ArticlePhysiological reports2013
Hypovolemia explains the reduced stroke volume at altitude.
Article in Physiological reports, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers, 1 of them a synthesis that pooled it.
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Who cites it
14 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Change in pulmonary artery pressure upon acute exposure to high altitude: a systematic review and meta-analysis.European respiratory review : an official journal of the European Respiratory Society · 2026Pooled it
- Exercise induced plasma volume expansion lowers cardiovascular strain during 15-km cycling time-trial in acute normobaric hypoxia.PloS one · 2024Trial
- The independent effects of hypovolaemia and pulmonary vasoconstriction on ventricular function and exercise capacity during acclimatisation to 3800 m.The Journal of physiology · 2019Trial
- Quantifying changes in triaxial seismocardiography variability due to sub-optimal volume status.Frontiers in physiology · 2026Article
- Dynamic Arterial Elastance as a Predictor of Intraoperative Fluid Responsiveness in Elderly Patient over 70 Years of Age Undergoing Spine Surgery in the Prone Position Under General Anesthesia: A Validation Study.Journal of clinical medicine · 2025Article
- A change of heart: Mechanisms of cardiac adaptation to acute and chronic hypoxia.The Journal of physiology · 2022Article
- Yogic breathing in hypobaric environment: breathing exercising and its effect on hypobaric hypoxemia and heart rate at 3,650-m elevation.Journal of exercise rehabilitation · 2021Article
- Effect of Exercise-Induced Reductions in Blood Volume on Cardiac Output and Oxygen Transport Capacity.Frontiers in physiology · 2021Article
- Determining the time needed for workers to acclimatize to hypoxia.International journal of biometeorology · 2020Article
- Using Electroencephalography (EEG) Power Responses to Investigate the Effects of Ambient Oxygen Content, Safety Shoe Type, and Lifting Frequency on the Worker's Activities.BioMed research international · 2020Article
- Effect of Ambient Oxygen Content, Safety Shoe Type, and Lifting Frequency on Subject's MAWL and Physiological Responses.International journal of environmental research and public health · 2019Article
- Impairment of left atrial mechanics does not contribute to the reduction in stroke volume after active ascent to 4559 m.Scandinavian journal of medicine & science in sports · 2019Article
- Parasympathetic withdrawal increases heart rate after 2 weeks at 3454 m altitude.The Journal of physiology · 2017Article
- Effect of hypovolemia on efficacy of reflex maintenance of blood pressure on orthostatic challenge.High blood pressure & cardiovascular prevention : the official journal of the Italian Society of Hypertension · 2016Article
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Authors and funding
7 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
During acute altitude exposure tachycardia increases cardiac output (Q) thus preserving systemic O2 delivery. Within days of acclimatization, however, Q normalizes following an unexplained reduction in stroke volume (SV). To investigate whether the altitude-mediated reduction in plasma volume (PV) and hence central blood volume (CBV) is the underlying mechanism we increased/decreased CBV by means of passive whole body head-down (HDT) and head-up (HUT) tilting in seven lowlanders at sea level (SL) and after 25/26 days of residence at 3454 m. Prior to the experiment on day 26, PV was normalized by infusions of a PV expander. Cardiovascular responses to whole body tilting were monitored by pulse contour analysis. After 25/26 days at 3454 m PV and blood volume decreased by 9 ± 4% and 6 ± 2%, respectively (P < 0.001 for both). SV was reduced compared to SL for each HUT angle (P < 0.0005). However, the expected increase in SV from HUT to HDT persisted and ended in the same plateau as at SL, albeit this was shifted 18 ± 20° toward HDT (P = 0.019). PV expansion restored SV to SL during HUT and to an ∼8% higher level during HDT (P = 0.003). The parallel increase in SV from HUT to HDT at altitude and SL to a similar plateau demonstrates an unchanged dependence of SV on CBV, indicating that the reduced SV during HUT was related to an attenuated CBV for a given tilt angle. Restoration of SV by PV expansion rules out a significant contribution of other mechanisms, supporting that resting SV at altitude becomes reduced due to a hypovolemia.
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