Cranial nerve VI palsy after dural-arachnoid puncture

Unveiling the vulnerability of the human abducens nerve: insights from comparative cranial base anatomy in mammals and primates

The topographic anatomy of the abducens nerve has been the subject of research for more than 150 years. Although its vulnerability was initially attributed to its length, this hypothesis has largely lost prominence. Instead, attention has shifted toward its intricate anatomical relations along the cranial base. Contrary to the extensive anatomical and neurosurgical literature on abducens nerve anatomy in humans, its complex anatomy in other species has received less emphasis. The main question addressed here is why the human abducens nerve is predisposed to injury. Specifically, we aim to perform a comparative analysis of the basicranial pathway of the abducens nerve in mammals and primates. Our hypothesis links its vulnerability to cranial base flexion, particularly around the sphenooccipital synchondrosis. We examined the abducens nerve pathway in various mammals, including primates, humans (N = 40; 60% males; 40% females), and human fetuses (N = 5; 60% males; 40% females). The findings are presented at both the macroscopic and histological levels. To associate our findings with basicranial flexion, we measured the cranial base angles in the species included in this study and compared them to data in the available literature. Our findings show that the primitive state of the abducens nerve pathway follows a nearly flat (unflexed) cranial base from the pontomedullary sulcus to the superior orbital fissure. Only the gulfar segment, where the nerve passes through Dorello's canal, demonstrates some degree of variation. We present evidence indicating that the derived state of the abducens pathway, which is most pronounced in humans from an early stage of development, is characterized by following the significantly more flexed basicranium. Overall, the present study elucidates the evolutionary basis for the vulnerability of the abducens nerve, especially within its gulfar and cavernous segments, which are situated at the main synchondroses between the anterior, middle, and posterior cranial fossae-a unique anatomical relation exclusive to the abducens nerve. The principal differences between the pathways of this nerve and those of other cranial nerves are discussed. The findings suggest that the highly flexed human cranial base plays a pivotal role in the intricate anatomical relations and resulting vulnerability of the abducens nerve.

Cranial Nerve Six Palsy After Vaginal Delivery with Epidural Anesthesia: A Case Report

BACKGROUND

This case report describes a 34-year-old woman who developed diplopia and strabismus 2 weeks after a vaginal delivery and epidural anesthesia.

CASE REPORT

A 34-year-old women presented to the emergency department (ED) with continued headache and new-onset diplopia after having undergone epidural anesthesia for a vaginal delivery 2 weeks prior. During that time, she underwent two blood patches, rested supine, drank additional fluids, and consumed caffeinated products for her spinal headache. When she developed double vision from a cranial nerve VI palsy, she returned to the ED. At that time, she had a third blood patch performed, and she was evaluated by a neurologist. The medical team felt the cranial nerve VI palsy was due to the downward pull of the brain and stretching of the nerve. Magnetic resonance imaging and neurosurgical closure of the dura were considered as the next steps in treatment; however, they were not performed after being declined by the patient. All symptoms were resolved over the next 3 weeks. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case illustrates the uncommon complication of a cranial nerve VI palsy from a persistent cerebrospinal fluid leak after a dural puncture. Emergency physicians must be aware that diplopia can be a rare presenting symptom after patients undergo a lumbar puncture. Furthermore, emergency physicians should be aware of the multiple treatment options available. Knowledge of the timeline of resolution of the diplopia is necessary to make shared decisions with our patients about escalating care.

Vocal Fold Paralysis After Spinal and Epidural Anesthesia: A Case Report and Scoping Review

OBJECTIVES

Cranial nerve paralysis is a rare complication of spinal and epidural anesthesia, and some cases of vocal fold paralysis (VFP) have been reported. The aim of this article is to report a case, identify evidence supporting the possibility of VFP being a complication of spinal and epidural anesthesia and to investigate the frequency, the characteristics, and the possible mechanisms of such a complication.

DATA SOURCES

CINAHL Complete, Google Scholar, Cochrane Library, Pubmed, and EMBASE.

METHODS

Case report according to CARE guidelines; scoping review according to PRISMA-ScR criteria. All types of studies that reported on patients of any age and sex, all types of spinal/epidural anesthesia regardless of the location and of drugs used were included. A data extraction sheet was completed for each study selected for inclusion based on the full-text screenings. Extracted data included: study characteristics, participant characteristics, intervention characteristics, outcome measures, clinical investigations. The study did not receive external funding.

RESULTS

Eight studies met inclusion criteria and a total of 13 events (in 12 patients, including ours) were reported to date. Although there are some hypotheses in regard to the mechanism underlying the phenomena, including mechanical and inflammatory ones, the exact cause is still unclear.

CONCLUSIONS

Only few cases of VFP after spinal or epidural anesthesia have been reported to date; however, it seems possible that VFP might be a potential underreported complication of such procedures. We believe that more research on the topic is warranted, especially considering the wide population potentially at risk.

LEVEL OF EVIDENCE

NA Laryngoscope, 2024.

Long-term complications of unintentional dural puncture during labor epidural analgesia: a case-control study

INTRODUCTION

Epidural analgesia is the preferred method to manage pain during labor and delivery. The insertion of the epidural catheter can be complicated by unintentional dural puncture that may result in postdural puncture headache. There is limited evidence on the long-term implications of this complication. We sought to investigate if women who sustained a dural puncture have a higher risk of developing chronic headache, low back pain and visual or auditory impairment.

METHODS

We conducted a 1:1 case-control study with women who delivered at our institution from January 2015 to December 2019. Cases were women who received epidural analgesia and sustained an unintentional dural puncture, and controls were women who received epidural analgesia but did not sustain such complication. We matched cases and controls for date of delivery, age, and body mass index. All women completed an online survey with validated questionnaires for diagnosis of chronic headache and chronic back pain. We used dichotomic (yes/no) questions to look for the presence of chronic visual and auditory impairment.

RESULTS

Sixty-three case-control pairs were studied. Women who sustained a dural puncture during their epidural catheter insertion had a higher risk of developing chronic headache (14.3%, vs 4.8%, p=0.057, adjusted OR (AOR): 3.67 (95% CI 1.05 to 12.82)) and chronic back pain (39.7% vs 19.1%, p=0.009, AOR: 2.67 (95% CI 1.25 to 5.72)) than women who did not sustain a dural puncture. The incidence of chronic auditory impairment was also higher in the dural puncture group (14.3% vs 1.6%, p=0.01, AOR: 9.98 (95% CI 1.21 to 82.62)).

CONCLUSIONS

An unintentional dural puncture during epidural catheter insertion in parturients is associated with increased risk of chronic headache, back pain and auditory impairment.

Postdural Puncture Headache-Risks and Current Treatment

PURPOSE OF REVIEW

This manuscript aims to review the risks and the current treatments for postdural puncture headache (PDPH).

RECENT FINDINGS

PDPH is a relatively frequent complication after neuraxial blocks. It is typically orthostatic in nature, presenting as a positional and dull aching or throbbing headache, with added dysregulation of auditory and/or visual signals. Certain characteristics, such as female sex and young age, may predispose patients to the development of PDPH, as may factors such as previous PDPH, bearing down during the second stage of labor, and the neuraxial technique itself. Long-term complications including chronic headache for years following dural puncture have brought into question of the historical classification of PDPH as a self-limiting headache. So far, the underlying mechanism governing PDPH remains under investigation, while a wide variety of prophylactic and therapeutic measures have been explored with various degree of success. In case of mild PDPH, conservative management involving bed rest and pharmacological management should be used as first-line treatment. Nerve blocks are highly efficient alternatives for PDPH patients who do not respond well to conservative treatment. In case of moderate-to-severe PDPH, epidural blood patch remains the therapy of choice. An interdisciplinary approach to care for patients with PDPH is recommended to achieve optimal outcomes.

Delayed Cranial Nerve Palsies and Chiari Type I Malformation After Epidural Anesthesia in the Setting of Childbirth

Epidural analgesia is an efficient method of controlling pain and has a wide spectrum of therapeutic and diagnostic applications. Potential complications may occur in a delayed fashion, can remain undiagnosed, and can be a source of significant morbidity. We present a 37-year-old woman presented with severe spontaneous occipital headaches, diplopia, and dizziness that occurred spontaneously six weeks after giving birth. Her primary method of pain control during labor was epidural analgesia. Her neurologic exam revealed a cranial nerve six palsy with ptosis, and her brain MRI demonstrated a Chiari I malformation which had not been previously diagnosed. CT myelography of the lumbar spine revealed extradural contrast extravasation within the interspinous soft tissue at L1-L2, which was the site of her prior epidural procedure. She underwent epidural blood patch administration, and her cranial nerve palsy resolved along with all of her other symptoms. The development of concurrent Chiari I malformation and cranial nerve palsy after epidural anesthesia is an exceptionally rare occurrence. Neurologic complications after epidural anesthesia are likely under-reported, since patients are often lost to follow-up or have subtle neurologic signs which can easily be missed. This frequently delayed presentation emphasizes the importance of patient education and the necessity of a detailed neurological exam when symptoms occur.

Vocal fold paralysis and cauda equina syndrome following spinal-epidural anesthesia: A case report

RATIONALE

Vocal fold paralysis and cauda equina syndrome are very rare neurologic deficits. This report describes the case of a patient who simultaneously developed both after uneventful spinal-epidural anesthesia with 0.5% hyperbaric bupivacaine.

PATIENT CONCERNS

We report the case of a 45-year-old female, who underwent surgery for bilateral hallux valgus developed cauda equina syndrome and unilateral vocal fold paralysis after uneventful spinal-epidural anesthesia was administered. There was no pain or paresthesia during needle placement or drug injection. Surgery was performed uneventfully.

DIAGNOSES

Right vocal fold paralysis was diagnosed with flexible laryngoscopy.

INTERVENTIONS

Patient was started on the treatment with a surgery for bilateral hallux valgus, who developed cauda equina syndrome and unilateral vocal fold paralysis after uneventful spinal-epidural anesthesia was administered.

OUTCOMES

Postoperatively, she had difficulty in urination and defecation. In addition, she developed unilateral vocal fold paralysis characterized by hoarseness, effortful voice production, and choking with liquids. Magnetic resonance imaging performed on the lumbosacral area and computed tomography of the neck, the chest, and the skull revealed entirely normal results. However, flexible laryngoscopy revealed a right vocal fold paralysis. Although cauda equina syndrome can occur due to neurotoxicity of local anesthetics, the exact etiology of vocal fold paralysis is uncertain.

LESSONS

The case highlights that 2 rare and serious complications of spinal-epidural anesthesia can even occur in the same patient after uneventful surgery and block performance.

Ultrasound-Guided Unilateral Transversus Abdominis Plane Combined with Rectus Sheath Block versus Subarachnoid Anesthesia in Patients Undergoing Peritoneal Dialysis Catheter Surgery: A Randomized Prospective Controlled Trial

Background

Peritoneal dialysis catheter placement can be performed under general anesthesia, local anesthesia or subarachnoid anesthesia (SA). Recently, studies have reported the successful placement of peritoneal dialysis catheters using a transversus abdominis plane (TAP) block and rectus sheath (RS) block. This study compared the TAP + RS block with SA for patients undergoing peritoneal dialysis catheter placement.

Methods

Sixty patients were randomly divided into two groups, with 30 receiving unilateral ultrasound-guided TAP + RS block anesthesia and 30 receiving SA. The demographic characteristics, anesthesia efficacy, indicators related to anesthesia or operation, hemodynamic index, postoperative pain numeric rating score (NRS), postoperative recovery indicators, complications related to anesthesia or surgery, and dosage of sedative or analgesic medication were analyzed.

Results

Anesthesia operation time was significantly shorter in the TAP + RS block group than in the SA group (P<0.001), while there was no significant difference in success rates (TAP + RS 93.33% [95% confidence interval, 95% CI, 83.9–102.8%] vs SA 100.00% [95% CI, 100–100%], P=0.472). Two patients in the TAP + RS group needed extra analgesia, although the dermatome pinprick sensation test gave negative results for all patients. Patients who received the TAP + RS block expressed significantly less pain on movement or at rest at 4 h and 8 h postoperative. Fewer patients needed rescue analgesia with tramadol in the postoperative period in the TAP + RS block group than in the SA group (P<0.05). The intraoperative MAP was more stable (P<0.05) in the TAP + RS group compared to the SA group.

Conclusion

The TAP + RS block is a safe, effective method for use as the principal anesthesia technique in PD catheter placement. Compared to SA, it has the advantages of less influence on hemodynamics and a better postoperative analgesic effect.

A UNIQUE CASE OF BILATERAL VOCAL FOLD PARALYSIS FOLLOWING SPINAL ANAESTHESIA

Cranial nerve palsies are potential but rare complications of spinal anaesthesia. Most of the literatures support upper cranial nerve palsies like VI, IV and III cranial nerve palsies. Intrathecal hypotension resulting in tractional injury of the cranial nerves is the likely mechanism of injury. As on date, some cases of unilateral vocal fold paralysis and very little bilateral vocal fold paralysis have been described in case reports. We have described a patient who developed hoarseness and dysphagia 7 days after receiving spinal anaesthesia for fixation of inter-trochanteric fracture femur. The patient was diagnosed with bilateral vocal fold paralysis. He was managed conservatively and exhibited complete spontaneous recovery as has been described in the previously reported cases. Any patient presenting with idiopathic vocal fold paralysis should be enquired about the history of spinal or epidural anaesthesia. If the history is affirmative, then it points towards transient intrathecal hypotension as a potential etiology of the cranial nerve palsy.

Treatment of obstetric post-dural puncture headache. Part 2: epidural blood patch

The 2009-12 MBRRACE-UK report highlighted the deaths of two women in whom dural puncture had occurred during insertion of a labour epidural catheter. Despite suffering long-term headaches, neither woman was adequately followed-up after discharge from hospital. Death resulted from a cerebral vein thrombosis in one case and a subdural haematoma in the other. Due to significant variation in the treatment of obstetric post-dural puncture headache, an Obstetric Anaesthetists' Association working group was set up to produce evidence-based guidelines to guide clinicians. These guidelines have been condensed into two review articles. In this second review, the role of an epidural blood patch is discussed using a question and answer format.

Bilateral Vocal Fold Paralysis After Epidural Anesthesia

Cranial neuropathies are known potential complications of spinal anesthesia, with most reports describing upper cranial nerve involvement. Intrathecal hypotension resulting in traction injury of the cranial nerves is the likely mechanism of injury. Unilateral vagal neuropathy was first described recently. The patient discussed in this case presented with hoarseness and dysphagia after receiving epidural anesthesia for childbirth. Following videostroboscopy and laryngeal electromyogram, she was diagnosed with bilateral vocal fold paralysis. The patient was managed conservatively with expectant management. She exhibited complete spontaneous recovery, as has been the natural history previously described for similar injuries. The proposed mechanism for this patient, and in others described in the literature, is puncture of the dura with subsequent egress of cerebrospinal fluid, leading to intracranial hypotension and traction on cranial nerves. Unilateral vocal fold paralysis following spinal anesthesia has been reported in one case series consisting of three patients, but this represents the first case of bilateral paralysis. Spontaneous resolution has been observed in all patients. Patients presenting with idiopathic vocal fold paralysis, in summary, should be questioned about recent history of epidural or spinal anesthesia, as a positive history may point to transient intrathecal hypotension as a potential etiology of the paralysis. 

Vocal fold paralysis due to intracranial hypotension following spinal anesthesia

Cranial nerve palsy is a rare neurological complication of epidural and subarachnoid blocks. Most of these complications are attributed to secondary intracranial hypotension due to cerebrospinal fluid leakage following dural puncture. Vocal fold paralysis (VFP) seems more likely to be overlooked and underreported due to delayed onset of symptoms and lack of attribution of dysphonia to spinal anesthesia. Therefore, VFP can often be missed and described as idiopathic. This article describes a case of VFP due to vagus nerve injury following subarachnoid block.

Postdural Puncture Headache: An Evidence-Based Approach

Headache after dural puncture is a common complication accompanying neuraxial anesthesia. The proposed cause is loss of cerebrospinal fluid through the puncture into the epidural space. Although obstetric patients are at risk for the development of this headache because of female gender and young age, there is a difference in the obstetric population. Women who deliver by cesarean delivery have a lower incidence of headache after dural puncture compared with those who deliver vaginally. Treatment of postdural puncture headache is an epidural blood patch. Departments should develop protocols for management of accidental dural puncture, including appropriate follow-up and indications for further management.