探讨烧伤患者发生中心静脉导管(CVC)的导管相关性血流感染(CRBSI)的危险因素。

前瞻性选择武汉大学同仁医院暨武汉市第三医院烧伤科2016年1月至2017年12月收治住院的烧伤患者，收集置管患者例数、置管例次、性别、年龄、置管血管种类、是否经创面置管、导管留置时间、烧伤面积以及统计CRBSI发生率，分析CRBSI的影响因素。数据比较采用Mann-Whitney U检验、卡方检验或Fisher确切概率法分析，2组间多重比较采用Bonferroni校正P值，采用二元logistic回归分析对CRBSI的影响因素进行多因素分析。绘制入选样本导管留置时间的受试者工作特征曲线。

符合入选标准的烧伤患者共112例，218例次置管，平均每人置管(2.0±1.7)次；其中男91例，180例次(82.6%)置管，女21例，38例次(17.4%)置管；患者年龄7.0~74.0岁，平均年龄(45.4±13.0)岁；置管血管包括颈内静脉11例次、锁骨下静脉29例次、股动脉67例次及股静脉111例次。经创面置管130例(59.6%)，经正常皮肤置管88例(40.4%)；218例次导管留置时间2.0~48.0 d，平均置管时间(14.8±7.6)d，导管留置总时长3 224个导管日；烧伤面积范围为10.0%~99.0%总体表面积(TBSA)，平均烧伤面积(67.7±23.3)%TBSA；发生CRBSI共32例次，总发生率14.7%，发生CRBSI的每千导管日感染发生率9.9‰。发生CRBSI感染的患者平均置管(3.7±3.4)例次与未发生CRBSI感染的患者平均(1.7±1.1)例次比较，差异有统计学意义(Z＝4.406，P<0.001)；男性患者CRBSI发生率14.4%(26/180)、女性患者15.8%(6/38)，比较差异无统计学意义(χ²＝0.045，P＝0.831)。发生CRBSI感染的患者平均年龄(44.4±12.1)岁，与未发生CRBSI感染的患者平均年龄(45.6±13.2)岁比较，差异无统计学意义(Z＝0.451，P＝0.652)。不同种类的置管血管CRBSI发生率分别为颈内静脉27.3%(3/11)、锁骨下静脉24.1%(7/29)、股动脉14.9%(10/67)、股静脉10.8%(12/111)，比较差异无统计学意义(χ²＝4.396，P＝0.222)。经正常皮肤和创面置管的CRBSI发生率分别为8.0%(7/88)和19.2%(25/130)，比较差异有统计学意义(χ²＝5.328，P＝0.021)；随导管留置时间的延长，CRBSI发生率显著增加，比较差异有统计学意义(χ²＝21.151，P＝0.001)，其中导管留置6~10 d、11~15 d、16~20 d的患者CRBSI发生率分别为8.8%、11.4%、10.8%，均显著低于导管留置26~48 d患者的57.1%，差异均有统计学意义(χ²＝14.496、12.986，P<0.05)；根据本研究数据，预测CRBSI的导管留置时间受试者工作特征曲线下面积为0.696(95%CI：0.584~0.808，P<0.001)，得到约登指数最大的导管安全留置时间为22 d，其灵敏度为46.9%，特异度为91.4%；随着烧伤面积增大，CRBSI发生率显著增加，比较差异有统计学意义(χ²＝15.911，P＝0.003)，其中烧伤面积41%~60%TBSA的患者CRBSI发生率为3.9%，显著低于烧伤面积81%~99%TBSA患者的24.3%，差异有统计学意义(P＝0.020)；影响CRBSI的危险因素logistic回归分析结果显示，烧伤面积及导管留置时间为CRBSI的独立危险因素[比值比＝[1.031(95%CI：1.008~1.054)，P＝0.008；比值比＝1.109(95%CI：1.052~1.169)，P<0.001]。

经创面置管CRBSI发生率高于经正常皮肤置管；烧伤面积和导管留置时间是CRBSI独立危险因素；置管超过22 d发生CRBSI的可能性明显增高。

To study the risk factors of catheter-related bloodstream infection(CRBSI) with central venous catheters(CVC) in burn patients.

The burn patients admitted to Department of Burns, Tongren Hospital of Wuhan University & Wuhan Third Hospital from January 2016 to December 2017 were prospectively selected, and collected the number of catheterized patients, number of catheterization cases, gender, age, the types of catheterization vessels, whether the catheters was inserted through the wound, the catheter indwelling time, the burn area and the incidence of CRBSI, analyzed the influencing factors of CRBSI. Data comparisons were analyzed by Mann-Whitney U test, chi-square test or Fisher exact probability method. Multiple comparisons between the two groups were analyzed by Bonferroni-corrected P value, and binary logistic regression analysis was used to analyze the influencing factors of CRBSI. Draw the receiver operating characteristic curve of the catheter indwelling time of the selected samples.

A total of 112 patients with burns who met the inclusion criteria were intubated with 218 catheterizations, with an average of (2.0±1.7) times catheterizations per person; among them, 91 were males, 180 times (82.6%) were catheterized, and 21 were females, with 38 times (17.4%) catheterizations; the patients were 7.0 to 74.0 years old, with an average age of (45.4±13.0) years old; the catheterization vessels included 11 cases of internal jugular vein, 29 cases of subclavian vein, 67 cases of femoral artery and 111 cases of femoral vein. One hundred and thirty cases (59.6%) were catheterized through the wound and 88 cases (40.4%) were catheterized through normal skin; in 218 cases, the catheter indwelling time was 2.0 to 48.0 days, the average catheter indwelling time was (14.8±7.6) days, and the total catheter indwelling time was 3 224 catheter days; the burn area ranged from 10.0% to 99.0% total body surface area (TBSA), and the average burn area was (67.7±23.3)% TBSA; a total of 32 cases of CRBSI occurred, and the total incidence was 14.68%, the infection rate per thousand catheter day of CRBSI was 9.9‰. Compared with the average (3.7±3.4) cases of patients with CRBSI infection and the average (1.7±1.1) cases of patients without CRBSI infection, the difference was statistically significant (Z=4.406, P<0.001); the CRBSI incidence of male patients was 14.4% (26/180) and which was 15.8% (6/38) of female patients, the difference was not statistically significant (χ²=0.045, P=0.831). The average age of patients with CRBSI infection was (44.4±12.1) years old, compared with the average age of patients without CRBSI infection (45.6±13.2) years old, the difference was not statistically significant (Z=0.451, P=0.652). The CRBSI incidences of different types of catheterization vessels was 27.3% (3/11) in the internal jugular vein, 24.1% (7/29) in the subclavian vein, 14.9% (10/67) in the femoral artery, and 10.8% in the femoral vein (12/111), respectively, and the differences were not statistically significant (χ²=4.396, P=0.222). The incidence of CRBSI for catheter placement through normal skin and wound surface was 8.0% (7/88) and 19.2% (25/130), respectively, and the difference was statistically significant (χ²=5.328, P=0.021); with the extension of catheter indwelling time, the incidence of CRBSI increased significantly, and the difference was statistically significant (χ²=21.151, P=0.001). The incidence of CRBSI was 8.8%, 11.4%, and 10.8% in patients with indwelling catheters for 6-10 days, 11-15 days, and 16-20 days, respectively, which were significantly lower than 57.1% of patients with catheter indwelling for 26-48 days, the difference were statistically significant (χ²=14.496, 12.986; P<0.05); according to the data of this study, the area under the curve of the catheter indwelling time of CRBSI was 0.696 (95%CI: 0.584-0.808, P<0.001), and the catheter indwelling time with the largest Jordan index was 22 days and with the sensitivity of 46.9% and the specificity of 91.4%. With the increase of burn area, the incidence of CRBSI increased significantly, and the difference was statistically significant (χ²=15.911, P=0.003). Among them, the incidence of CRBSI in patients with burn area of 41%-60% TBSA was 3.9%, which was significantly lower than that of 24.3% of patients with burn area of 81%-99% TBSA, the difference was statistically significant (P=0.020). The logistic regression analysis of risk factors affecting CRBSI showed that burn area and catheter indwelling time were independent risk factors for CRBSI {odds ratio=[1.031 (95%CI: 1.008-1.054), P=0.008; odds ratio=1.109 (95%CI: 1.052-1.169), P<0.001}.

The CRBSI incidence in the wound is higher than that in the normal skin; the total burn area and catheter indwelling time are independent risk factors for CRBSI; the possibility of CRBSI occurring after catheterization for more than 22 days is significantly higher.