Certified Post Anesthesia Nurse (CPAN) Practice Exam 2026 - Free CPAN Practice Questions and Study Guide

The assessment of Horner's syndrome is integral in determining the success of a stellate ganglion block because this condition arises from disruption of sympathetic nerve pathways, which are specifically targeted by the block. When a stellate ganglion block is effective, it typically leads to symptoms characteristic of Horner's syndrome, including ptosis (drooping of the eyelid), miosis (constricted pupil), and anhidrosis (lack of sweating) on the affected side of the face. The presence of these symptoms indicates that the block has successfully interrupted sympathetic outflow.

In contrast, while diaphoresis, pallor, and vasoconstriction can reveal information about circulation and sweating in the area surrounding the block, they do not directly indicate whether the block itself was successful. Diaphoresis may occur due to various factors unrelated to the ganglion block’s efficacy, and variations in pallor and vasoconstriction can be influenced by other physiological responses in the body. Thus, the assessment of Horner's syndrome provides a clearer and more reliable indicator of a successful stellate ganglion block.