Aslamy Z, Dewald C L, Heffner J E
Mercy Health Services Research Group, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
Chest. 1998 Sep;114(3):820-6. doi: 10.1378/chest.114.3.820.
To determine normative values for superior vena cava (SVC) length and the utility of radiographic landmarks for identifying the boundaries of the SVC for assisting central line placement.
Cross-sectional study.
Urban tertiary care medical centers.
Patients undergoing thoracic MRI scanning for various indications.
None.
The SVC dimensions and relationship to radiographic landmarks were determined from MRI scans of 42 patients (22 men, 20 women; median age, 57 years). The median length of the SVC was 6.8 cm (range, 4.4 to 10.0 cm) and did not correlate with gender or other measured cardiovascular dimensions. The right tracheobronchial angle was the best radiographic landmark for determining the cephalad origin of the SVC being always caudad and within a median of 1.5 cm (range, 0.1 to 3.8 cm) of the upper SVC. It was always at least 2.9 cm above the atriocaval junction. The right superior heart border was formed by the left atrium in 38% (95% confidence interval, 23 to 53%) of patients and did not reliably identify the atriocaval junction.
The right tracheobronchial angle is the most reliable landmark for the upper margin of the SVC. Venous catheters placed caudad to this landmark and cephalad to the right superior cardiac silhouette or no more than 2.9 cm caudad to the tracheobronchial angle result in catheter tips within the SVC.
确定上腔静脉（SVC）长度的标准值以及影像学标志在识别SVC边界以辅助中心静脉置管方面的效用。
横断面研究。
城市三级医疗中心。
因各种适应证接受胸部MRI扫描的患者。
无。
从42例患者（22例男性，20例女性；中位年龄57岁）的MRI扫描中确定SVC的尺寸及其与影像学标志的关系。SVC的中位长度为6.8 cm（范围4.4至10.0 cm），与性别或其他测量的心血管尺寸无关。右气管支气管角是确定SVC头端起源的最佳影像学标志，总是位于SVC上部的尾侧，且与SVC上部的中位距离为1.5 cm（范围0.1至3.8 cm）。它总是比心房腔静脉交界处至少高2.9 cm。38%（95%置信区间，23%至53%）的患者右心缘由左心房构成，不能可靠地识别心房腔静脉交界处。
右气管支气管角是SVC上缘最可靠的标志。将静脉导管置于该标志的尾侧、右上心轮廓的头侧或距气管支气管角尾侧不超过2.9 cm处，可使导管尖端位于SVC内。
