A study to determine quantitative predictors for development of third space fluid accumulation in adult patients with dengue

Abstract

INTRODUCTION: Prediction of severe illness remains the most important measure in preventing mortality associated with dengue. Increased vascular permeability leading to reduced intravascular volume is the hallmark of dengue shock syndrome. Third space fluid accumulation (TSFA) reflects severe vascular permeability and therefore, it is important to quantitatively identify parameters which predict the occurrence of TSFA in dengue. METHODS:102 patients with confirmed dengue were prospectively followed up for clinical, haematological, biochemical parameters and for evidence of TSFA by serial utrasonography. These parameters were tested against development of TSFA using Receiver Operating Characteristic [ROC] curves to identify quantitative predictors of development of TSFA. RESULTS: 102 patients (52 males) with mean age 28.3 years (SD 11.8), TSFA was detected in 34/95 [36%) after admission; 21/95 developed ascites at mean 5.7 days of illness (SD 1.3) and 33/95 had pleural effusion at 5.4 days (SD 1.5). Onset of TSFA could be identified using percentage rises of highest PCV (p= 0.002) where 6.5% rise of PCV predicted TSFA(sensitivity 61%, specificity 62%)], highest Hb (p=0.017) where rise of 6.1% in Hb predicted TSFA (sensitivity 55%, specificity 64%), lowest recorded platelet count (p<0.000) where platelet count of 48500/mm3 or less predicted TSFA (sensitivity of 83%, specificity 51) post-admission fluid input-output balance per day (p 0.002) where positive balance more than 777cc/day predicted TSFA (sensitivity 65%, specificity 64%). CONCLUSIONS: Rise of PCV and Hb, platelet count, WBC count and daily fluid balance appear to be useful quantitative predictors of TSFA in dengue.