General risk factors:
(1) decreased elasticity of the arterial wall
(2) large opening in the arterial wall
(3) coagulopathy
(4) hypertension
Decreased elasticity of the arterial wall:
(1) elderly patients (age-related)
(2) hereditary connective tissue disease (Ehlers-Danlos syndrome, etc.)
(3) theoretically underlying vascular disease like atherosclerosis or aneurysm, but these are unusual in sites selected for blood gas collection (except perhaps the femoral artery)
(4) high dose corticosteroid therapy can affect wound healing and in theory could affect closure of the defect
Size of opening in arterial wall:
(1) based on needle size (20-25 gauge needle acceptable, with smallest possible gauge preferred in the patient with other risk factors)
(2) traumatic technique with tearing of arterial wall
Coagulopathy:
(1) patient receiving coumadin or heparin (anticoagulated)
(2) hereditary or acquired coagulopathy
Management options in the patient at risk:
(1) Defer the procedure if possible. Select the most easily accessible and least disease site.
(2) Use the smallest possible needle gauge
(3) The specimen should be collected by an experienced person.
(4) If on an extremity, raise the limb if possible. Apply pressure to the site for a prolonged period.
(5) Apply an occlusive dressing.
(6) Monitor the site (or instruct the patient to) for hematoma formation.
