Metabolic acidosis and strong ion gap in critically ill patients with acute kidney injury.

Cai-Mei Zheng,Wen-Ya Ma,Chia-Chao Wu,Wen-Chih Liu,Jing-Quan Zheng,Kuo-Chin Hung,Chien-Lin Lu,Min-Tser Liao,Kuo-Cheng Lu

doi:10.1155/2014/819528

Abstract

Purpose. To determine the influence of physicochemical parameters on survival in metabolic acidosis (MA) and acute kidney injury (AKI) patients. Materials and Methods. Seventy-eight MA patients were collected and assigned to AKI or non-AKI group. We analyzed the physiochemical parameters on survival at 24 h, 72 h, 1 week, 1 month, and 3 months after AKI. Results. Mortality rate was higher in the AKI group. AKI group had higher anion gap (AG), strong ion gap (SIG), and apparent strong ion difference (SIDa) values than non-AKI group. SIG value was higher in the AKI survivors than nonsurvivors and this value was correlated serum creatinine, phosphate, albumin, and chloride levels. SIG and serum albumin are negatively correlated with Acute Physiology and Chronic Health Evaluation IV scores. AG was associated with mortality at 1 and 3 months post-AKI, whereas SIG value was associated with mortality at 24 h, 72 h, 1 week, 1 month, and 3 months post-AKI. Conclusions. Whether high or low SIG values correlate with mortality in MA patients with AKI depends on its correlation with serum creatinine, chloride, albumin, and phosphate (P) levels. AG predicts short-term mortality and SIG value predicts both short- and long-term mortality among MA patients with AKI.

Highlights

Metabolic acidosis is an acid-base disorder of the blood and is an especially challenging condition among patients in intensive care units (ICUs)
We evaluated the prognosis of ICU patients with metabolic acidosis based on their Simplified Acute Physiology Score (SAPS-II) and their results on the Acute Physiology and Chronic Health Evaluation(APACHE-) II and IV, and we examined the influence of the apparent strong ion difference (SIDa), strong ion gap (SIG), AG, and corrected anion gap (CAG) on mortality at 24 h, 72 h, one week, one month, and 3 months post-acute kidney injury (AKI)
We evaluated the effects of the laboratory parameters on survival in patients with metabolic acidosis who developed AKI (Table 2)

Summary

Introduction

Metabolic acidosis is an acid-base disorder of the blood and is an especially challenging condition among patients in intensive care units (ICUs). The SID is the difference between the levels of fully dissociated anions and cations in the serum, and the total weak acid concentration is primarily determined by albumin and phosphate, which influence blood pH and the concentration of bicarbonate. The analysis of these serum parameters allows the identification of acid-base disorders in complex clinical situations which might otherwise confound their identification based on AG and bicarbonate level alone and provides insight regarding the underlying pathology [7]

Methods

Results

Discussion

Conclusion