Bioelectrical impedance analysis values as markers to predict severity in critically ill patients

Abstract

BACKGROUND: We investigated bioelectrical impedance analysis (BIA)-derived parameters in critically ill patients to evaluate any differences between survivors and non-survivors. METHODS: We calculated severity scores for 241 critically ill surgical patients (161 male and 80 female; mean age, 62.9 years) using three severity scoring systems (Acute Physiology and Chronic Health Evaluation II, Sequential Organ Failure Assessment, and Simplified Acute Physiology Score III). Body composition was measured using a portable BIA device for segmental BIA. RESULTS: Among the BIA values, impedance (odds ratio [OR], 0.99; P<0.001), reactance (OR 0.90; P<0.001), and phase angle (PhA) (OR, 0.53; P<0.001) were highly statistically significant for predicting mortality in univariate and multivariate logistic regression analysis. Comparison of area under the curve (AUC) between severity scoring systems and BIA values showed statistically significant differences between reactance and PhA with all three severity scoring systems. Covariate-adjusted receiver operating characteristic curve analysis showed that compared with severity scoring, all three BIA values (impedance, reactance, and PhA) had higher AUC values. CONCLUSION: PhA, impedance, and reactance determined by BIA in critically ill patients were associated with mortality outcomes and revealed stronger predictive power for mortality than severity scoring systems commonly used in an intensive care unit.

목적: 중환자에게 생체전기임피던스분석법을 적용하여 얻어진 결과값들이 사망예측력을 갖는지 알아보고자 하였다. 방법: 아주대병원 외과계 중환자실에 입실한 241명의 환자(남 161명, 여 80명,평균연령 62.9세)를 대상으로 이동식 생체전기임피던스기계를 이용하여 검사를 진행하였다.사망군과 생존군 간에 3개의 중증도 지표(Acute Physiology and Chronic Health Evaluation II, Sequential Organ Failure Assessment, and Simplified Acute Physiology Score III )와 생체전기임피던스분석으로 얻어진 결과값들을 비교 분석하였다. 결과: 생체전기임피던스분석법 결과값 중, impedance (odds ratio [OR], 0.99; P<0.001), reactance (OR 0.90; P<0.001)와 phase angle (PhA) (OR, 0.53; P<0.001) 모두 단변량 및 다변량 분석상에서 유의한 사망예측률을 보였다.다중요인보정 receiver operating characteristic curve 분석에서도 생체전기분석법에서 얻어진 impedance, reactance, phase angle 값 모두 세 중증도 지표값보다 통계적으로 높은 area under the curve 값들을 보였다. 결론: 생체전기임피던스분석법에서 얻어진 impedance, reactance, phase angle 값들은 환자의 사망률과 강한 연관성이 있었으며,기존에 중환자실에서 사용하고 있는 중증도 지표들보다 더 강한 사망예측력을 갖고 있었다.