Central nervous system toxicity of sodium nitroprusside in treatment of patients with aortic dissection

This study examined the sodium nitroprusside (SNP) toxicity to central nervous system (CNS) in treatment of patients with aortic dissection (AD). The medical records of 191 AD patients who were admitted to Tongji Hospital, China, from Jan. 1998 to Feb. 2009 were retrospectively analyzed. There were 140 cases of hypertension (73.3%) and 13 cases of Marfan syndrome (6.8%) among the 191 AD patients. A total of 157 patients were given SNP treatment. The toxic reactions of CNS occurred in 18 subjects (11.5%). Most of the adverse reactions occurred on the fifth day following SNP injection. SNP infusion rate was significantly higher in patients who developed CNS toxicity. It was suggested that systemic hypertension is the most common predisposing factor for AD. The combination of SNP with a beta-receptor blocker is a medical therapy commonly used in patients with AD. Cyanide and thiocyanate toxicity from SNP treatment is always the consequence of prolonged drug infusion or relatively high dose administration.