lab 13 and 14 cardiac function I and II Flashcards
what is the procedure for inserting the Swan Ganz catheter?
it is inserted through the jugular or femoral vein and then into the right atrium, right ventricle and then into the pulmonary artery. the tip senses pressure; it also has a ballon just prior to the tip; the pressures detected can be used as a guide to indicate the position of the catheter
what is central venous pressure?
it is the pressure in the thoracic vena cava right next to the right atrium and is considered equal to right atrial pressure under most circmstances
what can central venous pressure be used to measure?
fluid replacement therapy or heart failure
how is the pulmonary arterial wedge pressure obtained?
the catheter is advanced into a branch of the pulmonary artery and the balloon is inflated to occlude flow through that branch. the pulmonary wedge pressure is then measured;
what can the pawp be used to measure?
the function of the left heart; the PAWP reflects pressure in the left atrium; it thus also respresents the left ventricular pressure at end diastolic pressure
how do you measure cardiac output with the indicator dilution method?
the indicator (temperature) is injected as a rapud bolus through the proximal injection part; temperature changes are measured by the termistor near the tip of the catheter in the pulmonary artery; the cardaic output is calculated from the measured temperature change over time CO=(initial blood-injected temp difference)-computation constant /integral of temp change over time
how do you evaluate the work done by the heart in a pressure volume loop?
it is the shaded area in the pressrure-volume loop
what does the frank-starling law say about the relationship of cardiac output and preload?
cardiac output changes at preload changes.
what is preload directly related to?
end diastolic volume and end diastolic pressure
