Subjective Measures of Workload and Sleep in Australian Army Recruits; Potential Utility as Monitoring Tools

ABSTRACT Introduction Subjective measures may offer practitioners a relatively simple method to monitor recruit responses to basic military training (BMT). Yet, a lack of agreement between subjective and objective measures may presents a problem to practitioners wishing to implement subjective monitoring strategies. This study therefore aims to examine associations between subjective and objective measures of workload and sleep in Australian Army recruits. Materials and Methods Thirty recruits provided daily rating of perceived exertion (RPE) and differential RPE (d-RPE) for breathlessness and leg muscle exertion each evening. Daily internal workloads determined via heart rate monitors were expressed as Edwards training impulse (TRIMP) and average heart rate. External workloads were determined via global positioning system (PlayerLoadTM) and activity monitors (step count). Subjective sleep quality and duration was monitored in 29 different recruits via a customized questionnaire. Activity monitors assessed objective sleep measures. Linear mixed-models assessed associations between objective and subjective measures. Akaike Information Criterion assessed if the inclusion of d-RPE measures resulted in a more parsimonious model. Mean bias, typical error of the estimate (TEE) and within-subject repeated measures correlations examined agreement between subjective and objective sleep duration. Results Conditional R2 for associations between objective and subjective workloads ranged from 0.18 to 0.78, P < 0.01, with strong associations between subjective measures of workload and TRIMP (0.65–0.78), average heart rate (0.57–0.73), and PlayerLoadTM (0.54–0.68). Including d-RPE lowered Akaike Information Criterion. The slope estimate between objective and subjective measures of sleep quality was not significant. A trivial relationship (r = 0.12; CI −0.03, 0.27) was observed between objective and subjective sleep duration with subjective measures overestimating (mean bias 25 min) sleep duration (TEE 41 min). Conclusions Daily RPE offers a proxy measure of internal workload in Australian Army recruits; however, the current subjective sleep questionnaire should not be considered a proxy measure of objective sleep measures.

Is It Possible to Estimate Average Heart Rate from Facial Thermal Imaging?

The remote measurement of heart rate (HR) could have many applications, such as health and emotional conditions monitoring. Currently, methods based on visible cameras have been developed for HR estimation. However, the employment of such techniques with scarce illumination conditions could be challenging. Infrared Thermography (IRT) could be a valuable tool to overcome this limitation. This study investigated the possibility of estimating average HR with facial IRT through a cross-validated machine learning (ML) approach. The correlation coefficient between the estimated and the measured HR was 0.7. Although preliminary, these results demonstrate the feasibility of estimating HR with IRT.

Comparative study of oxiport laryngoscope blade versus miller laryngoscope blade for intubation in neonates and infants during general anesthesia, a prospective randomized controlled study

Neonates and infants are prone to oxygen desaturation during the induction of general anethesia. Pharyngeal oxygen insufflation has been shown to delay the onset and severity of desaturation during apnea. We took this comparative study with the hypothesis that Oxiport Blade delays the time of onset as well as severity of desaturation as compared to Miller Blade. Eighty neonates and infants undergoing general anesthesia with endotracheal intubation were recruited and randomly assigned into two groups:-Oxiport or Miller. (Laryngoscopy performed with Oxiport or Miller Blade respectively). Results were observed in terms of lowest SPO2 attained during Intubation with each Blade, time for 1% desaturation from baseline, desaturation rate, time for intubation and Heart rate. Data from 80 patients were available for final analysis: Oxiport(n=40)-Group O and Miller(n=40)-Group M. Mean lowest SPO2 attained during laryngoscopy in Group O was 97.77±2.81 and with Group M was 92.42±3.71 with a P-value<0.001. The Rate of Saturation achieved in Group O was 0.091±0.018 sec as compared to 0.342±0.122 sec in Group M and p value was <0.001. The time for 1% desaturation from baseline in Group O was 17.69±3.18 sec as compared to 10.4 ±2.09 sec in Group M with p value<0.001. The time for intubation and average heart rate were comparable in both the groups. Apnoeic Laryngeal Oxygen insufflation with Oxiport Blade decreases the incidence and severity of desaturation during intubation in neonates and infants.

Cushing Syndrome is Associated with Increased Stage N2 Sleep and Decreased SWS Partially Reversible After Treatment

The aim of the present study was to evaluate the sleep parameters of patients with Cushing syndrome (CS) at the time of diagnosis and 12-months after treatment. Thirty four newly diagnosed patients with endogenous CS (17 with ACTH-secreting pituitary adenoma, 17 with adrenal CS) and 23 controls with similar age were included in the study. Two polysomnography (PSG) recordings were performed; one at the time of diagnosis and the other 12 months after resolution of hypercortisolemia. Control group had only baseline PSG. Based on the PSG findings, stage N2 sleep was found to be prolonged, stage N3 and REM sleep were shortened in patients with CS. Average heart rate and mean Apnea Hypopnea Index (AHI) score were higher in patients with CS than the control subjects. Sixteen (47.1%) patients with CS and 4 (17.4%) controls had obstructive sleep apnea (OSA; AHI ≥5). There were no significant differences in sleep parameters of patients according to the etiology of CS (adrenal vs. pituitary) patients. Following 12-months of treatment, a significant decrease in stage N2 sleep and a significant increase in stage N3 sleep were detected, but there was no change in terms of AHI. In conclusion, Cushing syndrome has disturbing effects on sleep structure and these effects are at least partially reversible after treatment. However, the increased risk of OSA was not reversed a year after treatment indicating the importance of early diagnosis and treatment of CS.

Imagining How Lines Were Drawn: The Appreciation of Calligraphy and the Facilitative Factor Based on the Viewer’s Rating and Heart Rate

For this study, we examined how recognizing the writing process of calligraphy influences the cognitive and affective processes related to appreciating it, with the aim of contributing to both graphonomics and the psychology of aesthetics. To this end, we conducted two Web-based experiments in which some participants were instructed to view calligraphy by tracing it with their eyes (the tracing method), while others were told to feel free to think and imagine whatever they wanted. Study 1 (N = 103) revealed that the tracing method elicits stronger admiration, inspiration, and empathy in viewers. Study 2 (N = 87) showed that the tracing method decreases the average heart rate of those who do not frequently engage in calligraphy appreciation as they gaze at calligraphy for a minute-and-a-half (during the second half of the stimulus duration); this suggests that the tracing method could keep viewers from becoming bored while looking at calligraphy. In sum, the tracing method has positive effects on viewing calligraphy. From a broader perspective, the results imply that how in detail viewers recognize the process of creating an artwork will be a key determinant of art appreciation. In addition, our findings demonstrate how we can measure cardiac activities using the emerging technology of the photoplethysmogram (PPG).

Developing endurance among children in preschool period

Introduction: Prior research generally confirms the importance of endurance exercises in preschool period and suggests shorter and less intensive exercises. However, little research has been conducted to show and evaluate different types for developing endurance in preschool period. Our research aims to find out which type of exercise is more suitable for developing endurance for a preschool age child compared to an adult, taking into account developmental characteristics. Material and methods: A total of 69 preschool children (40 children aged 3 years and 29 children aged 5 years) were included in the study. We measured their heart rates during two types of endurance exercises (uninterrupted walking vs “method of game”). We compared the average heart rate and the actual frequency curves. Results: Endurance exercise according to the “method of game” allows the child to adjust the effort more individually compared to uninterrupted walking when both exercises are performed with a group of pre-school children. A comparison of heart rate curves showed that when children partook in the “ method of game”, they achieved different heart rate values at the same time. A further analysis of heart rate with 5 selected “time stamps” between the two exercises showed that children achieved statistically significant higher heart rates when performing the “method of game” (1’: Z = 2.20; p = 0.028, r = 0.19; 3 ‘: Z = 4.64; p = 0.00, r = 0.39; 5’: Z = 3.23; p = 0.001, r = 0.27; 8’: Z = 3.82 p = 0.00, r = 0.32; 13 ‘: Z = 3.33; p = 0.001, r = 0.28). The comparison of the mean heart rate values over the entire 13-minute time interval between the execution of the “method of game” (M = 143, SD = 14) and uninterrupted walking (M = 132, SD = 9) was statistically significantly higher in favour of the “method of game” (Wilcox test: Z = 5.83, p = 0.00, r = 0.24). The Mann-Whitney-Test showed that 3-year-old children achieved statistically significantly higher average heart rate during the “method of game” (Z = -2.34 p = 0.020, η² = 0.08) as well as during uninterrupted walking (Z = 3.17 p = 0.002, η² = 0.15). No statistically significant differences between boys and girls were confirmed. Conclusions: Based on the results obtained, we believe that endurance exercise according to the “method of game” is more suitable for a developing preschool child than uninterrupted walking. The “method of game” also allows the simultaneous implementation of endurance exercise in heterogeneous groups, since the children adapt to the effort themselves, regardless of age. We believe that other types of endurance exercises should be researched and all age groups of preschool children should be included in the research.

Ramadan and blood pressure: importance of chronotherapy

Funding Acknowledgements Type of funding sources: None. Background During Ramadan, alterations in the daily patterns of sleep, activities and medication timing might contribute to changes in blood pressure (BP) and heart rate among hypertensive patients. The aim of this study was to examine the effect of medication timing during Ramadan on blood pressure and heart rate in hypertensive subjects taking their treatment once daily. Methods The study prospectively recruited 44 hypertensive patients between April and June 2019, followed up at the cardiology department of our Hospital. A 24-hour pressure monitoring was carried out during two periods: prior to Ramadan and during the last ten days of Ramadan. Results We studied 29 women and 15 men, mean age was 58.7 years. 34% of the patients were diabetics and 16% had coronaropathy. 46% of the patients were on monotherapy, 43% on dual therapy and 11% on a triple antihypertensive therapy. During Ramadan, 57% of the patients took their treatment during the dinner (group1), whereas 43% took their treatment during the Shour (group 2). Average 24hour blood pressure in the whole group was 129 ± 18/74 ± 10 mmHg before Ramadan and 129 ± 19/74 ± 10 mmHg during Ramadan (p > 0.05). Daytime and nighttime mean values of systolic and diastolic blood pressure as well as mean values of heart rate were not different between both periods regardless of age and gender. However, during Ramadan, those who took their treatment after dinner had significant higher values of 24 hour systolic BP, awake systolic and diastolic BP, asleep systolic and diastolic BP than those who took their treatment with the shour (p < 0.05). Conclusion In this study, there were no significant changes in systolic and diastolic blood pressures as well as heart rate during the 2 periods. However, during Ramadan, a slight superiority of taking the treatment with the shour is observed. Average values of BP and heart rate Group 1 Group 2 p 24 hour SBP (mmHg) 134 ± 23 122 ± 6 0.017 24 hour DBP (mmHg) 76 ± 12 70 ± 5 0.052 Awake SBP (mmHg) 138 ± 23 125 ± 6 0.012 Awake DBP (mmHg) 79 ± 12 73 ± 5 0.044 Asleep SBP (mmHg) 127 ± 26 114 ± 12 0.030 Asleep DBP (mmHg) 71 ± 13 65 ± 7 0.045 24 hour average heart rate (bpm) 71 ± 7 70 ± 6 0.524 Awake average heart rate (bpm) 76 ± 7 74 ± 7 0.322 Asleep average heart rate (bpm) 65 ± 7 65 ± 7 0.931 Average values of blood pressure and heart rate in both groups Abstract Figure. 24hour course of blood pressure

Obstructive Sleep Apnea as a Predictor of Arrhythmias in 24-h ECG Holter Monitoring

A relationship between obstructive sleep apnea (OSA) and abnormalities in 24-h electrocardiogram (ECG) Holter monitoring has not been sufficiently documented. The aim of this study was to analyze the relation between the occurrence and the severity of OSA and the parameters of ECG Holter monitoring in a group of patients with diagnosed OSA. Ninety-four patients with clinical suspicion of OSA were qualified for the study (mean age 53.7). All participants underwent a medical history, laboratory tests, 24-h ECG Holter monitoring, and single-night video-polysomnography (vPSG) using the American Academy of Sleep Medicine recommendations. A group of patients with diagnosed OSA was characterized by more frequent occurrence of supraventricular tachycardia (SVT) and ventricular arrhythmias (VPC). A statistically significant positive correlation was shown between the apnea-hypopnea index (AHI) and average heart rate, supraventricular arrhythmias (SVPC) pairs, SVT, and pauses >2.5 s. In regression analysis, higher AHI constituted an independent predicator for the increased number of pauses >2.5 s, SVT, and SVPC pairs in 24-h ECG Holter monitoring. In summary, patients with OSA are characterized by the increased number of abnormalities in 24-h ECG Holter monitoring.

Thyroid function, brain bioelectrical activity and heart rate variability in patients with hypertension

Aim. To study the levels of thyroid-stimulating hormone (TSH) and thyroid hormones (TH), frequency and amplitude parameters of alpha wave, parameters of heart rate variability, hemodynamics and their relationship in patients with hypertension (HTN) and healthy individuals.Material and methods. We studied 75 patients with stage 2 HTN and 70 healthy individuals. All patients underwent an electroencephalography, 24-hour blood pressure monitoring. Weighted average heart rate variability was calculated. We determined blood plasma levels of TSH and TH. Statistical processing, multiple regression and correlation analysis were carried out using the Statistica v. 10.0.1 software package (StatSoft Inc).Results. In patients with HTN, TSH and TH were lower than in the control group by 50% and 38%, respectively. The а-index was also 40% lower. Patients with HTN were characterized by lower amplitude, frequency and power of а-wave, and weighted average heart rate variability by 35%, 13-35%, and 30%, respectively. Pulse wave velocity in patients with HTN exceeded the control group by 18%, and the systemic dynamic response was 2,2 times higher. The groups differed in the characteristics of the relationship of а-wave between the brain lobes and hemispheres with TSH, TH, heart rate variability and hemodynamics.Conclusion. The concentration of TSH and TH is interrelated with the frequency and amplitude parameters of alpha wave, heart rate variability and hemodynamic parameters in hypertensive patients.