，LT比＜0.08群で7/12（58％），LT≧0.08群で27/28（96％）であり，前者で有意に低かった．生存例における人工換気・酸素投与日数は前者で有意に長く，手術不能例・パッチ必要例は前者で有意に多かった．LT比0.08未満で予後不良例を予測する場合の陰性適中率は96％，陽性適中率は42％であった．出生直前のLT比と生後の人工換気・酸素投与日数に負の相関関係を認めた．結論：出生直前のLT比は左横隔膜ヘルニア児の短期予後の予測因子として有用である．

Purpose: In this study, we aimed to determine the clinical value of the lung to thorax transverse area ratio (LTR) as a predictive parameter of short-term postnatal outcomes in fetuses with isolated left-sided congenital diaphragmatic hernia (CDH). Subjects and Methods: Data from cases prenatally diagnosed with isolated left CDH between September 2005 and March 2012 were retrospectively collected from medical records. We divided the patients into two groups according to an LTR cutoff value of 0.08 immediately before birth. Differences in intact survival rate and duration of mechanical ventilation and supplemental oxygen were analyzed between the two groups using Fisher's exact test or the Mann-Whitney U test. The positive and negative predictive values of an LTR value < 0.08 in predicting a poor postnatal outcome were calculated. Poor outcome was defined as death or severe respiratory complications. The Spearman rank correlation was calculated to assess the correlation between LTR value and postnatal duration of ventilator support. Results and Discussion: Forty fetuses met the study criterion. The intact survival rate was significantly lower in patients with an LTR < 0.08 as compared with those with an LTR >= 0.08 (7/12 vs. 27/28). Additionally, the durations of mechanical ventilation and supplemental oxygen were significantly longer in the former group, and a negative correlation was noted between LTR values and duration of mechanical ventilatory support. When the LTR cutoff was < 0.08 for predicting a poor outcome, the positive predictive value and negative predictive value were 42% and 96%, respectively. Conclusion: The LTR was a useful predictive parameter of postnatal short-term outcomes in fetuses with isolated left CDH.