Responses in Size, Output and Efficiency of the Human Heart to Acute Alteration in the Composition of Inspired Air

Keys, Ancel; Stapp, J.; Violante, A

doi:10.1152/ajplegacy.1943.138.5.763

Cited by 39 publications

(16 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Daniell and Bagwell (1968), who sutured an isotonic gauge on the left ventricle and measured left ventricular size during oxygen breathing, found increases in the measured value but no detailed description of the method they used was given and they themselves declared that the figures did not indicate absolute values. Keys et al (1943) reported that heart size as measured by roentgenkymography did not change by oxygen breathing. However, it is questionable whether roentgenkymography is sensitive enough to detect the small, 1 or 2 percent reductions demonstrated in the present study.…”

Section: Discussionmentioning

confidence: 99%

Reduction of left ventricular epicardial segment length by 100% oxygen breathing in open-chest dogs.

Ishikawa

Kanamasa

Yamakado

et al. 1982

Tohoku J. Exp. Med.

View full text Add to dashboard Cite

We conducted this study in order to learn whether or not oxygen inhalation reduces left ventricular size, one of the major determinants of myocardial oxygen demand. In 11 open-chest dogs, a Mercury-in-Silastic gauge was applied to measure left ventricular circumferential length while the dogs were being ventilated with either room air or 100% oxygen. Four characteristic notches were identified on the resulting length curve : L1, length at the beginning of ejection; L2, length at the end of ejection; L3, length in early diastole; and L4, length at end diastole, L1 was shortened from 24.9+10.5 to 24.4+9.9 mm (a decrease of 1.4+2.1%) by oxygen breathing, L2 was also shortened from 26.8+11.5 to 26.2+10.7 mm (a decrease of 1.5+2.9%), L3 from 17.5+4.4 to 17.4±4.3 mm (a decrease of 0.7+ 2.7%) and L4 from 17.7±4.8 to 17.5±4.7 mm (a decrease of 1.3±2.4%). These changes all disappeared when the inspiratory gas was changed from oxygen back to air. Heart rate and left ventricular end-diastolic pressure showed no significant changes but were accompanied by a slight reduction in aortic pressure and myocardial contractile force. This study demonstrated a small but consistent reduction in left ventricular circumferential length by oxygen breathing. This reduction in left ventricular size will reduce left ventricular tension and thus result in reduction of left ventricular myocardial oxygen demand when oxygen inhalation is applied to patients with ischemic heart disease.--oxygen inhalation therapy; myocardium; myocardial ischemia; left ventricle

show abstract

Section: Discussionmentioning

confidence: 99%

Reduction of left ventricular epicardial segment length by 100% oxygen breathing in open-chest dogs.

Ishikawa

Kanamasa

Yamakado

et al. 1982

Tohoku J. Exp. Med.

View full text Add to dashboard Cite

show abstract

“…arterial stiffness; vascular resistance; cardiac output; carbon dioxide VARIATIONS IN OXYGEN TENSION beyond the physiological range have complex effects on cardiovascular function. Hypoxia and hyperoxia have been studied extensively and shown to alter heart rate, cardiac output, and vascular resistance (1,10,16,23,29,47). A variety of mechanisms contribute to these cardiovascular responses after changes in oxygen tension.…”

mentioning

confidence: 99%

“…This is important because carbon dioxide has profound effects on cardiovascular function through local vascular, chemoreceptor-mediated, and central effects (38). Both hyperoxia and hypoxia stimulate ventilation and reduce arterial carbon dioxide tension (14,23). It is therefore possible that some of the changes attributed to alterations in oxygen tension may in fact be caused by these secondary changes in ventilation.…”

mentioning

confidence: 99%

Effects of short-term isocapnic hyperoxia and hypoxia on cardiovascular function

Thomson

Drummond²,

Waring³

et al. 2006

Journal of Applied Physiology

103

View full text Add to dashboard Cite

. Effects of short-term isocapnic hyperoxia and hypoxia on cardiovascular function. J Appl Physiol 101: 809 -816, 2006; doi:10.1152/japplphysiol.01185.2005.-Both hypoxia and hyperoxia have major effects on cardiovascular function. However, both states affect ventilation and many previous studies have not controlled CO 2 tension. We investigated whether hemodynamic effects previously attributed to modified O 2 tension were still apparent under isocapnic conditions. In eight healthy men, we studied blood pressure (BP), heart rate (HR), cardiac index (CI), systemic vascular resistance index (SVRI) and arterial stiffness (augmentation index, AI) during 1 h of hyperoxia (mean end-tidal O 2 79.6 Ϯ 2.0%) or hypoxia (pulse oximeter oxygen saturation 82.6 Ϯ 0.3%). Hyperoxia increased SVRI (18.9 Ϯ 1.9%; P Ͻ 0.001) and reduced HR (Ϫ10.3 Ϯ 1.0%; P Ͻ 0.001), CI (Ϫ10.3 Ϯ 1.7%; P Ͻ 0.001), and stroke index (SI) (Ϫ7.3 Ϯ 1.3%; P Ͻ 0.001) but had no effect on AI, whereas hypoxia reduced SVRI (Ϫ15.2 Ϯ 1.2%; P Ͻ 0.001) and AI (Ϫ10.7 Ϯ 1.1%; P Ͻ 0.001) and increased HR (18.2 Ϯ 1.2%; P Ͻ 0.001), CI (20.2 Ϯ 1.8%; P Ͻ 0.001), and pulse pressure (13.2 Ϯ 2.3%; P ϭ 0.02). The effects of hyperoxia on CI and SVRI, but not the other hemodynamic effects, persisted for up to 1 h after restoration of air breathing. Although increased oxidative stress has been proposed as a cause of the cardiovascular response to altered oxygenation, we found no significant changes in venous antioxidant or 8-iso-prostaglandin F 2␣ levels. We conclude that both hyperoxia and hypoxia, when present during isocapnia, cause similar changes in cardiovascular function to those described with poikilocapnic conditions.

show abstract

“…At a simulated altitude of 6,000 m., they found a doubling of minute volume, a 75 per cent increase in stroke volume, and a decrease of venous saturation to 54 to 61 per cent, from 68 to 72 per cent observed at atmospheric pressure. In contrast with these results, Keys et al (19), using the less indirect technic of roentgenkymography, reported little or no increase in stroke volume with gas mixtures corresponding to an altitude of 18,000 to 28,000 feet.…”

Section: 000 Feet)mentioning

confidence: 78%

The Indirect Measurement of Mean Venous Oxygen Tension During Anoxia

Davis

1944

J. Clin. Invest.

View full text Add to dashboard Cite

Responses in Size, Output and Efficiency of the Human Heart to Acute Alteration in the Composition of Inspired Air

Cited by 39 publications

References 0 publications

Reduction of left ventricular epicardial segment length by 100% oxygen breathing in open-chest dogs.

Reduction of left ventricular epicardial segment length by 100% oxygen breathing in open-chest dogs.

Effects of short-term isocapnic hyperoxia and hypoxia on cardiovascular function

The Indirect Measurement of Mean Venous Oxygen Tension During Anoxia

Contact Info

Product

Resources

About