Department of Pediatrics, Division of Nephrology, Montreal Children's Hospital, McGill University Health Centre, 1001 Blvd Decarie, Room BRC.6168, Montreal, QC, H4A 3J1, Canada.
Department of Family Medicine, GMF Centre Medical Hochelaga, Montreal, QC, Canada.
Pediatr Nephrol. 2017 Oct;32(10):1953-1962. doi: 10.1007/s00467-017-3670-z. Epub 2017 May 18.
Baseline serum creatinine (bSCr) is required for diagnosing acute kidney injury (AKI). In children, bSCr is commonly defined as the lowest measurement within 3 months of admission. Measured values are often missing and estimating bSCr using height-based glomerular filtration rate (GFR) equations is problematic when height is unavailable.
This is a retrospective cohort study including 538 children admitted to the intensive care unit (ICU) between 2003 and 2005 at two centers in Canada, with measured bSCr, height, and ICU-SCr values. We evaluated the bias, accuracy, and precision of back-calculating bSCr from height-dependent and height-independent GFR equations. Agreement of AKI defined using measured and estimated bSCr was calculated. Multivariate analyses were performed to assess the impact of bSCr estimation methods on the association between AKI and ICU mortality, length of stay, and duration of mechanical ventilation.
Both methods underestimated bSCr by 1-3%, showed good accuracy (∼30% of patients with estimated bSCr within 10% of measured bSCr), but poor precision (wide 95% limits of agreement). The agreement between AKI defined by estimated versus measured bSCr was >80% (κ >0.5). The height-independent method performed best in children >13 years old; however, overall, both methods performed similarly across age subgroups. AKI was associated with longer stay, prolonged mechanical ventilation, and ICU mortality using measured and estimated bSCr.
Height-dependent and height-independent bSCr estimation methods were comparable. This may have significant implications for performing pediatric AKI research using large databases, and in clinical care to define AKI when height is unknown.
诊断急性肾损伤（AKI）需要基线血清肌酐（bSCr）。在儿童中，bSCr 通常定义为入院前 3 个月内的最低测量值。实测值经常缺失，当身高不可用时，使用基于身高的肾小球滤过率（GFR）方程估计 bSCr 是有问题的。
这是一项回顾性队列研究，纳入了 2003 年至 2005 年期间在加拿大两个中心重症监护病房（ICU）收治的 538 名儿童，他们有实测的 bSCr、身高和 ICU-SCr 值。我们评估了从基于身高和独立于身高的 GFR 方程回溯计算 bSCr 的偏倚、准确性和精度。计算了使用实测和估计 bSCr 定义的 AKI 的一致性。进行了多变量分析，以评估 bSCr 估计方法对 AKI 与 ICU 死亡率、住院时间和机械通气时间之间关联的影响。
两种方法均低估了 bSCr 约 1-3%，准确性较好（约 30%的患者估计 bSCr 与实测 bSCr 相差 10%以内），但精度较差（95%一致性界限较宽）。用估计的与实测的 bSCr 定义的 AKI 之间的一致性>80%（κ>0.5）。独立于身高的方法在>13 岁的儿童中表现最佳；然而，总体而言，两种方法在各年龄组的表现相似。使用实测和估计的 bSCr，AKI 与住院时间延长、机械通气时间延长和 ICU 死亡率相关。
基于身高和独立于身高的 bSCr 估计方法是可比的。这可能对使用大型数据库进行儿科 AKI 研究以及在临床护理中定义身高未知的 AKI 具有重要意义。
