MAPCAs arise from the aorta or its large branches and supply blood to the pulmonary arteries, because of blockade of the main pulmonary arteries. In cases where patient is deeply cyanotic the size of the oxygenator and tubing size is selected keeping in mind the requirement of higher degree of hemodilution and higher requirement of arterial blood flows because of the presence of large (or major) aorto-pulmonary collaterals (MAPCA’s). Following are the tables showing the volume required to de-air various oxygenators, arterial filters and tubing.ĬPB CIRCUIT AND TOTAL PRIMING VOLUME WITH VARIOUS WEIGHT The total priming volume is determined by the hardware selected for the circuit to be employed. It is a standard practice to use a non blood CPB prime because of the benefits of hemodilution and concerns about blood borne diseases. To meet the need for the extra volume required to prime the CPB circuit as the patient’s blood volume is not sufficient enough to prime the CPB circuit.To check for any mistake in the assembling of the circuit.Generally the main objectives of priming are: Priming of the CPB circuit is an important task for the perfusionist. PRIMING VOLUME: the minimum amount of fluid (hemic or non hemic fluid) used to de- air the complete cardiopulmonary bypass (CPB) circuit is called priming volume or the circulating volume of CPB circuit. A recent radio nucleotide study called BVA (Blood Volume Analysis)-100, provides a measure of Red Blood Cells and Plasma with 98% accuracy. Blood volume (BV) can be calculated given the hematocrit (HCT the fraction of blood that is red blood cells) and plasma volume (PV):ĭiagnostic technologies are commercially available to measure human blood volume. A typical adult has a blood volume of approximately between 4.7 and 5 liters, with females generally having less blood volume than males. It is /.īlood volume is the volume of blood (both red blood cells and plasma) in the circulatory system of any individual. Recently, a weight-based formula was validated in the pediatric age group that does not include a square root, making it easier to use. A commonly used and simple one is the Mosteller formula:.The most widely used is the Du Bois formula:.It is difficult to actually measure the surface area of the human body so various calculations have been published to arrive at the BSA without direct measurement. Glucocorticoid dosing is also expressed in terms of BSA for calculating maintenance doses or to compare high dose use with maintenance requirement.Chemotherapy is often dosed according to the patient’s BSA.To calculate a better approximation of the required cardiac output as for example in children, cardiac index is used.To gain an appreciation of the true required glomerular filtration rate (GFR) renal clearance is usually divided by the BSA.Nevertheless, there have been several important critiques of the use of BSA in determining the dosage of medications with a narrow therapeutic index like many chemotherapy medications. For many clinical purposes BSA is a better indicator of metabolic mass than body weight because it is less affected by abnormal adipose mass. BSA is a measurement used in many medical tasks. It is used to calculate metabolic, electrolyte, nutritional requirements, drug dosage, and expected pulmonary function measurements. In physiology and medicine, the body surface area is the measured or calculated surface of human body. Namita Mishra, Sudha Rawat, Vishva Nath Sharmaīody surface area (BSA) is the area of the external surface of the body, expressed in square meters (m 2). Share this: Facebook Twitter Reddit LinkedIn WhatsAppĬalculation of Body Surface Area, Circulating Blood Volume, Requirement of Blood Products
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