A method for measuring quantitatively the volume of cerebral blood flow in man by inhalation of nitrous oxide (1) found its first application in a study of the cerebral circulatory effects of low CO2 tension achieved by hyperventilation; of high CO2 tension, and of high and low 02 tensions obtained by inhalation of appropriate gas mixtures (2). Only the first part of this study, the effects of active and passive hyperventilation, has been published in detail (3). The purpose of the present paper is to present the remainder of these findings and to derive from them, together with those of the hyperventilation experiments, evidence bearing on the intrinsic control of the human cerebral circulation as revealed by quantitative measurements.

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The effects of altered arterial tensions of carbon dioxide and oxygen on cerebral blood flow and cerebral oxygen consumption of normal young men

Rupture or laceration of the aorta is a more common result of nonpenetrating traumatic injury than is generally appreciated. Approximately 15 per cent of individuals with traumatic rupture survive temporarily. If the lesion is promptly diagnosed appropriate surgical treatment may be life-saving. Diagnosis may be difficult and at times the rupture may remain clinically silent for variable periods. The natural course from aortic rupture to false aneurysm formation with secondary rupture of the aneurysm may be brief or extend over many years. Surgical treatment of a false aneurysm that has remained stable for a prolonged period has been successful, but in some instances conservative management may be the treatment of choice.

Nonpenetrating Traumatic Injury of the Aorta

SUMMARYSixty-eight convergent dorsal horn neurones have been recorded at the lumbar level in anaesthetized intact rats. All cells received prominent Aα and C fibre afferents and correspondingly could be activated by high and low threshold stimuli applied to the peripheral excitatory receptive field.

Diffuse noxious inhibitory controls (DNIC). I. Effects on dorsal horn convergent neurones in the rat.

Knowledge about the role of the right ventricle in health and disease historically has lagged behind that of the left ventricle. Less muscular, restricted in its role to pumping blood through a single organ, and less frequently or obviously involved than the left ventricle in diseases of epidemic proportions such as myocardial ischemia, cardiomyopathy, or valvulopathy, the right ventricle has generally been considered a mere bystander, a victim of pathological processes affecting the cardiovascular system. Consequently, comparatively little attention has been devoted to how right ventricular dysfunction may be best detected and measured, what specific molecular and cellular mechanisms contribute to maintenance or failure of normal right ventricular function, how right ventricular dysfunction evolves structurally and functionally, or what interventions might best preserve right ventricular function. Nevertheless, even the proportionately limited information related to right ventricular function, its impairment in various disease states, and its impact on the outcome of those diseases suggests that the right ventricle is an important contributor and that further understanding of these issues is of pivotal importance.

For this reason, the National Heart, Lung, and Blood Institute convened a working group charged with delineating in broad terms the current base of scientific and medical understanding about the right ventricle and identifying avenues of investigation likely to meaningfully advance knowledge in a clinically useful direction. The following summary represents the presentations and discussions of this working group.

The right ventricle is affected by and contributes to a number of disease processes, including perhaps most notably pulmonary hypertension caused by a variety of lung or pulmonary vascular diseases (cor pulmonale). Other diseases affect the right ventricle in different ways, including global, left ventricular–, or right ventricular–specific cardiomyopathy; right ventricular ischemia or infarction; pulmonary or tricuspid valvular heart disease; and left-to-right shunts.

The right ventricle pumps the same …

Right Ventricular Function and Failure Report of a National Heart, Lung, and Blood Institute Working Group on Cellular and Molecular Mechanisms of Right Heart Failure

Diffuse noxious inhibitory controls (dnic) .1. effects on dorsal horn convergent neurons in the rat

Clinical evidence of cardiac weakness and incoordination secured by simultaneous records of the force BCG and carotid pulse derivative and interpreted by an electrical analogue

The place of the ballistocardiogram in a Newtonian cardiology; and the new light it sheds on certain old clinical problems.

Studies made by simulating systole at necropsy. V. Estimation of the contour of the left ventricular ejection curve by an adjusted integration of the aortic blood pressure curve.

How best to express the strength of the heart or the effort which goes into its contraction presents a problem. Certainly “work” in the Newtonian sense is not the answer; and another solution, the tension-time, is suggested; its derivatives may also be required. Most measurements of the various aspects of cardiac function which can be expressed quantitatively, such as cardiac output, slope of ascending pulse-wave front and ballistocardiogram, indicate that cardiac function diminishes at a rate of between 0.5 to 2 per cent a year as age advances. There is an apparent exception to this rule, because estimates of cardiac strength based on the classic method, the pulse amplitude, suggest that cardiac strength increases as age advances. An explanation for this apparent discrepancy is advanced. In addition to diminishing in strength, there is an increased tendency for the heart's contraction to become more incoordinate as age advances.

An essay on the strength of the heart and on the effect of aging upon it

ConclusionsThe optimum temperature for the feet of my patients proved to be considerably below their mouth temperature. It corresponded closely with the skin temperature of the feet of normal persons. When this temperature was rigidly maintained comfort was at a maximum and the color of the feet most closely approached the normal. Slight deviations from it were accompanied by pain and cyanosis.It appears reasonable to believe that strict maintenance of the optimum temperature would increase the chances of recovery in many cases of gangrene secondary to peripheral vascular disease.

Isaac Starr

Papers

Clinical evidence of cardiac weakness and incoordination secured by simultaneous records of the force BCG and carotid pulse derivative and interpreted by an electrical analogue

The place of the ballistocardiogram in a Newtonian cardiology; and the new light it sheds on certain old clinical problems.

Studies made by simulating systole at necropsy. V. Estimation of the contour of the left ventricular ejection curve by an adjusted integration of the aortic blood pressure curve.

An essay on the strength of the heart and on the effect of aging upon it

A Thermoregulated Foot Cradle for the Treatment of Peripheral Vascular Disease