Pneumonia preceding respiratory failure. A rare, easily misleading clinical manifestation in adult Arnold-Chiari malformation

Delayed post-operative aggravation of sleep related disturbances in patients of basilar invagination with Chiari malformation: case report and review of the literature

Sleep apnoea is common in patients with Basilar Invagination with Arnorld Chiari Malformation (ACM). Various studies have shown its incidence in the range of 60-70% among such patients. Most of the studies have shown improvement in sleep disturbances after decompressive surgeries for Chiari Malformations. There is no report of postoperative deterioration due to sleep apnoea in these patients. Authors report two cases of basilar invagination associated with ACM and Platybasia, who deteriorated probably due to worsening of pre-existing sleep disorders on 3rd and 7th postoperative days after their surgeries, despite clinico-radiological improvements during their early post-operative courses. Authors discuss literature related to sleep apnoea in basilar invagination associated with Chiari Malformations and share precautions, which are relevant and should be undertaken in such patients especially during early post-operative periods to avoid alarming complication which may occur even in experienced hands.

A Conditional Inference Tree Model for Predicting Sleep-Related Breathing Disorders in Patients With Chiari Malformation Type 1: Description and External Validation

STUDY OBJECTIVES

The aim of this study is to generate and validate supervised machine learning algorithms to detect patients with Chiari malformation (CM) 1 or 1.5 at high risk of the development of sleep-related breathing disorders (SRBD) using clinical and neuroradiological parameters.

METHODS

We prospectively included two independent datasets. A training dataset (n = 90) was used to obtain the best model, whereas a second dataset was used to validate it (n = 74). In both cohorts, the same clinical, neuroradiological, and sleep studies were carried out. We used two supervised machine learning approaches, multiple logistic regression (MLR) and the unbiased recursive partitioning technique conditional inference tree (URP-CTREE), to detect patients at high risk of SRBD. We then compared the accuracy, sensitivity, and specificity of the two prediction models.

RESULTS

Age (odds ratio [OR] 1.1 95% confidence interval [CI] 1.05-1.17), sex (OR 0.19 95% CI 0.05-0.67), CM type (OR 4.36 95% CI 1.14-18.5), and clivus length (OR 1.14 95% CI 1.01-1.31) were the significant predictor variables for a respiratory disturbance index (RDI) cutoff that was ≥ 10 events/h using MLR. The URP-CTREE model predicted that patients with CM-1 who were age 52 years or older and males with CM-1 who were older than 29 years had a high risk of SRBD. The accuracy of predicting patients with an RDI ≥ 10 events/h was similar in the two cohorts but in the URP-CTREE model, specificity was significantly greater when compared to MLR in both study groups.

CONCLUSIONS

Both MLR and URP-CTREE predictive models are useful for the diagnosis of SRBD in patients with CM. However, URP-CTREE is easier to apply and interpret in clinical practice.

Chiari Syndrome and Respiratory Failure

Background:

Patients with failed extubation requiring reintubation have increased morbidity and mortality. This situation may reflect the severity of the underlying disorder or may reflect an undiagnosed condition that was not apparent at the time of the initial intubation.

Methods:

Case report and literature review.

Results:

A 49-year-old man developed acute hypercapneic respiratory failure during an episode of community-acquired pneumonia. This patient failed extubation 4 times. Routine neurological evaluation, including computed tomography of the head, was within normal limits. A magnetic resonance imaging revealed a severe Chiari malformation type I. The patient eventually required tracheostomy and prolonged mechanical ventilation. We identified 28 cases with Chiari malformations (CM) in the medical literature, who presented with respiratory failure. The mean age was 29.5 years, 46% of the cases were male, 50% had an associated syringomyelia, and 64% required a decompressive surgery. Twenty-five percent had recurrent symptoms postsurgery.

Conclusions:

Patients with CMs can have repeated extubation failures. Some of these patients have normal neurological examinations and studies and are not identified until they have an MRI study. Clinicians need to consider this possibility in patients who are difficult to wean.

Type I Arnold-Chiari malformation with bronchiectasis, respiratory failure, and sleep disordered breathing: a case report

Arnold Chiari Malformation (ACM) is defined as a condition where part of the cerebellar tissue herniates into the cervical canal toward the medulla and spinal cord resulting in a number of clinical manifestations. Type I ACM consists of variable displacement of the medulla throughout the formamen magnum into the cervical canal, with prominent cerebellar herniation.

Type I ACM is characterized by symptoms related to the compression of craniovertebral junction, including ataxia, dysphagia, nistagmus, headache, dizziness, and sleep disordered breathing. We report a case of a life-long non-smoker, 54 years old woman who presented these symptoms associated with bronchiectasis secondary to recurrent inhalation pneumonia, hypercapnic respiratory failure, and central sleep apnea (CSA).

CSA was first unsuccessfully treated with nocturnal c-PAP. The subsequent treatment with low flow oxygen led to breathing pattern stabilization with resolution of CSA and related clinical symptoms during sleep. We suggest that in patients with type I ACM the presence of pulmonary manifestations aggravating other respiratory disturbances including sleep disordered breathing (SDB) should be actively investigated. The early diagnosis is desirable in order to avoid serious and/or poorly reversible damages.

Chiari malformation Type I in children younger than age 6 years: presentation and surgical outcome

OBJECT

The authors conducted a study to evaluate the unique presenting signs and symptoms of Chiari malformation Type I (CM-I) in children younger than 6 years of age and highlight the benefits of early surgical treatment in this patient population.

METHODS

The authors reviewed the medical records of patients who presented to the neurosurgery department before their 6th birthday and subsequently underwent surgery for CM-I. They identified 39 patients who had been evaluated between 1984 and 2007 and examined the medical records for presentation, surgical intervention, and outcome.

RESULTS

Children aged 0-2 years commonly presented with oropharyngeal dysfunction (77.8%). Children aged 3-5 years more frequently presented with syringomyelia (85.7%), scoliosis (38.1%), and/or headache (57.1%). All patients underwent posterior fossa craniectomy. Additionally, in many patients cervical laminectomy and/or duraplasty was performed. A few patients required transoral decompression and occipitocervical fusion. In most cases, surgery led to resolution or dramatic improvement of initial symptoms.

CONCLUSIONS

Early recognition and surgical treatment of CM-I in young children leads to good outcomes in the majority of patients. Additional therapies for oropharyngeal dysfunction, syringomyelia, and scoliosis can frequently be avoided.

Adult Chiari malformation and sleep apnoea

Chiari malformation (CM) is primarily characterised by herniation of the cerebellar tonsils through the foramen magnum. Clinically, two main types of CM represent the vast majority of cases: type I (in adults) and type II (in infants). CM may result in neuronal impairment of the brainstem, upper spinal cord and cranial nerves. Part of the afferent and efferet systems and the central respiratory controlling system are located in the cranium-cervical transition and may be damaged in these pathologies, leading to respiratory disorders, such as respiratory failure and death. The ventilatory responses to exogenous and endogenous stimuli, such as responses to hypoxia and hypercapnia, are usually diminished, and apnea may be manifested and detected during sleep, allowing for the diagnosis. This study is a review of the relationship between sleep apnoea and adult CM.

Evaluation and management of the Chiari malformation type 1 for the primary care pediatrician

Diagnosis and treatment of CMI is undergoing reexamination that includes redefinition of the anatomic Chiari malformation and refinement and redefinition of the clinical syndrome. Children with SMI present with head pain of some kind, a neurologic deficit, or with signs of spinal cord dysfunction from syrinx. Some will present with no clinical syndrome at all. Presence of anatomic Chiari malformation or compelling clinical Chiari syndrome should lead to evaluation by a neurologist or neurosurgeon experienced with the syndromes and their treatment. Treatment options are varied but usually result in resolution of symptoms. When symptoms persist after surgery, management is complex and not uniformly successful, even in the most experienced hands.

A prospective controlled study of sleep respiratory events in patients with craniovertebral junction malformation

Object. Craniovertebral junction malformation (CVJM) or Chiari malformation in adults, with or without syringomyelia and basilar invagination, produces neuronal dysfunction of the brainstem, cerebellum, cranial nerves, and upper spinal cord. The respiratory center and some of its afferent and efferent components can be altered in these diseases. The authors studied patients with and without CVJM to determine whether this physical feature contributed to sleep disturbances.

Methods. Respiratory manifestations during sleep were studied prospectively, by using whole-night polysomnography, in 32 symptomatic patients (CVJM group) and 16 healthy volunteers (control group). Patients with CVJM presented with more sleep disturbances (reports of snoring and apnea) than those in the control group. The apnea/hypopnea index values were higher in patients with CVJMs than in the control group (13 ± 15 compared with 3 ± 6; p = 0.007) and the rate of central sleep apneas was higher in the CVJM than in the control group (22 ± 30 compared with 4 ± 8%; p = 0.009). The apnea/hypopnea index was highest in the subgroup with basilar invagination than in the other subgroups. The central apneic episodes were more frequent in the patients with basilar invagination (35 ± 40%; p = 0.001) and in those with syringomyelia (17.6 ± 24.6%; p = 0.003) than in the control group (4 ± 8%). Patients with symptomatic CVJM, especially those with basilar invagination, presented with more sleep respiratory compromise than did those in the control group.

Conclusions. The incidence of sleep apnea/hypopnea syndrome is significantly higher in patients with CVJM.

Corticospinal pathway and exercise hyperpnea: lessons from a patient with Arnold Chiari malformation

The study of a patient with an Arnold Chiari malformation gave us the opportunity to test the hypothesis that the motor cortex contributes significantly to respiratory control during muscular exercise through the corticospinal pathway. The patient was a 25 years old woman who exhibited a severe impairment of the 'automatic' ventilatory control due to a type I Arnold Chiari malformation. Since she never complained of being breathlessness even on exertion, the breath-by-breath ventilatory (VE) and pulmonary gas exchange responses to a three minute bout of constant work rate exercise at 60 W, 90 W and 120 W were studied before then 16 and 23 months after posterior fossa decompression. The VE response to the three different levels of exercise was dramatically blunted so that the expected vertical relationship between PET(CO(2)) and VE during moderate exercise was replaced by an almost horizontal relationship with a slope ranging from 0.15 to 0.17 l/min/Torr. The reduced VE response was associated with a total lack of respiratory sensation during and following the exercise bouts. This abnormal ventilatory response to exercise persisted despite posterior fossa decompression. There was however no evidence of an alteration of the corticospinal pathway. Indeed, not only was there no sign of motor deficit but the patient was able both to mobilize 96% of her expected vital capacity and to voluntarily increase her ventilation to the level expected in a normal subject during exercise. This observation suggests that during exercise, motor control of respiratory muscles via a direct corticospinal pathway does not play a major role in adjusting phrenic motoneuron activity to the magnitude of the motor inputs to the exercising skeletal muscles.