Bhardwaj Vandana, Kapoor Poonam Malhotra, Irpachi Kalpana, Ladha Suruchi, Chowdhury Ujjwal Kumar
Department of Cardiac Anaesthesia, CTC, AIIMS, New Delhi, India.
Department of CTVS, CTC, AIIMS, New Delhi, India.
Ann Card Anaesth. 2017 Jan-Mar;20(1):67-71. doi: 10.4103/0971-9784.197839.
Serum lactate and base deficit have been shown to be a predictor of morbidity and mortality in critically ill patients. Poor preoperative oxygenation appears to be one of the significant factors that affects early mortality in tetralogy of Fallot (TOF). There is little published literature evaluating the utility of serum lactate, base excess (BE), and oxygen partial pressure (PO 2 ) as simple, widely available, prognostic markers in patients undergoing surgical repair of TOF.
This prospective, observational study was conducted in 150 TOF patients, undergoing elective intracardiac repair. PO 2 , BE, and lactate levels at three different time intervals were recorded. Arterial blood samples were collected after induction (T1), after cardiopulmonary bypass (T2), and 48 h (T3) after surgery in the Intensive Care Unit (ICU). To observe the changes in PO 2 , BE, and lactate levels over a period of time, repeated measures analysis was performed with Bonferroni method. The receiver operating characteristics (ROC) analysis was used to find area under curve (AUC) and cutoff values of various biomarkers for predicting mortality in ICU.
The patients who could not survive showed significant elevated lactate levels at baseline (T1) and postoperatively (T2) as compared to patients who survived after surgery (P < 0.001). However, in nonsurvivors, the BE value decreased significantly in the postoperative period in comparison to survivors (-2.8 ± 4.27 vs. 5.04 ± 2.06) (P < 0.001). In nonsurvivors, there was a significant fall of PO 2 to a mean value of 59.86 ± 15.09 in ICU (T3), whereas those who survived had a PO 2 of 125.86 ± 95.09 (P < 0.001). The ROC curve analysis showed that lactate levels (T3) have highest mortality predictive value (AUC: 96.9%) as compared to BE (AUC: 94.5%) and PO 2 (AUC: 81.1%).
Serum lactate and BE may be used as prognostic markers to predict mortality in patients undergoing TOF repair. The routine analysis of these simple, fast, widely available, and cost-effective biomarkers should be encouraged to predict prognosis of TOF patients.
血清乳酸和碱缺失已被证明是危重症患者发病率和死亡率的预测指标。术前氧合不佳似乎是影响法洛四联症（TOF）早期死亡率的重要因素之一。关于血清乳酸、碱剩余（BE）和氧分压（PO₂）作为TOF手术修复患者简单、广泛可用的预后标志物的效用，鲜有文献发表。
本前瞻性观察性研究纳入了150例行择期心内修复术的TOF患者。记录三个不同时间点的PO₂、BE和乳酸水平。在诱导后（T1）、体外循环后（T2）以及重症监护病房（ICU）术后48小时（T3）采集动脉血样本。为观察一段时间内PO₂、BE和乳酸水平的变化，采用Bonferroni法进行重复测量分析。采用受试者工作特征（ROC）分析来确定曲线下面积（AUC）以及各种生物标志物预测ICU死亡率的临界值。
与术后存活的患者相比，未能存活的患者在基线（T1）和术后（T2）时乳酸水平显著升高（P < 0.001）。然而，与存活者相比，非存活者术后BE值显著降低（-2.8 ± 4.27 vs. 5.04 ± 2.06）（P < 0.001）。在非存活者中，ICU（T3）时PO₂显著下降至平均值59.86 ± 15.09，而存活者的PO₂为125.86 ± 95.09（P < 0.001）。ROC曲线分析表明，与BE（AUC：94.5%）和PO₂（AUC：81.1%）相比，乳酸水平（T3）具有最高的死亡率预测价值（AUC：96.9%）。
血清乳酸和BE可作为预测TOF修复患者死亡率的预后标志物。应鼓励对这些简单、快速、广泛可用且具有成本效益的生物标志物进行常规分析，以预测TOF患者的预后。
