危重患者胸腔积液超声测量新方法的建立与应用

目的 探索危重患者胸腔积液超声精确测量的新方法 .方法 选择收住急诊ICU的危重患者46例,应用超声在平卧位、呼气末测定胸腔积液的高度(H)、中间层积液的面积(S)和在后背正中线、腋后线处的厚度(T1、T2),以H×S估算胸腔积液量(Vc),胸腔置管充分引流获取实际积液量.分析胸腔积液实际量与积液高度、厚度、面积及估算量的相关性,比较不同指标和方法 估算积液量的准确性.结果 在总组和各亚组中,胸腔积液实际量与S、(H和S)、Vc的相关性明显好于T1、T2和H.超声测量新方法 获取的估算量与实际积液量有较好的相关性(r=0.778,P＜0.001),而且非常接近实际积液量(平均相差56 ml),尤其在积液量＜500 ml时两者的差别无统计学意义[(417±94)ml对(402±95)ml,t=1.095,P=0.285].Logistic逐步回归分析和受试者工作特征曲线(ROC)分析均表明,以H、S、T1、T2预测实际积液量＞500 ml、400 ml和300 ml,其中以S最为可靠,其阈值分别为30.3 cm2、28.3 cm2和23.1cm2,相应的敏感性和特异性分别为0.77和0.88,0.72和1.0,0.95和1.0.结论 基于积液面积测定基础上建立的胸腔积液超声新测量方法 较传统方法 更可靠和精确,具有重要的临床价值,且测定技术简单,值得推广应用.

Abstract：

Objective To develop a new method to measure pleural effusion volume by ultrasound in critically ill patients. Methods Forty-six critically ill patients admitted to emergency ICU were involved.The height of effusion (H),area of effusion at the middle section (S), thickness of effusion at middle-back line (T1) and posterior axillary line (T2) were measured by ultrasound in supine position at the end of expiration. The measured volume of pleural effusion (Vc) was calculated by H×S,and the actual volume of drainage (V) within 2 hours was also recorded. The correlation of actual volume of pleural effusion (V)with effusion height (H) ,thickness (T1, T2), area (S) and the calculated volume (Vc) were analyzed to decide the most accurate index and method. Results There was much better correlation between actual volume of effusion and S, (H & S), Vc, than these between V and T1 ,T2, H in all patients and subgroup, Vc had good correlation with V and very close to V(the average difference was 56 ml) when the actual volume was less than 500 ml,there was no difference[(417 ± 94)ml vs (402±95)ml, t = 1.095, P = 0. 285]. Both Logistic regression analysis and receiver operating characteristic (ROC) curve showed S was the most reliable index to predict the actual volume to exceed 500 ml,400 ml,and 300 ml when compared with H,S,T1 and T2. The corresponding threshold was 30.3 cm2 , 28.3 cm2 and 23. 1 cm2 , with the sensitivity and specificity of 0. 77 and 0. 88,0.72 and 1.0,0.95 and 1.0, respectively. Conclusions This new method based on measuring the area of effusion by ultrasound is more efficient and reliable than those traditional ones to measure the volume of pleural effusion. It's clinically valuable and easy to perform, and deserves broad application.

Development of a new method to measure pleural effusion volume by ultrasound in critically ill patients

Objective To develop a new method to measure pleural effusion volume by ultrasound in critically ill patients. Methods Forty-six critically ill patients admitted to emergency ICU were involved.The height of effusion (H),area of effusion at the middle section (S), thickness of effusion at middle-back line (T1) and posterior axillary line (T2) were measured by ultrasound in supine position at the end of expiration. The measured volume of pleural effusion (Vc) was calculated by H×S,and the actual volume of drainage (V) within 2 hours was also recorded. The correlation of actual volume of pleural effusion (V)with effusion height (H) ,thickness (T1, T2), area (S) and the calculated volume (Vc) were analyzed to decide the most accurate index and method. Results There was much better correlation between actual volume of effusion and S, (H & S), Vc, than these between V and T1 ,T2, H in all patients and subgroup, Vc had good correlation with V and very close to V(the average difference was 56 ml) when the actual volume was less than 500 ml,there was no difference[(417 ± 94)ml vs (402±95)ml, t = 1.095, P = 0. 285]. Both Logistic regression analysis and receiver operating characteristic (ROC) curve showed S was the most reliable index to predict the actual volume to exceed 500 ml,400 ml,and 300 ml when compared with H,S,T1 and T2. The corresponding threshold was 30.3 cm2 , 28.3 cm2 and 23. 1 cm2 , with the sensitivity and specificity of 0. 77 and 0. 88,0.72 and 1.0,0.95 and 1.0, respectively. Conclusions This new method based on measuring the area of effusion by ultrasound is more efficient and reliable than those traditional ones to measure the volume of pleural effusion. It's clinically valuable and easy to perform, and deserves broad application.