Basic observations
Barbara Smith, Linda Field in Nursing Care, 2019
The pulse is one of the most important of all the basic observations. It is taken to assist with the assessment of a patient’s cardiovascular function – in other words, how well the heart and circulation are functioning. If taken and recorded correctly the pulse can give a wealth of information about a patient’s condition. The pulse is recorded for three main reasons: To obtain information on the heart rate, pattern of beats and strength of pulseTo determine the individual’s pulse on admission – that is, to establish a baseline with which further readings can be comparedTo monitor changes in the pulse
Microvascular Architecture and Networks
John H. Barker, Gary L. Anderson, Michael D. Menger in Clinically Applied Microcirculation Research, 2019
There is, furthermore, a second category of observations that require an explanation incorporating vascular architecture and functional behavior of complex vascular units rather than single-vessel elements. A number of observations, particularly under pathophysiological conditions, suggest, on the whole-organ level, a substantial discrepancy between changes of blood flow and changes of tissue metabolism. In order to reconcile such observations with the fundamental concepts of cardiovascular physiology, the possibility has been suggested that microvascular blood flow may be, under specific circumstances, redistributed within a given vascular architecture, and redistribution effects may be associated with variation of overall substrate (e.g., oxygen) extraction in the face of constant perfusion rates.2,11 In other words, a given microvascular system may show, even with the same overall perfusion, quantitatively different exchange characteristics. Under such circumstances, the existence of a “shunt” circulation is often invoked; and it is now recognized that this must be interpreted in a functional rather than morphological sense.
In Vivo Cardiac Measurements in the Conscious Rat
John H. McNeill in Measurement of Cardiac Function, 2020
Pentobarbital sodium anesthesia has been shown to cause significant hypotension in dogs, a phenomenon not observed when animals were premedicated with fentanyl and anesthetized with alpha-chloralose.16 This observation must be interpreted with caution, however, as Bennett and Gardiner17 have shown that urethane-anesthetized rats maintain a normal blood pressure until challenged with a vasopressin antagonist, at which time they develop a profound hypotension. One interpretation of this finding is that since vasopressin was maintaining blood pressure, urethane was clearly inhibiting sympathoadrenal function. This observation is important, since it demonstrates that blood pressure cannot necessarily be used as an indicator of normal cardiovascular function.
Visit-to-visit ultrafiltration volume variability predicts all-cause mortality in patients receiving hemodialysis
Published in Renal Failure, 2023
Quanchao Zhang, Ning Wang, Ling Nie, Caibao Lu, Hongwei Chen, Wenchang He, Moqi Li, Yiqin Wang, Jinghong Zhao, Jiachuan Xiong
Specifically, lower visit-to-visit UV variability means more stable fluid and solute removal between dialysis sessions, whether high or low absolute UV, which is theoretically helpful for the body to establish a balance of volume. This is of vital importance for maintaining cardiovascular function. Patients with higher UV variability are more vulnerable to experiencing large fluctuations in fluid and solutes between dialysis sessions. This poor condition goes against the body’s requirement of maintaining proper multiple-system organ function. For the cardiovascular system, higher UV variability increases the incidence of hypotension caused by excessive ultrafiltration or heart failure caused by insufficient ultrafiltration. Therefore, increased UV variability accompanies an increased risk of cardiovascular function impairment and poor outcomes. From this perspective, the link between higher UV variability and increased all-cause mortality seems reasonable and plausible.
Lycopene alleviates oxidative stress-induced cell injury in human vascular endothelial cells by encouraging the SIRT1/Nrf2/HO-1 pathway
Published in Clinical and Experimental Hypertension, 2023
Wenhai Guo, Danping Huang, Shaodong Li
In the past few years, oxidative stress has been widely involved in many disease processes, including myocardial infarction, atherosclerosis, myocardial ischemia-reperfusion injury, and other cardiovascular diseases (30,31). H2O2, as a major redox metabolite, is essential in redox sensing, signaling, and redox regulation. Supraphysiological concentrations of H2O2 can cause damage to cellular functions, resulting in oxidative stress damage (32). Vascular endothelial cells are an important part of the heart and vascular system, and the nutrition and proper biochemical function of vascular endothelial cells are related to the proper functioning of cardiovascular function (33). The accumulation of ROS in endothelial cells under oxidative stress stimuli induces endothelial dysfunction, which has a major impact on the cardiovascular system and the health of living organisms (34). In the present study, to mimic vascular endothelial cell oxidative stress injury in cardiovascular disease, we used a high concentration of H2O2 to stimulate HMEC-1 and ECV-304 cells. The results showed an increase in ROS and MDA production and a decrease in GSH, GCLC, and GCLM expression in the cells under H2O2 stimulation. Among them, MDA can be used as a marker of oxidative stress damage. In addition, there are antioxidant stress injury substances in the cell, such as GSH as well as other enzyme class and non-enzyme class substances, which can alleviate the oxidative stress injury (35).
Evaluation of induced biological effects in rats by continuous and natural gamma radiation using a physical simulator
Published in International Journal of Radiation Biology, 2020
João Victor da Silva Coutinho, Priscila Santos Ferreira, Jacyra Soares, José Luis Passamai, Marcos Tadeu D’Azeredo Orlando, Sonia Alves Gouvea
There is no work evaluating cardiovascular events at low radiation doses. Results obtained by plestimography did not identify changes in systolic blood pressure. Given the regulatory role of the kidney in the renin-angiotensin-aldosterone system and due to the exposure time of the rats, if the renal tissue was impaired the animals would show signs of cardiovascular changes, as animal models such as 2K1C are used to generate hypertension secondary to renal damage (Dias et al. 2014). There was no change in the renal structure of animals exposed to radiation in our study, nor a difference in the concentration of inflammatory cells, indicating that the kidney maintained its structure and function preserved. Preserving the kidney ensures in part the control of blood pressure and preservation of the cardiovascular function of the animals.
Related Knowledge Centers
- Fick Principle
- Heart Rate
- Physiology
- Stroke Volume
- Circulatory System
- Heart
- Blood Vessel
- Cardiac Output
- End-Diastolic Volume
- End-Systolic Volume