click below
click below
Normal Size Small Size show me how
SFCC A&R LP3
A&R LP3
Question | Answer |
---|---|
Blood pressure cuff | Non-invasive hemodynamic monitoring system we use on almost all patients each day, provides us with quantitative information concerning our patients, it reflects the pressure exerted on the wall of the arteries |
Systolic blood pressure | pressure of the blood in the arteries when the ventricles are contracted |
Diastolic blood pressure | pressure of the blood in the arteries when the ventricles are relaxed |
Hemodynamic | the forces which circulate blood through the body - it describes the intravascular pressure and flow that occurs when the heart muscle contracts and pumps blood throughout the body |
Hemodynamic monitoring | measures vascular capacities, blood volume, pump effectiveness, and tissue perfusion |
Invasive monitoring | performed on the seriously ill patient because it is a more accurate measurement of blood pressure, heart function, and volume status. It measures the minute to minute pressure and flow variations that occur within and between compartments. |
Intravascular volume | the amount of fluid circulating in the vasculature (affected by dehydration, diuresis, and volume overload due to heart or kidney failure) |
Inotropy | strength of myocardial contractions. Myocytes are the only muscle cells which are able to vary the strength of contraction. It can be affected by exercise, stress, pharmaceutical agents which increase the strength of myocardial contractions |
Vasoactivity | the expanding and contracting of blood vessels to accommodate the variations in blood flow, regulate arterial pressure, and meet metabolic demands of organs and tissues. |
Hormones that affect vasoactivity | Angiotensin II, epinephrine, norepinephrine, and vasopression |
Chronotropy | involves the timing or rate of heart contraction. This component affects tissue perfusion and is not considered a hemodynamic component. However, all four need to function normally for patients system to remain stable. |
Afterload | describes the resistance that the heart has to overcome during every beat to send blood into the aorta. The resistive forces include vasoactivity and blood viscosity. |
Cardiac Index (CI) | the amount of blood pumped by the heart per minute, per meter square of body surface area |
Cardiac Output (CO) | the volume of blood pumped by the heart in one minute. Normal 4-8 L/min |
Central venous pressure (CVP) | readings are used to approximate the right ventricular end diastolic pressure. The right ventricular end diastolic pressure assesses right ventricular flow and general fluid status. Most like the monitor used to closely watch fluid volume status. |
Low CVP | reflects hypovolemia or decreased venous return |
High CVP | reflects overhydration, increased venous return or right sided cardiac failure |
Mean Arterial Pressure (MAP) | reflects changes in the relationship between CO and SVR, reflects the arterial pressure in the vessels perfusing the organs (specifically the heart, brain, kidneys) |
MAP equation | 1 systolic plus 2 diastolic divided by 3 |
Low MAP | indicates decreased flow to organs |
High MAP | indicates increased cardiac workload |
Preload | occurs during diastole, it is the combination of pulmonary blood filling the atria and the stretching of myocardial fibers. Preload is regulated by variability in intravascular volume. |
Causes of reduced Preload | sepsis, hypovolemia, and vasodilator meds (nitrates) |
Volume reduction | decreased preload |
Volume increase | increased preload, mean arterial pressure, and stroke index |
Pulmonary artery pressure | (PAP) blood pressure in the pulmonary artery |
Increased pulmonary artery pressure | may indicate a left to right cardiac shunt, pulmonary artery hypertension, COPD, emphysema, pulmonary embolus (PE), pulmonary edema, left ventricular failure |
Pulmonary Capillary Wedge Pressure (PCWP or PAWP) | used to approximate the left ventricular end diastolic pressure (LVEDP) left ventricular end diastolic pressure |
High PCWP | may indicate left ventricular failure, mitral valve pathology, cardiac insufficiency, cardiac compression post hemorrhage |
Pulmonary vascular resistance (PVR) | the resistance or impediment of the pulmonary vascular bed to blood flow |
Increased PVR | caused by pulmonary vascular disease, pulmonary embolism, or pulmonary vasculitis or hypoxia |
Right ventricular pressure (RVP) | direct measurement that indicates right ventricular function and general fluid status |
High RVP | may indicate pulmonary hypertension, right ventricle failure, congestive heart failure |
Stroke index or Stroke volume index (SI or SVI) | the amount of blood ejected from the heart in one cardiac cycle relative to body surface area |
Increased SVI | may indicate septic shock, hyperthermia, hypervolemia or be caused by medications such as dopamine, dobutamine, or digitalis |
Stroke volume (SV) | the amount of blood pumped by the heart per cardiac cycle, it is measured in ml/beat |
Decreased stroke volume | may indicate impaired cardiac contractility or valve dysfunction and may result in heart failure |
Increased stroke volume | may be caused by an increase in circulating volume or an increase in inotropy |
Systemic Vascular resistance (SVR) | the measurement of resistance or impediment of the systemic vascular bed to blood flow |
Increased SVR (systemic vascular resistance) | can be caused by vasoconstrictors, hypovolemia, or late septic shock |
Decreased SVR (systemic vascular resistance) | can be caused by early septic shock, vasodilatros, morphine, nitrates, or hypercarbia. May require medications such as Dopamine or Levophed to support your patients system. |
Systolic BP normal value | 90-140 mmHg |
Diastolic BP normal value | 60-90 mmHg |
Mean arterial pressure (MAP)normal value | 70-100 mmHg |
Cardiac index (CI)normal value | 2.5 - 4 L/min/m2 very low may indicate shock |
Cardiac Output (CO) normal value | 4-8 L/min |
Central venous pressure (CVP) also known as right atrial pressure (RA) normal value | 2-6 mmHg |
Pulmonary artery pressure (PA) normal value | Systolic 20-30 mmHg Diastolic 8-12 mmHg Mean 25 mmHg |
Pulonary Capillary Wedge Pressure (PWCP) normal value | 4-12 mmHg |
Pulmonary vascular resistance (PVR) | 37-250 dynes/sec/cm5 Some list 10-250 |
Right ventricular pressure (RV) | Systolic 20-30 mmHg Diastolic 0-5 mmHg |
Stroke volume (SV) | 50-100 mL |
Systemic vascular resistance (SVR) | 800-1200 dynes/sec/cm5 |
Intra-arterial catheters (art lines) | offer a low risk and reliable method to continuously monitor systemic blood pressure. Critically ill pts with unstable CP status benefit from continuous monitoring. A second benefit is the ability to do serial blood sampling and ABG monitoring |
Increased cardiac output | Increased CO may indicate high circulating volume |
Decreased cardiac output | decreased CO may indicate decrease in circulating volume or decrease in the strength of ventricular contractions |