Subramaniam Rathan M, Chou Tina, Heath Rebekah, Allen Robin
Academic and Research Division, Department of Radiology, Waikato Hospital, Hamilton, New Zealand.
AJR Am J Roentgenol. 2006 Jan;186(1):206-12. doi: 10.2214/AJR.04.1398.
The purpose of our study was to develop and validate a clinical score (the Hamilton score) for the assessment of lower limb deep venous thrombosis (DVT) and to determine the usefulness of this score and a D-dimer assay before a complete lower limb sonographic examination.
Five hundred forty-two consecutive ambulatory patients presenting to the emergency department were prospectively recruited, of whom 16 patients were excluded from the study. Eighteen history and examination variables were collected by the emergency department physicians. The Simplify D-dimer assay and a complete, single lower limb sonographic examination were performed in all patients. All patients with a negative sonographic examination for DVT were followed up for 3 months, and all those with a positive sonographic examination were given anticoagulation therapy. The Hamilton score was developed using the data from the first 214 patients and was prospectively validated in the next 312 patients.
The most significant factors associated with a diagnosis of DVT were immobilization of the lower limb, active malignancy, and a strong clinical suspicion of DVT without other diagnostic possibilities by the emergency department physicians. Other factors were bed rest or recent surgery, male sex, calf circumference difference greater than 3 cm, and erythema. The Hamilton score was developed with the following weights: immobilization of the lower limb (2 points), active malignancy (2 points), strong clinical suspicion of DVT without other diagnostic possibilities by the emergency physicians (2 points), bed rest or recent surgery (1 point), male sex (1 point), calf circumference difference greater than 3 cm (1 point), and erythema (1 point). A score of 3 or greater indicates a likely probability for DVT, and a score of 2 or less represents an unlikely probability for DVT. Of the 103 patients with an unlikely probability Hamilton score and a negative D-dimer assay, only one patient had isolated calf DVT. A combined diagnostic strategy of unlikely-probability Hamilton score and a negative D-dimer would have a negative predictive value of 99% (95% confidence interval, 94.7-100%).
An unlikely-probability Hamilton score and a negative Simplify D-dimer assay effectively exclude lower limb DVT, and a sonographic examination is unnecessary in this group of ambulatory emergency department patients.
本研究的目的是开发并验证一种用于评估下肢深静脉血栓形成（DVT）的临床评分（汉密尔顿评分），并确定该评分及D-二聚体检测在完整下肢超声检查前的效用。
前瞻性招募了542例连续到急诊科就诊的门诊患者，其中16例被排除在研究之外。急诊科医生收集了18项病史和检查变量。所有患者均进行了简化D-二聚体检测及完整的单下肢超声检查。所有超声检查DVT阴性的患者随访3个月，所有超声检查阳性的患者均接受抗凝治疗。汉密尔顿评分利用前214例患者的数据制定，并在前瞻性研究中对接下来的312例患者进行验证。
与DVT诊断相关的最显著因素为下肢制动、活动性恶性肿瘤以及急诊科医生强烈怀疑DVT但无其他诊断可能。其他因素包括卧床休息或近期手术、男性、双侧小腿周径差大于3 cm以及红斑。汉密尔顿评分的权重如下：下肢制动（2分）、活动性恶性肿瘤（2分）、急诊科医生强烈怀疑DVT但无其他诊断可能（2分）、卧床休息或近期手术（1分）、男性（1分）、双侧小腿周径差大于3 cm（1分）以及红斑（1分）。评分3分或更高表明DVT可能性大，评分2分或更低表明DVT可能性小。在汉密尔顿评分可能性小且D-二聚体检测阴性的103例患者中，仅1例有孤立性小腿DVT。汉密尔顿评分可能性小且D-二聚体检测阴性的联合诊断策略阴性预测值为99%（95%置信区间，94.7 - 100%）。
汉密尔顿评分可能性小且简化D-二聚体检测阴性可有效排除下肢DVT，对于这类门诊急诊科患者无需进行超声检查。
