Cobo J, Aguado J M, Cortina J, Cobo P, Martin del Hierro J L, Rufilanchas J J, Noriega A R
Unidad de Enfermedades Infecciosas, Hospital 12 de Octubre, Madrid.
Med Clin (Barc). 1996 Mar 23;106(11):401-4.
Sternal wound infection (SWI) is the most important complication in cardiac surgery. The aim of this study was to describe the frequency and clinical and microbiological features of this complication.
All the cases of SWI which were observed in the authors' hospital in the first 1,000 cardiac surgery operations performed with extracorporeal circulation were retrospectively reviewed. The cases were identified through the Infectious Diseases and Cardiac Surgery Department files and were classified according to the depth of the infection. During the study period neither the prophylaxis against infection nor the surgical techniques were modified.
Forty-three patients (4.3%) presented SWI. Fourteen were superficial infections and 29 were deep infections of which 9 were classified as osteomyelitis and 20 as mediastinitis. A progressive decrease was observed in the proportion of SWI over time parallel to an increase in the number of operations performed. Staphylococcus aureus was the agent most frequently isolated (60.4%). Gram-positive aerobic cocci were found in 66.7% of the total number of isolations, being most frequent in the deep infections (83.3% of the isolations). The gram-negative aerobic bacilli were isolated more frequently in the superficial infections than in the deep infections (57.8% v.s. 16.7% of the isolations, respectively p < 0.01). In patients with SWI the predictive value of the positive blood cultures for the diagnosis of mediastinitis was 83.3%, with a sensitivity of 50% and specificity of 91.3%. Three patients with deep infection developed chronic complications and another three died (mortality by mediastinitis 15.0%). The mean postoperative stay was 52 days for the patients with deep infection and 39 days for those with superficial infection (p = NS).
The percentage of surgical wound infection during the study period showed a trend to a decrease parallel with an increase in the number of operations. The gram-positive bacteria were responsible for most of the SWI. Although the depth of SWI is difficult to clinically predict, the presence of bacteremia suggests the existence of mediastinitis. Despite their lesser clinical importance, the superficial infections carry a long postoperative stay.
胸骨伤口感染（SWI）是心脏手术中最重要的并发症。本研究的目的是描述该并发症的发生率以及临床和微生物学特征。
回顾性分析了作者所在医院在前1000例体外循环心脏手术中观察到的所有SWI病例。通过传染病科和心脏外科的病历识别病例，并根据感染深度进行分类。在研究期间，既未改变感染预防措施，也未改变手术技术。
43例患者（4.3%）发生SWI。14例为浅表感染，29例为深部感染，其中9例分类为骨髓炎，20例为纵隔炎。随着手术数量的增加，SWI的比例呈逐渐下降趋势。金黄色葡萄球菌是最常分离出的病原体（60.4%）。革兰氏阳性需氧球菌在分离出的病原体总数中占66.7%，在深部感染中最为常见（占分离出病原体的83.3%）。革兰氏阴性需氧杆菌在浅表感染中的分离频率高于深部感染（分别为分离出病原体的57.8%和16.7%，p<0.01）。在SWI患者中，血培养阳性对纵隔炎诊断的预测价值为83.3%，敏感性为50%，特异性为91.3%。3例深部感染患者出现慢性并发症，另有3例死亡（纵隔炎死亡率为15.0%）。深部感染患者的平均术后住院时间为52天，浅表感染患者为39天（p=无显著性差异）。
研究期间手术伤口感染率呈下降趋势，与手术数量的增加平行。革兰氏阳性菌是大多数SWI的病因。虽然SWI的深度在临床上难以预测，但菌血症提示存在纵隔炎。尽管浅表感染的临床重要性较低，但术后住院时间较长。
