Infusion types

FIGURE 60-1. The route of parenteral nutrition (PN) and the infusion type depend on the patient s clinical status and the expected length of therapy. 

Table 3.8 PTP Surgical Study enrollment by surgery and infusion types [30]...

The two primary types of plastics, thermosets and thermoplastics, are made almost exclusively from hydrocarbon feedstocks. Thermosetting materials are those that harden during processing (usually during heating, as the name implies) such that in their final state they are substantially infusible and insoluble. Thermoplastics may be softened repeatedly by heat, and hardened again by cooling. 

Hexamethylenetetramine. Hexa, a complex molecule with an adamantane-type stmcture, is prepared from formaldehyde and ammonia, and can be considered a latent source of formaldehyde. When used either as a catalyst or a curative, hexa contributes formaldehyde-residue-type units as well as benzylamines. Hexa [100-97-0] is an infusible powder that decomposes and sublimes above 275°C. It is highly soluble in water, up to ca 45 wt % with a small negative temperature solubiUty coefficient. The aqueous solutions are mildly alkaline at pH 8—8.5 and reasonably stable to reverse hydrolysis. 

Fibers. The principal type of phenoHc fiber is the novoloid fiber (98). The term novoloid designates a content of at least 85 wt % of a cross-linked novolak. Novoloid fibers are sold under the trademark Kynol, and Nippon Kynol and American Kynol are exclusive Hcensees. Novoloid fibers are made by acid-cataly2ed cross-linking of melt-spun novolak resin to form a fuUy cross-linked amorphous network. The fibers are infusible and insoluble, and possess physical and chemical properties that distinguish them from other fibers. AppHcations include a variety of flame- and chemical-resistant textiles and papers as weU as composites, gaskets, and friction materials. In addition, they are precursors for carbon fibers. 

Infusion Method. Infusion is a classic method for top-fermented beers and is used for ad British types. The whole mash is heated graduady from mashing-in to mashing-off with holding times for the degradation of protein and starch. No part of the mash is boiled and the malt, therefore, must be well-modified to assure the breakdown of ad soluble substances. Because no boiling takes place there is no physical breakdown of the malt, and consequentiy infusion is not as effective as decoction despite the better protection of the enzymes. 

Several clinical trials have been conducted with streptokinase adrninistered either intravenously or by direct infusion into a catheterized coronary artery. The results from 33 randomized trials conducted between 1959 and 1984 have been examined (75), and show a significant decrease in mortaUty rate (15.4%) in enzyme-treated patients vs matched controls (19.2%). These results correlate well with an ItaUan study encompassing 11,806 patients (76), in which the overall reduction in mortaUty was 19% in the streptokinase-treated group, ie, 1.5 million units adrninistered intravenously, compared with placebo-treated controls. The trial also shows that a delay in the initiation of treatment over six hours after the onset of symptoms nullifies any benefit from this type of thrombolytic therapy. Conversely, patients treated within one hour from the onset of symptoms had a remarkable decrease in mortaUty (47%). The benefits of streptokinase therapy, especially in the latter group of patients, was stiU evident in a one-year foUow-up (77). In addition to reducing mortahty rate, there was an improvement in left ventricular function and a reduction in the size of infarction. Thus early treatment with streptokinase is essential. 

To allow the IV fluid to infuse over a specified period, the IV flow rate must be determined. Before using one of the methods below, the drop factor must be known. Drip chambers on the various types of IV fluid administration sets vary. Some deliver 15 drops/mL and others deliver more or less than this number. This is called the drop factor. The drop factor (number of drops/mL) is given on the package containing the drip chamber and IV tubing. Three methods for determining the IV infusion rate follow. Methods 1 and 2 can be used when the known factors are the total amount of solution, the drop factor, and the number of hours over which the solution is to be infused. 

Before starting an IV infusion of oxytocin for the induction of labor, the nurse obtains an obstetric history (parity, gravidity, previous obstetric problems, type of labor, stillbirths, abortions, live birth infant abnormalities)... 

When oxytocin is prescribed, the primary health care provider orders the type and amount of IV fluid, the number of units of oxytocin added to the IV solution, and the IV infusion rate An electronic infusion device is used to control the infusion rate. The primary health care provider establishes guidelines for the administration of the oxytocin solution and for increasing or decreasing the flow rate or discontinuing the administration of oxytocin based on standards established by the Association of Women s Health, Obstetric, and Neonatal Nurses (AWHONN). Usually, the flow rate is increased every 20 to 30 minutes, but this may vary according to the patient s response. The strength, frequency, and duration of contractions and the FHR are monitored closely. 

The primary health care provider orders the dose of tiie potassium salt (in mEq) and the amount and type of IV solution, as well as the time interval during which tiie solution is to be infused. After the drug is added to tiie IV container, tiie container is gently rotated to ensure mixture of tiie solution. A large vein is used for administration tiie veins on tiie back of tiie hand should be avoided. An IV containing potassium should infuse in no less than 3 to 4 hours. This necessitates frequent monitoring of the IV infusion rate, even when an IV infusion pump is used. 

Some types of injections must be made iso-osmotic with blood serum. This applies particularly to large-volume intravenous infusions if at all possible hypotonic solutions cause lysis of red blood corpuscles and thus must not be used for this purpose. Conversely, hypertonic solutions can be employed these induce shrinkage, but not lysis, of red cells which recover their shape later. Intraspinal injections must also be isotonic, and to reduce pain at the site of injection so should intramuscular and subcutaneous injections. Adjustment to isotonicity can be determined by the following methods. 

A summary of the properties of the different types of dextrans available is presented in Table 25.1. Dextrans for clinical use as plasma expanders must have moleeular weights between 40000 (= 220 glucose units) and 300000. Polymers below the minimum are excreted too rapidly fiom the kidneys, whilst those above the maximum are potentially dangerous because of retention in the body. In practice, infusions containing dextrans of average molecular weights of40000,70000 and 110000 are commonly encountered. 

In order to account for the nonvolatility, infusibility, and limited solubility, Leuchs postulated polymerization of the ground type cyclic compound, as indicated by the subscript x in his formula given above. It is now well established that linear polypeptides are produced on decarboxylation of the N-carboxyanhydrides of a-amino acids, and under favorable conditions the chain length may be fairly large. Leuchs favored the view that strained rings, i.e., those of other than five or six... 

In the previous discussion of the one- and two-compartment models we have loaded the system with a single-dose D at time zero, and subsequently we observed its transient response until a steady state was reached. It has been shown that an analysis of the response in the central plasma compartment allows to estimate the transfer constants of the system. Once the transfer constants have been established, it is possible to study the behaviour of the model with different types of input functions. The case when the input is delivered at a constant rate during a certain time interval is of special importance. It applies when a drug is delivered by continuous intravenous infusion. We assume that an amount Z) of a drug is delivered during the time of infusion x at a constant rate (Fig. 39.10). The first part of the mass balance differential equation for this one-compartment open system, for times t between 0 and x, is given by ... 

CMV IgG and polyvalent IVIG The maximum recommended total dosage per infusion is 150 mg/kg beginning within 72 hours of transplantation Follow-up doses and time intervals depend on the type or organ transplanted Stomach upset (1 -6%) Fevers and chills (1-6%) Flushing (1-6%)... 

Primary therapy is based on disease severity and type of hemorrhage.7 Most patients with mild to moderate disease and a minor bleeding episode can be treated with l-desamino-8-D-arginine vasopressin [desmopressin acetate (DDAVP)], a synthetic analog of the antidiuretic hormone vasopressin. DDAVP causes release of von Willebrand factor (vWF) and factor VIII from endogenous storage sites. This formulation increases plasma factor VIII levels by three- to fivefold within 30 minutes. The recommended dose is 0.3 mcg/kg intravenously (in 50 mL normal saline infused over 15 to 30 minutes) or subcutaneously or 300 meg intranasally via concentrated nasal spray every 12 hours. Peak effect with intranasal administration occurs 60 to 90 minutes after administration, which is somewhat later than with intravenous administration. Desmopressin infusion may be administered daily for up to 2 to 3 days. Tachyphylaxis, an attenuated response with repeated administration, may occur after several doses.8... 

Most patients with type 1 vWD (functionally normal vWF) and a minor bleeding episode can be treated successfully with desmopressin, which induces secretion of autologous factor VIII and vWF into plasma. The recommended dose is the same as that used to treat mild factor VIII deficiency (0.3 mcg/kg intravenously in 50 mL of normal saline infused over 15 to 30 minutes). This therapy generally is ineffective in type 2A patients who secrete qualitatively abnormal vWF and is controversial in type 2B patients because it may increase the risk of postinfusion thrombocytopenia. Type 3 vWD patients who lack releasable stores of vWF do not respond to DDAVP therapy.18... 

All monoclonal antibodies end in the suffix -mab. The syllable before -mab indicates the source of the monoclonal antibody (see Table 85-4). When administering an antibody for the first time, one should consider the source. The less humanized an antibody, the greater is the chance for the patient to have an allergic-type reaction to the antibody. The more humanized the antibody, the lower is the risk of a reaction. The severity of the reactions may range from fever and chills to life-threatening allergic reactions (which have resulted in death). Premedication with acetaminophen and diphenhydramine is common before the first dose of any antibody. If a severe reaction occurs, the infusion should be stopped and the patient treated with antihistamines, corticosteroids, or other supportive measures. 

Dextrose Dextrose infusion rate should be -3 1 mg/kg per minute, should comprise -50-60% of total daily calories Since this patient has type 2 diabetes mellitus, consider a goal of -3 mg/kg per minute Provide remainder of total daily calories as dextrose Total daily goal calories = 1 800 kcal/day 1 800 kcal/day -528 kcal/day (from intravenous lipid emulsion) 1272 kcal/day -440 kcal/day (from amino acids) 832 kcal/day to make up with dextrose. 3.4 kcal/g Y 245 8 dextrose/daY If using a 70% stock dextrose solution 245 g x 100 mL. 70 g 245 g/day x 3.4 kcal/g = 833 kcal/day As a double-check, convert to mg/kg/minute 245 g dextrose/day x 1000 mg/1 g x 1 day/1440 minute = 1 70.1 mg/minute 170.1 mg/minute -2.8 mg/kg per minute... 

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