Birmingham and Tuscaloosa Health Services Research and Development Unit, Birmingham Veterans Affairs Medical Center, Birmingham, Alabama.
Department of Surgery, University of Alabama at Birmingham.
JAMA Surg. 2018 Sep 1;153(9):e182009. doi: 10.1001/jamasurg.2018.2009. Epub 2018 Sep 19.
Proteinuria indicates renal dysfunction and is a risk factor for morbidity among medical patients, but less is understood among surgical populations. There is a paucity of studies investigating how preoperative proteinuria is associated with surgical outcomes, including postoperative acute kidney injury (AKI) and readmission.
To assess preoperative urine protein levels as a biomarker for adverse surgical outcomes.
DESIGN, SETTING, AND PARTICIPANTS: A retrospective, population-based study was conducted in a cohort of patients with and without known preoperative renal dysfunction undergoing elective inpatient surgery performed at 119 Veterans Affairs facilities from October 1, 2007, to September 30, 2014. Data analysis was conducted from April 4 to December 1, 2016. Preoperative dialysis, septic, cardiac, ophthalmology, transplantation, and urologic cases were excluded.
Preoperative proteinuria as assessed by urinalysis using the closest value within 6 months of surgery: negative (0 mg/dL), trace (15-29 mg/dL), 1+ (30-100 mg/dL), 2+ (101-300 mg/dL), 3+ (301-1000 mg/dL), and 4+ (>1000 mg/dL).
Primary outcome was postoperative predischarge AKI and 30-day postdischarge unplanned readmission. Secondary outcomes included any 30-day postoperative outcome.
Of 346 676 surgeries, 153 767 met inclusion criteria, with the majority including orthopedic (37%), general (29%), and vascular procedures (14%). Evidence of proteinuria was shown in 43.8% of the population (trace: 20.6%, 1+: 16.0%, 2+: 5.5%, 3+: 1.6%) with 20.4%, 14.9%, 4.3%, and 0.9%, respectively, of the patients having a normal preoperative estimated glomerular filtration rate (eGFR). In unadjusted analysis, preoperative proteinuria was significantly associated with postoperative AKI (negative: 8.6%, trace: 12%, 1+: 14.5%, 2+: 21.2%, 3+: 27.6%; P < .001) and readmission (9.3%, 11.3%, 13.3%, 15.8%, 17.5%, respectively, P < .001). After adjustment, preoperative proteinuria was associated with postoperative AKI in a dose-dependent relationship (trace: odds ratio [OR], 1.2; 95% CI, 1.1-1.3, to 3+: OR, 2.0; 95% CI, 1.8-2.2) and 30-day unplanned readmission (trace: OR, 1.0; 95% CI, 1.0-1.1, to 3+: OR, 1.3; 95% CI, 1.1-1.4). Preoperative proteinuria was associated with AKI independent of eGFR.
Proteinuria was associated with postoperative AKI and 30-day unplanned readmission independent of preoperative eGFR. Simple urine assessment for proteinuria may identify patients at higher risk of AKI and readmission to guide perioperative management.
重要性：蛋白尿表明肾功能障碍，是医疗患者发病的一个风险因素，但在外科人群中了解较少。很少有研究调查术前蛋白尿与手术结果的关系，包括术后急性肾损伤（AKI）和再入院。
目的：评估术前尿蛋白水平作为不良手术结果的生物标志物。
设计、地点和参与者：在 2007 年 10 月 1 日至 2014 年 9 月 30 日期间，在 119 个退伍军人事务设施中进行的一项基于人群的回顾性研究，纳入了接受择期住院手术的已知术前肾功能障碍患者和无肾功能障碍患者。数据分析于 2016 年 4 月 4 日至 12 月 1 日进行。排除术前透析、感染性、心脏、眼科、移植和泌尿科病例。
暴露：使用手术前 6 个月内最接近的值进行尿液分析评估术前蛋白尿：阴性（0 mg/dL）、微量（15-29 mg/dL）、1+（30-100 mg/dL）、2+（101-300 mg/dL）、3+（301-1000 mg/dL）和 4+（>1000 mg/dL）。
主要结果和措施：主要结局是术后出院前 AKI 和术后 30 天非计划性再入院。次要结局包括任何术后 30 天的结果。
结果：在 346676 例手术中，有 153767 例符合纳入标准，其中大多数为骨科（37%）、普通外科（29%）和血管手术（14%）。人群中有 43.8%的人有蛋白尿的证据（微量：20.6%，1+：16.0%，2+：5.5%，3+：1.6%），分别有 20.4%、14.9%、4.3%和 0.9%的患者术前肾小球滤过率（eGFR）正常。在未调整分析中，术前蛋白尿与术后 AKI（阴性：8.6%，微量：12%，1+：14.5%，2+：21.2%，3+：27.6%；P<.001）和再入院（9.3%，11.3%，13.3%，15.8%，17.5%，分别，P<.001）显著相关。调整后，术前蛋白尿与术后 AKI 呈剂量依赖性关系（微量：比值比[OR]，1.2；95%CI，1.1-1.3，至 3+：OR，2.0；95%CI，1.8-2.2）和 30 天非计划性再入院（微量：OR，1.0；95%CI，1.0-1.1，至 3+：OR，1.3；95%CI，1.1-1.4）。术前蛋白尿与 AKI 独立于 eGFR 相关。
结论和相关性：蛋白尿与术后 AKI 和 30 天非计划性再入院独立于术前 eGFR 相关。简单的尿蛋白评估可能可以识别 AKI 和再入院风险较高的患者，从而指导围手术期管理。
