Search results
Results from the WOW.Com Content Network
However, the perfusion rate rises more, resulting in decreased V/Q ratio. Towards the apex of the lungs, the hydrostatic pressure is reduced due to gravity, which lowers the blood flow, thus decreasing perfusion. Since ventilation exceeds perfusion, the V/Q ratio is increased at the apex of the lungs. [1]
This matching may be assessed in the lung as a whole, or in individual or in sub-groups of gas-exchanging units in the lung. On the other side Ventilation-perfusion mismatch is the term used when the ventilation and the perfusion of a gas exchanging unit are not matched. The actual values in the lung vary depending on the position within the lung.
Major factors influencing cardiac output – heart rate and stroke volume, both of which are variable. [1]In cardiac physiology, cardiac output (CO), also known as heart output and often denoted by the symbols , ˙, or ˙, [2] is the volumetric flow rate of the heart's pumping output: that is, the volume of blood being pumped by a single ventricle of the heart, per unit time (usually measured ...
Smoking most commonly leads to diseases affecting the heart and lungs and will commonly affect areas such as hands or feet. First signs of smoking-related health issues often show up as numbness in the extremities, with smoking being a major risk factor for heart attacks, chronic obstructive pulmonary disease (COPD), emphysema, and cancer, particularly lung cancer, cancers of the larynx and ...
The ILR monitors the electrical activity of the heart, continuously storing information in its circular memory (hence the name "loop" recorder) as electrocardiograms (ECGs). Abnormal electrical activity - arrhythmia is recorded by "freezing" a segment of the memory for later review.
When the heart contracts during systole, the contraction compresses the coronary arteries, which prevents perfusion. Therefore, it is only when the heart relaxes, during diastole , that the coronary vessels open up and allow for perfusion; thus CPP is highest during diastole, unlike most other arteries, which experience higher perfusion ...
Monitoring of the heart rate can be performed as part of electrocardiography, but it can also be measured conveniently with specific heart rate monitors. Such heart rate monitors are largely used by performers of various types of physical exercise. A generic cardiac monitor has the following functions: A display of heart rate and heart rhythm
Each Holter system has hardware (called monitor or recorder) for recording the signal, and software for review and analysis of the record. There may be a "patient button" on the front that the patient can press at specific instants such as feeling/being sick, going to bed, taking pills, marking an event of symptoms which is then documented in the symptoms diary, etc.; this records a mark that ...