Lung atelectasis refers to collapse or incomplete expansion of pulmonary parenchyma. Note that the term atelectasis is typically used when there is partial collapse, whereas the term collapsed lung is typically reserved for when the entire lung is totally collapsed. Classification.
For a normal adult, it takes close to one minute for a blood cell to circulate the body:-. The stroke volume (SV) of the heart is roughly 60-70ml. The total blood volume (BV) is 4-5L in an individual. Heart Rate (HR) at rest is roughly 60 beats/minute.
Return of systemic blood to the heart is impeded by the pressure inside the chest. The output of the heart is reduced and stroke volume falls. This occurs from 5 to about 14 seconds in the illustration. The fall in stroke volume reflexively causes blood vessels to constrict with some rise in pressure (15 to 20 seconds).