Department of Cardiovascular Surgery, Mayo Clinic Rochester, Minnesota.
Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota.
Ann Thorac Surg. 2021 Jul;112(1):91-98. doi: 10.1016/j.athoracsur.2020.08.030. Epub 2020 Oct 17.
Hyponatremia is an unrecognized risk factor for adverse outcomes after cardiac surgery. We sought to study the prevalence of preoperative hyponatremia and its impact on short-term and long-term outcomes after cardiac surgery.
Patients who had coronary artery bypass graft, valve, or coronary artery bypass graft and valve procedures from 2000 to 2016 and available preoperative serum sodium values within 30 days of the index procedure were included in the study. The effect of preoperative sodium on short-term and long-term outcomes was analyzed as a continuous and binary (hyponatremia [Na+ <135 mEq/L] versus no hyponatremia) predictor variable in multivariable regression models.
Preoperative hyponatremia was present in 9.9% of 16,238 patients with available sodium levels. Comorbidities were more common in patients with hyponatremia. Hyponatremia was independently associated with operative mortality (odds ratio [OR] = 1.80; 95% confidence interval [CI], 1.38-2.34; P < .001), long-term mortality (hazard ratio = 1.31; 95% CI, 1.21-1.40; P < .001), longer postoperative length of stay (hazard ratio = 1.35; 95% CI, 1.28-1.43; P < .001), renal failure (OR = 1.52; 95% CI, 1.20-1.93; P < .001), prolonged ventilation use (OR = 1.52; 95% CI, 1.30-1.78; P < .001), and stroke or transient ischemic attack (OR = 1.48; 95% CI, 1.09-2.02; P = .013). Severity of hyponatremia, as measured by sodium level, was similarly associated with increased risk for death and postoperative complications.
Preoperative hyponatremia is relatively common and is associated with adverse short-term and long-term outcomes after cardiac surgery. Preoperative hyponatremia can be used independently from standard risk factors to identify high-risk patients for cardiac surgery.
低钠血症是心脏手术后不良结局的一个未被认识到的危险因素。我们旨在研究术前低钠血症的发生率及其对心脏手术后短期和长期结局的影响。
本研究纳入了 2000 年至 2016 年期间接受冠状动脉旁路移植术、瓣膜手术或冠状动脉旁路移植术联合瓣膜手术且术前 30 天内有血清钠值的患者。采用多变量回归模型，将术前钠水平作为连续和二分类（低钠血症 [Na+ <135 mEq/L] 与非低钠血症）预测变量来分析其对短期和长期结局的影响。
在有钠水平可用的 16238 例患者中，术前低钠血症的发生率为 9.9%。低钠血症患者的合并症更为常见。低钠血症与手术死亡率（比值比 [OR] 1.80；95%置信区间 [CI]，1.38-2.34；P <.001）、长期死亡率（风险比 [HR] 1.31；95% CI，1.21-1.40；P <.001）、术后住院时间延长（HR 1.35；95% CI，1.28-1.43；P <.001）、肾衰竭（OR 1.52；95% CI，1.20-1.93；P <.001）、延长机械通气时间（OR 1.52；95% CI，1.30-1.78；P <.001）和卒中和短暂性脑缺血发作（OR 1.48；95% CI，1.09-2.02；P =.013）相关。低钠血症的严重程度（以钠水平衡量）与死亡和术后并发症风险增加也存在相关性。
术前低钠血症较为常见，与心脏手术后的短期和长期不良结局相关。术前低钠血症可独立于标准危险因素，用于识别心脏手术的高危患者。
