Eye Problem Following Foot Surgery -- Abducens Palsy as a Complication of Spinal Anesthesia

Abstract and Introduction

Background: Paralysis of abducens nerve is a very rare complication of lumbar puncture, which is a common procedure most often used for diagnostic and anesthetic purposes.
Case Report: A 38-year-old man underwent surgery for a left hallux valgus while he was under spinal anesthesia. On the first postoperative day, the patient experienced a severe headache that did not respond to standard nonsteroidal anti-inflammatory medication and hydration. During the second postoperative day, nausea and vomiting occurred. On the fourth postoperative day, nausea ceased completely but the patient complained of diplopia. Examination revealed bilateral strabismus with bilateral abducens nerve palsy. His diplopia resolved completely after 9 weeks and strabismus after 6 months.
Conclusion: Abducens palsy following spinal anesthesia is a rare and reversible complication. Spinal anesthesia is still a feasible procedure for both the orthopaedic surgeon and the patient. Other types of anesthesia or performing spinal anesthesia with smaller diameter or atraumatic spinal needles may help decrease the incidence of abducens palsy. Informing the patient about the reversibility of the complication is essential during the follow-up because the palsy may last for as long as 6 months. Special attention must be paid to patient positioning following the operation. Recumbency and lying flat should be accomplished as soon as possible to prevent cerebrospinal fluid leakage and resultant intracranial hypotension. This becomes much more important if the patient has postdural puncture headache.

Lumbar puncture (LP) is a common procedure most often used for diagnostic and anesthetic purposes. The most common side effect of lumbar puncture is post-lumbar puncture headache (PLPH), which is due to cerebrospinal fluid (CSF) hypotension resulting from persistent spinal fluid leakage from the puncture site.^[1,2,3] Frequency of PLPH is less than 1% to 2% in skilled hands.^[4]

Injuries of the fourth and sixth cranial nerves have been reported after LP usually combined with PLPH.^[1,4,5,6,7] There is no uniform definition of severe PLPH. But a widely accepted definition is: a constant headache appearing or worsening significantly upon assuming the upright position and resolving or improving significantly upon lying down.^[8]

The importance of this pattern of headache is that it usually develops before the onset of paralysis of the abducens nerve,^[1,4,5,6,7] which is the most commonly affected nerve.^[1,6] Besides the diagnostic LP, epidural and spinal anesthesia, myelography, and ventricular shunting for hydrocephalus may also lead to abducens nerve palsies.^{[1,4,5,6,7,9]}

Risk of abducens palsy after LP is not definite. A study by Thomke and colleagues report it to be 1 in 5800,^[3] and Follens and colleagues^[6] report that the incidence is 1 in 400. The incidence of abducens palsy after myelography is 1 in 500 cases.^[4] Abducens palsy after LP can be unilateral or bilateral.^[1,6] It usually occurs 4-14 days after LP and resolves completely after 4 weeks to 4 months.^{[1,3,4,5,6,7,9]} We report a case of abducens nerve palsy following spinal anesthesia.

© 2005 Medscape

Cite this: Eye Problem Following Foot Surgery -- Abducens Palsy as a Complication of Spinal Anesthesia - Medscape - Oct 13, 2005.