The effect of atmospheric pressure on oxygen saturation and dyspnea: the Tromsø study

The influence of synoptic conditions on interdiurnal atmospheric pressure changes in Poland

The aim of the presented study was to characterize the territory of Poland in terms of the frequency of occurrence of specific values of IAPC (interdiurnal atmospheric pressure changes) and to determine synoptic situations accompanying their particularly high values. The study is based on the daily mean atmospheric pressure data from the years 1966-2022 taking from 48 meteorological stations in Poland. In the presented paper four IAPC categories were used: A < 4.0 hPa (weak sense of change), B 4.1-8.0 (moderate sense of change), C 8.1-12.0 (strong sense of change), and D > 12.1 (very strong sense of change). Taking into account the negative impact on human health and well-being of the IAPC value, and especially its declines (conductive to the increase of suicides, heart and kidney diseases, asthma), the most unfavorable in this respect in Poland is the northern part of the country. The greatest frequency of synoptic situations causing the above-mentioned influence occurs in the cold half of the year, especially in winter. In turn the beneficial impact of the increase in IAPC on human health and well-being in terms of blood oxygenation and reduced suicide mortality caused by IAPC also occurs in the northern Poland. The frequency of synoptic situations felt in this respect is also highest in the cold half of the year.

The Potential Interplay Between HIF-1α, Angiogenic, and Autophagic Signaling During Intermittent Hypoxic Exposure and Exercise

Berkemeier, Quint N., Michael R. Deyhle, James J. McCormick, Kurt A. Escobar, and Christine M. Mermier. The potential interplay between HIF-1α, angiogenic, and autophagic signaling during intermittent hypoxic exposure and exercise High Alt Med Biol. 25:326-336, 2024.-Environmental hypoxia as a result of decreased barometric pressure upon ascent to high altitudes (>2,500 m) presents increased physiological demands compared with low altitudes, or normoxic environments. Competitive athletes, mountaineers, wildland firefighters, military personnel, miners, and outdoor enthusiasts commonly participate in, or are exposed to, forms of exercise or physical labor at moderate to high altitudes. However, the majority of research on intermittent hypoxic exposure is centered around hematological markers, and the skeletal muscle cellular responses to exercise in hypoxic environments remain largely unknown. Two processes that may be integral for the maintenance of cellular health in skeletal muscle include angiogenesis, or the formation of new blood vessels from preexisting vasculature and autophagy, a process that removes and recycles damaged and dysfunctional cellular material in the lysosome. The purpose of this review is to is to examine the current body of literature and highlight the potential interplay between low-oxygen-sensing pathways, angiogenesis, and autophagy during acute and prolonged intermittent hypoxic exposure in conjunction with exercise. The views expressed in this paper are those of the authors and do not reflect the official policy of the Department of Army, DOD, DOE, ORAU/ORISE or U.S. Government.

The Development of Algorithms for Individual Ranges of Body Temperature and Oxygen Saturation in Healthy and Frail Individuals

BACKGROUND/OBJECTIVES

Individual habitual conditions entail a risk during the interpretation of vital parameters. We developed algorithms for calculating, validating, and interpreting individual normal ranges of body temperature and oxygen saturation.

METHODS

In total, 70 healthy individuals aged 27 to 80 and 52 frail individuals aged 60 to 100 were included. Data on individual conditions comprised age, gender, physical ability, chronic disease, and medication. Ear temperature and oxygen saturation were measured for five mornings before the participants got out of bed and consumed medicine, food, or drink.

RESULTS

The range for body temperature was 34.3 °C to 37.7 °C, with a variation of 0.7 °C ± 0.4 °C. The variation in minimum and maximum temperatures was 2.4 °C vs. 2.7 °C and 2.9 °C vs. 2.3 °C in healthy and frail subjects, respectively. The range for oxygen saturation was 85% to 99% in healthy individuals and 75% to 100% in frail individuals. The variation between minimum and maximum oxygen saturation was 13% vs. 25% and 4% vs. 17% in healthy and frail subjects, respectively.

CONCLUSIONS

To promote the implementation of precision medicine in clinical practice, it is necessary to interpret body temperature and oxygen saturation based on individual habitual conditions. Interpreting deviations from an individual's normal ranges allows healthcare professionals to provide necessary treatment without delay, which can be decisive in preventing further deterioration.

Pulse oximetry in pediatric care: Balancing advantages and limitations

BACKGROUND

Pulse oximetry has become a cornerstone technology in healthcare, providing non-invasive monitoring of oxygen saturation levels and pulse rate. Despite its widespread use, the technology has inherent limitations and challenges that must be addressed to ensure accurate and reliable patient care.

AIM

To comprehensively evaluate the advantages, limitations, and challenges of pulse oximetry in clinical practice, as well as to propose recommendations for optimizing its use.

METHODS

A systematic literature review was conducted to identify studies related to pulse oximetry and its applications in various clinical settings. Relevant articles were selected based on predefined inclusion and exclusion criteria, and data were synthesized to provide a comprehensive overview of the topic.

RESULTS

Pulse oximetry offers numerous advantages, including non-invasiveness, real-time feedback, portability, and cost-effectiveness. However, several limitations and challenges were identified, including motion artifacts, poor peripheral perfusion, ambient light interference, and patient-specific factors such as skin pigmentation and hemoglobin variants. Recommendations for optimizing pulse oximetry use include technological advancements, education and training initiatives, quality assurance protocols, and interdisciplinary collaboration.

CONCLUSION

Pulse oximetry is crucial in modern healthcare, offering invaluable insights into patients' oxygenation status. Despite its limitations, pulse oximetry remains an indispensable tool for monitoring patients in diverse clinical settings. By implementing the recommendations outlined in this review, healthcare providers can enhance the effectiveness, accessibility, and safety of pulse oximetry monitoring, ultimately improving patient outcomes and quality of care.

The short-term effect of weather variables on heart rate variability in patients after open-heart surgery

The aim of the study was to detect the associations between heart rate variability (HRV) and weather variables in patients who underwent coronary artery bypass grafting or valve surgery. The study was performed in Kaunas, Lithuania, during 2008-2012. We used data of 220 patients. HRV was assessed by a 5-minute electrocardiogram. The data were collected at 1.5 months, 1 year, and 2 years after the surgery (495 measurements). A negative association of standard deviation of beat-to-beat interval (SDNN), very low frequency (VLF), low frequency, and high frequency (HF) powers with a decrease in air temperature (T) during a 3-day period in the range of T < 1°C wind speed >2.75 knots 2 days before, and the daily North Atlantic Oscillation indices were observed. The effect of wind speed on SDNN and VLF power was stronger in males. Two days after relative humidity >89%, a lower mean VLF and higher HF in normalized units were found; in females, this effect was stronger 1.5 months after the surgery. Among patients after open-heart surgery, the HRV variables may be related to specific weather changes and the effect of weather was different for males and females and at different times after the surgery.

Clinical features and health-threatening conditions of the trek to Capanna Margherita

BACKGROUND

Since trips to high altitude have become popular, reports on clinical and environmental characteristics during expeditions to popular destinations are needed.

METHODS

A group of 15 healthy adults was monitored during a trek to Capanna Margherita (4556 m). A hypoxic stress test was applied before the expedition started. Environmental characteristics were acquired with a portable device. Vital signs were compared at low and high altitude, and altitude sickness was diagnosed by the Lake Louise scoring system. Ocular symptoms and intraocular pressure were recorded.

RESULTS

Temperature ranged from -3.5 to 31.3 °C and relative humidity from 36 to 95% during the trek. Acute mountain sickness was diagnosed in 40% of participants, more frequently in women, and slightly associated with a greater drop in SpO2. Heart rate and blood pressure increased, while peripheral saturation and intraocular pressure decreased, in response to altitude hypoxia.

CONCLUSIONS

Rapid ascents, as in the most common expedition plans, should be carefully supervised because of the common occurrence of AMS, especially in women. Among organ districts, the eye should deserve more attention in high-altitude medicine. Analyses of environmental conditions, together with predictive methods and early identification of health-threatening conditions, are of great value in supporting further recreational, professional and scientific expeditions to the most intriguing altitude sites.

The effects of weather on depressive symptoms in patients after cardiac surgery

Patients with cardiovascular disease have depression more often than the general population does. The aim of the study was to detect the associations between the psychological state and weather variables in patients who underwent coronary artery bypass grafting or valve surgery. The prospective study was performed during 2008-2012 in Kaunas, Lithuania. The psychological state of 233 patients was assessed by using the Symptom Checklist-90-Revised instrument. The assessment was carried out at 1.5 months, 1 year, and 2 years after the surgery. A sample of 531 measurements of psychological states was used. To investigate the relationships between psychological scores and daily weather variables, a mixed linear model was used adjusting for sex, the type of surgery, age, the marital status, the presence of arterial hypertension, diabetes, major depressive disorders, dysthymic disorders, agoraphobia, smoking before surgery, and myocardial infarction in the anamnesis. The mean somatisation score and air temperature on the second day prior to the survey were found to have a negative correlation in the multivariate model. Lower mean scores of anxiety and depression were linked to hotter days (air temperature >16.25°C on the second day) that did not occur in July or August. During colder days (air temperature <0.35°C), a higher mean score of anxiety and phobic anxiety was observed. A higher mean score of somatizations, depression, and anxiety was seen on the second day after the day with wind speed ≤2.85 kt and on the day after the day with relative humidity <66%. Both a decrease and an increase in daily atmospheric pressure were associated with a higher depression score. Our results confirm that among patients after open heart surgery, psychosomatic complaints are related to some weather changes. The obtained results can help to determine the complexity of weather patterns linked to poorer psychological health.

The Space and Terrestrial Weather Variations as Possible Factors for Ischemia Events in Saint Petersburg

The Space and Terrestrial Weather (Weather Complex) impact on ischemia cases in Saint Petersburg is investigated. The results show the main feature of the Weather Complex when it was related to the days of the different ischemia situations in the different ischemia people gender groups. The data treatment was done with some elements of the Folder Epochs Method, Cluster Analysis and the Mann–Whitney hypothesis test criterion.

Underlying conditions contributing to breathlessness in the population

PURPOSE OF REVIEW

Assessment of underlying conditions that contribute to breathlessness is fundamental for symptom management. This review aims to summarize the knowledge from the past two years on the most common underlying conditions among individuals with breathlessness in the general population and to identify research gaps.

RECENT FINDINGS

Nine studies from the last two years were included in the review; two studies systematically assessed underlying conditions among breathless individuals in the general population. The modified Medical Research Council (mMRC) scale was used in eight of nine studies. Respiratory diseases were the main underlying condition (40-57%), of which asthma was the most common (approx. 25%), and chronic obstructive pulmonary disease was particularly strongly associated with breathlessness. Other conditions prevalent among breathless individuals included heart diseases, anxiety, depression, and obesity, and several conditions often co-existed.

SUMMARY

Breathlessness in the general population is common and associated with several underlying conditions. Respiratory disease is the most commonly reported underlying condition. Refined methods such as machine learning could be useful to study the complex interplay between multiple underlying causes of breathlessness and impact on outcomes such as quality of life and survival.

Influence of light-dark cycle on delayed recovery from isoflurane anesthesia induced by hypnotics in mice

We previously reported that brotizolam, but not suvorexant, delayed recovery from isoflurane anesthesia in mice. However, the effects of hypnotics may be altered by the circadian rhythm. Locomotor activity was measured using sighted (ICR and C57BL/6J) and blind (FVB/N and C3H/HeN) mice, and the effects of hypnotics on isoflurane anesthesia were compared during the light and dark periods. In sighted mice, recovery induced by brotizolam was delayed in the light period, while that by suvorexant was delayed in the dark period. In C57BL/6J mice, delayed recovery induced by brotizolam was marked, and that by suvorexant was observed in the light and dark periods. Locomotor activity was low in the last 6 h of the dark period in blind mice, and was similar to that in the light period. In blind mice, delayed recovery induced by brotizolam was identical in both periods, while suvorexant did not influence recovery from isoflurane anesthesia. These results suggest that the effects of hypnotics on isoflurane anesthesia are altered by the circadian rhythm and that daily light-dark stimuli may be required for the chronopharmacological effects of hypnotics.