Agreement of simplified Fencl-Stewart with Figge-Stewart method in diagnosing metabolic acidosis in critically ill children

Abstract

Background The traditional Henderson-Hasselbalch approach hasproven to be imprecise in critically ill patients. Stewart’s approachcan detect metabolic acidosis missed by traditional approach,including acidosis caused by increased unmeasured agreement(UA). The complexity of Stewart’s method leads to developmentof simpler modifications, simplified Fencl-Stewart and Figge-Stewart method. Agreement between both modifications isunknown.Objective This study aimed to measure the agreement of simplifiedFencl-Stewart with Figge-Stewart method in diagnosing metabolicacidosis in critically ill children.Methods The was performed in Hasan Sadikin General Hospital,Bandung from July to August 2006, involving <14 year-old criticallyill children. Blood samples for gas analysis, sodium, potassium,chloride and albumin measurement were taken simultaneously. Testresult was analyzed with simplified Fencl-Stewart and Figge-Stewartmethod and recorded with Excell spreadsheet. PASS was used forinterim analysis and DAG_Stat for raw agreement indices andKappa calculations.Results Forty-five (31 males, 14 females) children were enrolled.Acid base disturbances based on Stewart’s method were identifiedin 10 subjects with normal base excess and nine with normalbicarbonate. Significant increase of UA was detected in 11 of 45subjects with simplified Fencl-Stewart method, compared to thatof 12 subjects with Figge-Stewart method. Raw agreement indicesshowed 95.65% and 98.51% agreement for positive and negativeresult, Kappa was 0.94 (P=0.0000).Conclusions Excellent agreement is shown between simplifiedFencl-Stewart and Figge-Stewart method in diagnosing metabolicacidosis in critically ill children. Increased UA can be assessedwith both methods.

Agreement of Simplified Fencl-Stewart With Figgestewart Method in Diagnosing Metabolic Acidosis in Critically Ill Patients

“…The results of this research indicated a good suitability betweeen the simplified Fencl-Stewart method to Figge-Stewart method with a sensitivity of 80% and a specificity of 80%. In contrary, a research performed by Sinaga et al 24 showed an excellent suitability between the simplified Fencl-Stewart method and the Figge-Stewart method in diagnosing critical metabolic acidosis with a positive result agreement of 95.65% and a negative result agreement of 98.51%. 24 Meanwhile, a research conducted by Kurnia et al 25 comparing traditional method with the simplified Fencl-Stewart method in assessing the unmeasured anion as a cause of metabolic acidosis found a sensitivity of 94.3% and a specificity of 84%.…”

“…In contrary, a research performed by Sinaga et al 24 showed an excellent suitability between the simplified Fencl-Stewart method and the Figge-Stewart method in diagnosing critical metabolic acidosis with a positive result agreement of 95.65% and a negative result agreement of 98.51%. 24 Meanwhile, a research conducted by Kurnia et al 25 comparing traditional method with the simplified Fencl-Stewart method in assessing the unmeasured anion as a cause of metabolic acidosis found a sensitivity of 94.3% and a specificity of 84%. On the other hand, in comparing traditional method with the Figge-Stewart method in assessing the unmeasured anion, the reserach showed a sensitivity of 100% and a specificity of 76%.…”

Association of Acid-Base Parameters With Lactate Level in Critically Ill Patients With Metabolic Acidosis

“…5 The lack of this method is the dependence of HCO 3 -serum level toward PaCO 2 and it is difficult to detect acid-base imbalance in complex metabolic situations especially for critically ill patients. 4,6 Siggaard-Anderson completed Henderson-Hasselbalch equation with BE calculation. Base excess is the amount of acid or alkali that have to be added into 1 L of whole blood to balance blood pH to be 7.4 in PaCO 2 40 mmHg.…”

“…9,10 Alternative method (Stewart) is difficult to apply because it has many variables that have to be measured and calculated so the experts developed a simplified Stewart method including Fencl-Stewart and Figge-Stewart. 6,11,12 Fencl-Stewart method calculates BDE gap based on Na + , Cland albumin concentrations. Figge-Stewart method calculated SIG (the difference between apparent SID/ SIDa and effective SID/SIDe) showing there are other unmeasured strong ions.…”