Chemistry Assignment



Chemistry Assignment

Question 1: Identify the role of regulatory mechanisms in the maintenance of fluid balance

Principles of Fluid and Electrolyte Balance

Homeostatic mechanisms respond to changes in composition of the ECF.

There are no receptors that can directly monitor fluid and electrolyte balance.

Cells cannot move water by active transport.

The content of fluids and electrolytes in the body is a balance between dietary absorption and urinary loss.

Fluid Balance

Composition of ICF is substantially different than that of ECF: due to selective permeability of the cell membranes.

Concentrations of molecules are dependent upon the transport processes and by electric charge differences across the cell membrane.

Water movement across the cell membrane is controlled by…? osmosis

Thus, net movement of water (fluid shift) is affected by changes in concentrations of solutes in ICF and ECF (Schierhout & Roberts, 1999).

Question 2: Assess a client's fluid and electrolyte balance as reflected in laboratory results and nursing observations

A normal balance between the body's fluids and electrolytes, and acids and bases, must exist for a person to be healthy. Homeostasis, the dynamic process by which the body constantly adjusts to internal and external stimuli, is disrupted by abnormalities of fluid levels and electrolyte content. The body constantly uses feedback mechanisms to maintain fluid and electrolyte balance. The nervous and endocrine systems are most intimately involved in feedback. The integumentary, respiratory, digestive, and urinary systems also respond to feedback mechanisms (Noblett et al. 2006).

Any disorder, disease, or injury can disrupt homeostasis. The risk of serious disturbances in fluid-electrolyte or acid-base balance increases in clients at the extremes of the age spectrum, in those with burn injuries, and in those with pre-existing conditions or chronic illnesses. Nurses play a major role in monitoring clients for actual or potential threats to homeostasis, with nursing care being directed toward monitoring and maintaining this balance. This topic continues the discussion of fluids and the major electrolytes. Emphasis is given to data collection and nursing concerns related to excesses or deficiencies of fluids and electrolytes.

Diagnostic Tests

Many laboratory tests are aimed at evaluating the body's fluid and electrolyte or acid/base balance. Chemical studies of electrolytes are probably among the most commonly ordered laboratory studies. The healthcare provider may order the determination of levels of a single electrolyte or a combination of electrolytes. In general, a basic (BMP) or a comprehensive metabolic panel (CMP) consists of laboratory testing of specific numbers of certain important chemicals found in blood plasma. Most clinical facilities have standard panels identified with terms such as “BMP 6,” “BMP 8,” or “CMP 24.” Each facility defines the components of these chemistry panels. The fundamental chemistry panel consists of the basic electrolytes (sodium, potassium, and chloride) plus glucose. Normal chemistry and hematology laboratory values are given in tables on Point.

Other commonly ordered tests include hematologic tests of the complete blood count (CBC), clotting factors, and liver function tests (LFTs). In addition, arterial blood gas (ABG) evaluations may be performed to determine the pH (potential of hydrogen in concentration) of blood, a valuable indicator of acidosis or ...