ABSTRACT
Objective 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.
ABSTRACT
Objective To observe the changes of arm equilibrium pressure (Parm) in different occlusion time,the reference range of Parm in hemodynamic stable patients,and to explore the relationship between Parm and systemic hemodynamic parameters.Methods Mechanically ventilated postoperative abdominal surgery patients who admitted to ICU with stable hemodynamic status were enrolled.After hemodynamic data were recorded,arm stop-flow maneuvers were performed to measure Parm.At 10,20,30,40,50,60 seconds after occlusion,arterial pressure were measured twice within 5 minutes and recorded as the average value.Results Thirty patients were included.The Parm decreased gradually with the prolongation of the occlusion time.The value was not stable within 60 s,but the reducing extent was not obvious after 40s.The 95％ reference range of Parm 30 S was 23-44 mmHg(1 mmHg =0.133 kPa) and Parm 60 S was 19--35 mmHg.Parm at 30 s and 60 s were positively correlated with systolic arterial pressure,diastolic arterial pressure,mean arterial pressure,central venous pressure (all P ＜ 0.001),but not heart rate and pulse pressure.Linear regression analysis showed that Parm at 10 s,20 s,30 s only had linear correlation with diastolic arterial pressure (10 s,β =0.504,P =0.001;20 s,β =0.297,P =0.005;30 s,β =0.231,P =0.015),and Parm at 40 s,50 s,60 s were linear correlation with diastolic arterial pressure (40 s,β =0.220,P =0.004;50 s,β =0.210,P =0.004;60 s,β =0.213,P =0.004) and central venous pressure (40 s,β =0.516,P =0.018;50 s,β =0.513,P =0.01;60 s,β =0.472,P =0.023).Conclusion In mechanically ventilated postoperative abdominal surgery patients with stable hemodynamic status,Parm decreases when occlusion time is prolonged,which is not stable within 60 s occlusion.Arterial blood pressure and central venous pressure are positively correlated with Parm.