动脉血气分析结果可靠的血样放置时限

The Period of Blood Samples Deposed to Get Reliable Arterial Blood Gas Analysis Results

目的确定动脉血样采集后得到准确可靠血气分析检测结果的标本放置时限。方法选择择期行口腔颌面外科手术患者40例。全麻诱导后气管插管，进行机械通气后30min，采集桡动脉血液，进行血气分析，红细胞压积、血红蛋白、血糖、乳酸、电解质测定。检测时点分别为采血后即刻（TO）、采血后15min（T1）、采血后30min（T2）、采血后45min（T3）、采血后60min（T4）、采血后90min（T5）、采血后120min（T6）、采血后180min（T7）和采血后240rain（T8）。结果从T4开始pH和Pa02比T0明显降低，PaC02明显增高，P〈0．05。HC03-、TC02和BE在T7和T8时刻显著降低。Sa02在各时点无明显变化。从T4开始红细胞压积、血红蛋白和乳酸比TO明显增高，P〈0．05。从T4开始血糖比TO明显降低，P〈0．05。Na＋浓度略降低，K＋浓度略增高，但均无统计学意义，P〉0．05。Ca2＋浓度在各时点无明显差异。结论动脉血采集常温放置45min后血气分析结果仍然准确可靠，具有临床指导意义。

Objective To investigate the period that arterial blood samples can be deposed in order to get reliable arterial blood gas analysis results.Methods Forty patients undergoing selective oral and maxillofacial surgeries were enrolled in the study.The patients were mechanically ventilated after trachea intubation.Radial artery samples were conlleeted 30 minutes after ventilation for arterial blood gas analysis and to test hematocrit,hemoglobin,glucose,lactic acid and plasma electrolytes at immediately after drawing blood（T0）, 15min later（T1）,30min later（T2）,45min later（T3）,60min later（T4）,90min later（TS）,120min later（T6）,180min later（T7） and 240min later（T8）.Results pH and PaO2 decreased after T4 compared with those at T0,and PaCO2 increased significantly after T4,P 〈 0.05.HCO3-,TCO2 and BE decreased at T7 and TS.SaO2 showed no different changes.Hematocrit,hemoglobin and lactic acid increased after T4,P 〈 0.05.Glucose declined obviously after T4.The concentrations of plasma electrolytes had no statistical changes all the time.Conclusion The results of arterial blood gas analysis are reliable until arterial blood samples deposed for 45 minutes.