Search Results (70)

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that affects motor neurons; respiratory problems are the leading cause of death and hospital admissions and are secondary to progressive weakness of the respiratory muscles and upper airway. Noninvasive ventilation (NIV) can increase survival, alleviate symptoms, reduce hospital admissions, and improve the quality of life of these patients. The key factor in respiratory management of patients with ALS is achieving effective NIV; ineffective NIV has a negative impact on survival, with a reduction of up to 50% compared to patients with an effective technique. The most common cause of ineffective NIV is air leaks; other causes include upper airway obstruction events, residual hypoventilation, hyperventilation, and upper airway obstruction secondary to an oronasal mask. Regular monitoring of the effectiveness of NIV is essential given its impact on survival; the key tools that detect the main problems are the presence of hypoventilation symptoms, arterial blood gases, nocturnal oximetry and capnography, and built-in ventilator software. Different measures have been proposed to address the ineffectiveness of NIV, such as fitting the mask to reduce air leaks, increasing ventilatory support for residual hypoventilation, decreasing ventilatory support for hyperventilation, or a trial with a nasal mask to address oronasal interface effects. In the case of obstruction, the most common measure is to increase positive expiratory pressure during NIV. These measures enable NIV to be effective in 58% of cases, achieving a survival rate similar to that of patients who have effective NIV from the outset. Full article

Background and Aims: Decreased cerebrovascular reactivity (CVR) in patients with significant internal carotid artery stenosis (ICAS ≥ 70%) is an independent risk factor for cerebral infarction. To evaluate CVR, changes in cerebral perfusion pressure and blood flow velocity (BFV) of the middle cerebral artery (MCA) can be estimated by CO₂- (hyperventilation—HV and breath-holding—BH) and pressure–flow-based (Common Carotid Artery Compression—CCC and Valsalva Maneuver—VM) stimuli. We used a multimodal approach to characterize CVR in patients before carotid endarterectomy (CEA). Methods: HV, BH, CCC, and VM tests were performed on 31, 26, and 34 patients. BFV of MCAs was monitored by transcranial Doppler, and continuous arterial blood pressure was registered non-invasively. CVR was compared between the operated significantly stenotic and the contralateral sides. Results: The extent of HV- and BH-induced CVR was similar, but the time to the lowest HV-induced BFV was shorter on the side with significant ICAS. The response to CCC was sensitive to hemodynamic asymmetry in the transient hyperemic response ratio and in the cumulative change in the (mean arterial blood pressure)/(mean BFV) ratio. In VM, the slope of BFV increased in the ascending (2b) phase, and the time to overshoot correlated with the side of the stenosis. Conclusions: These results suggest that in patients with significant ICAS, in addition to CO₂ reactivity measurements, a more complex estimation of CVR, by using hemodynamic tests (CCC and VM), should also be used to better quantify cerebral ischemic risk. Full article

Hypophosphatemia, defined as serum phosphate levels below 2.5 mg/dL, is a common yet underrecognized electrolyte disturbance in critically ill patients, with prevalence estimates reaching up to 80%. This review explores the intricate bidirectional relationship between hypophosphatemia and hyperventilation, emphasizing its profound implications for respiratory function and critical care management. Hypophosphatemia impairs oxygen delivery by depleting 2,3-diphosphoglycerate (2,3-DPG), disrupts central respiratory drive, and weakens respiratory muscles, leading to hyperventilation, ventilatory failure, and prolonged mechanical ventilation. Conversely, hyperventilation exacerbates hypophosphatemia through respiratory alkalosis, triggering intracellular phosphate shifts and metabolic cascades that rapidly deplete serum levels. This cycle creates significant challenges for ventilator weaning and increases morbidity and mortality. Underlying mechanisms include impaired ATP synthesis, altered chemoreceptor sensitivity, and systemic inflammatory responses. Hypophosphatemia-induced hyperventilation manifests as unexplained tachypnea and respiratory alkalosis, often misdiagnosed as anxiety or pain, while hyperventilation-induced hypophosphatemia contributes to diaphragmatic dysfunction and poor ventilatory performance. Common precipitating factors include refeeding syndrome, diabetic ketoacidosis, continuous renal replacement therapy, and malnutrition. Complications extend beyond respiratory dysfunction to include cardiac depression, immune dysfunction, prolonged ICU stays, and increased healthcare costs. Current diagnostic approaches rely on serum phosphate measurements, which poorly reflect total body stores due to significant intracellular shifts. Emerging biomarkers such as fibroblast growth factor 23 (FGF23) and advanced monitoring technologies, including continuous phosphate tracking, may enhance recognition. Treatment strategies emphasize targeted phosphate repletion based on severity, with intravenous supplementation and ventilatory support tailored to minimize complications. Preventive measures, including risk stratification, prophylactic supplementation, and ventilator management, are critical for high-risk populations. Despite advances, knowledge gaps persist in optimizing monitoring and repletion protocols, understanding genetic variations, and identifying ideal phosphate targets for improved respiratory outcomes. This review provides a comprehensive framework for recognizing and managing hypophosphatemia’s impact on respiratory dysfunction in critically ill patients. Adopting evidence-based interventions and leveraging emerging technologies can significantly improve clinical outcomes, reduce ICU complications, and enhance recovery in this vulnerable population. Full article

Background: Hyperventilation Syndrome (HVS) is a well-recognized physiological consequence of acute anxiety, often resulting in respiratory alkalosis and subsequent electrolyte imbalances. Among these, a reduction in ionized calcium levels can lead to neuromuscular irritability and electrocardiographic abnormalities such as QTc prolongation. Although well-documented in specific settings, including autism spectrum disorders and drug-induced crises, such complications are rarely described in otherwise healthy pediatric patients presenting with isolated anxiety episodes. This report aims to raise awareness of anxiety-driven somatic manifestations, particularly in the context of the rising prevalence of mental health disorders among children and adolescents. Methods: We report the case of a previously healthy 10-year-old girl presenting to the emergency department with acute agitation and hyperventilation. Clinical examination revealed neuromuscular symptoms, including Trousseau’s sign and flexion posture. Initial laboratory testing and arterial blood gas analysis indicated respiratory alkalosis with decreased ionized calcium levels, and a resting ECG showed QTc prolongation (510 ms). Treatment included intravenous midazolam, a balanced electrolyte solution, and oral bromazepam during intensive observation with cardiac monitoring. Results: The patient’s symptoms progressively improved following anxiolytic and supportive therapy. Electrolyte abnormalities normalized within 48 h, with complete resolution of the prolonged QTc (430 ms). No arrhythmias or other complications occurred. Outpatient psychological follow-up was arranged upon discharge. Conclusions: This case underscores the importance of considering anxiety as a primary etiology in pediatric patients with apparent metabolic or cardiac abnormalities. Early psychiatric recognition and targeted supportive care can prevent overtreatment and reduce the burden on emergency and cardiologic resources. Full article

Electroconvulsive therapy (ECT) is a non-pharmacological biological treatment method used to treat major depression, bipolar disorder, schizophrenia, catatonia, and some other psychiatric conditions. Despite its high effectiveness, it is often used when other methods, such as pharmacotherapy and psychotherapy, fail to improve treatment outcomes. The refinement of this particular therapy may increase the popularity of this method, and among the currently studied therapy modifiers is protocolised hyperventilation. Hyperventilation is implemented to improve ventilation and gas exchange, reduce shortness of breath, improve blood oxygenation, and prevent hypoxia. Research suggests that hyperventilation during ECT may prolong the duration of epileptic seizures, potentially enhancing the effectiveness of the therapy. However, research on hyperventilation during ECT still poses many questions regarding its benefits and side effects. Innovative studies on ECT with concomitant hyperventilation focus on monitoring parameters such as CO₂, EEG, and cardiovascular responses. Current research directions worth exploring also include the utilisation of modern ECT devices or determining the neurotrophin concentration to better understand the mechanism of action at the neurochemical level. The personalization of therapy, including adjustment of ECT parameters to patients’ specific symptoms, can reduce the risk of failure and increase effectiveness. Full article

Rett syndrome (RTT) is an X-linked neurodevelopmental disorder marked by neurological regression, autonomic dysfunction, seizures, and significant sleep and breathing abnormalities. About 80% of affected individuals, especially young children, experience sleep disturbances such as insomnia, sleep-disordered breathing, nocturnal vocalizations, bruxism, and seizures. Breathing irregularities during sleep—like apnea, alternating hyperventilation, and hypoventilation—are common, with both obstructive and central sleep apnea identified through polysomnography. This review focuses on the prevalent sleep disorders in children with Rett syndrome and highlights current recommendations for the management of sleep disorders. Full article

Introduction: Previous neuroimaging studies have reported structural brain alterations and local network hyperexcitability in terms of increased slow-wave electroencephalography (EEG) activity in patients with borderline personality disorder (BPD). In particular, intermittent rhythmic delta and theta activity (IRDA/IRTA) has drawn attention in mental health contexts due to its links with metabolic imbalances, neuronal stress, and emotional dysregulation—processes that are highly pertinent to BPD. These functional disturbances may be reflected in corresponding structural brain changes. The current study investigated cortical thickness and subcortical volumes in BPD and examined their associations with IRDA/IRTA events per minute, symptom severity, and neuropsychological measures. Methods: Seventy female BPD patients and 36 age-matched female healthy controls (HC) were included (for clinical EEG comparisons even 72 patients were available). IRDA/IRTA rates were assessed using an automatic independent component analyses (ICA) approach. T1-weighted MRI data were obtained using a MAGNETOM Prisma 3T system and analyzed with FreeSurfer (version 7.2) for subcortical structures and CAT12 for cortical thickness and global volume measurements. Psychometric assessments included questionnaires such as Borderline Symptom List (BSL-23) and Inventory of Personality Organization (IPO). Neuropsychological performance was evaluated with the Test for Attentional Performance (TAP), Culture Fair Intelligence Test (CFT-20-R), and Verbal Learning and Memory Test (VLMT). Results: Between-group comparisons exhibited no significant increase in IRDA/IRTA rates or structural abnormalities between the BPD and HC group. However, within the BPD group, cortical thickness of the right isthmus of the cingulate gyrus negatively correlated with the IRDA/IRTA difference (after minus before hyperventilation, HV; p < 0.001). Furthermore, BPD symptom severity (BSL-23) and IPO scores positively correlated with the thickness of the right rostral anterior cingulate cortex (p < 0.001), and IPO scores were associated with the thickness of the right temporal pole (p < 0.001). Intrinsic alertness (TAP) significantly correlated with relative cerebellar volume (p = 0.01). Discussion: While no group-level structural abnormalities were observed, correlations between EEG slowing, BPD symptom severity, and alertness with cortical thickness and/or subcortical volumes suggest a potential role of the anterior cingulate cortex, temporal pole, and cerebellum in emotion regulation and cognitive functioning in BPD. Future research employing multimodal EEG-MRI approaches may provide deeper insights into the neural mechanisms underlying BPD and guide personalized therapeutic strategies. Full article

Background/Objectives: In a patient suspected of having epilepsy, routine EEG primarily contributes to the recording of interictal epileptiform discharges (IEDs). Similarly, magnetic resonance imaging (MRI) has become the gold standard imaging technique for identifying epileptogenic structural brain abnormalities. Various EEG and MRI tools to improve epilepsy diagnosis will be presented. Methods: When the initial EEG fails to record IEDs, various EEG measures that can improve EEG performance are presented; a comprehensive epilepsy-targeted MRI protocol to identify, localize, and characterize an epileptogenic lesion will also be described. Results: Studies show that the initial routine EEG fails to record IEDs in approximately 47–50% of epileptic patients. To improve the yield of EEG, subsequent EEG recording should include sleep deprivation, sleep recording, prolonged hyperventilation, optimized light stimulation, addition of an inferior temporal electrode chain, extended EEG duration, and continuous video-EEG monitoring, all measures known to activate IEDs. Furthermore, MRI is interpreted as “normal” in many epilepsy patients, even when performed according to an epilepsy-specific protocol and evaluated by a specialized MRI reader. In such case, the use of the Harmonized Epilepsy Structural Sequence Imaging (HARNESS-MRI) protocol and other imaging tools will improve the detection of potential epileptic lesions, as described in this study. Conclusions: In a patient with a clinical diagnosis of epilepsy but a normal EEG and brain MRI, several options can improve the performance of subsequent EEG and MRI examinations, the subjects of this review. Full article

Background/Objectives: The Nijmegen Questionnaire (NQ) has been a prevalent screening tool for dysfunctional breathing for the past 40 years. Until recently, the validity of the NQ has been established for the general population with hyperventilation syndrome (HVS) and for individuals with asthma, but not for people with COPD. The aim of the study was to examine the validity and reliability of the NQ in individuals with COPD. Methods: Construct, convergent, divergent and discriminant validity as well as internal consistency reliability were examined in a sample of 84 people with stable COPD. Results: A three-factor solution with 16 items and 74.70% of explained variability was extracted through principal component analysis. High internal consistency (Cronbach alpha = 0.94) of the 16 NQ items was found. Significant differences were found between COPD individuals with and without DB (p < 0.001) and among people of all COPD levels of severity (p < 0.001). The value “>23” was found to detect the presence of DB, with 95.92% sensitivity and 94.29% specificity. Significant correlations were found between the total NQ score with BODE index (r = 0.81), Borg dyspnea scale (r = 0.47) and CAT (r = 0.49). The prevalence of DB for the specific sample was found to be 58.3%. Conclusions: The present study provided the first validity and reliability evidence for the NQ for people with stable COPD. Full article

Introduction: Epstein–Barr virus (EBV) usually causes mild, self-limiting, or asymptomatic infection in children, typically infectious mononucleosis. The severe course is more common in immunocompromised patients. Neurological complications of primary infection, reactivation of the latent infection, or immune-mediated are well-documented. However, few published cases of fatal EBV encephalitis exist. Case presentation We report a case of a 5.5-year-old immunocompetent girl with fulminant EBV encephalitis fulfilling the criteria for the recently proposed subtype Acute Fulminant Cerebral Edema: (AFCE). The child presented with fever, vomiting, altered mental status, and ataxia. Her initial brain CT (computed tomography) scan was normal. On day 2 she developed refractory status epilepticus requiring intubation, ventilation, and sedation for airway protection and seizure control. Magnetic resonance imaging (MRI) scan showed cytotoxic brain edema. Despite intensive treatment, including acyclovir, ceftriaxone, hyperosmotic therapy (3% NaCl), intravenous immunoglobulins (IVIG), corticosteroids, as well as supportive management, on day 5 she developed signs of impending herniation. Intensification of therapy (hyperventilation, deepening sedation, mannitol) was ineffective, and a CT scan demonstrated generalized brain edema with tonsillar herniation. EBV primary infection was confirmed by serology and qPCR in blood samples and post-mortem brain tissue. An autopsy was consistent with the early phase of viral encephalitis. Conclusions This case confirms that normal or non-specific CT and MRI scans do not exclude encephalitis diagnosis if clinical presentation fulfills the diagnostic criteria. The implementation of prophylactic anticonvulsants could improve outcomes. Intracranial pressure (ICP) monitoring should be considered in AFCE for better ICP management. Decompressive craniectomy might be a life-saving option in refractory cases. An encephalitis management algorithm is proposed. Full article

This study aims to report the dietary and daily management, clinical signs, complementary exams, and pathological findings related to an acute and fatal case of gastric dilatation and volvulus (GDV) in a captive Linnaeus’s two-toed sloth (Choloepus didactylus) in the Amazon Biome. An adult female sloth, rescued after being electrocuted, was housed at the Wildlife Section of the Veterinary Hospital (WSVH) of the Institute of Veterinary Medicine (IVM) at the Universidade Federal do Pará (UFPA). It was fed a diverse diet that included animal protein, fruits, vegetables, and greens, with vitamin and mineral supplementation. After five years, the sloth was found in its enclosure hyporesponsive, dehydrated, hypothermic, and hyperventilating, with an abdominal dilation of firm consistency. During emergency care, the animal died. Fecal samples collected two days before death were positive only for Clostridium perfringens type A. Necropsy findings included dilatation of the squamous gastric compartment due to gas accumulation, with necrotic and hemorrhagic mucosa, a 180–270° volvulus obstructing the gastroesophageal region, and intestinal mucosal hyperemia. Histopathology revealed marked congestion with hemorrhage and gastric mucosal necrosis, along with tertiary lymphoid follicles in the submucosa. To the authors’ knowledge, this is the first report of GDV in a sloth in Brazil. Further research is needed to develop appropriate approaches to GDV in captive sloths. Full article

Dogs, unlike humans, are equipped with a reduced number of sweat glands, which makes it difficult for them to dissipate heat, especially in conditions of intense activity that lead to a significant increase in body temperature. The study aims to investigate the metabolic differences between canine and human red blood cells (RBCs) and the hemoglobin (Hb) functionality focusing on their roles in heat dissipation. In detail, we evaluated the Band 3 protein (AE1) kinetic flux by observing that in canine red blood cells the anion exchange rate is higher than in humans (Rate Constant: 0.0438 min⁻¹ and 0.012 min⁻¹, respectively). Furthermore, we investigated the rate of ATP production and release to evaluate the possible variation of nucleotide concentration in the two species, observing a lower intracellular ATP concentration (101.80 μM and 297.90 μM) but a higher ATP release (3 μM and 2.65 μM) in canine RBCs compared to humans respectively. Subsequently, we evaluated the involvement of canine hemoglobin in heat dispersion; in detail, the ΔH= −5.15 Kcal/mol recorded in dog hemolysate at pH 7.5 shows an exothermic Hb-O₂ bond that may be useful for further dispersing heat from the lungs. The peculiar oxygen-binding properties of dog Hb may also promote oxygen release in hyperventilation characterized by alkaline pH. Full article

Manual ventilation, most commonly with a bag-valve mask, is a form of short-term ventilation used during resuscitative efforts in emergent and out-of-hospital scenarios. However, compared to mechanical ventilation, manual ventilation is an operator-dependent skill that is less well controlled and is highly subject to providing inappropriate ventilation to the patient. This article first reviews recent manual ventilation guidelines set forth by the American Heart Association and European Resuscitation Council for providing appropriate manual ventilation parameters (e.g., tidal volume and respiratory rate) in different patient populations in the setting of cardiopulmonary resuscitation. There is then a brief review of clinical and manikin-based studies that demonstrate healthcare providers routinely hyperventilate patients during manual ventilation, particularly in emergent scenarios. A discussion of the possible mechanisms of injury that can occur during inappropriate manual hyperventilation follows, including adverse hemodynamic alterations and lung injury such as acute barotrauma, gastric regurgitation and aspiration, and the possibility of a subacute, inflammatory-driven lung injury. Together, these injurious processes are described as manual-ventilation-induced lung injury (MVILI). This review concludes with a discussion that highlights recent progress in techniques and technologies for minimizing manual hyperventilation and MVILI, with a particular emphasis on tidal-volume feedback devices. Full article

Hyperventilation (HV) is an activation technique performed during clinical practices to trigger epileptiform activities, supporting the neurophysiological evaluation of patients with epilepsy. Although the role of HV has often been questioned, especially in the case of focal epilepsy, no studies have ever assessed how cortical structures respond to such a maneuver via intracranial EEG recordings. This work aims to fill this gap by evaluating the HV effects on the Stereo-EEG (SEEG) signals from a cohort of 10 patients with drug-resistant focal epilepsy. We extracted multiple quantitative metrics from the SEEG signals and compared the results obtained during HV, awake status, non-REM sleep, and seizure onset. Our findings show that the cortical connectivity, estimated via the phase transfer entropy (PTE) algorithm, strongly increases during the HV maneuver, similar to non-REM sleep. The opposite effect is observed during seizure onset, as ictal transitions involve the desynchronization of the brain structures within the epileptogenic zone. We conclude that HV promotes a conductive environment that may facilitate the propagation of epileptiform activities but is not sufficient to trigger seizures in focal epilepsy. Full article

State-of-the-art therapy improves the five-year survival rate of patients under the age of 20 with cranial and craniospinal tumors by up to 74%. The urgency of dealing effectively with late treatment-associated cardiovascular complications is rising. Objective: We aimed to assess echocardiographic parameters and exercise performance in subjects with a history of complex treatment for cranial and craniospinal tumors in childhood. Methods: the study of 48 subjects who underwent cranial and craniospinal irradiation for CNS tumors in childhood and 20 healthy age- and sex-matched volunteers was conducted. The examination included hormone studies, cardiopulmonary exercise testing, and, in the main group, echocardiography (ECHO). Results: In five (10.4%) patients, ECHO changes were detected after complex anti-cancer treatment: thickening and calcification of the aortic valve leaflets (2%), and reduction in the systolic LV and RV function (8% and 6%, respectively). Irradiation of various areas was a significant predictor for reduced exercise tolerance, hyperventilation at rest and upon exertion, and an increased ventilatory equivalent for carbon dioxide. Low exercise tolerance was associated with a younger age at the time of treatment initiation. Significant differences were noted between the control group and the childhood cancer survivors with endocrine disorders. Conclusions: The obtained data confirm the importance of regular cardiovascular and endocrine monitoring of this group of cancer survivors. Full article