to disruption of atherosclerotic material, with
downstream embolism. In addition, hemostasis
is much more difficult to achieve with an athero-
sclerotic vessel. This is especially problematic
for the femoral arteries, which lie deep in the
soft tissues of the groin where direct pressure
cannot be applied effectively. Massive blood
loss can occur. In consideration of these
concerns, femoral artery punctures are
discouraged.
3. At the end of the procedure, direct pressure must
be applied to the puncture site until the bleeding
has stopped. This takes at least 5 min. A much
longer time will be required for patients who are
anticoagulated or who have a bleeding disorder.
4. Thrombosis is an uncommon complication of
arterial puncture. Collateral circulation to the
hand via the ulnar artery can be confirmed using
the Allen test.
5. When the brachial artery is used as a puncture
site care must be taken to avoid the underlying
brachial nerve.
Specimen Collection Procedures A-3
