电解质和酸碱平衡紊乱的生物化学检验(酸碱)分析报告.ppt

Case study No. 10 76 yo ? with documented chronic hypercapnia secondary to severe COPD has been in ICU for 3 days while being tx for pneumonia. She had been stable for past 24 hours and was transferred to general floor. Pt was on 2L oxygen ABG VS: pH 7.44 BP 135/95 mmHg PCO2 63 mmHg Pulse 110/min PO2 52 mmHg RR 22/min HCO3 42 mmol/L BE +16 mmol/L MV 10L SaO2 86% . Interpretation: Chronic ventilatory failure (resp. acidosis) with uncorrected hypoxemia Case No. 10 cont’d She was placed on 3L and monitored for next hour. She remained alert, oriented and comfortable. ABG was repeated: pH 7.36 BP 140/100 mmHg PCO2 75 mmHg Pulse 105/min PO2 65 mmHg RR 24/min HCO3 42 mmol/L BE +16 mmol/L MV 4.8L SaO2 92% . Pt’s ventilatory pattern has changed to more rapid and shallow breathing. Although still acceptable the pH and CO2 are trending in the wrong direction. High-flow oxygen may be better for this pt to prevent intubation Take Home Message: Valuable information can be gained from an ABG as to the patients physiologic condition Remember that ABG analysis if only part of the patient assessment. Be systematic with your analysis, start with ABC’s as always and look for hypoxia (which you can usually treat quickly),  then follow the four steps. A quick assessment of patient oxygenation can be achieved  with a pulse oximeter which measures SaO2. It’s not magic understanding ABG’s, it just takes a little practice! Any Questions? Practice ABG’s PaO2 90 SaO2 95 pH 7.48 PaCO2 32 HCO3 24 PaO2 60 SaO2 90 pH 7.32 PaCO2 48 HCO3 25 PaO2 95 SaO2 100 pH 7.30 PaCO2 40 HCO3 18 PaO2 87 SaO2 94 pH 7.38 PaCO2 48 HCO3 28 PaO2 94 SaO2 99 pH 7.49 PaCO2 40 HCO3 30 6. PaO2 62 SaO2 91 pH 7.35 PaCO2 48 HCO3 27 PaO2 93 SaO2 97 pH 7.45 PaCO2 47 HCO3 29 PaO2 95 SaO2 99 pH 7.31 PaCO2 38