Central neurogenic hyperventilation: A sign of CNS lymphoma

Diffuse large B-cell lymphoma with contemporary involvement of central and peripheral nervous system: A case report and literature review

Introduction

Simultaneous involvement of the peripheral nervous system (PNS) and central nervous system (CNS) during the same period in diffuse large B-cell lymphoma (DLBCL) is rarely documented. In this particular case, the diagnosis of diffuse large B-cell lymphoma was pathologically confirmed, with invasion into the basal ganglia, diencephalon, and several peripheral nerves. The initial clinical manifestations were dyspnoea and hyperventilation.

Case presentation

The patient presented to the hospital with fatigue, dyspnoea, and limb pain for over 7 months, accompanied by progressive breathlessness and unconsciousness in the last 6 days. Initial treatment with glucocorticoids for Guillain-Barre syndrome (GBS) proved ineffective in controlling the severe shortness of breath and hyperventilation, necessitating the use of ventilator-assisted ventilation. 18-Fluorodeoxyglucose positron emission tomography/computed tomography (18FDG PET/CT) showed that the basal ganglia, brainstem, and multiple peripheral nerves were thickened and metabolically active. There were atypical cells in the cerebrospinal fluid; the pathology indicated invasive B-cell lymphoma, demonstrating a propensity toward diffuse large B-cell lymphoma (DLBCL). After receiving chemotherapy, the patient regained consciousness and was successfully weaned off ventilator assistance but died of severe pneumonia.

Discussion

The early clinical manifestations of DLBCL lack specificity, and multifocal DLBCL complicates the diagnostic process. When a single primary disease cannot explain multiple symptoms, the possibility of DLBCL should be considered, and nervous system invasion should be considered when nervous system symptoms are present. Once nervous system involvement occurs in DLBCL, whether the central or peripheral nervous system, it indicates a poor prognosis.

Post-concussive syndrome to primary central nervous system lymphoma: An insidious presentation

Primary central nervous system lymphoma (PCNSL) and central neurogenic hyperventilation (CNH) are both rare occurrences, especially when associated with Epstein-Barr Virus (EBV). We report a case of an immunocompetent individual who presented to the emergency department (ED) with vague neurological symptoms found to have an EBV-associated PCNSL complicated by CNH. This rare occurrence had an insidious presentation initially mistaken for "post-concussive syndrome" at an outside ED. Insidious neurological malignancies, posterior strokes, intracranial hematomas, and other life-threatening pathologies should always be on the differential in patients presenting to the ED with falls with associated neurological symptoms, especially with unexplained blood gas abnormalities.

Anesthesia Considerations in Neurological Emergencies

Airway obstruction and respiratory failure are common complications of neurological emergencies. Anesthesia is often employed for airway management, surgical and endovascular interventions or in the intensive care units in patients with altered mental status or those requiring burst suppression. This article provides a summary of the unique airway management and anesthesia considerations and controversies for neurologic emergencies in general, as well as for specific commonly encountered conditions: elevated intracranial pressure, neuromuscular respiratory failure, acute ischemic stroke, and acute cervical spinal cord injury.

Central neurogenic hyperventilation in conscious patients due to CNS neoplasm: a case report and review of the literature on treatment

Background

Central neurogenic hyperventilation (CNH) is increasingly reported in conscious patients with a CNS neoplasm. We aimed to synthesize the available data on the treatment of this condition to guide clinicians in their approach.

Methods

We describe the case of a 39-year-old conscious woman with CNH secondary to glioma brainstem infiltration for whom hyperventilation was aborted with hydromorphone, dexamethasone, and brainstem radiotherapy. We then performed a review of the literature on the treatment of CNH in conscious patients due to a CNS neoplasm.

Results

A total of 31 studies reporting 33 cases fulfilled the selection criteria. The underlying neoplasm was lymphoma in 15 (45%) and glioma in 13 (39%) patients. Overall, CNH was aborted in 70% of cases. Opioids and sedatives overall seemed useful for symptom relief, but the benefit was often of short duration when the medication was administered orally or subcutaneously. Methadone and fentanyl were successful but rarely used. Chemotherapy was most effective in patients with lymphoma (89%), but not glioma (0%) or other neoplasms (0%). Patients with lymphoma (80%) and other tumors (100%) responded to radiotherapy more frequently than patients with glioma (43%). Corticosteroids were moderately effective. Subtotal surgical resection was successful in the 3 cases for which it was attempted.

Conclusion

Definitive treatment of the underlying neoplasm may be more successful in aborting hyperventilation. Variable rates of palliation have been observed with opioids and sedatives. Treatment of CNH is challenging but successful in a majority of cases.

A case of central neurogenic hyperventilation without tachypnoea

Central neurogenic hyperventilation (CNH) is a rare condition, with 37 cases reported in the literature to date. The underlying mechanisms remain unclear. Primary central nervous system lymphoma (PCNSL) is the most common cause of CNH, with 17 cases reported so far. Among these, CNH was usually accompanied by tachypnoea. Only two cases, including the present case, showed CNH with normal respiratory rate. Here, we present a case of PCNSL-induced CNH in a 60-year-old man. Magnetic resonance imaging of the brain demonstrated hyperintensity of the left cerebral cortex, basal ganglia, corona radiata, midbrain, and ventral pons on fluid-attenuated inversion recovery. The patient complained of dyspnoea and showed hyperventilation without tachypnoea on admission or during hospitalization. Examining CNH cases without tachypnoea and comparing those cases to cases of CNH with tachypnoea might provide new insights into the mechanisms of CNH. Moreover, it should be remembered that CNH can occur without tachypnoea.

Refractory Central Neurogenic Hyperventilation: A Novel Approach Utilizing Mechanical Dead Space

This report describes the successful management of a case of central neurogenic hyperventilation (CNH) refractory to high dose sedation by increasing the mechanical dead space. A 46-year-old male presented with a history of multiple neurological symptoms. Following an extensive evaluation, he was diagnosed with primary diffuse CNS lymphoma and started on high dose steroids. After initial symptomatic improvement, the patient developed increasing respiratory distress and tachypnea. He was intubated and transferred to the neurointensive care unit (neuro ICU). While in the ICU the patient remained ventilator dependent with significant tachypnea and respiratory alkalosis resistant to fentanyl and propofol. This prompted an attempt to normalize the PaCO₂ via an increase of the mechanical dead space. This approach successfully increased PaCO₂ and bridged the patient until ongoing therapy for the underlying disease resolved the pervasive breathing pattern typical of CNH. Further investigation is warranted to evaluate this strategy, which upon review of the literature appears underused.