Diagnostic value of compression ultrasonography and fibrinogen-related parameters for the detection of postoperative deep vein thrombosis following elective hip replacement: a pilot study.

To determine their ability to diagnose postoperative deep vein thrombosis (DVT) D-dimer - by three methods -, fibrinogen degradation products (FgDP) and fibrinogen levels were measured in 68 consecutive patients before elective surgery for hip replacement and on postoperative day 1, 3, 6, and 10. All patients received prophylaxis and underwent compression real-time B-mode ultrasonography (C-US) on postoperative day 5 and 9, and bilateral ascending venography on day 10. Twenty-two out of 68 patients developed asymptomatic postoperative DVT, which was limited to the calf veins in 14 and involved the proximal veins in 8 patients. C-US was negative in all patients on day 5. On day 9, C-US sensitivity and specificity for proximal DVT were 63% (95% confidence interval: 26%-90% and 98% (89%-100%) respectively. Postoperative changes in the laboratory parameters evaluated were not different in patients with or without DVT until day 10. On day 10, mean D-dimer, FgDP and fibrinogen levels were significantly higher in patients with DVT than in those without DVT (p values between 0.006 and 0.032), but only D-dimer was higher with DVT involving two or more venous segments than with thrombosis involving one venous segment only (p < 0.05). Stepwise logistic regression analysis identified D-dimer and fibrinogen on day 10 as predictors of postoperative DVT. In a receiver operator curve and after weighing for the coefficients generated by logistic regression analysis, the combination of a latex photometric immuno-assay and of PT-derived fibrinogen yielded-at a cut-off value of 7.0 a sensitivity of 100% (73%-100%) and a specificity of 58% (39%-75%) for DVT, with a negative predictive value of 100% (78%-100%), a positive predictive value of 52% (32%-71%) and an overall accuracy of 71% (55%-83%). These results suggest that two simple, fast and reproducible tests may permit the identification of patients at low risk of having postoperative DVT and that a combination of sensitive laboratory assays and of the highly specific C-US may select patients requiring anticoagulant treatment. Efficacy and cost-effectiveness of this approach should be evaluated in large clinical management studies.

[Use of CT-guided metal wires in pre-thoracoscopic localization of peripheral pulmonary nodules]. / Impiego dei fili metallici sotto guida con tomografia computerizzata per la localizzazione pre-toracoscopica di noduli polmonari periferici.

The recent developments in thoracic surgery have broadened the application spectrum of thoracoscopy. Video-assisted thoracoscopic lung resection is now available both to diagnose and to treat peripheral pulmonary nodules. A major factor limiting the success of thoracoscopic lung resection is the difficult localization of the pulmonary nodule. When lesions are very small and deep inside the lung, their preoperative detection may be difficult. This study was aimed at investigating the effectiveness of hookwires for CT-guided localization of peripheral pulmonary lesions requiring thoracoscopic resection. In 12 patients 12 nodules, previously detected with chest radiography, were localized with hookwires under CT guidance. Ten of 12 patients underwent thoracoscopic resection for diagnostic purposes, while the extant two patients underwent therapeutic wedge resection. In all patients prethoracoscopic hookwire positioning was successful. In 11 of 12 patients the lesion was accurately localized, while in the extant patient the wire tip was inserted deeper than the nodule. In 3 patients the wire was dislodged before surgery: in all of them a small hemorrhage developed on the visceral pleura and wedge resection was likewise possible. Four patients had a small pneumothorax which was not treated before surgery. In conclusion, percutaneous hookwire localization of peripheral lung lesions is an easy and efficacious technique and promotes thoracoscopy as a less invasive alternative to thoracotomy.