Pathophysiology of Acid Base Balance

Intensive and Critical Care Nursing (2008) 24, 28—40

ORIGINAL ARTICLE

Pathophysiology of acid base balance: The theory practice relationship
Sharon L. Edwards ∗
Buckinghamshire Chilterns University College, Chalfont Campus, Newland Park, Gorelands Lane, Chalfont St. Giles, Buckinghamshire HP8 4AD, United Kingdom
Accepted 13 May 2007

KEYWORDS
Acid base balance; Arterial blood gases; Acidosis; Alkalosis

Summary There are many disorders/diseases that lead to changes in acid base balance. These conditions are not rare or uncommon in clinical practice, but everyday occurrences on the ward or in critical care. Conditions such as asthma, chronic obstructive pulmonary disease (bronchitis or emphasaemia), diabetic ketoacidosis, renal disease or failure, any type of shock (sepsis, anaphylaxsis, neurogenic, cardiogenic, hypovolaemia), stress or anxiety which can lead to hyperventilation, and some drugs (sedatives, opoids) leading to reduced ventilation. In addition, some symptoms of disease can cause vomiting and diarrhoea, which effects acid base balance. It is imperative that critical care nurses are aware of changes that occur in relation to altered physiology, leading to an understanding of the changes in patients’ condition that are observed, and why the administration of some immediate therapies such as oxygen is imperative. © 2007 Elsevier Ltd. All rights reserved.

Introduction
The implications for practice with regards to acid base physiology are separated into respiratory acidosis and alkalosis, metabolic acidosis and alkalosis, observed in patients with differing aetiologies. By understanding normal physiological principles and how they relate to clinical situations can enhance patient care. A good understanding of
Present address: Department of Pre-registration Nursing, Faculty of Health Studies, Buckinghamshire Chilterns University College, United Kingdom. Tel.: [phone]x2123 (Off.)/1442 876772 (Res.); fax: [phone]. E-mail

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