Simplified phlebography in deep venous thrombosis

A comprehensive review of vascular ultrasound for intensivists

Ultrasound has an increasingly important role in evaluation of the vascular system. Ultrasound is especially useful for intensive care patients because of the frequency of vascular complications developing in the ICU setting, as well as the ability of ultrasound to be performed at the patient's bedside. Ultrasound is the method of choice for evaluation of deep vein thromboembolic disease of the lower extremity in all patients; it demonstrates excellent sensitivity and specificity for this condition. It should also be the initial method of evaluation of upper extremity deep vein thrombosis. However, ultrasound may be limited in this assessment due to lack of reliably demonstrating the central subclavian and innominate veins, and therefore may be inadequate for evaluation of malfunctioning central venous catheters. Ultrasound can reliably identify and potentially be used to treat arterial complications of arterial catheterization, such as pseudoaneurysms. Similarly, ultrasound is accurate in the diagnosis of the presence of abdominal aortic aneurysm, and ultrasound can be used to assess carotid and lower extremity arteries noninvasively. Finally, ultrasound is useful for evaluation of hemodialysis fistulas and vascular complications of transplants.

Contrast agent induced thrombophlebitis following leg phlebography: iopamidol versus meglumine iothalamate

A comparison was made of the incidence of venous thrombophlebitis resulting from the use of a high-osmolality contrast medium (Conray 60%, meglumine iothalamate), and a low-osmolality contrast medium (Niopam 61%, iopamidol). In 20 patients Conray was injected into one leg and Niopam into the other. The incidence of thrombophlebitis was then determined using the iodine-125 fibrinogen uptake test in a prospective, randomised, double-blind study. There was significantly less thrombophlebitis with Niopam than with Conray and it is concluded that Niopam is a safer contrast medium for phlebography.

Temporary transvenous pacing and femoral vein thrombosis

The true incidence of thrombosis and pulmonary embolism in patients requiring temporary transvenous pacing via the femoral vein in unknown. Twenty-nine patients, mean age 66.2 years (range 38-79 years) who required temporary pacing were studied by bilateral contrast venography and perfusion lung scanning after removal of the pacing catheter. The patients were subdivided into two subgroups based on hemodynamic status. There was no statistical difference between the two groups with respect to mean age or the time the pacer catheter was in place and all patients were placed on low-dose heparin therapy. Ten patients (34%) had venographic evidence of thrombosis; six of them (60%) showed lung scan evidence of pulmonary emboli. The hemodynamically compromised group consisted of seven patients, six (85%) of whom had thrombosis; three of these six (50%) had pulmonary emboli. Of the 22 patients in the hemodynamically stable group, four (18%) had thrombosis and two of these (50%) had pulmonary emboli. Venous thrombosis, with subsequent pulmonary emboli, is a serious complication of temporary transvenous pacing using the femoral approach, despite the use of prophylactic low-dose heparin.

Thrombosis after phlebography: a comparison of two contrast media

In two studies 267 consecutive patients with suspected leg vein thrombosis were examined by an 125I-fibrinogen uptake test (125I-FUT) and by phlebography. The ionic meglumine calcium metrizoate (Isopaque Cerebral) was used as the phlebographic contrast medium in 161 patients, and the non-ionic metrizamide (Amipaque) was used in 106. In these two groups 47 and 41 patients, respectively, had normal phlebograms as well as an initially normal 125I-FUT. After phlebography 29 (62%) of the patients who had received meglumine metrizoate had a significant rise in fibrinogen uptake, while such a rise was not found in patients examined with metrizamide. Repeat phlebography showed fresh deep-vein thrombosis in seven of the nine patients with increased uptake, indicating a complication rate of 48%. Consequently, we now use metrizamide in leg phlebogrphy; because of its expense a radioisotope test is employed as a screening procedure.

Complications of ascending phlebography of the leg

Forty patients were studied prospectively for complications of ascending phlebography. The commonest immediate complication was pain at the site of injection and the commonest delayed complication pain in the foot or calf. Out of 30 patients with pain in the foot and calf, 15 had venous thrombosis. Review of 200 case notes disclosed only one recorded complication--namely, necrosis of the dorsal skin of the foot. Complications of the procedure reported by referring clinicians over 10 years comprised four cases of necrosis of the dorsum of the foot and two of gangrene of the foot, in one of which the gangrene spread to the leg. Major complications of ascending phlebography are rare, though when they occur may cause serious morbidity. If a scrupulous technique is used contrast phlebography remains the most accurate method of diagnosing venous disease of the leg.

After-exercise thermography for predicting postoperative deep vein thrombosis

After-exercise thermography of the legs was carried out on 50 patients before undergoing major abdominal surgery (group 1) and on 59 patients before elective hip surgery (group 2). The incidence of postoperative deep vein thrombosis (DVT)--diagnosed by the 125I-fibrinogen uptake test in group 1 and phlebography in group 2--was significantly higher in patients whose after-exercise thermogram (AET) had been abnormal. Out of 19 patients in group 1 and 30 in group 2 with a normal AET, two and nine repsectively developed postoperative DVT. Among patients with a unilaterally abnormal AET the incidences were 12 out of 19 patients in group 1 and five out of nine in group 2. The incidences among patients with a bilaterally abnormal AET rose to 11 out of 12 patients in group 1 and 15 out of 20 in group 2. Preoperative after-exercise thermography is a simple, objective test that identifies patients at high risk of developing postoperative thromboembolic disease.

Intravenous lignocaine in prevention of deep venous thrombosis after elective hip surgery

Intravenous lignocaine is a possible means of preventing deep venous thrombosis (D.V.T.) after elective hip surgery. In 14 control patients the total incidence of D.V.T. was 78%, with a 57% incidence of thigh-vein thrombosis. In 14 patients treated at random with intravenous lignocaine during the first 6 postoperative days, there were only 2 calf-vein thrombi (14%; P less than 0-005). In a further 14 cases treated consecutively there were 4 unilateral calf-vein thrombi. No thrombi originated in the thigh veins (P less than 0-001). After intravenous lignocaine was stopped the total incidence of D.V.T. in the 28 patients rose to 53% with a 21% incidence of thigh-vein thrombi between the 7th and 14th postoperative days. There was no significant difference in postoperative coagulation and fibrinolytic activity between control and treated patients, and blood loss and transfusion requirements were similar. Immediate or delayed hypersensitivity reactions to lignocaine were not observed. The results support the view that damage to the vessel wall may be the initial event in the formation of a venous thrombus.

The accuracy of bolus ascending phlebography in demonstrating the ilio-femoral segment

The phlebograms of the ilio-femoral segment obtained by a bolus technique in 100 patients were reviewed. The technique of bolus phlebography from bipedal injections is described in detail. In 92% of the phlebograms the ilio-femoral segment was considered to be sufficiently well opacified to exclude thrombus. Follow-up of the patients confirmed the accuracy of the method.

Comparison of 125I-labelled fibrinogen uptake and venography in the detection of recent deep-vein thrombosis in the legs

Both techniques were used to examine 72 legs, and agreed about the presence or absence of thrombus in 54 cases (72 per cent). In 41 legs both tests were positive and in 13 legs both tests were negative. In 16 legs the 125I fibrinogen test only was positive, and if the seven legs with clinical conditions known to increase fibrinogen uptake are excluded, there were nine legs (13 per cent) with an increased fibrinogen uptake in the calf and a normal venogram. In two legs the venogram only was positive, and in both cases there was evidence of clot retraction which suggested that the thrombus was more than a week old. The use of radio-opaque markers attached to the skin made it possible to compare the site of thrombosis detected by the two techniques and the results of this comparison indicate that the fibrinogen test underestimated the extent of femoral vein thrombosis in a significant proportion of cases. (p less than 0-001).

Successful treatment of ileofemoral venous thrombosis following cardiac catheterization

Whittaker, M., and Kerr, R. V. (1973).Thorax, 28, 794-796. Successful treatment of ileofemoral venous thrombosis following cardiac catheterization. This paper describes a case of ileofemoral venous thrombosis following transseptal cardiac catheterization. The diagnosis was established by phlebography and early venous thrombectomy was successfully performed.

Pulmonary perfusion defects in postoperative chest infections

The repeated demonstration by many workers that there is a high incidence of asymptomatic postoperative lower limb venous thrombosis suggests that pulmonary embolism is likely to be a more frequent occurrence than is commonly accepted. If this assumption is correct then many emboli must be asymptomatic or producing atypical symptoms.

The incidence of pulmonary artery perfusion defects in 50 general surgical patients who developed postoperative chest complications has been investigated by radioisotope scanning of the lungs. Nine of 10 patients considered on clinical grounds to have had a pulmonary embolus were shown on pulmonary scanning to have perfusion defects which would support such a diagnosis.

Of the 40 patients diagnosed as having postoperative chest infections, perfusion defects in the lung scan were present in 33. In 19 of these 33 the perfusion defect was associated with an inflammatory lesion or an abnormal position of the diaphragm, visible on the chest radiograph. However, in 7 of the 19 patients the size of the perfusion defect seemed disproportionately large when compared with the extent of the lesion visible on the chest radiograph.

In the remaining 14 patients the perfusion defects were not associated with any abnormality visible on the chest radiograph. It is considered that the perfusion defects in these 14 cases together with those in the seven cases in which the defect was disproportionately large represent `silent' pulmonary emboli.

It is suggested that pulmonary scanning carried out in cases of persistent postoperative chest infection will reveal, in many instances, a perfusion defect indicative of the presence of an underlying pulmonary embolus. In some cases this will be the precursor of a more major embolus.