assessing performance of the cardiopulmonary system Flashcards
what node produces the heart’s rhythm?
the SA node (specialised cells)
what is the intrinsic depolarisation rate of these cells? and what affects this rate?
110b.p.m
the ANS affects this directly using its two branches the sympathetic nervous system and the parasympathetic nervous system
to what rate does the PNS reduce the heart rate?
it reduces the heart rate from 110 b.p.m to 72 b.p.m
why is controlling our breath essential? and what part of our brain controls it?
this control is essential to do basic things like talking coughing treating underwater… it is controlled at rest by the phrenic nerves in the motor cortex of the pre-frontal gyrus that sends impulses from the medulla to the diaphragm to contract
what are the two subclasses of exercise? and what do they mean?
anaerobic exercise is about power and is classified as high intensity and short duration.
aerobic exercise is about endurance and is classified as low intensity and long duration
the immediate increase in ventilation is mediated by what?
neurogenic afferent from active skeletal muscle
of how many folds can the cardiac output increase while exercising? and is it normal? if not what. is the solution?
it can have a fourfold increase
normal heart rate at rest is 70 b.p.m. IF exercise: the heart rate will be 280 b.p.m which is NOT good. this is a type of arrhythmia (=abnormal heart rate).
therefore the ventricles contract before being full.
how can we calculate the maximum heart rate of an individual?
maximum heart rate = 220-age
with long term training, changes in the heart occur. what are these changes and what do they result in?
the heart becomes bigger and stronger which increases the volume of blood pumped and therefore increases the cardiac output without changing the maximum heart rate while exercising and keeps the same cardiac output at rest because the stroke volume increases but the heart rate decreases.
can the lung volume increase with exercising?
no the lung size is usually predetermined by genetics
what are the two ways in which we can assess the heart?
electrocardiography and echocardiography
what does an electrocardiography measure?
it measure the heart rate, the timing between beats (rhythm) and the way the signal is propagated through the specialised conduction pathway and the myocardium
what are the three phases that can be seen in an ECG?
the P wave, the QRS complex and the T wave.
what is an echocardiography? and what is it used for?
a method of ultrasound imaging which allows someone to look at different cross sections of the heart.
it is useful to assess the heart valves and can be used to estimate the volume of blood in the heart before and after contraction
what methods can be used to measure the lung volume?
traditional spirometry, peak expiratory flow and modern spirometry
