Risk of clot formation in femoral arterial sheaths maintained overnight for neuroangiographic procedures

BACKGROUND AND PURPOSE: The purpose of this study was to evaluate the prese nce of blood clots in femoral arterial sheaths maintained after cerebral an giography and the effect of heparinized saline on clot formation. METHODS: Twenty-three sheaths were evaluated in 18 patients. Sheaths were m aintained for 14 to 80 hours (average, 33 hours; median, 24 hours). After t he sheaths were removed, they were vigorously flushed with 60 mL of normal saline and the number and size of clots found in each sheath were recorded. Additionally, patients' age, catheter size, presence of heparin, amount of time the sheath was kept in the artery, and patients' coagulation status w ere recorded. RESULTS: Clots were found in 17 (74%) of the 23 sheaths. Ten catheters had continuous heparin drip, of which seven (70%) sustained clots. Of the 13 sh eaths without heparin, 10 sustained clots (77%), The difference was not sta tistically significant. The average number of clots was 2.2, and the maxima l length of clots ranged from 0.5 to 105 mm, No thromboembolic complication s associated with sheath placement were encountered in our patient populati on. CONCLUSION: Blood clots are present in the vast majority of intraarterial s heaths maintained after cerebral angiography, These clots constitute a risk of thromboembolic complications in the event of repeat angiography, Sheath exchange should be considered before obtaining repeat cerebral angiograms.