A protocol for an observational cohort study of heat strain and its effect on fetal wellbeing in pregnant farmers in The Gambia

Introduction: Climate change predictions indicate that global temperatures are likely to exceed those seen in the last 200,000 years, rising by around 4°C above pre-industrial levels by 2100 (without effective mitigation of current emission rates). In regions of the world set to experience extreme temperatures, women often work outside in agriculture even during pregnancy. The implications of heat strain in pregnancy on maternal health and pregnancy outcome are not well understood. This protocol describes a study to assess the physiological response of pregnant women to environmental heat stress and the immediate effect this has on fetal wellbeing. Methods and analysis: The study will be performed in West Kiang district, The Gambia; a semi-arid zone in West Africa with daily maximum temperatures ranging from approximately 32 to 40°C. We will recruit 125 pregnant women of all ages who perform agricultural work during their pregnancy. Participants will be followed every two months until delivery. At each study visit fetal growth will be measured by ultrasound scan. During the course of their working day we will take the following measurements: continuous maternal physiological measurements (heart rate, respiratory rate, chest skin temperature and tri-axis accelerometer data); intermittent maternal tympanic core temperature, four point skin temperature, blood pressure; intermittent fetal heart rate and, if eligible, umbilical artery doppler; intermittent environmental measurements of air temperature, humidity, solar radiation and wind speed. Venous blood and urine will be collected at beginning and end of day for biomarkers of heat strain or fetal distress and hydration status.

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A Field Evaluation of Construction Workers’ Activity, Hydration Status, and Heat Strain in the Extreme Summer Heat of Saudi Arabia

Annals of Work Exposures and Health ◽

10.1093/annweh/wxaa029 ◽

2020 ◽

Vol 64 (5) ◽

pp. 522-535 ◽

Cited By ~ 1

Author(s):

Mohammed Al-Bouwarthan ◽

Margaret M Quinn ◽

David Kriebel ◽

David H Wegman

Keyword(s):

Heart Rate ◽

Saudi Arabia ◽

Heat Stress ◽

Heat Exposure ◽

Heat Strain ◽

Construction Workers ◽

Hydration Status ◽

Summer Heat ◽

Cardiovascular Strain ◽

Indoor And Outdoor

Abstract Objectives Assess the impact of summer heat exposure (June–September) on residential construction workers in Al-Ahsa, Saudi Arabia by evaluating (i) heart rate (HR) responses, hydration status, and physical workload among workers in indoor and outdoor construction settings, (ii) factors related to physiological responses to work in hot conditions, and (iii) how well wet-bulb globe temperature-based occupational exposure limits (WBGTOELs) predict measures of heat strain. Methods Twenty-three construction workers (plasterers, tilers, and laborers) contributed 260 person-days of monitoring. Workload energy expenditure, HR, fluid intake, and pre- and postshift urine specific gravity (USG) were measured. Indoor and outdoor heat exposures (WBGT) were measured continuously and a WBGTOEL was calculated. The effects of heat exposure and workload on heart rate reserve (HRR), a measure of cardiovascular strain, were examined with linear mixed models. A metric called ‘heat stress exceedance’ (HSE) was constructed to summarize whether the environmental heat exposure (WBGT) exceeded the heat stress exposure limit (WBGTOEL). The sensitivity and specificity of the HSE as a predictor of cardiovascular strain (HRR ≥30%) were determined. Results The WBGTOEL was exceeded frequently, on 63 person-days indoors (44%) and 91(78%) outdoors. High-risk HRR occurred on 26 and 36 person-days indoors and outdoors, respectively. The HSE metric showed higher sensitivity for HRR ≥30% outdoors (89%) than indoors (58%) and greater specificity indoors (59%) than outdoors (27%). Workload intensity was generally moderate, with light intensity work more common outdoors. The ability to self-pace work was associated with a lower frequency of HRR ≥30%. USG concentrations indicated that workers began and ended their shifts dehydrated (USG ≥1.020). Conclusions Construction work where WBGTOEL is commonly exceeded poses health risks. The ability of workers to self-pace may help reduce risks.

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A real-time heat strain risk classifier using heart rate and skin temperature

Physiological Measurement ◽

10.1088/0967-3334/29/12/n01 ◽

2008 ◽

Vol 29 (12) ◽

pp. N85-N79 ◽

Cited By ~ 24

Author(s):

Mark J Buller ◽

William A Latzka ◽

Miyo Yokota ◽

William J Tharion ◽

Daniel S Moran

Keyword(s):

Heart Rate ◽

Skin Temperature ◽

Real Time ◽

Heat Strain

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Heat Strain in Protective Clothing Following Hot-Wet or Hot-Dry Heat Acclimation

Canadian Journal of Applied Physiology ◽

10.1139/h96-009 ◽

1996 ◽

Vol 21 (2) ◽

pp. 90-108 ◽

Cited By ~ 20

Author(s):

Tom M. McLellan ◽

Yukitoshi Aoyagi

Keyword(s):

Heart Rate ◽

Skin Temperature ◽

Rectal Temperature ◽

Protective Clothing ◽

Intermittent Exercise ◽

Sweat Rate ◽

Heat Acclimation ◽

Heat Strain ◽

Mean Skin Temperature ◽

Time Required

The purpose of the present study was to compare the heat strain while wearing nuclear, biological, and chemical (NBC) protective clothing following a hot-wet (HW) or hot-dry (HD) heat acclimation protocol. Twenty-two males were assigned to groups HW (n = 7), HD (n = 8), or control (C, n = 7). Subjects were evaluated during continuous treadmill walking while wearing lightweight combat clothing and during intermittent exercise while wearing the NBC protective clothing. While wearing Combat clothing, greater decreases in rectal temperature (Tre), mean skin temperature [Formula: see text], and heart rate were observed for both acclimation groups. For the NBC clothing trials, lower Tre, [Formula: see text], and heart rates were observed only for group HW. The time required for Tre to increase 1.0 °C and 1.5 °C was significantly delayed for groups HW and HD. Sweat evaporation increased for HW, whereas no change was found for HD. The most significant changes in Tre, [Formula: see text], and heart rate while wearing the NBC protective clothing occur following heat acclimation that involves wearing the clothing during exercise. Key words: rectal temperature, mean skin temperature, heart rate, sweat rate

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Does Dehydration Affect the Adaptations of Plasma Volume, Heart Rate, Internal Body Temperature, and Sweat Rate During the Induction Phase of Heat Acclimation?

Journal of Sport Rehabilitation ◽

10.1123/jsr.2019-0174 ◽

2020 ◽

Vol 29 (6) ◽

pp. 847-850

Author(s):

Yasuki Sekiguchi ◽

Erica M. Filep ◽

Courteney L. Benjamin ◽

Douglas J. Casa ◽

Lindsay J. DiStefano

Keyword(s):

Heart Rate ◽

Body Temperature ◽

Skin Temperature ◽

Plasma Volume ◽

Sweat Rate ◽

Physiological Responses ◽

Heat Acclimation ◽

Hydration Status ◽

Induction Phase ◽

Internal Body

Clinical Scenario: Exercise in the heat can lead to performance decrements and increase the risk of heat illness. Heat acclimation refers to the systematic and gradual increase in exercise in a controlled, laboratory environment. Increased duration and intensity of exercise in the heat positively affects physiological responses, such as higher sweat rate, plasma volume expansion, decreased heart rate, and lower internal body temperature. Many heat acclimation studies have examined the hydration status of the subjects exercising in the heat. Some of the physiological responses that are desired to elicit heat acclimation (ie, higher heart rate and internal body temperature) are exacerbated in a dehydrated state. Thus, euhydration (optimal hydration) and dehydration trials during heat acclimation induction have been conducted to determine if there are additional benefits to dehydrated exercise trials on physiological adaptations. However, there is still much debate over hydration status and its effect on heat acclimation. Clinical Question: Does dehydration affect the adaptations of plasma volume, heart rate, internal body temperature, skin temperature, and sweat rate during the induction phase of heat acclimation? Summary of Findings: There were no observed differences in plasma volume, internal body temperature, and skin temperature following heat acclimation in this critically appraised topic. One study found an increase in sweat rate and another study indicated greater changes in heart rate following heat acclimation with dehydration. Aside from these findings, all 4 trials did not observe statistically significant differences in euhydrated and dehydrated heat acclimation trials. Clinical Bottom Line: There is minimal evidence to suggest that hydration status affects heat acclimation induction. In the studies that met the inclusion criteria, there were no differences in plasma volume concentrations, internal body temperature, and skin temperature. Strength of Recommendation: Based on the Oxford Centre for Evidence-Based Medicine Scale, Level 2 evidence exists.

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The relation between heat strain and hydration status in the food industry employees in Mashhad, 2014

Polish Annals of Medicine ◽

10.29089/2017.17.00040 ◽

2018 ◽

Author(s):

Somayeh Bolghanabadi ◽

◽

Aliakbar Mohammadi ◽

Baharam Kohnavard ◽

Mohamadbagher Delkhosh ◽

...

Keyword(s):

Food Industry ◽

Heat Strain ◽

Hydration Status

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COVID-19 Pandemic-Related Anxiety in Pregnant Women

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18147221 ◽

2021 ◽

Vol 18 (14) ◽

pp. 7221

Author(s):

Urszula Nowacka ◽

Szymon Kozlowski ◽

Marcin Januszewski ◽

Janusz Sierdzinski ◽

Artur Jakimiuk ◽

...

Keyword(s):

Anxiety Disorder ◽

Pregnant Women ◽

Generalized Anxiety Disorder ◽

Social Contact ◽

Anxiety Level ◽

Generalized Anxiety ◽

Daily Routine ◽

Main Concern ◽

Pregnancy Anxiety ◽

Fetal Wellbeing

The COVID-19 pandemic outbreak influenced general and mental health worldwide. The objective of this study was to assess the anxiety level during the COVID-19 pandemic among pregnant women and compare it between COVID-infected and non-infected groups. We prospectively assessed the daily routine and anxiety level using a bespoke questionnaire and GAD-7 scale validated for pregnant women. With logistic regression, we established possible risk factors of generalized anxiety disorder spectrum and main causes of concern. The dataset included 439 responders of our survey. Of which, 21% had COVID-19 infection during pregnancy; 38% were screened for possible generalized anxiety disorder and the proportion was higher in women who suffered from COVID-19 (48% vs. 35%, p = 0.03). Pre-pregnancy anxiety or depression diagnosis and intentional social contact avoidance increased the risk of anxiety (aOR 3.4 and 3.2). Fetal wellbeing was the main concern for 66% of the responders. The COVID-19 pandemic and related restrictions substantially altered daily lives of pregnant women, exaggerating the prevalence of anxiety compared with the pre-COVID-19 studies (38% vs. 15%). COVID-19 infection during pregnancy was associated with increased levels of generalized anxiety scores. Patient-tailored psychological support should be a mainstay of comprehensive antenatal medical care in order to avoid anxiety- and stress-related complications.

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Wireless Fetal Heart Rate Monitoring in Inpatient Full-Term Pregnant Women: Testing Functionality and Acceptability

PLoS ONE ◽

10.1371/journal.pone.0117043 ◽

2015 ◽

Vol 10 (1) ◽

pp. e0117043 ◽

Cited By ~ 9

Author(s):

Adeline A. Boatin ◽

Blair Wylie ◽

Ilona Goldfarb ◽

Robin Azevedo ◽

Elena Pittel ◽

...

Keyword(s):

Heart Rate ◽

Pregnant Women ◽

Fetal Heart Rate ◽

Fetal Heart ◽

Full Term ◽

Heart Rate Monitoring ◽

Fetal Heart Rate Monitoring

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The effects of oxytocin and atosiban on the modulation of heart rate in pregnant women

The Journal of Maternal-Fetal & Neonatal Medicine ◽

10.3109/14767058.2016.1172564 ◽

2016 ◽

Vol 30 (3) ◽

pp. 329-333 ◽

Cited By ~ 5

Author(s):

Amir Weissman ◽

Rana Swed Tobia ◽

Yechiel Z. Burke ◽

Olga Maxymovski ◽

Arie Drugan

Keyword(s):

Heart Rate ◽

Pregnant Women

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Cardiovascular responses to head-stand posture

Journal of Applied Physiology ◽

10.1152/jappl.1963.18.5.987 ◽

1963 ◽

Vol 18 (5) ◽

pp. 987-990 ◽

Cited By ~ 4

Author(s):

Shanker Rao

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

High Pressure ◽

Blood Flow ◽

Arterial Pressure ◽

Skin Temperature ◽

Cardiovascular Responses ◽

Posterior Tibial Artery ◽

Nervous Control ◽

Posterior Tibial

Reports of cardiovascular responses to head-stand posture are lacking in literature. The results of the various responses, respectively, to the supine, erect, and head-stand posture, are as follows: heart rate/min 67, 84, and 69; brachial arterial pressure mm Hg 92, 90, and 108; posterior tibial arterial pressure mm Hg 98, 196, and 10; finger blood flow ml/100 ml min 4.5, 4.4, and 5.2; toe blood flow ml/100 ml min 7.1, 8.1, and 3.4; forehead skin temperature C 34.4, 34.0 and 34.3; dorsum foot skin temperature C 28.6, 28.2, and 28.2. It is inferred that the high-pressure-capacity vessels between the heart level and posterior tibial artery have little nervous control. The high-pressure baroreceptors take active part in postural adjustments of circulation. The blood pressure equating mechanism is not as efficient when vital tissues are pooled with blood as when blood supply to them is reduced. man; heart rate; blood flow; skin temperature Submitted on January 3, 1963

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