NURS 3664 Lecture Notes - Lecture 10: Pulse Oximetry, Peripheral Artery Disease, Nail Polish
Document Summary
Abgs are measured to determine oxygenation status and acid base balance. Get a good picture of respiratory status. An abg is a blood test that measures the acidity, or ph, and the levels of oxygen (o2) and carbon dioxide (co2) from an artery. The test is used to check the function of the patient"s lungs and how well they are able to move oxygen and remove carbon dioxide. Arterial oxygen saturation can be monitored by pulse oximetry. Peripheral capillary oxygen saturation (spo2) is estimated percentage of oxygenated hemoglobin compared to the amount of hemoglobin in the blood (96-99%) Pulse oximetry uses light absorption at two wavelengths to determine hemoglobin saturation. Pulse oximetry is non-invasive and provides immediate and continuous data. Pulse oximetry does not assess ventilation (pco2) or acid base status. Pulse oximetry becomes unreliable when saturations fall below 70-80%. Technical sources of error (ambient or fluorescent light, hypoperfusion, nail polish, skin pigmentation)
