Transient thermal sympathectomy as a possible mechanism for hypotension after kyphoplasty: a case report.

Soto, Eliezer; Galperin, Mark; Portenoy, Russell K

BACKGROUND Vertebroplasty and kyphoplasty are minimally invasive treatments for vertebral compression fractures. Although infrequent, both transitory and persistent adverse effects have been reported. They range from asymptomatic to severe neurological deficits that are caused directly by polymethylmethacrylate (PMMA) leakage or may be related to local or general reactions not due to PMMA leakage. Transitory hypotension after the procedure has been observed, but the characteristics and etiology of this phenomenon are not defined. OBJECTIVE To describe a case of prolonged hypotension after kyphoplasty and suggest a possible mechanism. METHODS Six months after L2 kyphoplasty, a 63-year-old woman with severe osteoporosis developed a new back pain due to compression fracture of L1 and compression deformity of the superior L3 endplate. The patient underwent bilateral kyphoplasty at the L1 and L3 levels. She developed persistent hypotension for approximately 46 hours immediately after the procedure. Common causes of hypotension were ruled out and the event resolved spontaneously. RESULTS On the basis of needle placement, the temporal relationship between the procedure and blood pressure change, and the lack of other identifiable causes, thermal sympathectomy from heating of the PMMA adjacent to the paravertebral sympathetic chain is proposed as a potential mechanism. LIMITATIONS Single case report based on clinical observation. DISCUSSION Prolonged hypotension can complicate kyphoplasty at upper lumbar levels. Two days of severe hypotension has not been described as a complication of kyphoplasty. Although the mechanism is unknown, a transient thermal sympathectomy may be the cause.