title: Interpretation of arterial blood gases: a clinical guide for nurses.
abstract: Arterial blood gas analysis has become an essential skill for all healthcare practitioners. It provides important information with regard to adequacy of ventilation, oxygen delivery to the tissues and acid-base balance. Although each patient's clinical presentation will be judged individually, situations that warrant analysis of a blood gas sample include respiratory compromise, post-cardiorespiratory arrest, evaluation of interventions such as oxygen therapy, respiratory support and as a baseline before surgery. This article reviews the different parameters that are measured by various machines, with a focus on basic measurement of arterial blood gases. These include partial pressure of carbon dioxide in arterial blood (PaCO(2)), partial pressure of oxygen in arterial blood (PaO(2)), bicarbonate levels (HC0(3)(-)) in arterial blood and base excess/deficit. The physiology of acid-base balance is reviewed and the causes and presentation of the four acid-base disturbances is described. A systematic method to aid arterial blood interpretation is identified, together with discussion regarding the importance of interpreting PaO(2) readings in relation to the amount of inspired oxygen a patient is receiving (FiO(2)), the practice of temperate correction and the relationship between standardized and actual bicarbonate readings.
authors.affiliation: Kingston University and St George's Hospital Medical School, London, UK.
authors.forename: Heidi
authors.initials: H
authors.lastname: Simpson
mesh_terms: D000137:Acid-Base Imbalance / Q000097:blood / Q000145:classification / Q000175:diagnosis; D015982:Bias; D001784:Blood Gas Analysis / Q000295:instrumentation / Q000379:methods / Q000451:nursing; D003627:Data Interpretation, Statistical; D006706:Homeostasis; D006801:Humans; D008487:Medical History Taking; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods / Q000451:nursing; D009730:Nursing Assessment / Q000379:methods*; D010101:Oxygen Consumption; D010808:Physical Examination; D012016:Reference Values; D013696:Temperature