NRS 440 Exam 1 Questions with 100% Verified Answers

Hemodynamic monitoring - A branch of physiology that deals with the circulation of the blood -Heme = blood -dynamic: physical force of energy; movement Study/movement of blood through the body End Diastolic Volume (EDV) - Heart is done filling before releasing -fills 2x as long as systole End Systolic Volume (ESV) - volume of blood remaining in each ventricle after systole Volume or Pressure? - Blood measured in volume -hemodynamics measured in pressure -volume DOES NOT equal pressure Hemodynamic pressures -volume of blood -space for the blood (volume influences pressure) Cardiac Output - The amount of blood ejected from the heart (LV) in one minute -normal values 4-8 L/min CO = HR x SV Cardiac Index - Tailors the CO to individual body size -normal value 2.5-4.0 L/min/m2 (2.0 = cardiogenic shock) Blood Pressure - 1. Cardiac output (how much blood is leaving heart) 2. peripheral blood vessels (what do they look like - size) Systolic BP / Diastolic BP Mean Arterial Pressure (MAP) - Most reliable measure of systemic and organ perfusion -MAP 65 mmHg considered adequate (organs are perfusing) MAP = (2 x DBP) + SBP / 3 Arterial Lines - Set up arterial line monitoring 1. Catheter 2. Pressure tubing 3. Pressure bag 4. Priming fluid (normal saline) 5. Transducer 6. Monitoring cable 7. Bedside monitor Measures every single pulse that goes through catheter -transducer sense pressure in blood and creates waves -*can inhibit proper flow to hand so be aware!* Abnormal Arterial Waveforms - Higher waves = higher BP Heart rate - Electrical activity stimulates myocardial cells -cardiac muscle contracts -increase pressure in the heart In between heart beats - diastole (filling) -lot of time between heart beats = more time for filling Stroke Volume (SV) - Amount of blood ejected from heart during ventricular systole (each contraction/beat) -normal values 60-100 ml/beat) Things that affect SV: 1. Preload 2. Afterload 3. Contractility Preload - Volume returning to the heart -volume in the ventricles waiting to be ejected *Volume creates pressure* Contractility - Force of contraction Starlings Law -dependent on amount of stretch and condition of the heart muscle -influenced by preload -causes cardiac cells to stretch -increases preload = harder it will snap (stronger contraction) -over time, not good to have lot of pre-load = cells start to tire Afterload - Resistance the heart must push against -dependent on arterial vessel status -don't want too much or too little -heart will tire sooner or not have enough to push through all blood Pulse Pressure (PP) - The difference between the systolic and diastolic BP -quick look at stroke volume (idea of what it is, not exact) Ex: BP = 140/80 - 140-80 = PP: 60 Significance: -decreasing the PP may precede decreases in diastolic BP in patients developing shock -decreasing PP is an early sign of hypovolemia Swan Ganz Catheter (SGC) - soft, flexible catheter that is inserted through a vein into pulmonary artery -used to provide continuous measurements of pulm artery pressure. can exercise with device but patient should avoid activities that increase pressure on injection site Complications of SGC - -Infection -ventricular dysrhythmias (dislodged & aggravates inside of heart in RV) -pulmonary infarction or artery rupture (too far in pulm. artery & inflate balloon can rupture - no blood going to lungs) Nurses can't inflate balloon at bedside (considered a central line)