Preoperative autonomic dysfunction does not improve significantly after surgical management. 术前交感神经功能失调并不会在手术后有明显的进展。
Syncope is a brief loss of consciousness with collapse resulting from transient brain dysfunction based on decreased blood flow or neurologic insult. 晕厥是暂时性意识丧失并跌倒，它是因为血流减少或神经损伤而造成一过性大脑功能失调而引起的。
