Proper artery

When administering a drug into a vein by a venipuncture, tiie nurse should place a tourniquet above the selected vein. It is important to tighten the tourniquet so that venous blood flow is blocked but arterial blood flow is not. The nurse should allow the veins to fill (distend) and then should pull tiie skin taut (to anchor the vein and the skin) and insert tiie needle into tiie vein, bevel up, and at a short angle to tiie skin. Blood should immediately flow into the syringe if tiie needle is properly inserted into the vein. 

To properly calculate the extent of a shunt, however, requires the patient to breathe 100% oxygen for 15-20 minutes. Table III illustrates that the low P 02 in hypoventilation, diffusion defect, and V/Q inequality is corrected by breathing 100% oxygen whereas in a true veno-arterial shunt it is not. 

Every patient with a suspected acid-base disturbance should have an arterial blood gas and a serum chemistry panel drawn concurrently. The results of these tests should be reviewed using a systematic approach to ensure proper interpretation. 

PROMETHAZINE HYDROCHLORIDE The preferred parenteral route of administration is deep IM injection properly administered IV doses are well tolerated, but this method is associated with increased hazard. IV administration should not exceed 25 mg/mL at a rate no more than 25 mg/min. Avoid subcutaneous and intra-arterial injection. Use contraindicated in patients younger than 2 years of age. 

Field tourniquets must be capable of reliably applying enough pressure to occlude arterial bleeding. If a tourniquet applies enough pressure to stop only the venous flow, then the rate of blood loss from an arterial wound will most likely increase. It should be noted that some small blood seepage may continue in the case of traumatic amputation due to medullar blood flow even with a properly tightened tourniquet. 

When most people think about the arteries at all, it s in terms of plumbing. The arteries are simply pipes, conduits, for blood flow. Problems occur when those pipes get clogged, although not in the simplistic way that s commonly imagined. The plaque, as arterial blockage is properly termed, doesn t accumulate on the inner walls of the arteries the way calcium builds up on bathroom plumbing. Rather, it s a complex process that develops inside the layers of the walls of those arteries. 

In the porta hepatis, the proper hepatic artery divides into the right branch (from which the cystic artery emerges) and the left branch (from which a middle hepatic artery occasionally emerges). The branches of the hepatic artery run close to the portal veins and may even (rarely) coil round them in places. An arterial sphincter is located prior to the further division of the hepatic artery into smaller branches. There are anastomoses between the arterial branches and the hepatic vein. By way of an arteriolar sphincter (46), the interlobular arteries branch into intralobular arterioles, supplying the lobules of the liver with arterial blood. The arterial blood enters the sinusoids either through terminal branches or through arterioportal anastomoses and mixes with the portal blood. The pressure in the hepatic arterioles is 30-40 mm Hg. (36, 46, 61)... 

As an alternative to percutaneous injection therapy, there is a possibility to develop new local-interventional treatment strategies by selectively exploring the tumourfeeding branch of the proper hepatic artery. 

There are three distinct types of muscle tissue in vertebrates striated, smooth, and cardiac. Striated, or skeletal, muscle is attached, at least at one end, to the skeleton via tendons. This muscle type is often referred to as the voluntary muscle, as it can be consciously controlled. Smooth muscle is usually arranged in sheets or layers in tubular systems, such as arteries and veins (see Blood Vessels), the gastrointestinal and respiratory tracts, and the genitourinary tracts. The activities of the smooth muscles are not under conscious control rather they are coordinated by the autonomic (involuntary) nervous system. The cardiac muscle comprises the bulk of the heart wall proper and small amounts are found in the superior vena cava and pulmonary vein. The cardiac muscle is not under conscious control it has an automaticity center which responds to the autonomic nervous system when needed (see section Impulse Conduction). In the heart, cardiac muscle cells are joined in a network of fibers and are connected by gap junctions, which facilitate the conduction of electrical impulses through the cardiac muscle network. In addition to the typical cardiac myocytes, there are other cardiac muscle cells that are specialized to initiate, attenuate, or accelerate the electrical impulses for coordinated contraction of the cardiac network. 

Arterial puncture requires considerable skiE and is usuaEy performed only by physicians or speciaEy trained technicians or nurses. The preferred sites of arterial puncture are, in order, the (1) radial artery at the wrist, (2) brachial artery in the elbow, and (3) femoral artery in the groin. Because leakage of blood from the femoral artery tends to be greater, especially in the elderly, sites in the arm are most often used. The proper technique for arterial puncture is described in NCCLS Standard Hll-A3. ... 

When blood is collected from a central venous catheter or arterial line, it is necessary to ensure that the composition of the specimen is not affected by the fluid that is infused into the patient. The fluid is shut off using the stopcock on the catheter, and lOmL of blood is aspirated through the stopcock and discarded before the specimen for analysis is withdrawn. Blood properly collected from a central venous catheter and compared with blood drawn from a peripheral vein at the same time shows notable differences in composition. A comparison of arterial blood with central and peripheral venous blood is illustrated in Table 2-5. 

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