Crystalloids

A diffusion mechanism is also used in dialysis as a means of separating colloids from crystalloids. The rate of diffusion of molecules in gels is practically the same as in water, indicating the continuous nature of the aqueous phase. The diffusion of gases into a stream of vapour is of considerable importance in diffusion pumps. 

Ringer s lactate, in which lactate is added to Ringer s solution, is probably the most popular crystalloid (salt) solution for intravenous use in humans. The lactate is gradually converted to sodium bicarbonate within the body so that an uncompensated alkalosis is prevented (13). These crystalloid solutions cannot support life without red cells saline passes rather quickly into the tissue spaces of various organs (14), especially the Hver (15). 

Introduce an intravenous catheter and apply volume (crystalloid solutions like saline or Ringer s)... 

Volume replacement is crucial in antianaphylactic treatment. It should be started with crystalloid solution (saline or Ringer s solution). However, in severe shock, higher... 

The principal factors which affect the breaking temperature are type of salad oil (cottonseed, corn, soybean, or other), proportion of oil, proportion of total moisture, and proportion of yolk. To a much lesser degree, the breaking temperature is also influenced by the mean particle size of the dispersed oil and the concentration of crystalloids in the water. 

A phenomenon far more intricate than just conventional freezing points is demonstrable, by a consideration of two mayonnaise formulations, identical as to crystalloid content and with the following composition ... 

Notwithstanding the fact that the crystalloids present are dissolved in the case of mayonnaise 2 in some 28% more water than for mayonnaise 1, the breaking temperature of mayonnaise 2 is some 12° F. lower than that of mayonnaise 1. Obviously, were it simply a matter of freezing point lowering, the difference would have to be in the reverse direction. 

Galinanes, M., Qiu, Y., Ezrin, A. and Hearse, D. (1992). PEG-SOD and myocardial protection. Studies in the blood- and crystalloid-perfused rabbit and rat hearts. Circulation 86, 672-682. 

Rapid fluid resuscitation with a crystalloid or a colloid if hypotensive (large volumes may be required)... 

Crystalloid/colloid to achieve a pulmonary capillary wedge pressure (PCWP) between 15 and 18 mmHg... 

Use a crystalloid (normal saline or lactated Ringer s solution) or a colloid (hydroxyethyl starch or albumin 5%) intravenous boluses... 

The optimal infusion rate is dependent on the clinical status of the patient and choice of crystalloid... 

Compare and contrast the relative advantages and disadvantages of crystalloids, colloids, and blood products in the treatment of hypovolemic shock. 

Three major therapeutic options are available to clinicians for restoring circulating blood volume crystalloids (electrolyte-based solutions), colloids (large-molecular-weight solutions), and blood products. 

In the absence of ongoing blood loss, administration of 2000 to 4000 mL of isotonic crystalloid will normally re-establish baseline vital signs in adult hypovolemic shock patients. 

The volume of colloid administered is primarily confined to the intravascular space, in contrast to isotonic crystalloid solutions that distribute throughout the extracellular fluid space. 

Side effects from crystalloids primarily involve fluid overload and electrolyte disturbances of sodium, potassium, and chloride.23 Dilution of coagulation factors can also occur resulting in a dilutional coagulopathy.24 Two clinically significant reasons LR is different from NS is that LR contains potassium and has a lower sodium content (130 versus 154 mEq/L or mmol/L). Thus, LR has a greater potential than NS to cause... 

Generally, the major adverse effects associated with colloids are fluid overload, dilutional coagulopathy, and anaphy-lactoid/anaphylactic reactions.24,32 Although derived from pooled human plasma, there is no risk of disease transmission from commercially available albumin or PPF products since they are heated and sterilized by ultrafiltration prior to distribution.24 Because of direct effects on the coagulation system with the hydroxyethyl starch and dextran products, they should be used cautiously in hemorrhagic shock patients. This is another reason why crystalloids maybe preferred in hemorrhagic shock. Furthermore, hetastarch can result in an increase in amylase not associated with pancreatitis. As such, the adverse-effect profiles of the various fluid types should also be considered when selecting a resuscitation fluid. 

Is there a detectable blood pressure If yes, obtain history, perform physical examination, obtain blood for baseline laboratory tests, and monitor ECG. If not, begin isotonic crystalloid fluid resuscitation immediately (see step 4 below). 

Has the goal arterial blood pressure been achieved If not, give additional fluid therapy hourly blending crystalloids and isooncotic colloids based on inadequate blood pressure response. 

Therapeutic fluids include crystalloid and colloid solutions. The most commonly used crystalloids include normal saline, hypertonic saline, and lactated Ringer s solution. Examples of colloids include albumin, the dextrans, hetastarch, and fresh frozen plasma. 

Therapeutic intravenous (TV) fluids include crystalloid solutions, colloidal solutions, and oxygen-carrying resuscitation solutions. Crystalloids are composed of water and electrolytes, all of which pass freely through semipermeable membranes and remain in the intravascular space for shorter periods of time. As such, these solutions are very useful for correcting electrolyte imbalances but result in smaller hemodynamic changes for a given unit of volume. 

Half-normal saline is a hypotonic fluid that provides free water in relative excess when compared to the sodium concentration. This crystalloid is typically used to treat patients... 

TABLE 24-3. Electrolyte and Dextrose Content of Selected Crystalloid Fluids... 

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