Laboratory and diagnostic testing. The words themselves often conjure up cold and impersonal images of needles, specimens lined up in collection containers, and high-tech electronic equipment. But they do not stand alone. They are tied to, bound with, and tell of health or disease in the blood and tissue of the individual. Laboratory and diagnostic studies augment the health-care provider’s assessment of the quality of an individual’s physical being. Test results guide the plans and interventions geared toward strengthening life’s quality and endurance. Beyond the pounding noise of the magnetic resonance imaging machine, the cold steel of the x-ray table, the sting of the needle, the invasive collection of fluids and tissue, and the probing and inspection is the gathering of evidence that supports the health-care provider’s ability to discern the course of a disease and the progression of its treatment. Laboratory and diagnostic data must be viewed with thought and compassion, however, as well as with microscopes and machines. We must remember that behind the specimen and test result is the person from whom it came, a person who is someone’s son, daughter, mother, father, husband, wife, or friend.

This book is written to help health-care providers in their understanding and interpretation of laboratory and diagnostic procedures and their outcomes. Just as important, it is dedicated to all health-care professionals who experience the wonders in the science of laboratory and diagnostic testing, performed and interpreted in a caring and efficient manner.

The authors continue to enhance and update four main areas in this new edition: organization of the content, pathophysiology that affects test results, patient safety, and patient/family education with expected patient outcomes.

Organization of the content: Time is a precious commodity. The content in the 11th edition puts the “need to know” information at the top of each study, in the order we imagine readers might prioritize what they need to know. Also, closely related studies are combined under a single title to maintain a smaller book size without affecting the number of studies included in the book. A new feature in the 11th edition is the identification of a subset of Core Laboratory (Core Lab) and Core Diagnostic (Core Dx) studies designated by orange-shaded tabs above the study name . The authors hope that by identifying these core studies, students will have a place to begin—first learning about the tests they will encounter most often. These studies are also listed in the index under the alphabetical entries “Core Lab Studies” and “Core Diagnostic Studies.” References to related studies throughout the manual will help readers integrate laboratory and diagnostic test results into safe, compassionate, and effective nursing care as they become involved in investigating the bigger picture. Portability is another important feature of a comprehensive reference book. To that end, repetitive content from the individual studies has been consolidated in Laboratory/Diagnostic Procedural Checklist for Students and Appendix A: Patient Preparation and Specimen Collection.

There are six appendices associated with this 11th edition that address important topics related to patient/family education and expected patient outcomes:

• Appendix A: Patient Preparation and Specimen Collection—print edition
• Appendix B: Laboratory Critical Findings—print edition A table summarizing commonly reported laboratory critical findings. Timely notification to the requesting health-care provider (HCP)of any critical findings and related symptoms is a role expectation of the professional nurse. A listing of these findings varies among facilities.
• Appendix C: Diagnostic Critical Findings—print edition A table summarizing commonly reported diagnostic critical findings. Timely notification to the requesting health-care provider (HCP)of any critical findings and related symptoms is a role expectation of the professional nurse. A listing of these findings varies among facilities.
• Appendix D: Skin Assessment for Infection, Hematoma, and Pressure Damage—on FADavis.com The skin assessment appendix outlines the ways that laboratory procedures (specimen procurement) and diagnostic procedures (patient positioning) can cause skin complications. Appendix D also describes the studies used to predict risk for, identify, or monitor therapy administered for skin complications.
• Appendix E: Current Trends in Health Care—on FADavis.com Nurses should be informed regarding potential and newly developed technology; they or their patients may be introduced to these technologies in the course of their health care. Examples of approved and developing applications of technology specific to health care are presented in this appendix.
• Appendix F: The Human Microbiome: Patient Care Considerations for Nurses—on FADavis.com The microbiome appendix is intended to provide some basic information regarding the human microbiome, how it affects our health, and potential nursing implications. The content also offers a review of terminology regarding genetics and molecular test methods used to gather genetic information. Last, the microbiome appendix highlights the nurse’s unique and significant role in antimicrobial stewardship programs.

Pathophysiology that affects test results: The Potential Diagnosis section includes explanations of increased or decreased laboratory values to assist in associating pathophysiology with study findings. The authors present a range of age-specific reference normal laboratory values for the neonatal, pediatric, adult, and older adult populations. It should be mentioned that standardized information for the complexity of neonatal, pediatric, and older adult populations is difficult to document. Studies to establish normal ranges for neonates and pediatric patients are limited in number—it is understandable that parents would be reluctant to have their children participate in such studies, especially those involving blood tests. Neonates and pediatric patients are not “little adults,” as has so often been said. Their organ systems are not fully developed and continue to mature over time, which can change the definition of a “normal” finding, incrementally, over time. Evaluating laboratory findings in older adults is also a challenging task. Older adults often have complex health situations. Laboratory values may be increased or decreased in older adults due to the sole or combined effects of malnutrition, alcohol use, medications, and the presence of multiple chronic or acute diseases with or without muted symptoms. It is believed that changes in older adult laboratory findings occur in waves at certain points as we advance in age, rather than in steady increments over time.

Patient safety: The authors appreciate that nurses are the strongest patient advocates with a huge responsibility to protect the safety of their patients. We have also observed student nurses in clinical settings being interviewed by facility accreditation inspectors, so we have updated reminders for a variety of safety topics. Examples include information related to positive patient identification; hand-off communication of critical information; proper timing of diagnostic procedures; rescheduling of specimen collection for therapeutic drug monitoring; use of evidence-based practices for prevention of surgical site infections; descriptions of study-related complications and how to avoid them; adverse drug reactions and how to avoid them; the nurse’s role in the process of obtaining an informed written patient consent before providing care, treatment, or services; information regarding the move to track or limit exposure to radiation from imaging studies for adults; and the Image Gently campaign for pediatric patients who undergo diagnostic studies that utilize radiation.

Patient/family education with expected patient outcomes: The fourth area of emphasis coaches the nurse in providing patient education and provides examples for the nurse to anticipate and respond to a patient’s questions or concerns. Elements of this area include the following:

• Describing the purpose of the procedure
• Understanding study-specific patient preparation
• Addressing concerns about pain
• Understanding potential nursing problems in conjunction with the implications of the test results
• Providing potential treatment considerations with related patient/family education
• Describing postprocedural care and expected patient outcomes
• Summing up with a Clinical Judgment statement that embraces critical thinking and clinical reasoning to help students/instructors/nurses focus on patient management and related teaching/learning needs

Related websites for patient education are included throughout the book to provide additional educational resources for the patient and the nurse.

Laboratory and diagnostic studies are essential components of a complete patient assessment. Examined in conjunction with an individual’s history and physical examination, laboratory studies and diagnostic data provide clues about health status. Nurses are increasingly expected to integrate an understanding of laboratory and diagnostic procedures and expected outcomes in assessment, planning, implementation, and evaluation of nursing care. The data help develop and support nursing diagnoses, interventions, and outcomes.

Nurses may interface with laboratory and diagnostic testing on several levels, including the following:

• Interacting with patients and families of patients undergoing diagnostic tests or procedures, and providing pretest, intratest, and posttest information and support
• Maintaining quality control to prevent or eliminate problems that may interfere with the accuracy and reliability of test results
• Providing education and emotional support at the point of care
• Ensuring completion of testing in a timely and accurate manner
• Collaborating with other health-care professionals in interpreting findings as they relate to planning and implementing total patient care
• Communicating significant alterations in test outcomes to appropriate health-care team members
• Coordinating interdisciplinary efforts

Whether the nurse’s role at each level is direct or indirect, the underlying responsibility to the patient, family, and community remains the same.

The authors hope that the changes and additions made to the book will reward users with an expanded understanding of and appreciation for the place laboratory and diagnostic testing holds in the provision of high-quality nursing care and will make it easy for instructors to integrate this important content in their curricula. The authors would like to thank all the users of the previous editions for helping us identify what they like about this book as well as what might improve its value to them. We want to continue this dialogue. As authors, it is our desire to capture the interest of our readers, to provide essential information, and to continue to improve the presentation of the material in the book and ancillary products. We encourage our readers to provide feedback to the F.A. Davis website and to the publisher’s sales professionals. Your feedback helps us modify the material—to change with your changing needs.

ASSUMPTIONS

• The authors recognize that preferences for the use of specific medical terminology may vary by institution. Much of the terminology used in this Handbook is sourced from Taber’s Cyclopedic Medical Dictionary.
• The definition, implementation, and interpretation of national guidelines for the treatment of various medical conditions changes as new information and new technology emerge. The publication of updated information may at times be contentious among the professional institutions that offer either support or dissent for the proposed changes. This can cause confusion when a patient asks questions about how their condition will be identified and managed. The authors believe that the most important discussion about health care occurs between the patient and the patient’s health-care provider(s). Although the individual studies may point out various screening tests used to identify a disease, the authors often refer the reader to websites maintained by nationally recognized authorities on specific topics that reflect the most current information and recommendations for screening, diagnosis, and treatment.
• Most institutions have established policies, protocols, and interdisciplinary teams that provide for efficient and effective patient care within the appropriate scope of practice. It is not our intention that the actual duties a nurse may perform be misunderstood by way of misinterpreted inferences in writing style, but the information prepared by the authors considers that specific limitations are understood by the licensed professionals and other team members involved in patient care activities and that the desired outcomes are achieved by order of the appropriate health-care provider.