Mean SaO2 Research Articles

P3563The influence of circadian patterand obstructive sleep apnean of blood pressure in nocturnal arrhythmias in hypertensive patients

Abstract Introduction There is growing evidence suggesting hypertension is related to the occurrence of arrhythmias. When occurring predominantly during the night, two potential entities commonly present in hypertensive patients could be related with increased arrhythmogenesis: (1) the lack of normal nocturnal dipping of blood pressure (BP) (non-dipping pattern of hypertension) or (2) obstructive sleep apnea (OSA). Thus, nocturnal arrhythmias (NAs) can identify hypertensive patients with OSA and/or non-dipping pattern, both related with adverse outcomes. Aims To determine if NAs are related with non-dipping hypertension, OSA or both. Methods We studied hypertensive patients who performed ambulatory blood pressure monitoring (ABPM) and also polysomnography and 24-hour Holter monitoring. Non-dipping pattern was considered when nocturnal BP reduction was inferior to 10%. Based on Holter monitoring, NAs were present when atrial fibrillation, frequent premature atrial contractions (PACs) (>30 PACs/hour), runs of >4 consecutive PACs, frequent premature ventricular contractions (PVCs) (>30PVCs/hour) or runs of >4 consecutive PVCs were present predominantly during sleeping hours. During polyssonography, apnoea/hypopnoea index (AHI) and oxygen saturation (SaO2) were analysed. Moderate to severe OSA was considered when AHI >15. Results We studied 104 patients [median age 62 (54–70) years, 65% male): 42 (40%) had moderate to severe OSA (median AHI=11 (6–26), mean SaO2=94% (92–95)] and 64 (61%) were non-dippers. NAs occurred in 18 patients (17%) and they were independently associated with AHI (Odds Ratio (OR) for a one unit increase 1.04, 95% confidence interval (CI) 1.01–1.07, p=0.03) but not with SaO2 (OR 0.96, CI 0.78–1.19, p=0.73) nor non-dipping pattern (OR 1.23, CI 0.38–3.98, p=0.72). No interaction was found between OSA and non-dipping hypertension (p=0.35). In patients with dipping pattern (n=40), AHI was higher in NAs patients comparing with no NAs patients (median AHI 29 versus 10, p=0.04), while in those with non-dipping pattern (n=64), AHI was not statistically different between patients with and without NAs (21 versus 11, p=0.12) (figure). Figure 1 Conclusion In this population of hypertensive patients, the presence of NAs was associated with OSA severity (i.e AHI), but not with the non-dipping pattern of hypertension. The importance of obstructive events in arrhythmogenesis seemed to be more pronounced in dipping patients, suggesting the abnormal high blood pressure during the night may also have some impact on NAs in non-dipping patients. Overall, our results suggest that OSA screening should be considered when nocturnal arrhythmias are detected in hypertensive patients, but ABPM should not be forgotten since multiple mechanisms can be involved in nocturnal arrhythmogenesis.

Subcutaneous maternal resveratrol treatment increases uterine artery blood flow in the pregnant ewe and increases fetal but not cardiac growth.

Substrate restriction during critical developmental windows of gestation programmes offspring for a predisposition towards cardiovascular disease in adult life. This study aimed to determine the effect of maternal resveratrol (RSV) treatment in an animal model in which chronic fetal catheterisation is possible and the timing of organ maturation reflects that of the human. Maternal RSV treatment increased uterine artery blood flow, fetal oxygenation and fetal weight. RSV was not detectable in the fetal circulation, indicating that it may not cross the sheep placenta. This study highlights RSV as a possible intervention to restore fetal substrate supply in pregnancies affected by placental insufficiency. Suboptimal in utero environments with reduced substrate supply during critical developmental windows of gestation predispose offspring to non-communicable diseases such as cardiovascular disease (CVD). Improving fetal substrate supply in these pregnancies may ameliorate the predisposition these offspring have toward adult-onset CVD. This study aimed to determine the effect of maternal resveratrol (RSV) supplementation on uterine artery blood flow and the direct effects of RSV on the fetal heart in a chronically catheterised sheep model of human pregnancy. Maternal RSV treatment significantly increased uterine artery blood flow as measured by phase contrast magnetic resonance imaging, mean gestational fetal and as well as fetal weight. RSV was not detectable in the fetal circulation, and mRNA and protein expression of the histone/protein deacetylase SIRT1 did not differ between treatment groups. No effect of maternal RSV supplementation on AKT/mTOR or CAMKII signalling in the fetal left ventricle was observed. Maternal RSV supplementation is capable of increasing fetal oxygenation and growth in an animal model in which cardiac development parallels that of the human.

Hook Breathing Facilitates SaO2 Recovery After Deep Dives in Freedivers With Slow Recovery.

To facilitate recovery from hypoxia, many freedivers use a breathing method called “hook breathing” (HB) after diving, involving an interrupted exhale to build up intrapulmonary pressure. Some divers experience a delay in recovery of arterial oxygen saturation (SaO2) after diving, interpreted as symptoms of mild pulmonary edema, and facilitated recovery may be especially important in this group to avoid hypoxic “blackout.” We examined the influence of HB on recovery of SaO2 in freedivers with slow recovery (SR) and fast recovery (FR) of SaO2 after deep “free immersion” (FIM) apnea dives to 30 m depth. Twenty-two male freedivers, with a mean (SD) personal best in the discipline FIM of 57(26) m, performed two 30 m deep dives, one followed by HB and one using normal breathing (NB) during recovery, at different days and weighted order. SaO2 and heart rate (HR) were measured via pulse oximetry during recovery. The SR group (n = 5) had a faster SaO2 recovery using HB, while the FR group (n = 17) showed no difference between breathing techniques. At 105 s, the SR group reached a mean (SD) SaO2 of 95(5)% using HB, while using NB, their SaO2 was 87(5)% (p < 0.05), and 105–120 s after surfacing SaO2 was higher with HB (p < 0.05). In SR subjects, the average time needed to reach 95% SaO2 with HB was 60 s, while it was 120 s at NB (p < 0.05). HR was similar in the SR group, while it was initially elevated at HB in the FR group (p < 0.05). We conclude that HB efficiently increases SaO2 recovery in SR individuals, but not in the FR group. The proposed mechanism is that increased pulmonary pressure with HB will reverse any pulmonary edema and facilitate oxygen uptake in divers with delayed recovery.

Azaperone and xylazine: A pharmacological combination to facilitate captive deer management for red brocket deer (Mazama americana).

The care and management of deer in captivity is challenging, especially in the case of red brocket deer (Mazama americana), whose routine management using physical restraint is difficult. Our study evaluated the effects of azaperone and xylazine combination for immobilizing red brocket deer and allow for the standard capture and handling protocols (e.g., biological material, horn cutting, and trimming) to be conducted safely. Six adult, captive, red brocket deer received an intramuscular injection of either 1 mg/kg azaperone and 0.5 mg/kg xylazine (AX0.5) or 1 mg/kg azaperone and 1 mg/kg xylazine (AX1.0). Sedation latency, sternal recumbency, safe handling, and quality of the sedation were evaluated to provide an overview of how the immobilizing drugs affected managing the species in captivity. Additionally, heart rate, respiratory rate, mean arterial pressure, rectal temperature, pH, PaO2, PaCO2, SaO2, HCO3-, BE, Na+, K+ and serum lactate were also measured. The latency period of the animals in the AX0.5 group was greater than that of the animals in the AX1.0 group (7 ± 6.6 min vs. 5 ± 2.0 min), as was the time for them to assume sternal recumbency (12 ± 9.7 min vs. 6 ± 3.1 min). However, the time after the initial dose at which the animals could safely be handled (14 ± 4.5 min vs. 12 ± 5.2 min), and the time until the end of the safe handling period (75 ± 12.3 min vs. 85 ± 6.8 min) were similar for both groups. Animals in both groups showed physiological stability during all evaluations, but hypoxemia was observed in one animal in each group. We conclude that both drug combinations are safe and effective at sedating red brocket deer in captivity and suggest that the procedure be performed with oxygen supplementation to reduce the potential for hypoxia.

Effects of obstructive sleep apnea on inflammatory markers in patients with acute coronary syndrome

Objective To examine the prevalence of obstructive sleep apnea (OSA) in patients with acute coronary syndrome (ACS), and to evaluate the relationship of OSA with inflammatory biomarkers in ACS patients. Methods Patients with ACS treated at Beijing Anzhen Hopital from June 2015 to May 2017 were enrolled. Subjects were evaluated for OSA by sleep study, and were divided into a normal-mild OSA group (Apnea Hypopnea Index, AHI < 15 times/h) and a moderate-severe OSA group (AHI≥15 times/h). Laboratory examination and sleep study were monitored to analyze the effects of OSA on biomarkers by LSD-t test, Mann-whitney U test, or Chi-square test. Correlation analysis was performed to analyze the association of OSA with high sensitivity C-reactive protein (hs-CRP) by Spearman correlation anaylsis. Results A cohort of 836 patients with ACS were enrolled including 408 patients in the normal-mild OSA group and 428 patients in the moderate-severe OSA group. The levels of leukocyte(×109L) [7.78 (6.33, 9.86) vs 7.29 (6.01, 9.16), P=0.006], neutrophils(×109L) [5.05 (3.84, 7.23) vs 4.80 (3.74, 6.66), P=0.044], monocytes(×109L) [0.42 (0.33, 0.54) vs 0.39 (0.31, 0.51), P=0.033], hs-CRP(mg/L) [3.18 (1.10, 11.52) vs 1.78 (0.65, 6.46), P<0.01], fibrinogen(g/L) [3.17 (2.87, 3.74) vs 2.97 (2.59, 3.50), P=0.002], and uric acid(μmol/L) [360 (302, 422) vs 341(283, 407), P=0.006] in the moderate-severe OSA group were significant higher than those in the normal-mild OSA group. AHI (correlation coefficient=0.171, R2=0.020, P<0.01), ODI (correlation coefficient = 0.201, R2=0.027, P<0.01), and TSaO2 < 90% (correlation coefficient = 0.105, R2=0.005, P<0.01) were positively correlated with hs-CRP; minimal SaO2 (correlation coefficient=-0.100, R2=0.001, P=0.008) and mean SaO2 (correlation coefficient = -0.127, R2= 0.006, P<0.01) were negatively correlated with hs-CRP. Conclusions For patients with ACS, the level of inflammatory markers in the moderate-severe OSA group is significantly higher than that in the normal-mild OSA group. Hs-CRP is significantly associated with the severity of OSA. Diagnosis and monitoring of OSA should be considered in ACS management in the future. Key words: Acute coronary syndrome; Obstructive sleep apnea; Inflammatory marker; C-reactive protein

DECREASED NOCTURNAL MEAN OXYGEN SATURATION WAS ASSOCIATED WITH HYPERHOMOCYSTEINEMIA

Objective: To observe the relationship between plasma Homocysteine (Hcy) level and nocturnal sleep parameters in patients with hypertension. Design and method: A total of 1,663 patients admitted to the department of hypertension of xinjiang uygur autonomous region people's hospital from 2005 to 2010 were selected as observation objects, observation objects was divided into three groups according to the tri-sectional quantiles of plasma Hcy level.(Group A:Hcy<=10.74umol/L, Group B:10.74umol/L<Hcy<=16.24umol/L, Group C:Hcy>16.24umol/L). All subjects underwent polysomnography (PSG) to analyze and compare the general characteristics and nighttime sleep parameters (AHI, AI, SaO2 min, SaO2 mean, N1, N2, N3, N4, REM, ODI3, ODI4, TS90%) of patients in different groups. Multivariate Logistic regression was used to analyze the relationship between nocturnal sleep parameters and plasma Hcy. Results: Plasma Hcy increased gradually in patients with non, mild, moderate and severe OSA(12.23umol/L,12.6umol/L,13.14umol/L,13.66umol/L, P = 0.023). The differences of AHI, SaO2 min (%), SaO2 mean (%), N3 (%), shallow sleep stage (%), deep sleep stage (%), OD3 (times /h), OD4 (times /h), and ts90% were statistically significant in the three groups. Multiple Logistic regression analysis showed that after adjusting for gender, age, smoking and drinking history, the risk of hyperhomocysteinemia increased gradually with the decrease of mean blood oxygen saturation(OR1 = 1.039, P1 = 0.813. OR2 = 1.418, P2 = 0.011) Conclusions: With the aggravation of OSA, the plasma Hcy level increases in the patients with hypertension. The lower the average blood oxygen saturation at night, the higher the risk of hyperhomocysteinemia..

Repeated freediving – An efficient and safe method to rescue subjects trapped in cars underwater

A method based on repeated freediving was developed to rescue subjects trapped in cars underwater – a scenario leading to 5–6 annual deaths in Sweden, and thousands globally. We determined rescue time and whether the divers were at risk of hypoxic blackout. Cars containing 5 kg negatively buoyant rescue-dummies strapped with seatbelts were placed on 5 m and 8 m depth. Eight freediving-instructors made 230 freedives, working in pairs with one diver always at the surface. For each rescue, two freedivers, equipped with mask, snorkel, fins, weight-belt, wetsuit and a buoy with belt-cutter and glass-breaker freedived alternating in turns between the divers. They accomplished a maximum of one of the following tasks per dive; (1) Finding the car; (2) Marking car with buoy; (3) Opening door/crushing window. (4) Opening/cutting belt; (5) Retrieving dummy to surface; (6) Transporting dummy to shore. Dummies were retrieved to shore from 5 m depth within a mean (SD) duration of 4 min 16 s (1 min 36 s) and from 8 m within 6 min 22 s (2 min 13 s; P < 0.05). Mean dive duration was 28(7)s (14–46 s), with 3 dives over 40 s duration. Freedivers arterial oxygen saturation (SaO2) levels were measured in dives of 30, 35, 40 and 45 s using pulse oximetry. Mean (SD) SaO2 at 20 s after surfacing was 90% for 45 s dives. This allows rapid recovery and gives a safety margin to the 50% SaO2 level when divers may risk blackout. We concluded that repeated freediving is efficient for rescuing victims trapped in cars underwater within their survival time, and following recommended methods and dive durations, rescue divers are not exposed to risk.

The value of red blood cell distribution width in the evaluation of patients with obstructive sleep apnea hypopnea syndrome

Objective:To investigate the relationship between red blood cell distribution width (RDW) and severity of obstructive sleep apnea hypopnea syndrome (OSAHS). Method:A total of 112 patients with OSAHS who were diagnosed by PSG monitoring were selected as OSAHS group, and 61 healthy subjects with matched age, gender and BMI were selected as the control group. The peripheral venous blood of all subjects was collected in the morning, and relevant hematological indexes such as RDW, white blood cell count, red blood cell count, hemoglobin, mean red blood cell volume, and platelet count were obtained. Result:The RDW level in the OSAHS group was significantly higher than that in the control group. The RDW value increased gradually with the severity of OSAHS and was positively correlated with AHI(r=0.259), the mean SaO₂ (r=-0.279), the lowest SaO₂( r=-0.328), BMI(r=0.203) and negatively correlated with sleep time(r=-0.204). Conclusion:The elevated level of RDW may be an indicator of the severity of OSAHS. Since RDW is usually included in the complete blood count, it can provide an economical and practical indicator to initially assess the condition of OSAHS patients and prioritize polysomnography monitoring.

Cardiovascular Parameters in a Swine Model of Normobaric Hypoxia Treated With 5-Hydroxymethyl-2-Furfural (5-HMF).

Introduction:The consequences of low partial pressure of O2 include low arterial O2 saturations (SaO2), low blood O2 content (CaO2), elevated mean pulmonary artery pressure (PAP), and decreased O2 consumption VO2. 5-hydroxymethyl-2-furfural (5-HMF) binds to the N-terminal valine of hemoglobin (HgB) and increases its affinity to O2. We used an instrumented, sedated swine model to study the effect of 5-HMF on cardiovascular parameters during exposure to acute normobaric hypoxia (NH).MethodsTwenty-three sedated and instrumented swine were randomly assigned to one of three treatment groups and received equal volume of normal saline (VEH), 20 mg/kg 5-HMF (5-HMF-20) or 40 mg/kg 5-HMF (5-HMF-40). Animals then breathed 10% FiO2 for 120 min. Parameters recorded were Cardiac Output (CO), Mean Arterial Blood Pressure (MAP), Heart Rate (HR), Mean Pulmonary Artery Pressure (PAP), SaO2 and saturation of mixed venous blood (SvO2). The P50 was measured at fixed time intervals prior to and during NH.Results5-HMF decreased P50. In the first 30 min of NH, treatment with 5-HMF-20 and 5-HMF-40 resulted in a (1) significantly smaller decrement in SaO2 and SvO2, (2) significantly lower HR and CO, and (3) smaller increase in PAP compared to VEH. In the 120 min of NH there was a trend toward improved mortality with 5-HMF treatment.Conclusion5-HMF treatment decreased P50, improved SaO2, and mitigated increases in PAP in this swine model of NH.

Clinical features of heart failure with reduced ejection fraction in patients with obstructive sleep apnea syndrome

Aim of the research: to estimate the clinical features of chronic heart failure with a reduced ejection fraction in patients with obstructive sleep apnea compared with patients without sleep breathing disorders and to establish the relationships of clinical symptoms, anthropometric dates with the degree of hypoxic disorders during sleep.Materials and methods. 152 patients with chronic heart failure were enrolled in our open, prospective, non-randomized study. The control group consisted of 57 patients with obstructive sleep apnea without heart failure. A general clinical examination, anthropometric measurements, questionnaires, cardio-respiratory monitoring, echocardiography, the assessment of NT-proBNP were conducted to all participants in the study.Results. Patients from main group compared with control group were older (by 15.6 %, p&lt;0.05), had a higher body mass index and degree of obesity (by 16,9 %, p&lt;0.05 and 22.1 %, p&lt;0,05), had a longer history of arterial hypertension (by 36.3 %, p&lt;0.01), ischemic heart disease (by 23.6 %, p&gt;0.05), AF (by 16.0 %, p&gt;0.05), diabetes (by 25.3 %, p&lt;0.003). According results of correlation analysis in patients with heart failure and obstructive apnea a significant negative relationship apnea-hypopnea index with age (r=–0.418; p&lt;0.001), ejection fraction (r=–0.376; p&lt;0.01) and a direct link with body mass index (r=+0.512; p&lt;0.003) were found. Mean SaO2 significantly correlated with ejection fraction (r=–0.212; p&lt;0.05), duration of arterial hypertension (r=–0.417; p&lt;0.001), the level of office systolic arterial pressure (r=–0.351; p&lt;0.01) and the level of office diastolic arterial pressure (r=–0.331; p&lt;0.01).Conclusions. The prevalence of obstructive sleep apnea in patients with heart failure with reduced ejection fraction is 40.1 %, while 55.7 % of patients have severe obstructive sleep apnea. Patients with heart failure with reduced ejection fraction and obstructive sleep apnea are older, have a higher body mass index; they more often have comorbid pathologies in their medical history, namely, arterial hypertension, coronary heart disease, atrium fibrillation, and diabetes mellitus. According results of a correlation analysis, a significant relationships of apnea-hypopnea index with age (r=–0.418; p&lt;0.001), ejection fraction (r=–0.376; p&lt;0.01) and body mass index (r=+0.512 p&lt;0.003) were found

Retinal oxygen saturation in 1461 healthy children aged 7-19 and its associated factors.

PurposeThe aim of the present study was to investigate age‐specific normative retinal oxygen saturation values and explore the associated factors in healthy Chinese school‐aged children with different refractive statuses.DesignPopulation‐based observational cross‐sectional study.MethodsChildren aged 7–19 years were enrolled. Each participant underwent a series of comprehensive ocular examinations, including axial length (AL), cycloplegic refraction and Oxymap T1 imagery following cycloplegia. The acquired oximetry images were measured, and the values of the retinal oxygen saturation parameters were calculated. The independent factors of the retinal oxygen saturation were analysed using multiple linear regression. The oxygen saturation of retinal arteries (SaO2) and veins (SvO2) as well as the differences between the arteries and veins (AVD) were measured as the main outcomes.ResultsIn total, 1461 participants were included in the study. The mean age of the participants was 12.1 ± 3.2 years, and 53.0% were boys. The mean SaO2, SvO2 and AVD values were 83.7 ± 6.4%, 50.1 ± 5.4% and 33.6 ± 5.4%, respectively, and the values increased with age. Girls had higher SvO2 and lower AVD than boys (p < 0.05). The Pearson correlation coefficients among spherical equivalent (SE) and SaO2, SvO2 and AVD were −0.372, −0.203 and −0.240, respectively (all p < 0.001), while the correlations between AL and SaO2, SvO2 and AVD were 0.276, 0.106 and 0.221, respectively (all p < 0.001). The myopia group had significantly higher SaO2, SvO2 and AVD than the emmetropia and hyperopia groups (p < 0.001), but the high myopia group had lower SaO2 and SvO2 than the moderate myopia group. When age, gender, body mass index (BMI), intraocular pressure (IOP) and axial length (AL) were included as factors in the multiple regression, older age was associated with higher SaO2, SvO2 and AVD, while longer AL was associated with higher SaO2 and AVD. Gender was an independent factor predicting SvO2, while gender and BMI were the independent factors predicting AVD. Age explained more variance than AL in SaO2, SvO2 and AVD.ConclusionsOur population‐based study provides age‐specific profiles of retinal oxygen saturation in Chinese children and adolescents. Older age and longer AL were important independent factors of increased retinal oxygen saturation.

Outcomes of Single Ventricle Patients Undergoing the Kawashima Procedure: Can We Do Better?

Current technology advances in virtual surgery modeling and computational flow dynamics allow preoperative individualized computer-based design of Fontan operation. To determine potential role of those innovations in patients undergoing hepatic vein incorporation (HVI) following Kawashima operation, we retrospectively examined historic cohort of patients who underwent HVI following Kawashima with focus on regression of pulmonary arteriovenous malformations (PAVMs). Twenty-two children with single ventricle and interrupted inferior vena cava underwent Kawashima operation (2002-12). Twenty-one (96%) patients had left atrial isomerism and 21 (96%) had undergone prior first-stage palliation. Clinical outcomes were examined. Mean O2 saturation (SaO2) increased from 77% ± 8% to 85% ± 6% ( P = .002) after Kawashima. Fifteen (68%) patients developed PAVMs. Eighteen patients underwent HVI (median age and interval from Kawashima: 4.4 and 3.7 years, respectively). Mean SaO2 prior to HVI was 77% ± 8% and increased to 81% ± 10% at the time of hospital discharge ( P = .250), with five patients requiring home oxygen. On follow-up, mean SaO2 increased to 95% ± 4% ( P < .001). Overall ten-year survival following Kawashima was 94%. A large number of patients develop PAVMs and subsequent cyanosis after Kawashima operation. Early following HVI, SaO2 is commonly low and insignificantly different from that prior to HVI. Although SaO2 will improve on follow-up in most patients, a number of patients continue to have low saturations, indicating incomplete resolution of PAVMs. Given the heterogeneity of those patients and lack of preoperative predictors for complete PAVM regression, our findings suggest a role for virtual surgery to determine optimal individual procedure design that would provide even distribution of hepatic blood flow to both pulmonary arteries.

Effect of rewarming in oxygenation and respiratory condition after neonatal exposure to moderate therapeutic hypothermia

BackgroundTo assess changes in clinical condition and oxygenation in neonates after rewarming following moderate therapeutic hypothermia (MTH) for neonatal encephalopathy. MethodsRetrospective study of 28 neonates receiving MTH in a tertiary neonatal intensive care unit in Israel. We compared pre-and 24 h post-rewarming arterial oxygen saturation (SaO2) as measured by the blood gases analyzer, pulse-oximetry saturation (SpO2), and cardio-respiratory condition. ResultsThe SpO2 declined from 96.9% (±2.9) before rewarming to 95.2% (±2.6) after rewarming (p < 0.001). Twelve neonates (42.9%) had clinical respiratory impairment (needing higher respiratory support or had new onset desaturations). In 16 neonates (57.1%) with no change in respiratory support after rewarming, SpO2 decreased from 98.3 ± 1.9% to 95.6 ± 3.0% (p < 0.001) and SaO2 decreased from 97.1 ± 1.7% to 96.0 ± 2.3% (p = 0.002). The mean SpO2 decrease was greater than mean SaO2 decrease (2.63 ± 1.8 and 1.1 ± 1.3 respectively, p = 0.021). ConclusionNeonates who underwent MTH showed reduction in oxygenation after rewarming either by decreasing SpO2 or increasing FiO2 requirements. The SpO2 decline was larger than the SaO2 decline. We suggest careful monitoring of neonates after rewarming.

Prothrombotic state in children with obstructive sleep apnea

ObjectiveIncreased blood coagulation might be one important mechanism linking obstructive sleep apnea (OSA) with cardiovascular diseases. We tested the association between several hemostatic parameters and sleep breathing-related variables in a representative pediatric population with a clinical suspicion of OSA. MethodsPolysomnography was performed in 152 snoring children to diagnose OSA. Anthropometric and clinical data were registered and venous blood samples were collected for the measurement of platelet count, plateletcrit, platelet distribution width (PDW), mean platelet volume (MPV), prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen and C-reactive protein. ResultsChildren with OSA had significantly higher platelet count, plateletcrit and PDW compared with those without OSA. After controlling for the anthropometric characteristics (age, gender, body mass index (BMI) z-score), platelet count negatively correlated with minimum SaO2 while the plateletcrit correlated with time with SaO2 <90% and MPV correlated with apnea–hypopnea index. PT and PT international normalized ratio correlated with mean SaO2 and aPTT correlated with the oxygen desaturation index. ConclusionOur findings suggest that different OSA-related effects may be factors contributing to an enhanced coagulability in pediatric OSA. Measures reflecting apnea severity and disrupted sleep were associated with clotting factor changes independent of covariates affecting hemostatic function.

Idiopathic normal-pressure hydrocephalus and obstructive sleep apnea are frequently associated: A prospective cohort study

BackgroundIdiopathic normal-pressure hydrocephalus (iNPH) is defined by ventriculomegaly, cognitive decline, urinary incontinence and gait problems. Vascular risk factors (VRF) are associated with iNPH but obstructive sleep apnea (OSA) —a well-known independent VRF— is seldom mentioned. MethodsWe investigated the presence of sleep-disordered breathing in a prospective cohort of 31 consecutive unselected patients with iNPH using sleep questionnaires and nocturnal polysomnography (PSG). ResultsWe found OSA in 90·3% (28/31) patients with iNPH; all had undiagnosed sleep abnormalities (snoring, awakenings, nocturia) and excessive daytime sleepiness (Epworth scale = 11·4 ± 6·4; normal <8). Nocturnal PSG showed moderate-to-severe OSA in 25 patients (80·6%) with mean apnea-hypopnea index (AHI) 31·6 ± 23·6/h; mean respiratory distress index (RDI) 34·5/h; and, mean SaO2 desaturation at nadir, 82·2 ± 7·5%. The observed OSA prevalence is statistically significant: 90·3%, 95%CI 74·3–97·5; p = 0·000007. Other VRF included overweight body-mass index (BMI >25- < 30 kg/m2) in 59%, hyperhomocysteinemia 57%, hypertension 43%, hyperlipidemia 39%, diabetes 32%, smoking 21%, coronary disease 18%, and previous stroke 10%. ConclusionAbnormal sleep breathing is frequently associated with iNPH. Validation in larger series is required but we suggest including sleep evaluation in patients suspected of iNPH.

Efficacy and safety assessment of expiratory positive airway pressure (EPAP) mask for OSAHS therapy

ObjectiveWe have designed the expiratory positive airway pressure (EPAP) mask to provide a new sort of therapeutic strategies for Obstructive Sleep Apnea Hypopnea Syndrome (OSAHS). And this study aims to assess the safety, efficacy and compliance of the EPAP therapy. Methods40 healthy volunteers were enrolled to measure the end-tidal carbon dioxide pressure (PETCO2) while being treated by EPAP mask. 40 symptomatic moderate or severe OSAHS patients (AHI≥15/h) recruited were equally divided into two groups randomly and treated with CPAP or mask for a week respectively. After a week of washing out, the patients were applied with exchanged therapeutic methods for another week. The PSG was performed at the end of each week of treatment with device-on. ResultsThere were no significant differences of PETCO2 under different exhaled positive pressure level between CPAP, EPAP therapies and non-therapy for the healthy volunteers (P>0.05). After being treated, among the OSAHS patients in the two groups, the ESS scores and AHI decreased, and minimum SaO2 and mean SaO2 increased significantly (all P>0.05). There was no significant differences of the efficacy between EPAP and CPAP therapy. ConclusionsEPAP mask therapy was safe and reliable with significant efficacy for selected OSAHS patients. However, the compliance needs further improvement.

Does Scoliosis Affect Sleep Breathing?

Scoliosis, especially thoracic curves, causes poor pulmonary function. As a result, scoliosis may impair sleep breathing. The literature regarding the relationship between scoliosis and sleep breathing is sparse. Fifty-seven patients with adolescent idiopathic scoliosis or congenital scoliosis and 25 healthy control subjects were included. The wrist sleep monitors was used. Sleep breathing was evaluated with the following parameters: 1) Respiratory Disorders Index (pRDI), indicating mean respiratory events per hour of sleep including apnea, hypoxia, and respiratory effort-related arousal; 2) Apnea and Hypopnea Index (pAHI), expressing the number of apnea and hypopnea events per hour of sleep; and 3) mean and minimal oxygen saturation (Sao2) during sleep. No differences in age, sex distribution, and body mass index were found between the two groups. Patients with scoliosis had statistically significant higher pRDI (median, 10.10 vs. 8.65; P= 0.039) and pAHI (median, 1.60 vs. 0.72; P= 0.029) scores than the control group. The minimal SaO2 value in patients with scoliosis was lower (median, 93% vs. 94%, respectively; P= 0.005), whereas no difference was found in the mean SaO2 value during sleep. In patients with scoliosis, pAHI scores were higher when lying on the convex side of the thoracic curve compared with the concave side (2.34 vs. 2.28, respectively; P= 0.044), whereas no such difference was observed in the control group. Patients with scoliosis have more respiratory events of apnea and hypopnea during sleep than the control group. The minimal SaO2 value in patients with scoliosis is lower than the normal population. Sleeping on the convex side of the thoracic curve results in higher pAHI scores than on the concave side.

Increased Serum Cystatin C in Early Parkinson's Disease with Objective Sleep Disturbances.

Background:Sleep disturbance is one of the major non-motor symptoms which cause the disability of Parkinson's disease (PD) patients. Cystatin C (CysC) is a more sensitive biomarker than serum creatinine or estimated glomerular filtration rate. Previous studies have reported altered CysC levels in neurodegenerative disorders and sleep disorders. This study aimed to explore the correlations of serum CysC levels and objective sleep disturbances in early PD.Methods:We recruited 106 early PD patients and 146 age- and sex-matched controls. All participants underwent clinical investigation and video-polysomnography. Sleep parameters and serum levels of CysC were measured. Then, we investigated the relationships between CysC and clinical variables and objective sleep disturbances in early PD patients.Results:The mean serum level of CysC was significantly higher in patients with early PD (1.03 ± 0.19 mg/L) compared to controls (0.96 ± 0.15 mg/L, P = 0.009). There were significantly positive correlations between serum CysC levels and age (r = 0.334, P < 0.001), gender (r = 0.264, P = 0.013), and creatinine levels (r = 0.302, P = 0.018) in early PD patients. Increased serum CysC levels in early PD patients were significantly associated with higher apnea and hypopnea index (AHI) (r = 0.231, P = 0.017), especially hypopnea index (r = 0.333, P < 0.001). In early PD patients, elevated serum CysC levels were positively correlated with oxygen desaturation index (r = 0.223, P = 0.021), percentage of time spent at oxygen saturation (SaO2) <90% (r = 0.644, P < 0.001), arousal with respiratory event during sleep (r = 0.247, P = 0.013). On the contrary, the elevated serum CysC levels were negatively correlated with mean and minimal SaO2 (r = −0.323, −0.315, both P = 0.001) in PD patients.Conclusions:The level of serum CysC was higher in early PD patients. PD patients with elevated serum CysC levels had more respiratory events and more severe oxygen desaturation. Therefore, the serum CysC levels may predict the severities of sleep-disordered breathing problems in early PD patients.

Evaluation of Physiological Parameters in Response to Endurance Exercise of Zanskar Ponies Adapted to High Altitude of Ladakh Region

Zanskar pony, a native horse breed of Ladakh mainly used for transportation in Trans-Himalayan region of India, is well adapted to high altitude hypobaric hypoxia environment. Due to extreme conditions of the Ladakh region, better endurance of these ponies under hypoxic and extreme cold conditions is of utmost concern for their recruitment in Indian Army. In the present study, 12 young trained Zanskar ponies were evaluated during endurance exercise at an altitude of 3292 meter above mean sea level. The animals were subjected to carriage transport with 65-70Kg load or riding on a track of 5-6 Km. Physiological parameters &lt;em&gt;viz&lt;/em&gt;., pulse rate (PR), heart rate (HR), rectal temperature (RT), respiratory rate (RR) and oxygen saturation (SaO&lt;sub&gt;2&lt;/sub&gt;) were recorded in Zanskar ponies during pre-exercise (T&lt;sub&gt;0&lt;/sub&gt;), post- exercise (T&lt;sub&gt;1&lt;/sub&gt;) and post recovery (T&lt;sub&gt;2, &lt;/sub&gt;2 hours post resting) stages. Results showed marked increase in PR, HR, RR and RT post exercise time points. The mean values of PR increased from 49.83±4.62 to 73.67±21.54 per minute, HR from 48±13.60 to 75±15.82 beats/min, RR from 37.83±9.70 to 57.67±13.48 per min and RT from 99.62±0.34 101.04±0.53 °F from pre stress to post endurance stress. The mean SaO&lt;sub&gt;2 &lt;/sub&gt;level reduced significantly (88.58±6.75 at T&lt;sub&gt;0&lt;/sub&gt; versus 64.00±18.70 at T&lt;sub&gt;1&lt;/sub&gt; and 54.42±14.79 at T&lt;sub&gt;2&lt;/sub&gt;) post exercise. This indicated limited availability of arterial oxygen for tissues which could be vital factor for adverse change in some of physio-biochemical parameters. Though the trend of physiological response was similar for all the 12 animals, still variation at individual animal level was observed during endurance stress. In future, some of these physiological parameters along with biochemical and molecular parameters could be evaluated as potential biomarkers in selecting ponies with superior endurance trait specifically under hypoxic conditions.

Association between serum adipocyte fatty acid binding protein level and insulin resistance in patients with OSAS

Objective: To investigate the association between serum adipocyte fatty acid binding protein (A-FABP) level and insulin resistance in patients with obstructive sleep apnea syndromes (OSAS). Methods: Eighty patients with snoring were monitored by overnight polysomnography (PSG) from September 2015 to July 2017, and there were 59 males and 21 females, aged from 22 to 77 years old (mean age 47±14 years old). Based on the apnea-hypopnea index (AHI), these patients were divided into three groups: primary snoring group (AHI<5/h, n=19), mild-moderate OSAS groups (5/h≤AHI≤30/h, n=23) and severe OSAS groups (AHI>30/h, n=38). The levels of A-FABP, the fasting plasma glucose (FPG), fasting insulin (FINS) and insulin resistance index (IRI) were compared between the primary snoring group and OSAS patients with different severities, and the correlations between serum A-FABP and IRI as well as PSG parameters were further evaluated using partial correlation analysis. Results: Compared with the primary snoring group [(15.6±3.5) μg/L] and mild-moderate group [(17.4±4.3) μg/L], there was a significant increase of the serum A-FABP level in the severe OSAS group [(21.4±4.6) μg/L](P=0.001, P=0.025). Additionally, after adjustment for BMI and age, serum A-FABP level showed significant positive correlations with FINS and IRI (r=0.478, P<0.001; r=0.356, P=0.035); serum A-FABP level was positively correlated with AHI and the arterial oxygen saturation (SaO(2)) < 90% time ratio in night (TS90%) (r=0.251, P=0.041 and r=0.271, P=0.035). Nevertheless, serum A-FABP level showed significant negative correlation with the lowest SaO(2) and the mean SaO(2) (r=-0.244, P=0.038 and r=-0.280, P=0.018). Conclusion: Insulin resistance and the increased level of serum A-FABP are common in OSAS patients, the level of serum A-FABP is significantly correlated with insulin resistance and nocturnal intermittent hypoxia, both of which suggest that A-FABP plays a potential role in insulin resistance in patients with OSAS.