Arnold‐Chiari malformation type 1 as an unusual cause of acute respiratory failure: A case report

Acute Respiratory Failure Requiring Invasive Ventilation in Adults With Congenital Syringomyelia/Arnold-Chiari Malformations: A Systematic Review

Arnold-Chiari malformations (ACM) and congenital syringomyelia/syrinx are rare neurological phenomenons that can present as acute respiratory failure and contribute to multiple extubation failures despite surgical intervention. A systematic review was conducted to scrutinize the current literature, screening 65 papers and including 12 papers (13 patients). Sixty-one percent of patients had type 1 ACM and 70% had a congenital syringomyelia. Neurosurgical intervention occurred in seven patients, five patients had at least one extubation failure which was due to apnea or reoccurrence of respiratory failure, and eight patients needed tracheostomies. The neurosurgical intervention aims to improve patient symptoms, but our data and current literature suggest that patients with these pathologies still undergo long ventilation weans and are not liberated from the ventilator due to ongoing respiratory failure.

Coronavirus disease 2019-associated persistent cough and Chiari malformation type I resulting in acute respiratory failure: illustrative case

BACKGROUND

Chiari malformation type I (CM-I) is the herniation of cerebellar tonsils through the foramen magnum, potentially resulting in the obstruction of cerebrospinal fluid flow and brainstem compression. Sleep-disordered breathing (SDB) is common in patients with CM-I, and symptomatic exacerbations have been described after Valsalva-inducing stressors. Acute decompensation in the setting of coronavirus disease 2019 (COVID-19) has not been described.

OBSERVATIONS

After violent coughing episodes associated with COVID-19 infection, a 44-year-old female developed several months of Valsalva-induced occipital headaches, episodic bulbar symptoms, and worsening SDB, which led to acute respiratory failure requiring mechanical ventilation. Imaging demonstrated 12 mm of cerebellar tonsillar descent below the foramen magnum, dorsal brainstem compression, and syringobulbia within the dorsal medulla. She underwent posterior fossa and intradural decompression with near-complete resolution of her symptoms 6 months postoperatively.

LESSONS

Although CM-I can remain asymptomatic, Valsalva-inducing stressors, including COVID-19 infection, can initiate or acutely exacerbate symptoms, placing patients at risk for CM-I-associated brainstem dysfunction and, in rare cases, acute respiratory failure. Worsening Valsalva maneuvers can contribute to further cerebellar tonsil impaction, brainstem compression, syringomyelia/syringobulbia, and worsening CM-I intradural pathology. Ventilator support and timely decompressive surgery are paramount, as brainstem compression can reduce central respiratory drive, placing patients at risk for coma, neurological deficits, and/or death.

Use of Intraoperative Neuromonitoring in Surgical Treatment of Acute Presentation of Chiari I Malformation: A Case Report

Intraoperative neuromonitoring (IONM) has been used in neurosurgical procedures to assess patient safety and minimize risk of neurological deficit. However, its use in decompressive surgeries of Chiari malformation type I (CM-I) remains a topic of debate. Here we present the case of a 5-year-old girl who presented with acute right lower extremity monoplegia after accidental self-induced hyperflexion of the neck while playing. Imaging revealed 15 mm of tonsillar ectopia with cervical and upper thoracic spinal cord edema. She was taken to surgery for a suboccipital decompression with expansile duraplasty. IONM demonstrated improvement in motor evoked potentials during the decompression. Postoperatively, she had full recovery of strength and mobility. This is a case of acute weakness after mild trauma in the setting of previously asymptomatic CM-I that showed close correlation with IONM, clinical findings, and imaging. IONM during decompressive surgery for CM-I may be useful in patients who present acutely with cervical cord edema.