Effects of Hypoxia on Selected Psychophysiological Stress Responses of Military Aircrew

There is a lack of information on the psychophysiological response of pilots under hypoxic conditions. The study of the physiological, psychological, cardiorespiratory, neurological, behavioural, sensory, and cognitive symptoms that may appear during training in hypobaric chambers is essential to optimize the training processes of aircrew members. Thus, the present study is aimed at analyzing the psychophysiological responses of aircrew members in an incremental hypoxia training protocol. Psychophysiological responses of 44 aircrew members (34 males and 10 females) in an incremental hypoxia training protocol (3 minutes at 0 meters, 8 minutes at 5,000 meters, and maximum time at 7500 meters) were measured. Results suggested that the incremental hypoxia training protocol did not affect cortical arousal and handgrip strength; however, it increased the sympathetic tone, perceived stress, perceived effort, and heart rate and decreased forced expiratory volume and blood oxygen saturation. Thus, we concluded that acute hypoxic hypobaric exposure leads to decreased parasympathetic tone, blood oxygen saturation, and maximal spirometry values, without negatively affecting handgrip strength and cortical arousal. This information will lead to find specific training systems that meet the real needs of aircrew.

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Long-term prognosis of the course of sarcoidosis: analysis of the literature and own experience

Kazan medical journal ◽

10.17816/kmj2280 ◽

2012 ◽

Vol 93 (2) ◽

pp. 167-172

Author(s):

I Yu Vizel

Keyword(s):

Oxygen Saturation ◽

Forced Expiratory Volume ◽

Acute Onset ◽

Blood Oxygen ◽

Blood Oxygen Saturation ◽

Lung Capacity ◽

Volume Rate ◽

Long Term Prognosis ◽

Chronic Course

Aim. To evaluate the prognosis of the course of sarcoidosis in patients with a follow-up term of 10 years or more. Methods. Analysis of the literature, comparison with the data from own research. Analyzed was the data on 15 patients with sarcoidosis with the follow-up term of 10 years or more. Compared were the parameters of spirometry, blood tests, blood oxygen saturation, of the conducted treatment in the patients with remission and with a chronic course. Results. In 8 patients (53.3%) during the last follow-up visit (10 years or more after detection) noted was a stable remission (in 7 after the initial detection and in 1 after a single exacerbation). Among all the 15 patients after 10 years or more the frequency of dyspnea on exertion increased from 33.3 to 46.9%, chest pain - from 6.7 to 20%, complaints of weakness decreased from 66.7 to 53.3%, of fever - from 26.7 to 13.3%, and of cough - from 53.3 to 20%, of erythema nodosum - from 40 to 6.7%, of articular syndrome - from 60 to 20%, of splenomegaly - from 13.3 to 6.7%. When comparing the dynamics of the indicators in the subgroup with persistent remission noted was a significant decrease in the instantaneous volume rate after the exhalation of 50% of the forced vital lung capacity; blood oxygen saturation and diastolic blood pressure significantly increased, the proportion of monocytes in the leukocyte formula decreased. Registered was a significant increase in erythrocyte sedimentation rate within the physiological range. In patients with a chronic course of sarcoidosis occurred a significantly reduction of the forced vital lung capacity, of the forced expiratory volume in 1 s, of the instantaneous volume rate after exhalation of 25% of the forced vital lung capacity. Conclusion. The best prognosis had the patients, who were young adults with an acute onset, and who did not receive glucocorticoids. Pentoxifylline may improve the course and outcome of sarcoidosis.

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The Application of Different Breathing Training Methods in Elderly Patients With Femoral Neck Fracture: A Prospective, Randomized, and Single-Blind Study

10.21203/rs.3.rs-958980/v1 ◽

2021 ◽

Author(s):

Yan Zhang ◽

Hong Wang ◽

Mei Jing Fan ◽

Lin Fan ◽

Min Wang

Keyword(s):

Lung Function ◽

Femoral Neck ◽

Elderly Patients ◽

Oxygen Saturation ◽

Forced Expiratory Volume ◽

Pulmonary Complications ◽

Femoral Neck Fractures ◽

Conventional Group ◽

Blood Oxygen ◽

Blood Oxygen Saturation

Abstract Purpose: Femoral neck fractures in elderly patients lead to reduced mobility and increased risk of pulmonary complications. The main purpose of this study is to observe the forced expiratory volume in the first second(FEV1), forced vital capacity(FVC), blood oxygen saturation(SPO2), pulmonary complications, and hospitalization days in elderly patients with femoral neck fractures, and to evaluate the use of lung function trainers to train elderly patients’ lung function effect and feasibility.Methods: This is a prospective, randomized and single-blind study. 108 elderly patients with femoral neck fractures over 70 years old were randomly divided into a conventional group and a lung function trainer group. The conventional group received effective cough training and lip-reducing breathing training, and the lung function trainer group received effective cough training and lung function training. Until 2 weeks after surgery. The main outcomes are forced expiratory volume in the first second, forced vital capacity, and blood oxygen saturation. The secondary outcomes are pulmonary complications and the hospitalization days.Results: 50 subjects in the conventional group and 51 subjects in the lung function trainer group completed the study. On the 3rd and 7th day of training, the FVC of the lung function trainer group was higher than that of the conventional group (2.94±0.40vs.2.72±0.34,P<0.05；3.02±0.40vs.2.86±0.34,P<0.05), and the FVE1 of the the lung function trainer group was higher than that of the conventional group (1.99±0.37vs.1.80±0.42，P＜0.05；2.14±0.39vs.1.94±0.43,＜0.05), and the blood oxygen saturation of the lung function trainer group was higher than that of the conventional group ( 97.10±1.35vs.96.28±1.21；97.47±1.35vs.96.86±1.36,P＜0.05), 4 cases of pneumonia in the conventional group, no one in the lung function trainer group was diagnosed with pneumonia, and the hospitalization days in the lung function trainer group was less than that in the conventional group (15.55±1.45VS.17.2±2.58,P<0.05).Conclusion: For elderly patients with femoral neck fracture, the use of lung function training device to strengthen respiratory muscle function training during perioperative period can improve the patient's lung function in a short period of time, reduce the complications of respiratory system infection, and shorten the hospitalization days. It is worthy of clinical application.

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The Influence of High-Altitude Acclimatization on Ventilatory and Blood Oxygen Saturation Responses During Normoxic and Hypoxic Testing

Journal of Human Kinetics ◽

10.1515/hukin-2015-0149 ◽

2016 ◽

Vol 50 (1) ◽

pp. 125-133 ◽

Cited By ~ 1

Author(s):

Anton Ušaj ◽

Stojan Burnik

Keyword(s):

Oxygen Saturation ◽

High Altitude ◽

Ventilatory Threshold ◽

Body Height ◽

Endurance Performance ◽

Cycle Ergometer ◽

Blood Oxygen ◽

Blood Oxygen Saturation ◽

Hypoxic Conditions ◽

High Altitude Acclimatization

AbstractWe investigated how acclimatization effects achieved during a high-altitude alpinist expedition influence endurance performance, ventilation (${\dot V_E}$) and blood oxygen saturation (SaO2) in normoxic (NOR) and hypoxic conditions (HYP). An incremental testing protocol on a cycle ergometer was used to determine the power output corresponding to the Lactate (PLT) and Ventilatory Threshold (PVT) in NOR and HYP (FiO2=0.13) as indirect characteristics of endurance performance in both conditions. Furthermore, changes in ${\dot V_E}$, SaO2, blood pH and Pco2 were measured at a similar absolute exercise intensity of 180 W in NOR and HYP conditions. Seven experienced alpinists (mean ± SD: age: 50 ± 6 yrs; body mass: 76 ± 5 kg; body height: 175 ± 8 cm) volunteered to participate in this study after they had reached the summit of Gasherbrum II and Ama Dablam. They had therefore experienced the limitations of their acclimatization. Individual differences of PLT between values reached after and before the expedition (∆PLT) correlated (r = 0.98, p = 0.01) with differences of SaO2 (∆SaO2) in HYP, and differences of PVT (∆PVT) correlated (r = -0.83, p = 0.02) with differences of ${\dot V_E}\left( {\Delta {{\dot V}_E}} \right)$ in HYP. The results suggest that the acclimatization may not have an equivocal and simple influence on the performance in hypoxia: enhanced blood oxygen saturation may be accompanied by increased endurance only, when the increase exceeded 2-3%, but enhanced ventilation, when increased more than 10 l/min in HYP, could detrimentally influence endurance.

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PSIX-9 Impacts of bunk management on feedlot performance, carcass characteristics, hydrogen sulfide concentration and blood oxygen saturation in steers fed 25 or 50% modified distillers grains plus solubles

Journal of Animal Science ◽

10.1093/jas/skaa278.735 ◽

2020 ◽

Vol 98 (Supplement_4) ◽

pp. 422-422

Author(s):

Rebecca L Moore ◽

Cierrah J Kassetas ◽

Leslie A LeKatz ◽

Bryan W Neville

Keyword(s):

Hydrogen Sulfide ◽

Oxygen Saturation ◽

Management Strategy ◽

Distillers Grains ◽

Feed Ratio ◽

Sulfide Concentration ◽

Blood Oxygen ◽

Blood Oxygen Saturation ◽

Feedlot Performance ◽

Arterial Blood

Abstract One hundred and twenty-six yearling angus steers (initial body weight 445.87 ± 7.13 kg) were utilized in a 2 x 2 factorial design to evaluate the impacts of bunk management and modified distillers grains plus solubles (mDGS) inclusion on feedlot performance, hydrogen sulfide concentrations and blood oxygen saturation. Treatments included bunk management strategy either control bunk management (CON; clean bunks at the time of next day’s feeding) or long bunk management (LONG; feed remaining at time of next day’s feeding), and two inclusion rates of mDGS either 25% or 50% (DM Basis). On d 0, 7, 14, 21, 28 and 35 rumen gas samples were collected via rumenocentesis, and arterial blood samples were collected on two steers from each pen. No differences (P ≥ 0.09) were observed for dry matter intake, average daily gain and gain-to-feed ratio for bunk management or mDGS inclusion. Hot carcass weight, ribeye area, marbling score and quality grade were not affected (P ≥ 0.48) by either bunk management or mDGS inclusion. Back fat was greater (P = 0.04) for CON steers compared to LONG (1.30 vs 1.12 ± 0.05cm, respectively), but was not affected (P = 0.59) by mDGS inclusion. Steers on CON had greater (P = 0.03) yield grades compared to LONG (3.21 vs 2.96 ± 0.11, respectively). Bunk management strategy did not impact hydrogen sulfide concentrations or blood oxygen saturation (P = 0.82). Hydrogen sulfide concentrations increased (P < 0.001) with increasing mDGS inclusion. Blood oxygen saturation was influenced by day of sampling (P = 0.01). Blood oxygen saturation was not affected (P = 0.07) by mDGS inclusion. The fact that ruminal hydrogen sulfide concentrations increased while blood oxygen saturation remained similar raises questions about the quantity of hydrogen sulfide and metabolic fate of excess hydrogen sulfide in the blood of ruminant animals.

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Accurate Detection of Heart Rate and Blood Oxygen Saturation in Reflective Photoplethysmography

2020 IEEE International Symposium on Signal Processing and Information Technology (ISSPIT) ◽

10.1109/isspit51521.2020.9408845 ◽

2020 ◽

Author(s):

Maria Krizea ◽

John Gialelis ◽

Anastasios Kladas ◽

Gerasimos Theodorou ◽

Grigoris Protopsaltis ◽

...

Keyword(s):

Heart Rate ◽

Oxygen Saturation ◽

Blood Oxygen ◽

Blood Oxygen Saturation ◽

Accurate Detection

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Remote, in-vivo monitoring of blood oxygen saturation of patients using optical fibres

Conference on Lasers and Electro-Optics Europe ◽

10.1109/cleoe.1994.636470 ◽

2005 ◽

Cited By ~ 1

Author(s):

P.J. Scully ◽

R. Holmes ◽

G.R. Jones

Keyword(s):

Oxygen Saturation ◽

Optical Fibres ◽

Blood Oxygen ◽

Blood Oxygen Saturation ◽

In Vivo Monitoring

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Pulse Oximetry and Breathing Training1

Biofeedback ◽

10.5298/1081-5937-40.4.04 ◽

2012 ◽

Vol 40 (4) ◽

pp. 137-141 ◽

Cited By ~ 3

Author(s):

Christopher Gilbert

Keyword(s):

Oxygen Saturation ◽

Pulse Oximetry ◽

Medical Condition ◽

Noninvasive Monitoring ◽

Control Of Breathing ◽

Oxygen Absorption ◽

Blood Oxygen ◽

Blood Oxygen Saturation ◽

Training Control ◽

Pulse Oximeters

Small pulse oximeters have become widely available and can be useful for noninvasive monitoring of blood oxygen saturation by nonmedical personnel. When training control of breathing, an oximeter helps to reassure clients who hyperventilate that their oxygenation is adequate, offsetting their perception that they are not getting enough air. Low saturation may indicate a medical condition that impairs oxygen absorption. In that case, hyperventilation is a biological compensation that should not be tampered with.

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Blood Oxygen Saturation Measurement Using Polarization-Dependent Optical Sectioning

IEEE Sensors Journal ◽

10.1109/jsen.2017.2698520 ◽

2017 ◽

Vol 17 (12) ◽

pp. 3900-3908 ◽

Cited By ~ 7

Author(s):

Deepak Mishra ◽

Neha Priyadarshini ◽

Supriya Chakraborty ◽

Mukul Sarkar

Keyword(s):

Oxygen Saturation ◽

Blood Oxygen ◽

Optical Sectioning ◽

Blood Oxygen Saturation ◽

Saturation Measurement

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Optical Measurement of Blood Oxygen Saturation of Dental Pulp

ISRN Biomedical Engineering ◽

10.1155/2013/502869 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

Satoko Kakino ◽

Shinya Kushibiki ◽

Azusa Yamada ◽

Zenzo Miwa ◽

Yuzo Takagi ◽

...

Keyword(s):

Light Intensity ◽

Oxygen Saturation ◽

Dental Pulp ◽

Optical Measurement ◽

Blood Oxygen ◽

Arterial Pulse ◽

Blood Oxygen Saturation ◽

Visible Wavelengths

The applicability of arterial pulse oximetry to dental pulp was demonstrated using in vitro and in vivo measurements. First, porcine blood of known oxygen saturation (SO2) was circulated through extracted human upper incisors, while transmitted-light plethysmography was performed using three different visible wavelengths. From the light intensity waveforms measured in vitro, a parameter that is statistically correlated to SO2 was calculated using the pulsatile/nonpulsatile component ratios of two wavelengths for different SO2. Then, values were measured in vivo for living incisors, and the corresponding SO2 values were calculated using the results of in vitro measurements. The estimated SO2 values of the upper central incisors measured in vivo were from 71.0 to 92.7%. This study showed the potential to measure the oxygen saturation changes to identify the sign of pulpal inflammation.

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