Inadvertent Intrathecal Drug Injection Treating Low Back Pain

Abstract and Introduction

Abstract

Background: Undesired intrathecal injections represent an important subset of medical errors, albeit rare. Clinical effects depend on the type and concentration of drug(s) injected. Here we report on the case of a healthy woman with persistent low back pain, treated with a paravertebral injection of lidocaine, thiocolchicoside, and L-acetylcarnitine at an orthopedic practice.

Case Report: A 42-year-old Caucasian woman, with no relevant past medical history, received a lumbar paravertebral injection of lidocaine, thiocolchicoside, and L-acetylcarnitine for persistent low back pain. Approximately 30 minutes after injection, she experienced quick neurological worsening. Upon arrival at the Emergency Department, she was comatose, with fixed bilateral mydriasis, trismus, and mixed acidosis; seizures ensued in the first hours; slow progressive amelioration was observed by day 6; retrograde amnesia was the only clinical relevant remaining symptom by 6 months.

Conclusions: To our knowledge, this is the first reported case of inadvertent intrathecal thiocolchicoside injection in an adult patient, as well as the first in the neurosurgical literature. Our experience suggests that injection therapy for low back pain should be administered in adequate settings, where possible complications may be promptly treated.

Introduction

Introduction and Background

The intrathecal space became an important venue for medical interventions in recent years, both in anesthesia and in many other medical specialties.^[1,2] Drugs to be intrathecally administered have to be accurately selected, to ensure that the drugs themselves, their preservatives or adjuncts may not be irritant or harmful to nervous tissues.^[1,2] As a consequence, any medication that may cause neurotoxicity is strictly prohibited from intrathecal use.^[1,2]

Undesired intrathecal injections (UII) represent an important subset of medical errors, albeit rare. Clinical effects of UII depend on the type and concentration of drug(s) inadvertently injected, and may range from no adverse reaction to profound morbidity, up to possibly related mortality.^[2]

Here we report on the case of a healthy woman with persistent low back pain, treated with paravertebral injections of lidocaine, thiocolchicoside, and L-acetylcarnitine in a medical practice, developing rapid neurologic deterioration requiring intensive care admission, with a final diagnosis of chemical meningo-encephalitis.