摘要目的 观察前臂平衡压(Parm)是否有助于预测容量负荷试验对ICU少尿患者增加尿量的效果.方法 前瞻性观察研究.选血流动力学稳定[平均动脉压(MAP)＞65 mmHg(1 mmHg=0.133kPa),心率＜120次/min,动脉血乳酸＜2 mmol/L]且连续3h尿量＜0.5 ml· kg-1·h-1的少尿患者,以30 min输注乳酸林格液500 ml进行容量负荷试验,记录容量负荷试验前后MAP、心率、动脉血乳酸、中心静脉压(CVP)、30s和60s Parm.容量负荷试验后1h较试验前1h的尿量增加量大于0.5 ml· kg-1·h-1定义为肾脏反应阳性,尿量增加量≤0.5 ml·kg-1·h-1定义为肾脏反应阴性.结果 共纳入30例少尿患者,男性17例,女性13例,年龄(54.2±16.3)岁.容量负荷试验后,患者心率下降[(84±13)次/min比(80±10)次/min,P＜0.01],CVP上升[(7.0±2.4)mmHg比(8.8±2.6)mmHg,P＜0.01],30s Parm[(33.4±5.3) mmHg比(35.4±5.8) mmHg,P＜0.01]和60s Parm[(26.9±4.5) mmHg比(28.7±5.0)mmHg,P＜0.01]增高,1h尿量增加[(18.5±8.8)ml/h比(64.1±38.3)ml/h,P＜0.01],而MAP和乳酸无明显改变(P＞0.05).肾脏反应阳性者18例,肾脏反应阴性者12例.肾脏反应阳性者容量负荷试验前MAP[(78.1±10.7)mmHg比(91.2±11.7) mmHg,P＜0.01]、30s Parm[(30.4±3.8) mmHg比(38.0±3.7) mmHg,P＜0.01]和60s Parm[(24.3±2.5)mmHg比(30.8±4.0)mmHg,P＜0.01]均低于肾脏反应阴性者;而心率、CVP、乳酸、年龄、体重两者间差异无统计学意义(P＞0.05).容量负荷试验后,肾脏反应阳性者MAP、30s和60s Parm仍低于肾脏反应阴性者(P＜0.05);而心率、CVP、乳酸两者间差异无统计学意义(P＞0.05).相关性分析显示,容量负荷试验前30s Parm、60s Parm、MAP与容量负荷试验后1h尿量呈负相关(r=-0.75,P＜0.01;r=-0.69,P＜0.01;r=-0.46,P＜0.05),而心率、CVP与容量负荷试验后1h尿量不相关(P＞0.05).接受者操作特征曲线显示,30s Parm具有最大曲线下面积为0.94(95％CI0.84～1.05,P＜0.01),以35.5 mmHg为截止值,敏感度为94.4％,特异度为91.7％,阳性似然比为11.37.结论 对血流动力学稳定的少尿重症患者,若Parm低于正常参考值,扩容补液使尿量增加的可能性大.Parm可用于预测容量负荷试验对增加尿量的效果.

abstractsObjective To evaluate whether arm equilibrium pressure (Parm) is helpful to predict the effect of fluid load in improving oliguria in intensive care unit(ICU) patients.Methods Hemodynamically stable patients [mean artery pressure (MAP)＞65 mmHg (1 mmHg=0.133 kPa),heart rate (HR)＜120 beats/min,lactic acid＜2 mmol/L] with urine output (UO)＜0.5 ml· kg-1· h-1 for 3 consecutive hours were enrolled.The fluid loading was performed by infusion of ringer's lactate 500 ml within 30 minute after baseline hemodynamic data were recorded.The positive renal response was defined as UO increased more than 0.5 ml· kg-1 · h-1 1 hour after fluid challenge,otherwise was negative.Results A total of 30 oliguric ICU patients were enrolled including 17 males and 13 females with median age (54.2±16.3) years.After fluid load,patients' HR decreased[(84± 13)beat/min vs.(80± 10) beat/min,P＜0.01],central venous pressure (CVP) increased[(7.0±2.4)mmHg vs.(8.8±2.6) mmHg,P＜0.01],30s Parm [(33.4±5.3) mmHg vs.(35.4±5.8) mmHg,P＜0.01] and 60s Parm [(26.9±4.5) mmHg vs.(28.7±5.0) mmHg,P＜0.01] increased,and UO [(18.5±8.8)ml/h vs.(64.1±38.3)ml/h,P＜0.01] increased significantly,while MAP and lactic acid did not change (P＞0.05).There were eighteen renal responders and 12 patients did not response.In responding group,MAP[(78.1 ±10.7) mmHg vs.(91.2±11.7) mmHg,P＜0.01],30s Parm[(30.4±3.8) mmHg vs.(38.0±3.7) mmHg,P＜0.01]and 60s Parm [(24.3±2.5) mmHg vs.(30.8±4.0) mmHg,P＜0.01] before fluid load were lower than those in negative group.HR,CVP,lactic acid,age and body weight were comparable between two groups (P＞0.05).After volume loading,MAP,30s and 60s Parrn in positive group were still lower than those in negative group (P＜0.05),while HR,CVP and lactic acid were similar (P＞0.05).Correlation analysis showed that baseline 30s Parm (r=-0.75,P＜0.01),60s Parm (r=-0.69,P＜0.01),and MAP (r=-0.46,P＜0.05) were negatively correlated with 1 h UO after fluid load,but HR and CVP were not (P＞0.05).The receiver operating curve (ROC) showed that 30s Parm had the largest area under curve (AUC) of 0.94 (95％ CI 0.84-1.05,P＜0.01),which 35.5 mmHg was the best threshold with sensitivity 94.4％ and specificity 91.7％(likelihood ratio 11.37).Conclusion In hemodynamically stable oliguric ICU patients,if Parm is lower than normal reference value,volume expansion is more likely to increase UO.Thus Parm can be used to predict the effect of fluid loadon UO.