Diagnostic

Laboratory tests and diagnostic procedures

The purpose of this section is to provide a comprehensive, concise, ready reference of practitioner ‘need-to-know’ information about laboratory tests and diagnostic procedures. Features of this section, in format order, include:

	•	Alphabetical list of laboratory tests and diagnostic procedures: This saves you time in looking up any test. You will also find combined laboratory profiles listed such as CBC, CMP, and Chemistry Profile.
	•	Norms are listed for all known age-groups and for all known units (i.e., national and international units). Also included are therapeutic peak and trough norms, toxic and panic levels, as well as associated signs, symptoms, and emergency treatment for overdose when applicable. Tests with toxic and/or panic levels include symptoms and treatment. Treatments listed are generally accepted treatments. The listing of these does not imply that some or all of them should be used. Selection of treatments must be based on the client's history and condition, as well as the history of the episode.
	•	Usage states the typical conditions or monitoring for which the diagnostic test or procedure is commonly used (i.e., cardiac catheterization).
	•	Increased, Decreased or Positive, Negative are categories to describe conditions that cause abnormal laboratory test results. Also listed, in alphabetical order, are medications and herbal and natural remedies that interfere with the laboratory results.
	•	Description: A concise description of the test or procedure is provided, including interpretation of results and significance for various conditions.
	•	Professional Considerations include seven types of information:    1.    Consent, risks, and contraindications: Indicate whether a separate special consent form IS or IS NOT required. Where tests or procedures carry significant risks, the risks that should be explained to the client are included in a highlighted alert box. Contraindications are in a list of generally accepted conditions (in a highlighted alert box labeled Risks) in which the test or procedure should not be performed and Relative Contraindications in which the test or procedure should be modified, where applicable.    2.    Preparation: Includes supplies needed, assessment for allergies, unusual scheduling requirements, procedural preparation requirements, such as establishing intravenous access, equipment/medications needed to treat anaphylaxis, and medicolegal handling.    3.    Procedure: Gives step-by-step description of specimen collection or procedural steps, including safety ‘time out’ for correct site or procedure verification, client positioning and participation, and monitoring required during the procedure. NOTE: For blood samples, mini-volumes (1 to 3 mL) are listed for tests in which special manual tests may be run on smaller volumes for clients in whom blood preservation is essential. For pediatric clients, microtainers may be used, but volumes should equate to those specified in the text (e.g., two 1-mL sized microtainers would be needed for a 2-mL specimen). For clients not at risk for iatrogenic anemia as a result of frequent blood sampling, the quickest turnaround times are achieved with higher volumes, which enable automated testing.    4.    Postprocedure care: Provides aftercare instructions regarding specimen handling, site dressing, activity restriction, vital signs, and postsedation monitoring.    5.    Client and family teaching: Includes instructions the client or family should be informed about, including precare, procedural care, aftercare, and monitoring, as well as disease-specific information, time frame for test results, and follow-up recommendations.    6.    Factors that affect results: Gives quality assurance information about items that will interfere with the accuracy of results, such as improper collection techniques, improper specimen handling, drugs and herbals that cause false-positive or false-negative results, and cross-reactivity of other diseases or conditions.    7.    Other data: Provides selected information from current research that may not yet be generalizable but could be helpful in decision-making for individuals or groups of clients; recommendations for confirmatory testing if the results are positive; direction to other tests related to the same diagnosis or condition and known association between tests; and national guideline information and recommendations, when available.