Reduction In Oxygen Saturation Research Articles

CEREBRAL OXIMETRY AS A NEUROMONITORING TECHNIQUE DURING ORAL SANATION IN CHILDREN UNDER GENERAL ANESTHESIA ON AN OUTPATIENT BASIS

The article presents the results of assessing cerebral metabolism in children during oral cavity sanitation under conditions of general anaesthesia on an outpatient basis. The procedure was performed by using a non-invasive technique of neuromonitoring, cerebral oximetry, aimed at detecting changes in the cerebral oxygen supply. The method of cerebral oximetry enables to diagnose reduced oxygen saturation of cerebral tissues in early stage that significantly cuts down the risk of pathological organic changes in the brain and, as a consequence, decreases the risk of functional postoperative changes. It is noteworthy that rSO2 is within the upper normal limit (74.41% ± 2.08). This is explained by the peculiarities of the circulatory system in children and vascular walls in particular (developed capillary network, elasticity, and vascular permeability), as well as by the characteristics of the structure of the brain and increased oxygen consumption by cerebral neurons, which are in the stage of active development. It is important to stress that this figure is within the upper normal limit due to ↓rSO2 by 9.4% at the preoperative stage that can be explained by the high stressing, which in most cases is associated with "cryptogenic" phobias. This is a reasonable premise for administering anxiolytics prior dental intervention under general anaesthesia in an outpatient setting to avoid sharp fluctuations in cerebral oxygen saturation. The specific weight of ↓rSO2 in the preoperative stage in group of children is ↓ rSO2 (67.21%) in 24 (17.4%) children (7.18% relative to the total indicator of the identical group and 9.67% relative to the general group), who were at the renewal treated due to acute conditions (acute pulpitis, exacerbation of chronic periodontitis, periostitis). The period between dental interventions in these children did not exceed 2 weeks. This fact causes the necessity to limit the period of recurrent dental interventions to not less than two weeks. According to the results of the study, it has been found out that dental care under general anaesthesia on an outpatient basis while maintaining spontaneous breathing has time limits. It is advisable to perform general anaesthesia for 30 ± 10 minutes in children aged 0-3 years, for 40 ± 15 min. in children aged 3-12 years, and 60 ± 15 min. in children aged 12-18 years. The choice of dental treatment modes should be based on the time and possibility of a second visit. The term of planned dental surgery under general anaesthesia in an outpatient setting while maintaining spontaneous breathing after acute respiratory diseases requires at least two week period. In order to prevent the risk of complications during the oral sanitation at an outpatient setting under general anaesthesia, a period of scheduled dental recurrent interventions should be preformed not earlier than in two weeks.

The effect of reduced oxygen saturation during sleep on depression

Introduction: Numerous data suggest that episodes of breathing disorder during sleep are closely related to chronic cardiovascular and mental illnesses. Aim: In this study, we sought to find out how the decrease in oxygen saturation level and its duration during sleep are affected by the degree of depression and its extent. Method: Data of 76 persons were processed in the study. The oxygen saturation measured during sleep was obtained from data from a polysomnographic filter device. Data collection for depression symptoms was done with a validated questionnaire. The decrease of night oxygen saturation on the effect of the disease was illustrated by the odds ratio calculation. Results: The value below 90% of the average oxygen saturation during sleep time will more than double the risk of developing depression. It is also a risk factor for the severity of depression. Examining the duration of sleep time at reduced saturation, it mainly increases the chance of severe depression. Conclusions: Hypoxia during sleep and duration of hypoxic periods are a risk factor for the development of depression with therapeutic and diagnostic consequences. Orv Hetil. 2019; 160(20): 780-783.

Does High Ultrafiltration Volume Correlate to Occurrence of Desaturation in Patients Undergoing Hemodialysis?

Background: Hemodialysis is a metabolically stressful condition for patients that leads to reduced oxygen saturation and tissue perfusion. One of the identified drivers is a high ultrafiltration volume (UFV). Concurrently, central venous oxygen saturation (ScvO2) is a marker for global tissue hypoxia that has been used in cases of sepsis and trauma to guide fluid therapy. In dialysis patients with a central venous catheter (CVC) access ScvO2 is accessible. Here we intend to delineate the relationship of UFV to desaturation during dialysis through the measurement of ScvO2. Methods: PICO was formulated from a clinical case, and a literature search was conducted in Pubmed, Embase, Scopus, and Cochrane. Selected studies were then critically appraised using harm/etiology worksheet from CEBM1 for validity, importance, and applicability. Results: Studies by Harrison, et al., Zhang, et al. and Rotondi, et al. were chosen for answering our PICO. Harrison, et al. reported a relation of r: -0.680, p:0.015 between UFV and ScvO2. While, Zhang, et al. utilized retrospective data of Critline Monitor (CLM) reading of dialysis patients and reported a negative 0.3% slope of ScvO2 over corrected UFV (cUFV). Whilst, Rotondi, et al. demonstrated that in 20 patients separated equally to exclusively dialysis or ultrafiltration and both caused lowering of ScvO2, but only the former was statistically significant. Discussion: The mechanism of relationship may include incapability of plasma refill rate to compensate for the fluid shift during ultrafiltration, resulting in lower cardiac preload and stroke volume which is detrimental in patients who are natively prone to suffer from reflex bradycardia and intradialytic hypotension. Studies have shown that episodes of hypoxemia in dialysis patients translate to worse prognosis. Conclusion: ScvO2 is inversely proportional to UFV. As such, monitoring for ScvO2 in dialysis patients will be beneficial to prevent end-organ ischemia.

Features of the clinic and diagnosis of chronic heart failure in patients with chronic obstructive pulmonary disease

To elucidate clinical and diagnostic features of chronic heart failure (CHF) in patients with chronic obstructive pulmonary disease (COPD). The study included 239 patients with COPD and 42 patients with CHF without COPD. The first subgroup consisted of 60 patients with a history of myocardial infarction (MI) and the second subgroup consisted of 79 patients without a history of MI. A general clinical examination, EchoCG, measurements of N-terminal pro B-type natriuretic peptide (NT-proBNP), galectin 3, and high-sensitivity C-reactive protein (hsCRP) were performed for all patients. The risk group for excluding HF as a cause of progressive dyspnea in COPD patients consisted of patients with the bronchitic phenotype who belonged to GOLD groups C and D with frequent exacerbations, increased hsCRP, reduced oxygen saturation, and impaired exercise tolerance. Patients with a history of MI constituted a special group of risk. Measuring specific biomarkers, primarily BNP or NT-proBNP, is recommended to confirm the presence/absence of CHF and to evaluate CHF severity in patients with these risk factors. A combination of COPD and CHF produces a number of clinical and, specifically, diagnostic problems, which have not been completely solved so far.

Body Composition Abnormalities in Adults with a Fontan Circulation

Background and methods: The Fontan circulation exists with no subpulmonary ventricular pump. We aimed to characterise body composition in this setting and to explore possible pathophysiological associations. Participants were recruited for dual x-ray absorptiometry (DXA), cardiopulmonary exercise testing, echocardiography and biochemical assessment. Results: Twenty-eight people with a Fontan circulation (26 ± 7 years) were recruited. All were NYHA Class I/II with 46% males. Skeletal muscle mass (relative appendicular lean mass Z-score) was reduced (−1.49 ± 1.10, p ≤ 0.001); 68% had muscle mass deficits (Z-score <−1), 39% were in sarcopenic range (Z-score <−2) and only 32% had normal muscle mass (Z-score ≥−1). Skeletal muscle mass correlated with % predicted oxygen pulse (stroke volume surrogate, r = 0.50, p = 0.007), % predicted maximum handgrip strength (r = 0.53, p = 0.004), systolic function (r = 0.42, p = 0.024) and was inversely related with haemoglobin (r = −0.39, p = 0.038), likely reflecting reduced oxygen saturations, which result in compensatory erythrocytosis. Appendicular lean mass was independently associated with peak VO2 (β = 73 mL/min, p ≤ 0.001). Overall, by DXA, only 50% had normal range adiposity, 14% had moderate adiposity, 32% had high adiposity, and 4% had low adiposity. In contrast, 32% had above normal range BMI. The level of agreement between BMI and DXA for adiposity categorisation was only fair (kw = 0.53). Conclusion: Young adults with a Fontan circulation have a body composition profile characterised by skeletal muscle deficiency and are predisposed to increased adiposity, which is underestimated by BMI. Superior skeletal muscle mass, which is independently related with peak exercise capacity, is associated with lower haemoglobin levels and greater systolic function.

TESTICULAR BUT NOT TESTICULAR: A GERM CELL TUMOR PRESENTING AS ACUTE RESPIRATORY FAILURE

SESSION TITLE: Medical Student/Resident Pulmonary Manifestations of Systemic Disease 1 SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/09/2018 01:15 PM - 02:15 PM INTRODUCTION: Germ cell tumors (GCTs) of the testes account for 95% of the testicular tumors. The most aggressive and least common type of the GCTs is choriocarcinoma (CC). It is a highly malignant tumor and patients typically present with early metastases, with lungs being the most common site. Given the rarity of the disease and its unusual presentation, CC remains a challenging diagnosis often leading to high mortality in young males. We present a very rare entity of CC known as the 'burned out phenomenon' in which an extra gonadal GCT develops without traces of neoplasm in the testes. CASE PRESENTATION: A 41-year-old previously healthy male presented with one month history of shortness of breath and cough. He was tachypneic and tachycardic with reduced oxygen saturation of 86% on room air. Physical exam revealed crackles in bilateral lungs. Chest x- ray showed diffuse bilateral pulmonary opacities concerning for malignancy. CT chest revealed a large left upper lobe mass measuring 10x9x12 cm and innumerable round pulmonary nodules in both lungs. Patient became progressively tachypneic requiring BiPAP and he was admitted to the ICU. His hypoxia and tachypnea worsened to the extent of requiring invasive ventilation, but patient opted against it and support was continued on the BiPAP. Further workup for his lung metastases with CT of the abdomen-pelvis revealed extensive metastatic disease involving the liver and adrenal glands. CT guided biopsy of the lung revealed necrotic tissue. There was a suspicion for GCT and ultrasound of the testes was done but no discrete testicular lesion was found. Tumor markers revealed a B-HCG level that was significantly elevated at 156,000 IU with normal alpha feto-protein. Based on the biopsy findings, elevated B-HCG levels, normal alpha feto-protein, and the metastatic presentation, the patient was diagnosed with CC. Despite multiple lines of chemotherapy, patient died within a month due to rapid disease progression with further metastases to brain. DISCUSSION: CC does not require histological confirmation and in rare cases no testicular lesion can be found. The primary tumor is thought to regress spontaneously in the testes, so the initial presentation is a manifestation of the metastases. Clinical picture, specific serum markers, and imaging findings can be diagnostic. In the early stage of advanced CC patients usually have no obvious clinical signs. The pulmonary symptoms can range from a mild cough, shortness of breath or hemoptysis. The latter usually presents in severe cases with multiple metastases. This was a challenging diagnosis due to absence of a palpable testicular mass, no tissue proven diagnosis, and rapid progression of the disease. CONCLUSIONS: Our case underlines the importance of having a high suspicion for CC in young males presenting with pulmonary symptoms and chest-x ray findings concerning for malignancy. Early chemotherapy is recommended. Reference #1: Horwich A, Shipley J, Huddart R. Testicular germ-cell cancer. Lancet. 2006;367:754–65 Reference #2: Ohno, Y., Yamauchi, T., Ueda, T., Aizawa, T., Kawakami, S., Tachibana, Y., Tsuchiya, S. (1993). A case of testicular choriocarcinoma achieving pathological complete response by “COMPE” chemotherapy, consisting of cisplatin, vincristine, methotrexate, peplomycin, and etoposide. Acta Urologica Japonica, 39(2), 183–187 DISCLOSURES: No relevant relationships by Muhamad Alhaj Moustafa, source=Web Response No relevant relationships by Nebiyu Biru, source=Web Response No relevant relationships by Rama Hritani, source=Web Response No relevant relationships by James Shaw, source=Web Response No relevant relationships by Anusha Vakiti, source=Web Response

Clinical features and treatment of macrolide-resistant Mycoplasma pneumoniae pneumonia in children

To study the clinical features of macrolide-resistant Mycoplasma pneumoniae pneumonia and its treatment regimens in children. The samples of throat swab or bronchoalveolar lavage fluid were collected from 136 children with Mycoplasma pneumoniae pneumonia. Quantitative real-time PCR was used to detect 2063/2064 A:G mutation in 23S rRNA, and according to such results, the children were divided into drug-resistance group with 81 children and sensitive group with 55 children. The two groups were compared in terms of age composition, respiratory symptoms, extrapulmonary complications, laboratory markers, imaging changes, treatment regimens, and length of hospital stay. Compared with the sensitive group, the drug-resistance group had significantly longer duration of pyrexia and severe fever, a significantly higher percentage of children with reduced blood oxygen saturation, and significantly higher levels of alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) (P<0.05). The conventional azithromycin treatment had a good clinical effect in the sensitive group, while corticosteroid therapy was usually needed in the drug-resistance group. Macrolide-resistant Mycoplasma pneumoniae infection cannot be identified based on a single clinical feature, but prolonged duration of pyrexia and severe fever, reduced blood oxygen saturation, and increased ALT and LDH can suggest the presence of this disease. Azithromycin combined with glucocorticoids may be a good treatment regimen for children with macrolide-resistant Mycoplasma pneumoniae pneumonia.

Effect of pre-hospital care on prognosis of hypertensive intracerebral hemorrhage

Objective To investigate the effect of pre-hospital emergency on prognosis of patients with hypertensive cerebral hemorrhage. Methods From January 2016 to March 2017, 66 patients of hypertensive cerebral hemorrhage in Yuncheng Emergency Center were randomly divided into control group(routine treatment, 33 cases) and observation group(pre-hospital emergency, 33 cases)according to the digital table.The first aid efficiency, incidence of complications, quality of life and rescue result of the two groups were compared. Results The onset to the emergency department time, emergency department preliminary processing time, the relevant departments to do special inspection time, specialist diagnosis and treatment time, total emergency time in the observation group were (19.36±2.05)min, (15.13±2.41)min, (12.26±3.42)min, (8.20±1.21)min, (51.52±5.41)min, respectively, which were shorter than those in the control group[(35.26±2.52)min, (26.36±2.73)min, (17.25±4.12)min, (12.23±2.23)min, (84.26±4.56)min], there were statistically significant differences between the two groups(t=28.12, 17.72, 5.35, 9.12, 26.58, all P<0.05). The incidence rates of gastrointestinal bleeding, reduced blood oxygen saturation, central high fever, hypostatic pneumonia in the observation group were 0.00%, 3.03%, 3.03%, 6.06%, respectively, which were lower than those in the control group (12.12%, 21.21%, 18.18%, 24.24%)(χ2=4.26, 5.12, 4.00, 4.24, all P<0.05). After the condition was stable, the mental health score, emotional function score, physiological body function score, pain score, physiological function score, social function score of the observation group were (82.36±1.52), (84.36±2.43), (81.56±2.10), (83.64±2.54), (85.21±3.46), (84.59±3.26), respectively, which were higher than those of the control group[(68.53±2.57), (70.26±3.25), (69.64±3.56), (68.52±2.49), (69.12±3.23), (70.31±2.26)], there were statistically significant differences between the two groups(t=26.61, 19.96, 16.57, 24.42, 19.53, 20.68, all P<0.05). The rescue success rate of the observation group was 100.00%, which was higher than 78.79% of the control group, there was statistically significant difference between the two groups(χ2=7.83, P<0.05). Conclusion Pre-hospital care can effectively improve the prognosis of hypertensive intracerebral hemorrhage. Key words: Intracranial hemorrhage, hypertensive; Emergency medical services; Prognosis

Endotracheal suction in intensive care: A point prevalence study of current practice in New Zealand and Australia

BackgroundDespite the evidence and available guidelines about endotracheal suction (ETS), a discrepancy between published guidelines and clinical practice persists. To date, ETS practice in the adult intensive care unit (ICU) population across New Zealand and Australia has not been described. ObjectiveTo describe ICU nurses' ETS practice in New Zealand and Australia including the triggers for performing endotracheal suction. MethodsA single day, prospective observational, binational, multicentre point prevalence study in New Zealand and Australian ICUs. All adult patients admitted at 10:00 on the study day were included. Main outcome measuresIn addition to patient demographic data, we assessed triggers for ETS, suction canister pressures, use of preoxygenation, measures of oxygenation, and ETS at extubation. ResultsThere were 682 patients in the ICUs on the study day, and 230 were included in the study. Three of 230 patients were excluded for missing data. A total of 1891 ETS events were performed on 227 patients during the study day, a mean of eight interventions per patient. The main triggers reported were audible (n = 385, 63%) and visible (n = 239, 39%) secretions. Less frequent triggers included following auscultation (n = 142, 23%), reduced oxygen saturations (n = 140, 22%), and ventilator waveforms (n = 53, 9%). Mean suction canister pressure was −337 mmHg (standard deviation = 189), 67% of patients received preoxygenation (n = 413), and ETS at extubation was performed by 84% of nurses. ConclusionSome practices were inconsistent with international guidelines, in particular concerning patient assessment for ETS and suction canister pressure.

Effects of reduced water exchange rate and oxygen saturation on growth and stress indicators of juvenile lumpfish (Cyclopterus lumpus L.) in aquaculture

Lumpfish (Cyclopterus lumpus) is currently used as cleaner fish in Norwegian Atlantic salmon (Salmo salar) farming to control parasitic lice on salmon. The need for high numbers of lumpfish necessitates intensive farming of this species but very limited knowledge is available on the environmental requirements of lumpfish in culture. The present study was therefore carried out to investigate the tolerance of lumpfish to varying water exchange rates and oxygen saturations. Four triplicated treatment groups were established at different water exchange rates, which caused oxygen saturations of 55% (0.7Lmin−1), 69% (1.2Lmin−1), 81% (1.9Lmin−1) and 96% (6Lmin−1). Decreasing water exchange rate and oxygen saturations negatively affected growth, even in the fish groups held at 81% oxygen saturation. The fish group held at 55% oxygen saturation had almost no growth in body mass and showed sign of fin-infections and were terminated halfway through the experiment. A high workload associated with oxygen extraction and reduced appetite is considered the reason for reduced growth at lower oxygen saturations. While plasma cortisol levels in the groups held at 81 and 96% oxygen saturation corresponded to those considered typical for unstressed fish (<10ngmL−1), the levels of plasma cortisol of fish in the 69 and 55% oxygen saturation groups were above 20ngmL−1 in November, indicating a state of chronic stress. A fast, albeit weak, cortisol response to stressors in the lumpfish was confirmed in a separate, 2h long acute handling and hypoxia experiment. Lack of differences between treatments in plasma lactate levels indicates that the lumpfish reduced their food intake and locomotory activity sufficiently to avoid resorting to anaerobic metabolism when exposed to reduced oxygen saturations. It is concluded that the juvenile lumpfish is sensitive to reduced water oxygen saturations and that oxygen saturations below 80% in aquaculture should be avoided.

Pulmonary haemodynamics and gasometric parameters associated with exercise induced oxygen desaturation in idiopathic pulmonary fibrosis

BackgroundPatients with idiopathic pulmonary fibrosis (IPF) usually presented with exercise induced oxygen desaturation (EID). We hypothesize that pulmonary function tests (PFTs), pulmonary haemodynamics, and gasometric parameters may contribute to EID. ObjectiveRandomized, double blind, prospective study conducted to evaluate different parameters that may contribute to EID in IPF. Patients and methodsThirty-five patients with stable IPF were enrolled in this study. Resting PFTs, arterial blood gases, echocardiography, and incremental cardiopulmonary exercise testing (CPET) were done for all patients. Desaturated patients (DS) were those with reduced oxygen saturation ⩾4% in comparison to resting value and post exercise SaO2 ⩽88%, the remaining patients were considered non desaturated (NDS) group. ResultsNearly half of patients had EID (17/35); it was observed in those who had lower FVC%, FEV1%, DLCO%, Resting PaO2, Resting PaCO2, higher mPAP with statistically significant difference between DS & NDS. DLCO ⩽25 had the highest specificity (100%), and mPAP ⩾25 had the highest sensitivity (88.9%) among functional and heamogasometric parameters in detection of EID. ConclusionExercise induced oxygen desaturation in IPF can be predicted from PFTs and haemogasometric parameters.

Airplane Headache

Airplane headache is a rare disorder, but recent reviews suggest it may be indeed underreported. Symptoms are stereotypic with the most outstanding feature being its occurrence during airplane travel. Sinus barotrauma together with reduced oxygen saturation and humidity of the cabin air may be responsible for this condition. Most patients can be successfully treated with simple analgesics or NSAIDs.

Effects of aeration, sediment grain size and burial on stream litter breakdown and consumer performance: a microcosm study

Turbulence and aeration are reduced in many streams during low-flow periods as a consequence of drought or water abstraction, thus affecting invertebrate interactions and pivotal ecosystem processes such as the breakdown of organic matter (OM). These effects can be larger in the hyporheic zone (HZ), the ecotone connecting the surface stream and groundwater, especially when fine sediments reduce hydraulic conductivity. In addition, OM breakdown in the HZ could depend on the availability of OM in the benthic zone (BZ), because the latter would not only be a more accessible, and thus preferred, food resource, but also more easily scoured downstream. In a laboratory microcosm experiment of 28 days duration, we manipulated aeration, sediment size and location of OM (either all buried or half buried with half on the surface, simulating the HZ and BZ respectively). Six mayfly (Habroleptoides) individuals and four stonefly (Capnioneura) individuals were enclosed in each microcosm and the consumption of OM was measured. Lack of aeration reduced oxygen saturation from 94 to 66%, reducing OM consumption particularly on the surface, in contrast with our expectations. As hypothesised, the availability of surface OM significantly reduced invertebrate consumption of buried OM. Habroleptoides performed better than Capnioneura, especially in fine sediments. The results suggest that reduced turbulence can affect invertebrate trophic interactions as well as the decomposition of OM, depending on sediment grain size and the location of OM.

Influence of Oxygen Saturation and Age on Relaxation Time of Gray and White Matter and Diffusion Tensor Imaging Parameters in Children with Cardiac Malformations

The aim of this article is to investigate the influence of reduced arterial oxygenation on cerebral gray and white matter T2* time and parameters of diffusion tensor imaging (DTI) in children with cardiac malformations. In 23 patients examined by magnetic resonance imaging (3T), parameters were correlated to oxygen saturation and age (regression analysis). Reduced oxygen saturation correlated significantly to gray matter T2* time (p ≤ 0.01), whereas fractional anisotropy, mean diffusivity, and radial diffusivity correlated to age (p ≤ 0.005) but not to oxygenation. To conclude, gray matter T2* time might be used as a surrogate parameter to estimate oxygenation, and oxygenation does not influence the evaluation of DTI parameters.

Sleep, lung function, and quality of life in patients with myasthenia gravis: A cross-sectional study

The purpose of this study was to investigate the physiological variables of lung function, respiratory muscle strength, and sleep in clinically stable patients with myasthenia gravis. This was a prospective cross-sectional study conducted in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement. Patients adhering to the eligibility criteria were consecutively recruited from the Research Department of Neuromuscular Diseases at the Federal University of Sao Paulo and the Department of Neurology at Santa Casa de Misericordia of Sao Paulo and were referred to the Nove de Julho University Sleep Laboratory (Sao Paulo, Brazil). The study included 25 patients (21 female) with a mean age of 45.28 ± 12.33 years. Only one patient exhibited a restrictive ventilatory pattern. The maximum ventilatory pressures observed were considerably reduced in most patients as compared to reference values. In sleep studies, the patients exhibited significantly reduced oxygen saturation, reduced rapid eye movement sleep time, increased non-rapid eye movement stage 3 sleep, and considerable apnoea/hypopnoea indexes. Clinically stable patients with myasthenia gravis exhibit a high prevalence of sleep-disordered breathing, significant reductions in maximum ventilatory pressures, and impairment of health-related quality of life.

Size restricted silymarin suspension evokes integrated adaptive response against acute hypoxia exposure in rat lung

Despite its extraordinary antioxidant capacity, the clinical usage of silymarin has remained restricted to amelioration of hepatic pathology. Perhaps its low bioavailability and uneven bio-distribution, owing to its poor aqueous solubility, are two main causes that have dampened the clinical applicability and scope of this preparation. We took these two challenges and suggested an unexplored application of silymarin. Apart from liver, two of the most susceptible vital organs at the highest risk of oxidative stress are brain and lung, especially during reduced oxygen saturation (hypoxia) at anatomical level. Hypoxia causes excess generation of radicals primarily in the lungs as it is the first organ at the interphase of atmosphere and organism making it the most prone and vulnerable to oxidative stress and the first responder against hypobaric hypoxia. As our first objective, we improved the silymarin formulation by restricting its size to the lower threshold and then successfully tested the prophylactic and therapeutic action in rat lung challenged with simulated hypobaric hypoxia. After dose optimization, we observed that 50mg/kg BW silymarin as size restricted and homogenous aqueous suspension successfully minimized the reactive oxygen species and augmented the antioxidant defense by significant upregulation of catalase and superoxide dismutase and reduced glutathione. Moreover, the well-established hypoxia markers and proteins related to hypoxia adaptability, hif1a and VEGF were differentially regulated conferring significant reduction in the inflammation caused by hypobaric hypoxia. We therefore report,the unexplored potential benefits of silymarin for preventing high altitude associated pathophysiology further paving its road to clinical trials.

Cerium oxide nanoparticles promote neurogenesis and abrogate hypoxia-induced memory impairment through AMPK-PKC-CBP signaling cascade.

Structural and functional integrity of the brain is adversely affected by reduced oxygen saturation, especially during chronic hypoxia exposure and often encountered by altitude travelers or dwellers. Hypoxia-induced generation of reactive nitrogen and oxygen species reportedly affects the cortex and hippocampus regions of the brain, promoting memory impairment and cognitive dysfunction. Cerium oxide nanoparticles (CNPs), also known as nanoceria, switch between +3 and +4 oxidation states and reportedly scavenge superoxide anions, hydrogen peroxide, and peroxynitrite in vivo. In the present study, we evaluated the neuroprotective as well as the cognition-enhancing activities of nanoceria during hypobaric hypoxia. Using polyethylene glycol-coated 3 nm nanoceria (PEG-CNPs), we have demonstrated efficient localization of PEG-CNPs in rodent brain. This resulted in significant reduction of oxidative stress and associated damage during hypoxia exposure. Morris water maze-based memory function tests revealed that PEG-CNPs ameliorated hypoxia-induced memory impairment. Using microscopic, flow cytometric, and histological studies, we also provide evidences that PEG-CNPs augmented hippocampus neuronal survival and promoted neurogenesis. Molecular studies revealed that PEG-CNPs promoted neurogenesis through the 5′-adenine monophosphate-activated protein kinase–protein kinase C–cyclic adenosine monophosphate response element-binding protein binding (AMPK-PKC-CBP) protein pathway. Our present study results suggest that nanoceria can be translated as promising therapeutic molecules for neurodegenerative diseases.

Rare Case of Methemoglobinemia Complicating Pregnancy.

A patient at 38 weeks of gestation when taken for emergency cesarean section had her oxygen saturation of 66 to 70% (by saturation probe on monitor) in operation theatre. She was otherwise asymptomatic but her oxygen saturation was persistently low on the monitors. Her arterial blood gas analysis showed all parameters to be normal. Her electrocardiography was normal. Her surgery was imperative but due to her reduced oxygen saturation she became a high-risk case. In presence of senior consultants of anesthesia and gynecology and under high-risk consent she had an uneventful cesarean delivery. Physician and cardiologist opinions were sought thereafter. The outcomes and the results of our efforts to find the etiology of her reduced saturation on monitors despite being clinically asymptomatic lead to the disclosure of this rare hemoglobinopathy. Mother and baby had uneventful course after delivery and were discharged well.

Evaluating the Role of Reduced Oxygen Saturation and Vascular Damage in Traumatic Brain Injury Using Magnetic Resonance Perfusion-Weighted Imaging and Susceptibility-Weighted Imaging and Mapping.

The cerebral vasculature, along with neurons and axons, is vulnerable to biomechanical insult during traumatic brain injury (TBI). Trauma-induced vascular injury is still an underinvestigated area in TBI research. Cerebral blood flow and metabolism could be important future treatment targets in neural critical care. Magnetic resonance imaging offers a number of key methods to probe vascular injury and its relationship with traumatic hemorrhage, perfusion deficits, venous blood oxygen saturation changes, and resultant tissue damage. They make it possible to image the hemodynamics of the brain, monitor regional damage, and potentially show changes induced in the brain's function not only acutely but also longitudinally following treatment. These methods have recently been used to show that even mild TBI (mTBI) subjects can have vascular abnormalities, and thus they provide a major step forward in better diagnosing mTBI patients.

Is restless legs syndrome associated with chronic mountain sickness?

BackgroundRestless legs syndrome (RLS) and chronic mountain sickness (CMS) share physiological traits. Our objective was to explore a possible association between RLS and CMS. MethodsWe carried a cross-sectional study with male subjects living between 4100 and 4300 m above sea level. Participants underwent a clinical interview, physical examination, electrocardiographic (EKG) recording, and spirometry. We classified subjects into CMS, Limbo, and healthy high-altitude dwellers (hHAD), according to their Quinghai score and hematocrit levels. We applied the “Paradigm of questions for epidemiological studies of RLS,” The International Restless Leg Syndrome Study Group Scale, and the Pittsburgh Sleep Quality Index. Logistic regression analysis was used to determine the association between variables. ResultsSeventy-eight male subjects were included. Forty subjects were hHAD, 23 were CMS patients, and 15 participants were considered as Limbo. CMS and Limbo subjects had a higher frequency of RLS (p < 0.05). Limbo subjects had the highest severity score for RLS. There were no differences in age, body mass index (BMI), or tobacco use between RLS patients and non-sufferers. In the multivariate analysis, CMS was not associated with RLS diagnosis. Oxygen saturation (p = 0.019), poor sleep quality (p < 0.01), and Quinghai score of ≥6 (p = 0.026) were independently associated with RLS diagnosis. ConclusionsOur results did not show a direct association between RLS and CMS; however, RLS was associated with reduced oxygen saturation. Hence, RLS could represent an early clinical manifestation of hypoxia, or, in CMS natural history, an early sign of maladaptation to high altitude.