Symptoms Of Hypoxia Research Articles

Hypoxia and Time of Useful Consciousness in Hypobaric Chamber at 25,000 feet in Aircrew at dr. Saryanto Health Institute of Aeronautics and Space

Introduction: Hypoxia is a condition characterized by insufficient oxygen supply to tissues which causes body tissues to fail to get adequate oxygen supply. Hypobaric hypoxia is generally recognized as the most serious physiological hazard during high-altitude flight. This puts active crew members at risk for hypoxia and so they rely on effective performance time (EPT) or time useful consciousness (TUC) to take appropriate corrective and protective actions when hypoxia occurs. This study aimed to describe TUC scores and hypoxia symptoms experienced by active flight crew at dr. Saryanto Health Institute of Aeronautics and Space in 2021. Methods: A descriptive research design using medical record data from 99 flight crew with simple random sampling. The variables in this study consisted of hypoxia symptoms and TUC scores. This study uses univariate analysis to see the frequency distribution of the variables of hypoxia symptoms and TUC score. Results: The results showed that 18.2% experienced cognitive symptoms, 4% experienced psychomotor symptoms, 16.2% experienced visual symptoms, 3% experienced psychological symptoms, 54.5% experienced non-spesific symptoms, and 37.4% did not feel any symptoms. Most of the flight crew (68.7%) had sufficient EPT/TUC scores (3-4 minutes). Conclusion: Active flight crews feel symptoms of hypoxia and have sufficient TUC scores.

Anoxic Brain Injury: A Subtle and Often Overlooked Finding in Non-Fatal Intimate Partner Strangulation

BackgroundA paucity of literature exists dedicated to the identification of anoxic brain injury in patients that survive non-fatal intimate partner strangulation (NF-IPS). While some individuals report experiencing symptoms of brain hypoxia followed by a loss of consciousness, other individuals report symptoms of brain hypoxia prior to amnesia, rendering some unable to recall loss of consciousness (LOC). ObjectiveUsing a standardized clinical assessment tool, the purpose of this retrospective analysis is to describe anoxic brain injury symptom prevalence in a sample of patients reporting NF-IPS. MethodsOne hundred and ninety-one unique patients, reporting a total of 267 strangulation events, were assessed by a member of the Shasta Community Forensic Care Team utilizing the Strangulation Hypoxia Anoxia Symptom TBI Assessment (SHASTA) tool. The sample is 98% female and includes adult patients ages 18–68. Examination records were categorized based on the presence or absence of hypoxia and anoxia symptoms. This manuscript utilizes the STROBE checklist. ResultsAmnesia was reported in 145 of the 267 strangulations (54.3%). Of those, 74 reported LOC (51.0%) while 71 did not recall LOC (49.0%). ConclusionsWithin our sample, 49% of patients with amnesia did not recall losing consciousness, demonstrating that LOC is an imperfect measure of anoxia for patients following NF-IPS. Healthcare providers examining NF-IPS patients should inquire about additional symptoms of hypoxia and amnesia, which can be captured on the SHASTA tool.

Network pharmacology analysis and clinical efficacy of the traditional Chinese medicine Bu-Shen-Jian-Pi. Part2: Modulation of hypoxia, redox status, and mitochondrial protection ina neuroblastoma cell line, SH-SY5Y.

To examine the mitochondrial protective effects of icariin, naringenin, kaempferol, and formononetin, potentially active agents in Bu-Shen-Jian-Pi formula (BSJP) identified using network pharmacology analysis. Mitochondrial protection activity was determined using a hypoxia-reoxygenation in vitro model based on the neuroblastoma cell line SH-SY5Y and measurements of anti-ferroptotic activity. Icariin, naringenin, kaempferol, and formononetin showed mitochondrial protective activity involving diverse signaling pathways. The cytoprotective effects of formononetin depended on the inhibition of ferroptosis. Hypoxia-reoxygenation stimulation induced ferroptosis in SH-SY5Y cells. Ferroptosis is a key mechanism in nervous system diseases and is associated with hypoxia-reoxygenation injury. Naringenin and kaempferol were devoid of anti-ferroptotic activity. Evidence has been obtained showing that the core components: icariin, naringenin, kaempferol, and formononetin in BSJP formula have anti-hypoxic and mitochondrial protective activity of potential clinical importance in the treatment of amyotrophic lateral sclerosis and patients with symptoms of hypoxia.

Lessons Learned from the Lived Experiences of COVID-19 ICU Survivors Who are Struggling Through Critical Conditions and Surviving to Champion Life: A Qualitative Study.

Due to the coronavirus disease 2019 (COVID-19) pandemic, millions of lives were lost globally, including in Indonesia. Some patients with COVID-19 may experience severe symptoms of hypoxia, while some may be critically ill and admitted to the intensive care unit (ICU) for survival. This study aimed to understand the lived experiences of COVID-19 ICU survivors who were in a critical condition. This phenomenological study used semistructured interviews with nine participants who were COVID-19 ICU survivors. Data analysis was performed using the Colaizzi approach. The phenomenon of the lived experiences of COVID-19 ICU survivors was presented in seven subthemes and four main themes: struggling in a state of helplessness, fostering a positive spirit from within, amplifying the support from nurses and doctors, and strengthening the connection with family andthe Almighty. These themes indicated the essential aspects of psychosocial support needed to boost strength and energy and elevate the body's immune system, which is crucial to champion life through critical conditions. The new insight resulting from the study is shown in the four main themes, which play a significant role in elevating the healing process and enabling patients to survive critical conditions. Therefore, this study recommends the importance of psychosocial support for patients with critical conditions, which involves family and their significant others, and facilitating the connection between the patient and God.

Comparing neuronal oscillations during visual spatial attention orienting between normobaric and hypobaric hypoxia

Normobaric hypoxia (NH) and hypobaric hypoxia (HH) are both used to train aircraft pilots to recognize symptoms of hypoxia. NH (low oxygen concentration) training is often preferred because it is more cost effective, simpler, and safer than HH. It is unclear, however, whether NH is neurophysiologically equivalent to HH (high altitude). Previous studies have shown that neural oscillations, particularly those in the alpha band (8–12 Hz), are impacted by hypoxia. Attention tasks have been shown to reliably modulate alpha oscillations, although the neurophysiological impacts of hypoxia during cognitive processing remains poorly understood. To address this we investigated induced and evoked power alongside physiological data while participants performed an attention task during control (normobaric normoxia or NN), NH (fraction of inspired oxygen = 12.8%, partial pressure of inspired oxygen = 87.2 mmHg), and HH (3962 m, partial pressure of inspired oxygen = 87.2 mmHg) conditions inside a hypobaric chamber. No significant differences between NH and HH were found in oxygen saturation, end tidal gases, breathing rate, middle cerebral artery velocity and blood pressure. Induced alpha power was significantly decreased in NH and HH when compared to NN. Participants in the HH condition showed significantly increased induced lower-beta power and evoked higher-beta power, compared with the NH and NN conditions, indicating that NH and HH differ in their impact on neurophysiological activity supporting cognition. NH and HH were found not to be neurophysiologically equivalent as electroencephalography was able to differentiate NH from HH.

Value of brain injury-related indicators based on neural network in the diagnosis of neonatal hypoxic-ischemic encephalopathy.

Neonatal hypoxic ischemic encephalopathy is a common disease, which is caused by fetal hypoxia, asphyxia, and other reasons. It may cause sequelae of the nervous system and even death in children. Computer tomography examination can clarify the scope and location of the disease and provide the basis for clinical treatment and prognosis. Relevant personnel analyzed the symptoms of ischemic hypoxia and found that ischemia and hypoxia were the main causes of encephalopathy. Neonatal ischemia and hypoxia are easy to cause serious damage. At present, with the development of medicine, the function of the human brain is the most important issue in natural science. The law of neural activity and the role of molecular cells, organs, and systems have fundamental construction significance for the prevention and treatment of nerve and mental diseases. By analyzing the value of the diagnosis of neonatal hypoxic-ischemic encephalopathy in the analysis of experimental data, by setting the newborns in the controlled group and the trial group as experimental subjects, this paper analyzed the situation of newborns in terms of body temperature, body weight, and respiratory rate, and used Apgar score to score these standards. It was found that the score of the controlled group was 7 and above, and the score of the trial group was below 7. It was found that the Apgar scoring method was more simple. Then, the newborns were analyzed by cord blood gas analysis. It was found that most of the data in the control group were between 7.8 and 8.4, and the data in the trial group were between 5.8 and 7.1. The umbilical blood gas analysis score of the experimental group was lower than that of the control group. By comparing the satisfaction of cord blood gas analysis and the Apgar score, it was found that the satisfaction of cord blood gas analysis was 24.06% higher than that of the Apgar score.

Eutrophication assessment and environmental management perspectives of Tóbari: an arid subtropical coastal lagoon of the Gulf of California.

Coastal lagoons are vulnerable to eutrophication processes. In this study, we evaluate the eutrophication process in the restricted, arid subtropical Tóbari coastal lagoon, located in the eastern coast of the Gulf of California, where the main source of nutrient inputs and other pollutants is agricultural wastewater from the Yaqui Valley. The Assessment of Estuarine Trophic Status (ASSETS) model and the Trophic State Index (TRIX) were used to evaluate eutrophication. Overall, ASSETS showed that the Tóbari lagoon has a moderate eutrophication process, with seasonal symptoms of hypoxia, increased phytoplankton biomass, dominance of macroalgae (indicative of nutrient enrichment), and blooms development of potentially harmful algae species. The TRIX showed that the lagoon is mesotrophic most of the year. Challenges of environmental management detected correspond to reducing the input of nutrients and others contaminants from anthropic sources: agriculture, shrimp farming, livestock, and urban zones.

Neonatal gastric perforation: Case report

Neonatal gastric perforation (NGP) is a life-threatening condition associated with high morbidity and mortality rates. Despite several proposed etiological theories, the causative principle is still unclear and controversial. A male neonate was born at 26 weeks 3 days gestation. The patient showed symptoms of acute respiratory failure and hypoxia and was admitted to the neonatal intensive care unit. On day of life (DOL) 2, a chest and abdominal radiography showed a large amount of free intraperitoneal air, for which exploratory laparotomy was performed. A small antimesenteric perforation in the distal ileum was found and repaired primarily. On DOL 7, a chest and abdominal radiography demonstrated recurrent pneumoperitoneum for which a repeat exploratory laparotomy was performed. The patient had global intestinal ischemia and a perforation in the anterior wall of the stomach, which was repaired. On DOL 12, a planned upper gastrointestinal water-soluble contrast study showed spillage of contrast into the anterior abdomen, for which the patient underwent a repeat exploratory laparotomy. We found a dehiscence of the prior gastric repair and closed it primarily. The remainder of the hospital course was uneventful and the patient reached full feedings on DOL 41. Premature neonates are at risk for gastric perforation. Gastric perforation should be in the differential diagnosis of a premature neonate who presents abdominal distension and pneumoperitoneum. Due to the fragility of the premature neonatal tissues, confirming the integrity of the gastric closure with a contrast study is recommended prior to initiating enteral feedings.

Combined altitude depleted oxygen vis-à-vis hypobaric hypoxia: Efficacy in hypoxia indoctrination

Introduction: The Combined Altitude and Depleted Oxygen (CADO), as an alternate method for hypoxia indoctrination, has the dual advantages of exposing to an altitude less than the threshold for decompression sickness, a known risk in training using Hypobaric Hypoxia (HH) while accounting for the pressure changes due to altitude, a limitation of using normobaric hypoxia. Objectives: This study aimed to evaluate the efficacy of CADO in hypoxia indoctrination by comparing it with the time-tested gold standard method of HH. Material and Methods: Forty subjects were exposed to both CADO and HH, simulating 25,000 ft for a maximum period of 5 min. CADO was achieved by combining exposure to an altitude of 10,000 ft in the hypobaric chamber and breathing a hypoxic gas mixture of 10.3% oxygen and 89.7% nitrogen. Physiological parameters (oxygen saturation, heart rate, and respiratory rate) and psychomotor performance (dual task test component of pSuMEDhA) were compared between the two exposures. The incidence and severity of subjective symptoms were also compared at the end of exposures. Results: No significant difference was observed in the physiological parameters and psychomotor performance during the two exposures. Out of the 24 common symptoms of hypoxia assessed, there was a higher incidence of 20 symptoms in subjects exposed to HH compared to CADO. The severity of 15 symptoms was also found to be significantly greater (P < 0.05) in subjects exposed to HH. Conclusion: The similarity of physiological changes in CADO and HH shows the potential application of CADO as a tool for hypoxia demonstration. However, in view of decreased incidence and severity of subjective symptoms in CADO compared to HH, CADO cannot be considered equivalent to the gold standard (HH) for hypoxia indoctrination for high-risk individuals, namely, aircrew and combat free fall personnel. CADO as a modality can be used as a tool for hypoxia demonstration for persons not involved in flying duties and for high-altitude research.

Integrating UPLC-Q-Exactive Orbitrap/MS, network pharmacology and experimental validation to reveal the potential mechanism of Tibetan medicine Rhodiola granules in improving myocardial ischemia-reperfusion injury

Ethnopharmacology relevanceRhodiola granules (RG) is a traditional Tibetan medicine prescription that can be used to improve the symptoms of ischemia and hypoxia in cardiovascular and cerebrovascular diseases. However, there is no report on its use to improve myocardial ischemia/reperfusion (I/R) injury, and its potential active ingredients and mechanism against myocardial ischemia/reperfusion (I/R) injury remain unclear. Aim of the studyThis study aimed to reveal the potential bioactive components and underlying pharmacological mechanisms of RG in improving myocardial I/R injury through a comprehensive strategy. Materials and methodsUPLC-Q-Exactive Orbitrap/MS technology was used to analyze the chemical components of RG, the potential bioactive components and targets were tracked and predicted by the SwissADME and SwissTargetPrediction databases, and the core targets were predicted through the PPI network, as well the functions and pathways were determined by GO and KEGG analysis. In addition, the molecular docking and ligation of the anterior descending coronary artery-induced rat I/R models were experimentally validated. ResultsA total of 37 ingredients were detected from RG, including nine flavones, ten flavonoid glycosides, one glycoside, eight organic acids, four amides, two nucleosides, one amino acid, and two other components. Among them, 15 chemical components, such as salidroside, morin, diosmetin, and gallic acid were identified as key active compounds. Ten core targets, including AKT1, VEGF, PTGS2, and STAT3, were discovered through the analysis of the PPI network constructed from 124 common potential targets. These possible targets were involved in the regulation of oxidative stress and HIF-1/VEGF/PI3K-Akt signaling pathways. Furthermore, molecular docking confirmed that the potential bioactive compounds in RG have good potential binding abilities to AKT1, VEGFA, PTGS2, STAT3, and HIF-1α proteins. Then, the animal experiments showed that RG could significantly improve the cardiac function of I/R rats, reduce the size of myocardial infarction, improve the myocardial structure, and reduce the degree of myocardial fibrosis, inflammatory cell infiltration, and myocardial cell apoptosis rate in I/R rats. In addition, we also found that RG could decrease the concentration of AGE, Ox-LDL, MDA, MPO, XOD, SDH, Ca2+, and ROS, and increase the concentration of Trx, TrxR1, SOD, T-AOC, NO, ATP, Na+k+-ATPase, Ca2+-ATPase, and CCO. Moreover, RG could significantly down-regulate the expressions of Bax, Cleaved-caspase3, HIF-1α, and PTGS2, as well up-regulate the expressions of Bcl-2, VEGFA, p-AKT1, and p-STAT3. ConclusionIn summary, we revealed for the first time the potential active ingredients and mechanisms of RG for myocardial I/R injury therapy through a comprehensive research strategy. RG may synergistically improve myocardial I/R injury through anti-inflammatory, regulating energy metabolism, and oxidative stress, improving I/R-induced myocardial apoptosis, which may be related to the HIF-1/VEGF/PI3K-Akt signaling pathway. Our study provides new insights into the clinical application of RG and also provides a reference for the development and mechanism research of other Tibetan medicine compound preparations.

Nursing Intervention in Handling Covid-19 Hypoxia Patients in the Isolation Room of Covid-19 Hospital Badaruddin Kasim Tanjung South Kalimantan

Coronavirus 2019 (Covid-19) is an infectious disease caused by the acute respiratory syndrome of coronavirus 2 (Sars-CoV-2). Some complaints appear in patients who are confirmed to be covid-19, one of which is hypoxia, hypoxia is a condition of low levels of O2 contained in cells / tissues to below the physiological level. Nursing intervention activities against clients with hypoxia that nurses must do is to adjust the position of the client's body to reduce lung workload, teach correct breathing techniques, pay attention to the environment, collaboration on O2 administration. The research aims to find out nursing interventions in handling Covid-19 hypoxia patients in the Covid-19 Isolation Room of H. Badaruddin Kasim Tanjung Hospital. This study used qualitative methods with interview techniques that explained the implementation of nursing interventions with hypoxia clients with COVID-19 in the Isolation Room of Badaruddin Kasim Tanjung Hospital. Sampling using purposive sampling techniques. Data is analyzed through the results of interview recordings in the form of verbatim transcripts or descriptions of recordings in the form of written descriptions or narative texts. based on the results of the interview produced 6 sub themes, namely changing the position of semifowler patients in maximizing breathing, oxygen administration, monitor respiration status, observation of the respiratory department, monitor symptoms of hypoxia & happy hypoxia, and airway monitor.

Noninvasive Brain Stimulation for Neurorehabilitation in Post-Stroke Patients.

Characterized by high morbidity, mortality, and disability, stroke usually causes symptoms of cerebral hypoxia due to a sudden blockage or rupture of brain vessels, and it seriously threatens human life and health. Rehabilitation is the essential treatment for post-stroke patients suffering from functional impairments, through which hemiparesis, aphasia, dysphagia, unilateral neglect, depression, and cognitive dysfunction can be restored to various degrees. Noninvasive brain stimulation (NIBS) is a popular neuromodulatory technology of rehabilitation focusing on the local cerebral cortex, which can improve clinical functions by regulating the excitability of corresponding neurons. Increasing evidence has been obtained from the clinical application of NIBS, especially repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS). However, without a standardized protocol, existing studies on NIBS show a wide variation in terms of stimulation site, frequency, intensity, dosage, and other parameters. Its application for neurorehabilitation in post-stroke patients is still limited. With advances in neuronavigation technologies, functional near-infrared spectroscopy, and functional MRI, specific brain regions can be precisely located for stimulation. On the basis of our further understanding on neural circuits, neuromodulation in post-stroke rehabilitation has also evolved from single-target stimulation to co-stimulation of two or more targets, even circuits and the network. The present study aims to review the findings of current research, discuss future directions of NIBS application, and finally promote the use of NIBS in post-stroke rehabilitation.

L'ossigenoterapia

Oxygen supplementation represents a fundamental therapy in several clinical conditions, both acute and chronic. Starting from some concepts of respiratory physiopathology, this paper discusses the approach to a child with respiratory distress and respiratory failure, focuses on the main signs and symptoms of hypoxia, hypercapnia and increased work of breathing and explains the methods to assess the severity of the clinical status, highlighting the relevance of the SpO2/FiO2 ratio (peripheral oxygen saturation/inspiratory oxygen fraction). Furthermore, this work aims to summarize the main methods of oxygen delivery, their relative indications, by underlining advantages and possible complications such as blow-by oxygen, low flow nasal cannula and face mask (simple, Venturi, rebreathing and non-rebreathing). The focus is on two new oxygen delivery devices, High Flow Nasal Cannula (HFNC) and Continuous Positive Airway Pressure (CPAP), which in recent years have more and more been used not only in emergency units but also in paediatric wards.

Associations between spontaneous electroencephalogram oscillations and oxygen saturation across normobaric and hypobaric hypoxia.

High-altitude indoctrination (HAI) trains individuals to recognize symptoms of hypoxia by simulating high-altitude conditions using normobaric (NH) or hypobaric (HH) hypoxia. Previous studies suggest that despite equivalent inspired oxygen levels, physiological differences could exist between these conditions. In particular, differences in neurophysiological responses to these conditions are not clear. Our study aimed to investigate correlations between oxygen saturation (SpO2 ) and neural responses in NH and HH. We recorded 5-min of resting-state eyes-open electroencephalogram (EEG) and SpO2 during control, NH, and HH conditions from 13 participants. We applied a multivariate framework to characterize correlations between SpO2 and EEG measures (spectral power and multiscale entropy [MSE]), within each participant and at the group level. Participants were desaturating during the first 150 s of NH versus steadily desaturated in HH. We considered the entire time interval, first and second half intervals, separately. All the conditions were characterized by statistically significant participant-specific patterns of EEG-SpO2 correlations. However, at the group level, the desaturation period expressed a robust pattern of these correlations across frequencies and brain locations. Specifically, the first 150 s of NH during desaturation differed significantly from the other conditions with negative absolute alpha power-SpO2 correlations and positive MSE-SpO2 correlations. Once steadily desaturated, NH and HH had no significant differences in EEG-SpO2 correlations. Our findings indicate that the desaturating phase of hypoxia is a critical period in HAI courses, which would require developing strategies for mitigating the hypoxic stimulus in a real-world situation.

A Case of Thromboembolism and Deep Venous Thrombosis after Transfemoral Amputation with Short Stump

An 82-year-old patient underwent a left transfemoral amputation due to a malignant soft tissue tumor. He developed symptoms of chest pain and hypoxia on the 32nd day after the operation. These symptoms were caused by deep venous thrombosis (DVT) of the stump and acute pulmonary thromboembolism (PTE), for which he was treated with anticoagulant therapy. Shortly after treatment he could resume a rehabilitation therapy. Patients with a lower extremity amputation have a higher risk of developing a DVT because of immobility and increased venous pooling in the residual limb. Even with a short stump as in this case, it is important to actively train the range of motion of the joint and try to prevent DVT.

Assessment of hypoxia tolerance to high-altitude exposure following sleep deprivation

Objectives: The adverse effects of hypoxia and sleep deprivation (SD) have been studied separately but there is little literature on their effects when acting in conjunction. Hence, the effects of SD on hypoxia tolerance and cognitive performance when exposed to altitude were investigated. Material and Methods: In a cross-sectional repetitive measure design, 15 healthy volunteers assessed on cognitive performance were made to perform cognitive tests (Dual Task Test, Stroop Test [ST], and Digit Symbol Substitution Test [DSST] of Psychometric Evaluation Designed for Aviators test battery) on the ground and at a simulated altitude of 17,000 ft in a hypobaric chamber on 4 days. On the 2nd and 3rd day, the tests were done following 2 h of SD the previous night, and on the 4th day, the same was repeated following normal recovery sleep. Heart rate (HR) and respiratory rate (RR) were measured on the ground and 17,000 ft. The Lake Louise Acute Mountain Sickness (LLAMS) scores were used to assess the severity of symptoms of hypoxia and time to arterial oxygen desaturation of 75% was used to measure hypoxia tolerance. Results: Although not statistically significant, the LLAMS scores showed an increasing trend on SD days with an improvement in recovery of sleep. No statistically significant differences in the HR (F = 0.569, P = 0.637) and RR (F = 0.569, P = 0.637) were observed across the days of SD or recovery. The time to oxygen desaturation to 75% also showed no significant effect (F = 0.587, P = 0.625). A statistically significant increase in response times of two cognitive tests (ST and DSST) was observed on exposure to altitude on all 4 days. The three cognitive tests did not show any statistically significant effect following 2 h of SD or recovery. Conclusion: The study could not elicit a statistically significant effect of 2 h of SD across 2 consecutive nights on the cognitive performance measures on exposure to hypoxia.

Retro-fitment of an oxygen system in a transport aircraft of Indian Air Force: Decompression chamber trials to assess system functionality

The aeromedical concerns of sudden onset hypoxia and rapid decompression are an omnipresent threat to flight safety when flying over 10,000 ft. The concept of Time of Useful Consciousness (TUC) provides the aircrew a window to correct his predicament. The issues of hypoxia are mitigated in transport aircraft with cabin pressurization. However, the requirement of an oxygen system in these aircraft is considered essential in an emergency in case of cabin failure of cabin pressurization or rapid decompression, despite adequate TUC, as it provides immediate succor from anxiety, and subtle performance decrements, especially in VIP carriage or casevac roles. With this background, a requirement for retro-fitment of a functional oxygen system of a small transport ac of Indo-German origin into a pressurized medium-lift cargo aircraft of British Origin was envisaged. Toward this, ground-based simulator trials were conducted on the oxygen system to assess its functionality before undertaking flight trials in the aircraft. The assessment consisted of the ground trial of the test oxygen system in the Explosive Decompression Chamber with three experiment protocols. The experimentation involved exposure to a simulated altitude of 15,000 ft for 25 min and rapid decompression from 7000 to 15,000 ft. Physiological parameters, endurance, and flow of oxygen in the system were evaluated. The trial results indicated that the physiological parameters (heart rate, respiratory rate, oxygen saturation [SpO2], and end-tidal carbon dioxide [EtCO2]) were within normal limits during the entire duration of exposure to 15,000 ft and decompression from 7000 ft to 15,000 ft. In addition, the physiological parameters were also within normal limits during exposure to 1 min of simulated hyperventilation. Neither any subjective or objective symptoms of hypoxia were observed nor any appreciation of increased breathing resistance reported by the subjects. The endurance of the system in terms of delivering continuous oxygen flow at 15,000 ft was assessed to be 73 min. From the trials, it was inferred that the oxygen system in a single crew configuration could be used satisfactorily up to the operational ceiling altitude specified for the subject aircraft.

Role of Computed Tomography Scan Chest for Management of COVID-19

Aim: To assess the role of chest computed tomography for management of Covid-19. Study design: Prospective study Place and duration of study: Department of Radiology, Peoples University of Medical & Health Sciences for Women, Nawabshah, Shaheed Benazirabad from 1st August 2020 to 30th September 2021. Methodology: Two hundred patients were enrolled within the age range of 18-70 years. The clinical/medical record of all those patients who were moderately to critically ill assessed in detail. These patients visited the hospital with symptoms of cough, fever, hypoxia, dyspnea, diarrhoea, flu, headache and other related symptoms. All patients underwent chest reverse transcription polymerase chain reaction as well as chest computed tomography scan. The reverse transcription polymerase chain reaction was performed through nasopharyngeal swab. Results: The mean age of the patients was 64.5±5.6 years with 120 (60%) males and 80 (40%) females. The specificity was 75%, sensitivity 100%, positive predictive value 79%, negative predictive value 66.67% and diagnostic accuracy 75%. Conclusion: Computed tomography scan imaging is a most reliable with high sensitivity and non-predictive value Key words: Role, Computed tomography imaging, Management, Covid-19

Microinjection based zebrafish embryo test for the detection of estrogenic substances in slurry based irrigation water and its combined application with yeast estrogen screen

Waste from livestock farms, including manure, is a significant source of estrogenic pollutants in the environment. These wastes have complex matrices, necessitating the implementation of in vivo and in vitro tests in order to investigate their estrogenic effects. However, most current in vivo methods are limited by the toxic effect of livestock waste due to their high concentrations of organic matter. Here we propose a novel in vivo microinjection method which is able to avoid this limitation. In this study, the estrogen content of slurry-based irrigation water extracts from dairy cattle farms was examined using a classical in vitro and the newly developed in vivo method. The limitations of the in vitro system, with its absence of endogenous steroid hormone receptors and subsequent lack of elucidating complex interactions involving the estrogen receptor (ER), are complemented by the in vivo fish test, which allows for a more complete assessment of estrogenicity and toxicity to vertebrate animals. In vitro screenings were performed with the ISO 19040–1:2018 Yeast Estrogen Screen (YES). The YES test showed estrogenic activity in all 32 tested samples, which ranged from 5 to 50518 ng/L in EEQ (E2-Estradiol equivalents). The in vivo microinjection method was developed using a Tg(vtg1:mCherry) transgenic zebrafish embryo model. This model is able to eliminate secondary symptoms of hypoxia that may occur during normal aqueous exposure to high organic matter extracts. Using the microinjection method, a total of 12 samples, out of the 32 samples examined, presented no observable estrogenic effects in fish embryos based on integrated density values. In samples where the fish test showed no estrogenic effect, the liver of the larvae was significantly damaged due to sample toxicity. Our results clearly show that the combination of these methods provides a highly effective screening tool for samples containing high concentrations of organic matter.

Hyperventilation and Hypoxia Hangover During Normobaric Hypoxia Training in Hawk Simulator.

Introduction: In military aviation during high-altitude operations, an oxygen or cabin pressure emergency can impair brain function and performance. There are variations in individuals’ physiological responses to low partial pressure of oxygen and hypoxia symptoms can vary from one exposure to another. The aim of this study was to evaluate how normobaric hypoxia (NH) affects pilots’ minute ventilation and 10 min afterwards on Instrument Landing System (ILS) flight performance in Hawk simulator during a tactical flight sortie. Methods: Fifteen volunteer fighter pilots from the Finnish Air Force participated in this double blinded, placebo controlled and randomized study. The subjects performed three flights in a tactical Hawk simulator in a randomized order with full flight gear, regulators and masks on. In the middle of the flight without the subjects’ knowledge, 21% (control), 8% or 6% oxygen in nitrogen was turned on. Minute ventilation (VE) was measured before, during NH and after NH. Forehead peripheral oxygen saturation (SpO2), wireless ECG and subjective symptoms were documented. The flights were conducted so that both subjects and flight instructors were blinded to the gas mixture. The pilots performed tactical maneuvers at simulated altitude of 20,000 ft or 26,000 ft until they recognized the symptoms of hypoxia. Thereafter they performed hypoxia emergency procedures with 100% oxygen and returned to base (RTB). During the ILS approach, flight performance was evaluated. Results: The mean VE increased during NH from 12.9 L/min (21% O2 on the control flight) to 17.8 L/min with 8% oxygen (p < 0.01), and to 21.0 L/min with 6% oxygen (p < 0.01). Ten minutes after combined hyperventilation and hypoxia, the ILS flight performance decreased from 4.4 (control flight) to 4.0 with 8% oxygen (p = 0.16) and to 3.2 with 6% oxygen (p < 0.01). A significant correlation (r = -0.472) was found between the subjects’ VE during 6% oxygen exposure and the ILS flight performance. Discussion: Hyperventilation during NH has a long-lasting and dose-dependent effect on the pilot’s ILS flight performance, even though the hypoxia emergency procedures are executed 10 min earlier. Hyperventilation leads to body loss of carbon dioxide and hypocapnia which may even worsen the hypoxia hangover.