血浆渗透压冰点下降法与不同公式法之间比对

Comparison plasma osmolality between freezing point depression method and different calculation formulas

目的探讨16个常见血浆渗透压计算公式,评估血浆渗透压的公式计算值与冰点下降法测量值最为符合的计算公式;利用所收集数据模拟出一个与患者的血浆渗透压较为相符的公式。方法利用冰点下降法测量血浆渗透压,同时使用Vitros 5.1干化学分析仪检测血浆钠(Na)、钾(K)、氯(Cl)、葡萄糖(Glu)、尿素(Urea)浓度。运用16个计算公式计算出对应的血浆渗透压,运用Passing-Bablok回归来判断拟合优度,并与实测值进行配对t检验。采用多元线性回归及配对t检验的方法,拟合一个与测量值最符合的计算公式。结果血浆渗透压的公式计算值与测量值最为符合的是公式1.86(CNa+CK)+CGlu+CUrea+10;利用多元线性回归得出的回归公式为1.86CNa+2.75CK+1.16CGlu+0.92CUrea+5.77。结论初步认为可以使用1.86CNa+2.75CK+1.16CGlu+0.92CUrea+5.77作为血浆渗透压的计算公式。

ObjectiveSixteen common blood osmotic pressure calculation formulas were investigated to evaluate the calculation formula of the plasma osmotic pressure formula and the freezing point depression method.The collected data were used to simulate a formula that was consistent with the patient′s plasma osmotic pressure.MethodsThe osmotic pressure of plasma was measured by the freezing point descent method.Plasma sodium(Na),potassium(K),chloride(Cl),glucose(Glu),and urea(Urea)concentrations were measured by using a Vitros 5.1 dry chemistry analyzer.Sixteen formulas were used to calculate the corresponding plasma osmotic pressure.The Passing-Bablok regression was used to determine the goodness of fit and paired t test was performed with the measured values.A multiple linear regression and paired t test method was used to fit a formula that most closely matched the measured values.ResultsThe formula of plasma osmotic pressure and the measured value was the most consistent with the formula 1.86(C Na+C K)+C Glu+C Urea+10;the regression formula using multiple linear regression was 1.86 C Na+2.75 C K+1.16 C Glu+0.92 C Urea+5.77.ConclusionIt is tentatively concluded that the formula 1.86 C Na+2.75 C K+1.16 C Glu+0.92 C Urea+5.77 can be used as the formula for calculating plasma osmolality.