ArticleAmerican journal of physiology. Heart and circulatory physiology2012
Effect of heat stress on cardiac output and systemic vascular conductance during simulated hemorrhage to presyncope in young men.
Article in American journal of physiology. Heart and circulatory physiology, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 20 papers, 1 of them a synthesis that pooled it.
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Who cites it
20 citing papers in PubMed, 1 synthesis or guideline pooled it, 36 citations in OpenAlex.
- Meta-analysis of heat-induced changes in cardiac function from over 400 laboratory-based heat exposure studies.Nature communications · 2025Pooled it
- Impairments in central cardiovascular function contribute to attenuated reflex vasodilation in aged skin.Journal of applied physiology (Bethesda, Md. : 1985) · 2015Trial
- Normothermic central hypovolemia tolerance reflects hyperthermic tolerance.Clinical autonomic research : official journal of the Clinical Autonomic Research Society · 2014Trial
- Acute volume expansion attenuates hyperthermia-induced reductions in cerebral perfusion during simulated hemorrhage.Journal of applied physiology (Bethesda, Md. : 1985) · 2013Trial
- Sweat loss during heat stress contributes to subsequent reductions in lower-body negative pressure tolerance.Experimental physiology · 2013Trial
- Cerebral and peripheral haemodynamics at rest and in response to orthostasis during 3 days of simulated heatwave.Experimental physiology · 2026Article
- Cerebrovascular regulation during heat stress.Experimental physiology · 2026Review
- Cardiovascular responses to hot skin at rest and during exercise.Temperature (Austin, Tex.) · 2023Review
- Intradialytic Hypotension: Mechanisms and Outcome.Blood purification · 2020Review
- Impact of environmental stressors on tolerance to hemorrhage in humans.American journal of physiology. Regulatory, integrative and comparative physiology · 2019Article
- Phenylephrine increases near-infrared spectroscopy determined muscle oxygenation in men.Journal of clinical monitoring and computing · 2017Article
- Mechanisms of orthostatic intolerance during heat stress.Autonomic neuroscience : basic & clinical · 2016Review
- Instrument to detect syncope and the onset of shock.Proceedings of SPIE--the International Society for Optical Engineering · 2016Article
- Fluid restriction during exercise in the heat reduces tolerance to progressive central hypovolaemia.Experimental physiology · 2015Article
- Local temperature-sensitive mechanisms are important mediators of limb tissue hyperemia in the heat-stressed human at rest and during small muscle mass exercise.American journal of physiology. Heart and circulatory physiology · 2015Article
- Human cardiovascular responses to passive heat stress.Comprehensive Physiology · 2015Review
- Blunted cutaneous vasoconstriction and increased frequency of presyncope during an orthostatic challenge under moderate heat stress in the morning.European journal of applied physiology · 2014Article
- Cerebral oxygenation and hyperthermia.Frontiers in physiology · 2014Review
- Hypercoagulability in response to elevated body temperature and central hypovolemia.The Journal of surgical research · 2013Article
- Heat stress attenuates the increase in arterial blood pressure during isometric handgrip exercise.European journal of applied physiology · 2013Article
Corrections and comments
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Authors and funding
7 authors at 3 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
During moderate actual or simulated hemorrhage, as cardiac output decreases, reductions in systemic vascular conductance (SVC) maintain mean arterial pressure (MAP). Heat stress, however, compromises the control of MAP during simulated hemorrhage, and it remains unknown whether this response is due to a persistently high SVC and/or a low cardiac output. This study tested the hypothesis that an inadequate decrease in SVC is the primary contributing mechanism by which heat stress compromises blood pressure control during simulated hemorrhage. Simulated hemorrhage was imposed via lower body negative pressure (LBNP) to presyncope in 11 passively heat-stressed subjects (increase core temperature: 1.2 ± 0.2°C; means ± SD). Cardiac output was measured via thermodilution, and SVC was calculated while subjects were normothermic, heat stressed, and throughout subsequent LBNP. MAP was not changed by heat stress but was reduced to 45 ± 12 mmHg at the termination of LBNP. Heat stress increased cardiac output from 7.1 ± 1.1 to 11.7 ± 2.2 l/min (P < 0.001) and increased SVC from 0.094 ± 0.018 to 0.163 ± 0.032 l·min(-1)·mmHg(-1) (P < 0.001). Although cardiac output at the onset of syncopal symptoms was 37 ± 16% lower relative to pre-LBNP, presyncope cardiac output (7.3 ± 2.0 l/min) was not different than normothermic values (P = 0.46). SVC did not change throughout LBNP (P > 0.05) and at presyncope was 0.168 ± 0.044 l·min(-1)·mmHg(-1). These data indicate that in humans a cardiac output adequate to maintain MAP while normothermic is no longer adequate during a heat-stressed-simulated hemorrhage. The absence of a decrease in SVC at a time of profound reductions in MAP suggests that inadequate control of vascular conductance is a primary mechanism compromising blood pressure control during these conditions.
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