Imai Takehide, Takase Masato
Department of Pediatrics, Nippon Medical School Tama Nagayama Hospital.
J Nippon Med Sch. 2015;82(4):180-5. doi: 10.1272/jnms.82.180.
Measurement of interrupter airway resistance (Rint) is a convenient alternative to standard spirometry for assessing respiratory function in uncooperative young children. The aim of the present prospective study was to establish the normative data and predictive equation of Rint in Japanese preschool children. A total of 214 children were enrolled from a single kindergarten; however, 129 were excluded because they met at least 1 of the exclusion criteria, such as wheezing history or recent common cold. Expiratory Rint values were assessed in 85 of the children, but technically unsatisfactory measurements were obtained in 5 of them. Thus, 80 healthy Japanese children (39 boys and 41 girls) without any history or symptoms of respiratory tract diseases were evaluated. Their age, body height, and body weight ranges (median) were 1.67 to 6.42 (4.38) years, 79.8 to 120.9 (102.5) cm, and 10.4 to 24.9 (15.8) kg, respectively. The mean Rint was 0.93±0.25 kPa/L/s (range=0.46-1.49 kPa/L/s). The Rint tended to decrease with increasing age and body height (r=-0.65; P<0.01), but sex played no significant role (P=0.71). The predictive equation based on body height derived by linear regression was expiratory Rint (kPa/L/s) =2.513-0.01567×body height (cm) (multiple correlation coefficient=0.653). Because 79 of the 80 measured Rint values were within 140% of the predictive Rint value, we calculated a 140% cut-off for predicting bronchoconstriction. Our results provide a reference value for evaluating the degree of airway obstruction in young Japanese children.
测量阻断气道阻力（Rint）是评估不合作幼儿呼吸功能的一种方便替代标准肺活量测定法的方法。本前瞻性研究的目的是建立日本学龄前儿童Rint的正常数据和预测方程。从一所幼儿园共招募了214名儿童；然而，129名儿童因符合至少一项排除标准（如喘息病史或近期患普通感冒）而被排除。对85名儿童进行了呼气Rint值评估，但其中5名儿童的测量结果在技术上不令人满意。因此，对80名无任何呼吸道疾病病史或症状的健康日本儿童（39名男孩和41名女孩）进行了评估。他们的年龄、身高和体重范围（中位数）分别为1.67至6.42（4.38）岁、79.8至120.9（102.5）厘米和10.4至24.9（15.8）千克。平均Rint为0.93±0.25千帕/升/秒（范围=0.46 - 1.49千帕/升/秒）。Rint倾向于随年龄和身高增加而降低（r = -0.65；P < 0.01），但性别无显著作用（P = 0.71）。通过线性回归得出的基于身高的预测方程为呼气Rint（千帕/升/秒）= 2.513 - 0.01567×身高（厘米）（复相关系数 = 0.653）。由于80个测量的Rint值中有79个在预测Rint值的140%以内，我们计算了预测支气管收缩的140%临界值。我们的结果为评估日本幼儿气道阻塞程度提供了参考值。
