Fencle versus Kellum Please install office XP to enable animation

PENDAHULUAN Diagnosis (& prognosis) of acid-base disorders ------guide fluid therapy Explain the role of strong ions on pH Elaborate the influences of metabolic component of acid-base disorders (masking effect of hypoalbuminemia, phosphate in ARF) Detect and calculate UA (unmeasured anion) Perform synergistically with ventilatory & hemodynamic support

HH vs Stewart Determinant pH: pCO2 & HCO3 SBE (standard base excess) corrected AG AG + [0.25 x (44 - albumin)] Determinant pH:pCO2, SID, ATOT UA effect (Fencle-Stewart) SIG = AG – A- SIG = SIDa –SIDe (menghitung UA) Lain-lain: Tidak dikenal istilah asidosis hiperkloremik, asidosis dilutional,alkalosis kontraksi, alkalosis hipoalbuminemik Lain-lain: Dikenal istilah asidosis hiperkloremik, asidosis dilutional,alkalosis kontraksi, alkalosis hipoalbuminemik

Peter Stewart (1921-1993) JA Kellum Vladimir Fencl (1923-2002)

Fencle & Kellum Fencle-Stewart JA Kellum Directly measures the amount of UA Measure the effect of UA on base excess Values more negative than -6 mEq/L suspect the presence of UA

BASE EXCESS DAN STEWART BE =The amount of acid or alkali to add to a blood sample (whole blood) in vitro to reverse the pH to 7.40, while pCO2 being maintained at 40 mmHg. Fencl - Stewart Approach measures the effect of UA on base excess also called BEUA

BASE EXCESS & STEWART BE measured by machine (or HCO3- - 24 + 11.6*(pH - 7.4) ) SID effect, mEq/l = A + B A. Free Water effect on Na+ = 0.3 x ([Na+] – 140) B. Corrected Cl- effect = 102 – ([Cl-] x 140/[Na+]) ATOT effect, mEq/l = 0.123 x pH - 0.6310 x (42 - [Albumin]) UA effect = BE ef – SID ef – ATot ef Story DA, Bellomo R. Strong ions, weak acids and base excess: a simplified Fencl–Stewart approach to clinical acid–base disorders British Journal of Anaesthesia, 2004, Vol. 92, No. 1 54-60

Case 1 BE -4 SID effect, mEq/l = A + B A. Free Water effect on Na+ Fencle-Stewart Case 1 pH 7.2/ pCO2 25/ BE -4/ HCO3- 10 Na+160 ;Cl- 102 ;K+ 5 ;Alb 3.7 BE -4 SID effect, mEq/l = A + B A. Free Water effect on Na+ = 0.3 x ([160] – 140)=6 B. Corrected Cl- effect = 102 – ([C102-] x 140/[160])=12.75 ATOT effect, mEq/l = 0.123 x 7.2 - 0.6310 x (42 - [37])=1.273 UA effect = BE ef – SID ef – ATot ef= -4 -(6 +12.75+ 1.273)=-24.023

SID effect (free water effect + chloride effect 19.75) BASE EXCESS & STEWART Fencle-Stewart SID effect (free water effect + chloride effect 19.75) 160 Na HCO3- SID i SID effect 19.75 (alkalinisasi) 142 UA Na UA effect -24.023 Albumin effect 1.273 (alkalinisasi) Alb Alb Primary metabolic acidosis, with increased anion gap, mixed with a metabolic alkalosis, with full respiratory compensation Na+ Cl-

UA effect = 10 – [(3) + (6.8) + (0.5)] mEq/L = - 0.3 Fencle-Stewart Case 2: 7.48 / 45 / +10 / 34 Na 150; Cl 102; Alb 4 (a) Free water effect: 0.3 x (150-140) = 3 (b) Chloride effect 102-(102 x 140/150) = 6.8 (c) Albumin effect (0.123 x 7.48 - 0.631) (42-[40]) = 0.578 UA effect = 10 – [(3) + (6.8) + (0.5)] mEq/L = - 0.3

BASE EXCESS & STEWART 150 140 Primary metabolic alkalosis, Fencle-Stewart BASE EXCESS & STEWART Alkalizing effect of HyperNa+ +10  BE +9.8 150 HCO3- 140 Alb Alb Primary metabolic alkalosis, with full respiratory compensation Na+ Cl-

UA effect = 9 – [(0) + (9) + (0)] mEq/L = 0 Fencle-Stewart Case 3: 7.48 / 45 / + 9 / 34 Na 140; Cl 93; Alb 4.2 (a) Free water effect: 0.3 x (140-140) = 0 (b) Chloride effect 102-(93 x 140/140) = 9 (c) Albumin effect (0.123 x 7.25 - 0.631) (42-[42]) = 0 UA effect = 9 – [(0) + (9) + (0)] mEq/L = 0

Alkalizing effect of Hypochloremia Fencle-Stewart BASE EXCESS & STEWART Alkalizing effect of Hypochloremia +9  BE +9 140 HCO3- 102 Alb Alb 93 Na+ Cl-

UA effect = -4 – [(0) + (0) + (6.3)] mEq/L = -10.3 Fencle-Stewart Case 4: 7.35 / 35 / -4 / 15 Na 140; Cl 102; Alb 2.0 (a) Free water effect: 0.3 x (140-140) = 0 (b) Chloride effect 102-(102 x 140/140) = 0 (c) Albumin effect (0.123 x 7.35 - 0.631) (42-[20]) = 6.0071 UA effect = -4 – [(0) + (0) + (6.3)] mEq/L = -10.3

BASE EXCESS DAN STEWART Fencle-Stewart BASE EXCESS DAN STEWART BE due to  Alb  + 6.0071 140 SID BE due to hypoalbuminemia UA- (10.3) Alb Hipoalb Na+ Cl-

Hipoalbuminemia SIDe =31.5 HCO3- 26 Na+ 137 Cl- 112 KATION ANION pH 7.36/pCO2 46/ BE 0.96/HCO3 26 Na+ 137; Cl- 112, Alb 20 g/L; Hb 8 g /dl Mg++ 1 HCO3- 26 Ca++ 2.2 K+ 3.5 SIDe =31.5 25 3.5 3.2 Na+ 137 Weak acid (Alb- 20,P- 1) Cl- 112 When these patients have a normal pH and a normal SBE and HCO3- concentration, it would seem most appropriate to consider this to be physiologic compensation for a decreased ATOT rather than classifying this condition as a complex acid–base disorder with a mixed metabolic acidosis/ hypoalbuminemic alkalosis Stewart's designation of a 'normal' SID of approximately 40 mmol/l was based on a 'normal' CO2 and ATOT The 'normal' SID for a patient with an albumin of 2g/dl would be much lower (eg approximately 32 mmol/l). John A Kellum Determinants of blood pH in health and disease Critical Care 2000, 4:6-14  KATION ANION SIDa = (137 + 3.5 + 2.2 +1) – 112 = 31.7 SIDe= 26 + 0.2x[20] + 1.5 x [1]

7.42 / 35 / -1.86 / 22 ; Interpreted by H-H  normal Fencle-Stewart Case 5 (severe sepsis): 7.42 / 35 / -1.86 / 22 ; Interpreted by H-H  normal (a) Free water 0.3 x (140-140) = 0 (b) Chloride effect 102-(102 x 140/140) = 0 (c) Albumin effect (0.123 x 7.42 - 0.631) (42-[18]) = 6.7 UA effect = - 1.86 – [(0) + (0) + (6.7)] mEq/L = - 8.56 Catatan: Nilai K, Ca & Mg tidak ditampilkan Na+ 140; K+ 3.5 Cl- 102; Alb 1.8

BASE EXCESS DAN STEWART 140 SIDe  30.84 Acidifying effect of lactate  - 8.56 UA = - 8.56 Alkalizing effect of hypoalb  + 6.7 Alb 102 hipoalbumin Na+ Cl-

J.A. KELLUM Directly measures the amount o f UA

Kasus 6. Pasien cardiac arrest,CPR, hypoxic encephalopathy pH 7 Kasus 6. Pasien cardiac arrest,CPR, hypoxic encephalopathy pH 7.55; Na+ 159 mEql/L ;K + 3.6 mEql/L; Cl- 121 mEq/L ;Ca + + 4.2 mEq/L;Mg + + 2.2 mEq/L; PO4 0.85 mg/dl; Alb 9 g/L; PCO2 29 mmHg; HCO3 25.5 mEq/L; BE 3 Apakah jenis kelainan asam-basa pasien ini? Langkah: 1. Untuk menghitung ATOT,harus dicari nilai Pi (dalam mEq/L) dari PO4 dan albumin Dikonversi menjadi mEq/L dg rumus. Pi = (PO4 x10/30.97)x(0.309xpH-0.469) = (0.85 x 10/30.97) x 0.309 x 7.55 -0.469) = ~ 0.5 mEq/L Albumin = Alb x(0.123 x pH-0.631) = 9 x(0.123 x 7.55 – 0.631) = 2.67885 mEq/L 2. Hitung SIDa = Na+ + K+ Ca++ + Mg++ - Cl = 48 mEq/L 3. Hitung SIDe = HCO3- + Pi + Albumin = 28.69 mEq/L 4 UA (unmeasured anion) = SIDa- SIDe = 19.31

Kasus 6. Pasien cardiac arrest,CPR, hypoxic encephalopathy pH 7 Kasus 6. Pasien cardiac arrest,CPR, hypoxic encephalopathy pH 7.55; Na+ 159 mEql/L ;K + 3.6 mEql/L; Cl- 121 mEq/L ;Ca + + 4.2 mEq/L;Mg + + 2.2 mEq/L; PO4 0.85 mg/dl; Alb 9 g/L; PCO2 29 mmHg; HCO3 25.5 mEq/L; BE 3 Ca++ 4.2 HCO3- 25.5 Mg++ 2.2 K+ 3.6 Penurunan SID ~10 dikacaukan oleh efek dari UA yang tinggi(menurunkan SID). Defisit air plasma (Na 159 mEq/L) meningkatkan SID. Low SID acidosis diselubungi oleh hipoalbuminemia. BE luput mendeteksi asidosis dg UA tinggi dan menginterpretasi status asam basa hanya sebagai alkalosis metabolik ringan.HCO3 high normal. SIDe (28.67) Na+ 159 SIDa (50.6) ATOT Alb 2.67885 Pi 0.5 SIG =(UA) = SIDa –SIDe = 19.31 121

JA Kellum Case 7. Patient with multiple trauma, followed by ARDS and sepsis pH 7.32; Na+ 131 mEql/L ;K + 4.2 mEql/L; Cl- 86 mEq/L ;Ca + + 3.6 mEq/L;Mg + + 2.2 mEq/L; PO4 4 mg/dl; Alb 8 g/L; PCO2 41 mmHg; HCO3 21 mEq/L; BE -4.2 What is the acid-base profile of this patient? Approach: 1. To calculate ATOT,you have to determine Pi (in mEq/L) from PO4 and albumin converted to mEq/L by the following formulas. Pi = (PO4 x10/30.97)x(0.309xpH-0.469) = (4 x 10/30.97) x 0.309 x 7.32 -0.469) = ~ 2.3 mEq/L Albumin = Alb x(0.123 x pH-0.631) = 8 x(0.123 x 7.32 – 0.631) = 2.15488 mEq/L 2. Calculate SIDa = Na+ + K+ Ca++ + Mg++ - Cl = 55 mEq/L 3. Calculate SIDe = HCO3- + Pi + Albumin = 25.454 mEq/L 4 UA (unmeasured anion) = SIDa- SIDe = 29.55

JA Kellum Case 7. Patient with multiple trauma, followed by ARDS and sepsis pH 7.32; Na+ 131 mEql/L ;K + 4.2 mEql/L; Cl- 86 mEq/L ;Ca + + 3.6 mEq/L;Mg + + 2.2 mEq/L; PO4 4 mg/dl; Alb 8 g/L; PCO2 41 mmHg; HCO3 21 mEq/L; BE -4.2 Ca++ 3.62 HCO3- 21 Mg++ 2.2 SIDe (25,454) K+ 4.2 SIDa (55) Na+ 131 ATOT Alb 2.15488 Pi 2.3 SIG =(UA) = SIDa –SIDe = 29.55 86 SID decreased by ~ 12 mEq/L (owing to water excess and high UA and Pi. This acidosis was masked by alkalosis due to Cl deficit and hypoalbuminemia; HCO3 onlu slightly decreased. Base deficit was only - 4 mEq/L Here, the severity of acidosis had been underestimated.

Thank YOU