FitzSullivan Elizabeth, Salim Ali, Demetriades Demetrios, Asensio Juan, Martin Matthew J
Division of Trauma and Surgical Critical Care, Keck School of Medicine, University of Southern California and the Los Angeles County + USC Medical Center, 1200 North State Street, Room 10-750, Los Angeles, CA 90033, USA.
Am J Surg. 2005 Dec;190(6):941-6. doi: 10.1016/j.amjsurg.2005.08.024.
Arterial base deficit (BD) is a commonly used marker of injury severity and endpoint of resuscitation but requires an arterial puncture and blood gas analysis. Serum bicarbonate (HCO3) is routinely obtained as part of the chemistry panel on most admissions. We hypothesized that serum HCO3 strongly correlates with arterial BD and provides equivalent predictive information.
All trauma ICU admissions from 1996 to 2004 with simultaneously obtained serum chemistry panels and arterial blood gases were identified. Correlation between BD and HCO3 was analyzed by using linear regression, and predictive abilities for acidoses and mortality were compared using the area under the respective receiver operating characteristic curve (AUC). Separate analyses were done for the entire dataset and the subset of ICU admission laboratory values.
We identified 3,102 patients with 50,311 matched pairs of laboratory data. Serum HCO3 showed a significant linear correlation with BD for all laboratory sets (r = 0.85, P < .01) and admission laboratory values only (r = 0.80, P < .01). Serum HCO3 reliably predicted the presence of significant metabolic acidoses (BD >5), with an AUC of 0.96 (P < .01), which clearly outperformed pH (AUC = 0.83), anion gap (AUC = 0.7), and lactate (AUC = 0.73). The mean admission BD among survivors was 2.5 versus 5.2 for nonsurvivors (P < .01), and the mean HCO3 was 17.7 versus 19.8 (P < .01). The admission HCO3 identified nonsurvivors as accurately as BD (AUCs of 0.66 and 0.68) and more accurately than either pH (AUC = 0.53) or anion gap (AUC = 0.6).
Serum HCO3 measurement shows a strong linear correlation and similar predictive ability compared with the arterial BD. Serum HCO3 may be safely and accurately substituted for arterial BD measurement in critically injured patients.
动脉碱缺失（BD）是常用的损伤严重程度指标和复苏终点，但需要进行动脉穿刺和血气分析。血清碳酸氢盐（HCO3）在大多数入院患者的生化检查中常规获取。我们假设血清HCO3与动脉BD密切相关，并能提供同等的预测信息。
确定1996年至2004年所有入住创伤重症监护病房（ICU）且同时获得血清生化检查结果和动脉血气的患者。采用线性回归分析BD与HCO3之间的相关性，并使用各自的受试者工作特征曲线（AUC）下的面积比较对酸中毒和死亡率的预测能力。对整个数据集和ICU入院实验室值子集进行单独分析。
我们确定了3102例患者，有50311对匹配的实验室数据。血清HCO3与所有实验室组的BD均呈显著线性相关（r = 0.85，P <.01），仅与入院实验室值相关时（r = 0.80，P <.01）。血清HCO3能可靠地预测显著代谢性酸中毒（BD >5）的存在，AUC为0.96（P <.01），明显优于pH（AUC = 0.83）、阴离子间隙（AUC = 0.7）和乳酸（AUC = 0.73）。幸存者的平均入院BD为2.5，非幸存者为5.2（P <.01），平均HCO3分别为17.7和19.8（P <.01）。入院时的HCO3识别非幸存者的准确性与BD相当（AUC分别为0.66和0.68），比pH（AUC = 0.53）或阴离子间隙（AUC = 0.6）更准确。
血清HCO3测量与动脉BD相比显示出强线性相关性和相似的预测能力。在重症受伤患者中，血清HCO3可安全准确地替代动脉BD测量。
