Which of the following statements about iatrogenic arterial injuries are true?

B. Symptomatic axillary sheath hematomas require urgent operative intervention.

D. The Allen test identifies patients with an incomplete palmar arch.

DISCUSSION: Small pseudoaneurysms after arterial puncture often close spontaneously. Duplex-guided compression may be used to cause thrombosis of the pseudoaneurysm. Surgery is usually reserved for large or expanding pseudoaneurysms that are not successfully occluded by duplex-guided compression. On the other hand, axillary sheath hematomas can cause permanent nerve injury and require urgent surgical decompression. Occlusions after catheterization are more common in smaller arteries such as the brachial artery, but ischemic signs and symptoms are more likely with larger vessel occlusions. The Allen test should be performed before all radial artery cannulations to show that there is an adequate palmar arch.