Prognostic value of decreased vasopressin modulation in the late-phase of septic shock patients / 中华危重病急救医学

ABSTRACT

Objective To investigate the prognostic value of decreased vasopressin (VP)modulation in the late-phase of septic shock. Methods A prospective study was conducted. Fifty-five septic shock patients hospitalized in intensive care unit (ICU)of the First Hospital of Hebei Medical University from January 2012 to February 2014 were enrolled. All patients received 3% hypertonic saline solution infusion. Serum concentrations of sodium and VP were measured before and after hypertonic saline solution infusion. Patients with ratio of difference in sodium and VP before and after infusion of 3%hypertonic saline (△VP/△Na)≤0.5 pg/mmol were defined as non-responders,and who>0.5 pg/mmol were defined as responders. The levels of lactic acid,C-reactive protein (CRP),and vasoactive drug〔dopamine(DA)and norepinephrine(NE)〕usage between the two groups were compared. The 28-day mortality,live time in the dead,and ICU day in survivors were analyzed between the two groups. The receiver operating characteristic curve (ROC curve)was drawn to assess prognostic value of VP. Results There were 30 cases (54.5%) in non-responsive group,and 25 (45.5%)in responsive group. There were no significant differences in the age,acute physiology and chronic health evaluationⅡ (APACHEⅡ)score,central venous pressure (CVP),blood pressure, plasma albumin level,sodium level before and after hypertonic saline solution infusion between the two groups. The baseline level of VP in the non-responsive group was markedly lower than that of the responsive group (ng/L10.66± 1.57 vs. 17.13 ±5.12,t=6.091,P<0.001). After hypertonic saline solution infusion,the VP level was also significantly decreased compared with that in the responsive group(ng/L11.65±1.74 vs. 22.50±5.31,t=9.758,P<0.001). The non-responders showed higher lactic acid (mmol/L3.04±0.55 vs. 2.28±0.38,t=-5.881,P<0.001) and CRP (mg/L117.9±23.0 vs. 94.9±17.0,t=-4.143,P<0.001),and received larger dosage of vasoactive drugs〔DA(μg·kg-1·min-1)14.8±3.9 vs. 8.9±1.6,t=-5.725,P<0.001;NE(μg·kg-1·min-1)0.96±0.42 vs. 0.40± 0.09,t=-5.625,P<0.001〕for maintaining blood pressure compared with those in responders. The non-responsive group showed higher 28-day mortality(66.7%vs. 40.0%,χ2=3.911,P=0.048)and longer ICU day(days9.9±2.3 vs. 6.7±1.7,t=-4.044,P<0.001),but the live time in the dead showed no difference between non-responsive group and responsive group(days5.8±1.9 vs. 6.1±2.3,t=0.384,P=0.704). ROC curve showed that the area under ROC curve(AUC)forΔVP/ΔNa predicting the outcome was 0.828,and theΔVP/ΔNa threshold value of 0.5 pg/mmol had the sensitivity of 66.7%and specificity of 64.0%for prediction of the outcome(95%confidence interval0.722-0.934). Conclusion Osmotic pressure-regulated VP secretion was impaired and decreased in the late-phase of septic shock, and made the sense in prognosis.