Arterial Blood Gas and Acid-Base Physiology [antikvár]

Arterial blood gas and pH measurements, once confined to the research laboratory, are now used extensively in the management of patients who are acutely and chronically ill. In the care of individuals with pulmonary diseases, blood gas determinations are as important to diagnosis and treatment as is the electrocardiogram to the evaluation of patients with cardiac disorders or the blood sugar determination to monitoring diabetic patients. However, acid-base physiology and oxygen transport are inherently complex subjects. Unnecessary confusion often exists in the interpretation of blood gas and acid-base determinations; this confusion evolves in great degree from the application of the thermodynamic principles of gas behavior to the bedside management of critically ill patients. The ambiguous terminology that has developed in this field has impaired our understanding of this subject for over a century. In an attempt to simplify this historically complex subject, numbers and symbols are used routinely to communicate quantitative biologic measurements. Unfortunately, use of numerical values alone has led to the frequent misapplication of blood gas analyses because of an overemphasis on quantitative measurements, rather than on a thorough assessment of the patient's disease. A complete clinical evaluation of the patient, not isolated quantitative measurements, must be our primary concern. Numerical values of blood gases have by themselves little absolute merit and must always be interpreted in relation to the clinical history and status of the patient.