Volume, total blood

The average adult has about 16 g of sodium ions in her blood. Assuming a total blood volume of 5.0 L, what is the molarity of Na+ ions in blood ... 

This is approximately equal to the total blood volume in the body. Therefore, the entire blood volume is pumped by the heart each minute. 

Notes CO cardiac output VR venous return HR heart rate SV stroke volume EDV end-diastolic volume ESV end-systolic volume O blood flow AP pressure gradient R resistance r vessel radius P systolic pressure Piiastoik- diastolic pressure MAP mean arterial pressure TPR total peripheral resistance, P venous pressure Era- right atrial pressure Rv venous resistance. 

The fluid portion of the blood, the plasma, accounts for 55 to 60% of total blood volume and is about 90% water. The remaining 10% contains proteins (8%) and other substances (2%) including hormones, enzymes, nutrient molecules, gases, electrolytes, and excretory products. All of these substances are dissolved in the plasma (e.g., oxygen) or are colloidal materials (dispersed solute materials that do not precipitate out, e.g., proteins). The three major plasma proteins include ... 

The total blood flow to the kidneys is approximately 1200 ml/minute (equivalent to 750 ml of plasma) but this can increase to 1500 ml/minute if the renal blood vessels are fully dilated. This means that the entire blood volume passes through the kidneys in les than 5 min. Only the liver receives a greater total volume of blood per minute (1300 ml) but the larger mass (1.5 kg) of the liver means that the volume of blood reaching the kidneys per gram of tissue per minute is approximately five times greater than the liver ... 

Blood arriving at an organ of extraction normally contains only a fraction of the total drug present in the body. The flow through the major extraction organs, the liver and kidneys, is about 3 % of the total blood volume per minute, however, for many... 

The pharmacokinetic term clearance (CT) best describes the efficiency of the elimination process. Clearance by an elimination organ (e.g., liver, kidney) is defined as the volume of blood, serum, or plasma that is totally cleared of drug per unit time. This term is additive the total body or systemic clearance of a drug is equal to the sum of the clearances by individual eliminating organs. Usually this is represented as the sum of renal and hepatic clearances CT = CT renal -I- CL hepatic. Clearance is constant and independent of serum concentration for drugs that are eliminated by first-order processes, and therefore may be considered proportionally constant between the rate of drug elimination and serum concentration. 

Data summarized in Table 21.1 demonstrate that the level of luciferase gene expression increases with an increase in the volume of injected DNA solution. The maximal level of luciferase protein achieved was approximately 350 ng/mg of extracted protein from the liver. We also demonstrated in a previous study that the volume required for an optimal transfection varies with animal weight (Liu, F. et al., 1999). The volume for a maximal level of gene expression was approximately 1.2ml, 1.6ml or 3.0ml for animals with a body weight of 11—13g, 18-20 g or 30-33 g, respectively. The estimated volume for an optimal activity in mice is approximately 8-12% of animal weight, which is higher than total blood, estimated to be 7.3% of the body weight in mice (Wu et al., 1981). 

The lungs are covered extensively by a vast network of blood vessels, and almost all the blood in circulation flows through lungs. Deoxygenated blood is supplied to the lungs by the pulmonary artery. The pulmonary veins are similar to the arteries in branching, and their tissue structure is similar to that of systemic circulation. The total blood volume of the lungs is about 450 mL, which is about 10 percent of total-body blood volume.118... 

Diuretics work by increasing the amount of sodium and fluids excreted by the kidneys. Less fluid means less total blood volume and improved circulation and blood pressure. There are five main classes of the drug loop diuretics, thiazide diuretics, potassium-sparing diuretics, osmotic diuretics, and carbonic anhydrase inhibitors. 

Whole blood consists of water, cells, proteins, and electrolytes (Figure 3.15). Cells comprise approximately 45% of total blood volume. The noncellular components of blood are called plasma. Plasma is mostly water with some proteins (8% by weight). Plasma proteins may be divided into three categories serum albumin (60%) the a-, j8-, and -y-globuhns (36%) and fibrinogens (4%). Blood serum is the residual liquid left behind after whole blood is allowed to clot.5... 

Understanding Vd requires knowledge of the types of fluids into which a drug can distribute. A standard patient (70 kg, or 154 lbs) can be used to demonstrate key ideas. A 70-kg patient has approximately 5.0 L of blood. Because not every patient weighs 70 kg, blood volume is often expressed on a per mass basis as 0.071 L/kg (5 L/70 kg). Multiplication by patient mass gives that patient s approximate blood volume. Whole blood is 54% plasma by volume, so the amount of plasma in a 70-kg patient is 2.7 L. Other sources of fluid in the body include interstitial fluid and lymph ( 10 L) and intracellular fluids (—25 L). The total body water of a 70-kg male patient is approximately 38 L, or 55% of the body s mass. The value is closer to 50% for females. Total body volume for a 70-kg patient is around 70 L. 

Animal Species Total Blood Volume Available Volume When Blood Out (rounded mean) Maximum Safe Volume at One Bleeding Practicable Volume (mL) for Diagnostic Use from a Normal Adult... 

Hematologic Studies Hematologic study includes estimations of hemoglobin content, packed-cell volume, total erythrocytes, total leukocytes, platelets, or other measures of clotting potential. These should be performed on blood samples collected from all nonrodents, from 10 rats of both genders, from all groups at 3 months, 6 months, thereafter at approximately 6-month intervals, and at termination. If possible, these collections should be from the same rats of each interval. In additions, a pretest sample should be collected from nonrodents. 

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