Transient Horner's syndrome following thoracic epidural anesthesia for mastectomy: a prospective observational study

Transient Horner's syndrome is an uncommon complication of epidural anesthesia, though its exact incidence in thoracic epidural anesthesia is not clear. Therefore, this study prospectively evaluated the incidence of Horner's syndrome after thoracic epidural anesthesia for mastectomy.

Patients scheduled for mastectomy, with or without breast reconstruction, were enrolled in this prospective observational study from September 2010 to December 2013. Intraoperative thoracic epidural anesthesia was established using 0.375% or 0.5% ropivacaine 15 mL with thoracic epidural analgesia continued postoperatively with a continuous infusion of 0.15% ropivacaine 2 mL·hr(-1) with fentanyl 8 μg·hr(-1). Signs of Horner's syndrome (miosis, ptosis, and hyperemia) were assessed at one and two hours as well as one, two, and three days postoperatively.

Thoracic epidural anesthesia was successful in 439 patients, with six (1.4%) of these patients acquiring Horner's syndrome. All signs of Horner's syndrome resolved gradually within 180 min of discontinuing the epidural infusion. In one patient with Horner's syndrome, a radiographic contrast injection confirmed that the drug had spread to the cervical epidural level.

The incidence of Horner's syndrome following thoracic epidural anesthesia and continuous thoracic epidural analgesia for mastectomy was 1.4%. The mechanism was consistent with cephalic spread of the epidural local anesthetic. This trial was registered at: Clinicaltrials.gov, number: NCT02130739.