Diagnosis of Acid-base Imbalance by Stewart's Physicochemical Approach and Mortality Prediction in Severe Burn Patients with Inhalation Injury / 대한구급학회지

ABSTRACT

BACKGROUND: Acid-base derangement are commonly encountered in critically ill patients. This study is to investigate underlying mechanisms of acid-base imbalance and also to examine whether they can predict mortality in burn patients. METHODS: We retrospectively reviewed 73 severely burned patients who had admitted to burn intensive care unit, from January to July in 2004. All the patients had inhalation injury, identified by bronchoscopic examination. We analyzed the type and nature of the acid-base imbalances from arterial blood gas analysis, electrolytes and other biological tests between survivors and non-survivors for 30 days after admission. RESULTS: Acidosis was the most common disorder during the early and late hospital periods. Large fractions of those showed decreased strong ion difference (SID), increased anion gap corrected by albumin (AGc) and [Cl-]corrected. Mixed disorder and alkalosis emerged after the 7(th) hospital day. As time went by, albumin, PaO2/FiO2 ratio, pH and SID were more decreased in non-survivors (n=28) than in survivors (n=45) while [Cl-] corrected, alveolar-arterial oxygen tension gradients, peripheral WBC counts and CRP were more increased in non-survivors than in survivors. In the area under the receiver operating characteristic curves for mortality prediction, APACHE II score and % of total body surface area (%TBSA) burn were high 0.866 (95% CI; 0.785~0.946) for APACHE II score, 0.817 (95% CI; 0.717~0.918) for %TBSA burn. CONCLUSIONS: In burned patients with inhalation injury, various types of acid-base imbalances and electrolytes abnormalities emerged after resuscitation and so, more careful attentions pursued for correcting underlying acid-base derangement.