Background Administration of the wrong drug via the epidural or intrathecal route can cause devastating consequences. Because of the commonality of potassium replacement therapy coupled to its potential neurotoxic profile, we suspected that injuries related to this drug error would be present in the literature.

Objectives We aimed to identify clinical characteristics associated with the inadvertent administration of potassium chloride (KCl) during neuraxial anesthesia. Our secondary objective was to identify human factors that may have been associated.

Evidence review Published reports of neuraxial administration of KCl in humans were searched using Medline and Google Scholar. Error reports in any language were included.

Findings 25 case reports/series reported administration of KCl via epidural (25 patients) or intrathecal routes (three patients). There were six cases during interventional pain procedures, five cases in operating rooms and 17 in wards or intensive care units. Neuraxial KCl caused paraplegia in 22 patients. Mechanical ventilation was instituted in 11 of 28 patients. Three patients died. Epidural (eight patients) and spinal (two patients) lavage were performed to minimize consequences. A correctly prepared KCl infusion was connected to the epidural catheter for nine patients on wards (32%; 95% upper confidence limit: 48%) due to epidural–intravenous line confusion. Among the other 19 errors, KCl was confused with normal saline for 13 patients or local anesthetic in three patients. A wide range of concentrations and doses of KCl were administered. Variable use of intravenous steroid (13 patients) and epidural saline (eight patients) was found among patients who received epidural KCl. Human factors identified included incorrect visual perception, inadequate monitoring of infusions and substandard practice related to neuraxial anesthesia or analgesia.

Conclusions KCl administration via epidural or intrathecal route has been reported to cause catastrophic consequences.