Reply to Singh, G.D. Comment on "Dao et al. Retrospective Analysis of Real-World Data for the Treatment of Obstructive Sleep Apnea with Slow Maxillary Expansion Using a Unique Expansion Dental Appliance (DNA). Pathophysiology 2023, 30, 199-208".

In response to the commentary "Response to 'Retrospective analysis of real-world data for the treatment of obstructive sleep apnea with slow maxillary expansion'" [...].

Sleep Deprivation and Its Consequences.

OBJECTIVE: This article reviews the clinical, cognitive, behavioral, and physiologic consequences of sleep deprivation in relation to general neurology practice. LATEST DEVELOPMENTS: Despite being one of the most common sleep problems in modern society, the role of sleep deprivation is underrecognized and underestimated in clinical medicine and general neurology practice. The recognition, diagnosis, and management of sleep deprivation in neurologic practice have only recently received close attention. The consequences of sleep deprivation involve all aspects of general neurology practice, including individuals with neurologic disease, neurologists, communities, and health care systems. The identification and timely management of sleep deprivation symptoms may help to improve symptoms of underlying primary neurologic disorders. ESSENTIAL POINTS: This article emphasizes complexities related to the identification and evaluation of sleep deprivation in general neurology practice and describes the consequences of sleep deprivation. By recognizing sleep deprivation in patients with neurologic conditions, the neurologist can provide comprehensive care and contribute to improved clinical and neurologic outcomes.

Retrospective Analysis of Real-World Data for the Treatment of Obstructive Sleep Apnea with Slow Maxillary Expansion Using a Unique Expansion Dental Appliance (DNA).

In addition to mandibular advancement devices, dental expansion appliances are an important clinical approach for achieving an increased intra-oral space that promotes airflow and lessens the frequency or severity of apneic events in patients diagnosed with obstructive sleep apnea (OSA). It has been thought that dental expansion in adults must be preceded by oral surgery; however, in this paper, we examine the results of a new technique for slow maxillary expansion without any surgical procedures. The palatal expansion device, DNA (Daytime-Nighttime Appliance), was reviewed in this retrospective study, particularly regarding its effects on measurements of transpalatal width, airway volume, and apnea-hypopnea indices (AHI) as well as its common modalities and complications. The DNA effectively reduced AHI by 46% (p = 0.00001) and significantly increased both airway volume and transpalatal width (p < 0.00001). After DNA treatment, 80% of patients showed some improvement in AHI scores with 28% of patients having their OSA symptoms completely resolved. Compared to the use of mandibular appliances, this approach is intended to create a sustained improvement in airway management that can reduce or eliminate dependence on continuous positive airway pressure (CPAP) or other OSA treatment devices.

The mobile sleep medicine model in neurologic practice: Rationale and application.

Background: Undiagnosed obstructive sleep apnea (OSA) is prevalent in neurological practice and significantly contributes to morbidity and mortality. OSA is prevalent in US adults and causes poor quality sleep and significant neurocognitive, cardiovascular, and cerebrovascular impairments. Timely treatment of OSA reduces cardio-cerebrovascular risks and improves quality of life. However, most of the US population has limited systematic access to sleep medicine care despite its clinical significance. Focus: We discuss the importance of systematic screening, testing, and best-practice management of OSA and hypoventilation/hypoxemia syndromes (HHS) in patients with stroke, neurocognitive impairment, and neuromuscular conditions. This review aims to introduce and describe a novel integrated Mobile Sleep Medicine (iMSM) care model and provide the rationale for using an iMSM in general neurological practice to assist with systematic screening, testing and best-practice management of OSA, HHS, and potentially other sleep conditions. Key points: The iMSM is an innovative, patient-centered, clinical outcome-based program that uses a Mobile Sleep Medicine Unit-a "sleep lab on wheels"-designed to improve access to OSA management and sleep care at all levels of health care system. The protocol for the iMSM care model includes three levels of operations to provide effective and efficient OSA screening, timely testing/treatment plans, and coordination of further sleep medicine care follow-up. The iMSM care model prioritizes effective, efficient, and patient-centered sleep medicine care; therefore, all parties and segments of care that receive and provide clinical sleep medicine services may benefit from adopting this innovative approach.

The Role of the ACE2/MasR Axis in Ischemic Stroke: New Insights for Therapy.

Ischemic stroke remains the leading cause of neurologically based morbidity and mortality. Current stroke treatment is limited to two classes of FDA-approved drugs: thrombolytic agents (tissue plasminogen activator (tPA)) and antithrombotic agents (aspirin and heparin), which have a narrow time-window (<4.5 h) for administration after onset of stroke symptoms. While thrombolytic agents restore perfusion, they carry serious risks for hemorrhage, and do not influence damage responses during reperfusion. Consequently, stroke therapies that can suppress deleterious effects of ischemic injury are desperately needed. Angiotensin converting enzyme-2 (ACE2) has been recently suggested to beneficially influence experimental stroke outcomes by converting the vasoconstrictor Ang II into the vasodilator Ang 1-7. In this review, we extensively discuss the protective functions of ACE2-Ang (1-7)-MasR axis of renin angiotensin system (RAS) in ischemic stroke.

Human placenta mesenchymal stem cell protection in ischemic stroke is angiotensin converting enzyme-2 and masR receptor-dependent.

Thromboembolic stroke remains a major cause of neurological disability and death. Current stroke treatments (aspirin, tissue plasminogen activator) are significantly limited by timing and risks for hemorrhage which have driven researchers to explore other approaches. Stem cell-based therapy appears to be an effective option for ischemic stroke. Besides trans-differentiation into neural cells, stem cells also provide acute protection via paracrine signaling pathways through which releasing neuroprotective factors. We previously reported that intraperitoneal administration of human placenta mesenchymal stem cell (hPMSC) therapy upon reperfusion significantly protected the brain against middle cerebral artery occlusion (MCAO)-induced injury. In the present study, we specifically investigated the role of hPMSC-derived angiotensin converting enzyme-2 (ACE-2) in protection of MCAO-induced brain injury by measurement of brain tissue viability, cerebral blood flow, and neurological score. Here, we report for the first time that hPMSC expressing substantial amount of ACE-2, which mediates hPMSC protection in the MCAO model. Strikingly, we found that the protective effects of hPMSC in MCAO-induced brain injury could be attenuated by pretreatment of hPMSCs with MLN-4760, a specific inhibitor of ACE-2 activity, or by transfection of hPMSCs with ACE-2-shRNA-lentivirus. The hPMSC-derived ACE-2 specific protective mechanism was further demonstrated by administration of PD123319, an Angiotensin type-2 receptor antagonist, or A779, a MasR antagonist. Importantly, our study demonstrated that the protective effects of hPMSC in experimental stroke are ACE-2/MasR dependent and this signaling pathway represents an innovative and highly promising approach for targeted stroke therapy.

Autotitrating Bilevel Positive Airway Pressure in Large Vessel Steno-Occlusive Stroke Patients With Suspected Sleep Apnea: A Multicenter Randomized Controlled Study.

Background: We hypothesized that autotitrating bilevel positive airway pressure (auto-BPAP) favorably affects short-term clinical outcomes in hyperacute ischemic stroke. Methods: In a multicenter, randomized, controlled trial patients with large vessel steno-occlusive stroke and clinically suspected sleep apnea were allocated to auto-BPAP or standard stroke care alone. Auto-BPAP was initiated within 24 h from stroke onset and performed over 48 h during diurnal and nocturnal sleep. Sleep apnea was assessed using cardiorespiratory polygraphy. Primary endpoint was early neurological improvement on National Institutes of Health Stroke Scale (NIHSS) score at 72 h. Safety and tolerability of BPAP, functional independence [modified Rankin Scale (mRS) 0-2], stroke recurrence, and mortality at 90 days were assessed. Results: Due to low recruitment, the trial was prematurely stopped after 24 patients had been randomized (auto-BPAP, n = 14; control, n = 10): median baseline NIHSS 13 (5.5-18), 88% large vessel occlusion, and 12% large vessel stenosis. Polygraphy confirmed sleep apnea in 64% of auto-BPAP and 88% of control patients (p = 0.34). Adherence to auto-BPAP was achieved by 9 of the 14 (64%) patients. Between auto-BPAP and control patients, no differences were observed in early neurological improvement (median NIHSS change: -2.0, IQR = 7 points vs. -0.5, IQR = 3 points), 90 days functional independence (21 vs. 30%, p = 0.67), stroke recurrence (0 vs. 20%, p = 0.16), and death (14 vs. 20%, p = 1.0). No safety concerns were identified. Conclusions: In this prematurely terminated trial, auto-BPAP was safe but did not show an effect on short-term clinical outcomes in selected ischemic stroke patients. Its tolerability, however, may be limited in hyperacute stroke care and needs to be improved before larger trials are conducted. Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT01812993.

Human placental mesenchymal stem cells improve stroke outcomes via extracellular vesicles-mediated preservation of cerebral blood flow.

BACKGROUND: Besides long-term trans-differentiation into neural cells, benefits of stem cell therapy (SCT) in ischemic stroke may include secretion of protective factors, which partly reflects extracellular vesicle (EVs) released by stem cell. However, the mechanism(s) by which stem cells/EVs limit stroke injury have yet to be fully defined. METHODS: We evaluated the protection effect of human placenta mesenchymal stem cells (hPMSC) as a potential form of SCT in experimental ischemic stroke 'transient middle cerebral artery occusion (MCAO)/reperfusion' mice model. FINDINGS: We found for the first time that intraperitoneal administration of hPMSCs or intravenous hPMSC-derived EVs, given at the time of reperfusion, significantly protected the ipsilateral hemisphere from ischemic injury. This protection was associated with significant restoration of normal blood flow to the post-MCAO brain. More importantly, EVs derived from hPMSC promote paracrine-based protection of SCT in the MCAO model in a cholesterol/lipid-dependent manner. INTERPRETATION: Together, our results demonstrated beneficial effects of hPMSC/EVs in experimental stroke models which could permit the rapid "translation" of these cells into clinical trials in the near-term.

Obstructive sleep apnea intensifies stroke severity following middle cerebral artery occlusion.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is a sleep disorder caused by transient obstruction of the upper airway and results in intermittent hypoxia, sleep fragmentation, sympathetic nervous system activation, and arousal which can have an adverse effect on cardiovascular disease. It is theorized that OSA might intensify stroke injury. Our goal here was to develop a new model of experimental OSA and test its ability to aggravate behavioral and morphological outcomes following transient brain ischemia/reperfusion. METHODS: We used a 3D printed OSA device to expose C57BL6 mice to 3 h of OSA (obstructive apnea index of 20 events per hour) for three days. These mice were then subjected to ischemia/reperfusion using the middle cerebral artery occlusion model (MCAO) stroke and examined for overall survival, infarct size and neurological scoring. RESULTS: We found that OSA transiently decreased respiration and reduced oxygen saturation with bradycardia and tachycardia typical of human responses during apneic events. Brain injury from MCAO was significantly increased by OSA as measured by infarct size and location as well as by intensification of neurological deficits; mortality following MCAO was also increased in OSA animals. CONCLUSIONS: Our findings suggest that our new model of OSA alters respiratory and cardiovascular physiological functions and is associated with enhanced ischemia/reperfusion mediated injury in our non-invasive, OSA intensified model of stroke.

The Relationship Between Obstructive Sleep Apnea and Ruptured Intracranial Aneurysms.

STUDY OBJECTIVES: The role of obstructive sleep apnea (OSA) in the overall outcome of ruptured intracranial aneurysms (RIAs) is unknown. We have investigated the role of OSA in overall outcome of RIAs. METHODS: Data from 159 consecutive patients were retrospectively reviewed. A chi-square test and regression analysis were performed to determine the significant difference. A value of P < .05 was considered significant. RESULTS: The prevalence of OSA in RIAs was fivefold higher in the nonaneurysm patient group, P = .002. The number of patients with hypertension (P < .0001), body mass index ≥ 30 (P < .0001), hyperlipidemia (P = .018), chronic heart disease (P = .002) or prior ischemic stroke (P = .001) was significantly higher in the OSA group. Similarly, the number of wide-neck aneurysms (P < .0001) and aneurysm > 7 mm (P = .004), poor Hunt and Hess grade IV-V (P = .005), vasospasms, (P = .03), and patients with poor Modified Rankin Scale scores (3-6) was significantly higher in the OSA group (P < .0001). Interestingly, for the first time in univariate (P = .01) and multivariate (P = .003) regression analysis, OSA was identified as an individual predictor of unfavorable outcome of RIAs. In addition, hypertension (P = .04), smoking (P = .049), chronic heart disease (P = .01), and Hunt and Hess grade IV-V (P = .04) were revealed as predictors of poor outcome of RIAs. CONCLUSIONS: This is a novel study to determine the association between OSA and ruptured cerebral aneurysm in terms of comorbidities, size of aneurysm, severity of symptoms, and outcomes after treatment. In addition, for the first time, OSA is identified as a positive predictor of unfavorable outcome of RIAs.

Cardiorespiratory profiling reveals primary breathing dysfunction in Kcna1-null mice: Implications for sudden unexpected death in epilepsy.

Sudden unexpected death in epilepsy (SUDEP) is the leading cause of epilepsy-related mortality, but the relative importance of underlying cardiac and respiratory mechanisms remains unclear. To illuminate the interactions between seizures, respiration, cardiac function, and sleep that contribute to SUDEP risk, here we developed a mouse epilepsy monitoring unit (EMU) to simultaneously record video, electroencephalography (EEG), electromyography (EMG), plethysmography, and electrocardiography (ECG) in a commonly used genetic model of SUDEP, the Kcna1 knockout (Kcna1-/-) mouse. During interictal periods, Kcna1-/- mice exhibited an abnormal absence of post-sigh apneas and a 3-fold increase in respiratory variability. During spontaneous convulsive seizures, Kcna1-/- mice displayed an array of aberrant breathing patterns that always preceded cardiac abnormalities. These findings support respiratory dysfunction as a primary risk factor for susceptibility to deleterious cardiorespiratory sequelae in epilepsy and reveal a new role for Kcna1-encoded Kv1.1 channels in the regulation of basal respiratory physiology.

Restoration of sleep using a novel biomimetic protocol for adult OSA: Clinical case report.

BACKGROUND: A sleep study of a 56-year old male with excessive daytime sleepiness demonstrated an AHI of 16.4hr-1 with 13% of total sleep time in REM sleep and a mean oxygen desaturation (SpO2) of 86%. CLINICAL PRESENTATION: On intra-oral examination, it was found that the patient had maxillary hypoplasia and bilateral torus mandibularis. A 3D cone-beam CT (CBCT) scan was taken, and 28 craniofacial parameters were measured. Surgical reduction of the mandibular tori followed by biomimetic oral appliance therapy (BOAT) was initiated. After 14 months, a post-treatment CBCT scan revealed that 70% of parameters measured had improved. Therefore, another sleep study was performed with no device in the mouth. This follow-up home sleep test demonstrated that the AHI fell to 5.3hr-1hr; with 27% REM sleep, and a mean SpO2 of 93% without any device in the mouth. CONCLUSION: These findings suggest that BOAT might be able to restore sleep in certain adult cases.

Evaluation of Clinical Tools to Screen and Assess for Obstructive Sleep Apnea.

ABSTRACT: Obstructive sleep apnea (OSA) is a globally recognized medical condition, associated with development of long-term adverse health consequences, including cardiovascular disease, cerebrovascular disease, neurocognitive deficiencies, and vehicular and occupational accidents. OSA can be screened effectively, because it can be identified well before the manifestation of the aforementioned poor health and public safety consequences. Additionally, appropriate management of OSA includes an assessment of outcomes before and after therapeutic intervention initiation. OSA clinical screening and outcome assessment tools exist; however, a key existing knowledge gap is identifying which tools are most clinically relevant and efficient to use in clinical practice models. The American Academy of Sleep Medicine (AASM) commissioned a task force (TF) of sleep medicine experts to identify and evaluate current OSA screening and assessment tools for adult patients and determine if they are reliable, effective, and feasible for use in clinical settings. No single tool met all the TF's objective criteria and subjective evaluation for clinical validity and feasibility to be recommended by the AASM. The TF provides several suggestions for the development of new tools or modifications to existing tools that would enhance their functionality in adults.

Neurological Respiratory Failure.

West Nile virus infection in humans is mostly asymptomatic. Less than 1% of neuro-invasive cases show a fatality rate of around 10%. Acute flaccid paralysis of respiratory muscles leading to respiratory failure is the most common cause of death. Although the peripheral nervous system can be involved, isolated phrenic nerve palsy leading to respiratory failure is rare and described in only two cases in the English literature. We present another case of neurological respiratory failure due to West Nile virus-induced phrenic nerve palsy. Our case reiterates the rare, but lethal, consequences of West Nile virus infection, and the increase of its awareness among physicians.

Coexistence of obstructive sleep apnea worsens the overall outcome of intracranial aneurysm: a pioneer study.

OBJECTIVE Obstructive sleep apnea (OSA) is associated with the progression of abdominal and thoracic aortic aneurysms. However, the role of OSA in the overall outcome of intracranial aneurysms (IAs) has not yet been established. Authors of this report investigated the role of OSA in the overall outcome of IAs. METHODS Radiological and clinical data on patients (from 2010 through 2015) with confirmed IA were retrospectively reviewed. Significant differences between the OSA and non-OSA groups were determined using a chi-square test. Logistic regression analysis was performed to identify the predictors of an unfavorable IA outcome. RESULTS Among the 283 patients with confirmed IAs, 45 patients (16%) were positively screened for OSA, a proportion that was significantly higher than the prevalence of OSA in nonaneurysmal neurosurgical patients (4%, p = 0.008). The percentage of patients with hypertension (p = 0.018), a body mass index ≥ 30 kg/m2 (p < 0.0001), hyperlipidemia (p = 0.034), diabetes mellitus (p = 0.005), chronic heart disease (CHD; p = 0.024), or prior stroke (p = 0.03) was significantly higher in the OSA group than in the non-OSA group. Similarly, the percentage of wide-necked aneurysms (p = 0.00001) and patients with a poor Hunt and Hess Grade IV-V (p = 0.01) was significantly higher in the OSA group than in the non-OSA group. In addition, the percentage of ruptured aneurysms (p = 0.03) and vasospasms (p = 0.03) was significantly higher in the OSA group. The percentage of patients with poor modified Rankin Scale (mRS) scores (3-6) was significantly higher in the OSA group (p = 0.03). A separate cohort of patients with ruptured IAs showed similar results. In both univariate (p = 0.01) and multivariate (p = 0.04) regression analyses, OSA was identified as an individual predictor of an unfavorable outcome. In addition, hypertension and prior stroke were revealed as predictors of a poor IA outcome. CONCLUSIONS Complications of IA such as rupture and vasospasm are often the consequence of uncontrolled OSA. Overall outcome (mRS) of IAs is also affected by the co-occurrence of OSA. Therefore, the coexistence of OSA with IA affects the outcome of IAs. Obstructive sleep apnea is a risk factor for a poor outcome in IA patients.

Changing paradigm in the management of elderly patients with intracranial aneurysms: An institutional review.

Optimal treatment of intracranial aneurysms (IAs) in elderly patients has not yet been well established. We have investigated the clinical and radiological outcomes and predictors of unfavorable outcome of IAs in elderly patients. Radiological and clinical data of 85 elderly patients from 2010 through 2015 were retrospectively reviewed. Significant differences between the groups were determined by a chi-square test. Regression analysis was performed to identify the predictors of unfavorable outcome. Among the 85 patients with IAs, the number of patients with >7mm size aneurysm (p=0.01), diabetes mellitus (DM) (p=0.02), smoking (0.009) and Hunt and Hess grade 4-5 (p=0.003) was significantly higher in the ruptured group compared to the unruptured group. Similarly, the number of patients who underwent clipping was higher in the ruptured aneurysm group (p=0.01). The overall clinical outcome was comparatively better in the unruptured group (p=0.03); however, microsurgical clipping of aneurysms provides a significantly higher rate of complete aneurysmal occlusion (p=0.008). Overall, there was no significant difference in outcome in respect to treatment approach. In regression analysis, hypertension (HTN), obstructive sleep apnea (OSA), prior stroke, ruptured aneurysms and partial occlusion of aneurysms were identified as predictors of unfavorable outcome of IAs. Intracranial aneurysms in elderly patients reveals that endovascular treatment provides better clinical outcome; however, microsurgical clipping yields higher complete occlusion. Retreatment of residual aneurysms was comparatively more in the coiling group. Practice pattern has shifted from clipping to coiling for aneurysms in posterior circulation but not for aneurysms in anterior circulation.

Atypical presentation and outcome of cervicogenic headache in patients with cervical degenerative disease: A single-center experience.

OBJECTIVE: Cervicogenic headache affects a significant portion of the entire population. This type of headache especially with atypical presentation is often hard to diagnose and manage since its etiopathophysiology is not been yet well understood. We have investigated the prevalence of cervicogenic headache with atypical presentation and discussed the etiology of it, and the outcome of surgical intervention on this type of headache in patients with cervical degenerative disease. PATIENTS AND METHODS: Radiological and clinical data of 160 patients (from 2001 through 2016) were retrospectively reviewed. Significant differences between the groups were determined by chi-square test. Logistic regression analysis was performed to identify the predictors of unfavorable outcome. RESULTS: In this study, 10% of the patients had atypical presentation of cervicogenic headache. In overall cohort, after surgical intervention, there was significant improvement in symptoms and pain control, whether the presentation is typical or atypical. Sixty-one percent of the patients had no complaints, and 90% of the patients were headache-free (p<0.0001). Sixty-nine percent of the patients were free of neck, shoulder and extremity pain, and visual analogue scale pain score was reduced by 7 points (pre-op, 8.4 vs. last follow-up, 1.5, p<0.0001). However, number of patients with reduced headache was significantly higher in the group with typical presentation of headache (90.1%) compared to group with atypical (80%) presentation, p=0.04. In this study, female gender, smoking, obesity and depression were identified as predictors of overall unfavourable outcome. In addition, in a separate analysis, smoking and depression were revealed as risk factors for persistent headache. CONCLUSIONS: A notable portion of patients with cervicogenic headache can have an atypical presentation mimicking a primary type headache. However, cervicogenic headaches with atypical presentation can be difficult to diagnose and manage at the initial visit of the patients. Etiopathophysiology of this type of headache could be explained by the theories including discogenic, convergence and sensitization-desensitization theories. When cervicogenic headache is accompanied with CDD, performing ACDF or laminectomy would be the treatment of choice. Surgical intervention can also relieve the accompanying neck, shoulder and extremity pain with minimal complications. Lastly, outcomes of surgical intervention depend on the patients' morbidities including obesity, smoking and depression.

Exploration of screening practices for obstructive sleep apnea in stroke medical community: A pilot study.

BACKGROUND: Frequency of sleep-disordered breathing (SDB) among stroke and transient ischemic attack (TIA) patients ranges from 30-80% and is associated with poor neurological outcomes. Per current stroke prevention guidelines from American Heart Association/American Stroke Association (AHA/ASA), SDB is included in the list of modifiable risk factors for stroke and TIA prevention. Goal of our study is to determine screening practices for SDB in stroke medical community. METHODS: A web-based survey was sent to physicians taking care of stroke patients across North America and Europe. RESULTS: Among 112 total responses, 91 (81%) were stroke physicians, nine (8%) were general neurologists, nine (8%) were from other specialties and three (3%) were sleep medicine physicians. Majority of physicians (72%, n=81) do not use SDB screening questionnaires in their stroke patients. Epworth sleepiness scale is the most used among SDB questionnaires (24%, n=25/105), followed by Berlin sleep questionnaire (10%) and STOP-BANG questionnaire (7%). Only 13% of physicians use screening questionnaires in both in-patients and outpatients, whereas 21% use only in outpatients and 5% use only in acute stroke setting. Only 50% (n=56/111) of physicians would refer their stroke patients to a sleep medicine specialist when patients screen positive for SDB on questionnaires. CONCLUSION: Despite being an independent risk factor for stroke and TIA, majority of physicians in the pilot targeted cohort of medical professionals, who are involved in the management of stroke and TIA, do not screen these patients for SDB. Further work involving systematic, more detailed standardized surveys are needed to be developed to objectively evaluate and improve screening practices for SDB in national and international stroke medical communities.

Can We Assess Pulsus Paradoxus through Polysomnography in a Patient with Chronic Obstructive Pulmonary Disease and Sleep-Disordered Breathing?

ABSTRACT: Pulsus paradoxus (PP) is a decrease in systolic blood pressure greater than 10 mm Hg during inspiration that occurs in various medical conditions. Using polysomnography pulse oximetry signal, photoplethysmography variations of the amplitude of the pulse pressure within the respiratory cycle were observed. There is a proportional relationship between the changes of inspiratory waveform values and the generated PP. A 59-year-old male underwent polysomnography that showed sleep hypoxemia, obstructive sleep-disordered breathing (apnea hypopnea index [AHI] = 5.1and respiratory disturbance index [RDI] = 87.9), with variations of pulse pressure induced primarily by inspiration. The highest variations in the pulse wave were observed in NREM sleep during obstructive respiratory events and in biocalibration during nasal breathing. The lowest variations occurred after the correction of inspiratory obstructive events and during biocalibration when asked to hold his breath.

Traumatic Brain Injury and Behavior: A Practical Approach.

Traumatic brain injury (TBI) is a complex neurologic and neuropathologic process that may affect the patient's behavior permanently. Clinically, TBI is associated with a wide gamut of neurologic and psychiatric disorders, such as amnesia, cognitive decline, seizures, attention and concentration deficits, depression, manic behavior, psychosis, hostile and violent behavior, and personality alterations. Therapy and rehabilitative efforts should be designed based on the type of injury and the patient's specific needs. Gaining familiarity with the behavioral disorders outlined in this article and understanding how to identify and treat them plays a significant role in the management of patients with TBI.