Acid Base Work Book 2019 Section One 1. Medical student draws ABG and put it in her pocket for 6 hours. Then she sends it to the lab. Normal Values Case 7.35-7.45 pH 7.26 40 pCO2 61 140 Na 138 4 K 3.8 80-26 = 54 = 24 x 61/31 = 47. 54=/= 47. Not valid. Redraw labs. 100 Cl 100 24 HCO3 31 8-16 BUN 17 0.6-1.4 Cr 1.2 12 Anion Gap 2. 36 year old man with history of depression found down in his garage Normal Values Case 7.35-7.45 pH 7.28 40 pCO2 26 Acidemia. Metabolic, ingestion? 80-28 = 52 = 24x26/12 = 52 (valid) 140 Na 140 AG 25 - AGMA 4 K 3.9 pCO2 = 1.5 x 12 + 8 +/- 2 = 24-28 (pCO2 fits) - approp compensation 100 Cl 103 Delta gap/delta bicarb = 13/12 = 1.1 - pure AGMA 24 HCO3 12 8-16 BUN 10 AGMA with appropriate respiratory compensation 0.6-1.4 Cr 0.8 12 Anion Gap 3. 68 year old man with stable COPD in for routine PFT’s Normal Values Case 7.35-7.45 pH 7.34 40 pCO2 60 acidemia , resp? Stable and chronic? 140 Na 140 80-34 = 46 = 24 x 60/32 = 45 (valid) AG 10 4 K 3.9 pCO2 increases by 10 = bicarb increase by 3.5 100 Cl 98 60-40 = 20. 20/10 = 2. 2 x 3.5 = 7. 24 + 7 = 31 (approp met comp) 24 HCO3 32 Chronic respiratory acidosis with appropriate metabolic compensation 8-16 BUN 20 0.6-1.4 Cr 1.2 12 Anion Gap Acid Base Work Book 2019 4. 22 year old G2P1 woman in the 33rd week of pregnancy Normal Values Case 7.35-7.45 pH 7.46 Alkalemia. Chronic due to pregnancy? 40 pCO2 29 80-46 = 34 = 24 x 29/20 = 34 (valid) AG 10 140 Na 138 Decrease bicarb by 4 for every decrease in pCO2 by 10 4 K 3.7 40-29 = 11 24-20 = 20 100 Cl 108 Chronic respiratory alkalosis with metabolic compensation 24 HCO3 20 8-16 BUN 6 Cirrhotics get this for the same reason - progesterone increases respiratory drive/causes hyperventilation 0.6-1.4 Cr 0.5 12 Anion Gap 5. 18 year old wrester with recent rapid weight loss Normal Values Case 7.35-7.45 pH 7.50 40 pCO2 48 Alkalemia. Diuretics and contraction alkalosis? 140 Na 137 80-50 = 30 = 24 x 48/38 = 30 (valid) 4 K 3.2 pCO2 = 0.9 x 38 + 16 +/- 2 = 48-52 (pCO2 in this range) appropr 100 Cl 92 compensation 24 HCO3 38 Metabolic alkalosis with appropriate respiratory compensation 8-16 BUN 23 0.6-1.4 Cr 1.0 12 Anion Gap 6. In a man undergoing surgery, it was necessary to aspirate the contents of the upper gastro-intestinal tract. Normal Values Case 7.35-7.45 pH 7.50 40 pCO2 52 140 Na 140 alkalemia . metabolic. GI losses. 4 K 3.0 80-50 = 30 = 24 x 52/40 = 31 (valid) pCO2 = 0.9 x 40 +16 +/- 2 = 50-54 (within this range) approp comp 100 Cl 90 24 HCO3 40 Metabolic alkalosis with appropriate respiratory compensation 8-16 BUN 22 0.6-1.4 Cr 1.4 12 Anion Gap Acid Base Work Book 2019 7. A person was admitted to hospital in a coma. Normal Values Case 7.35-7.45 pH 7.10 40 pCO2 16 BAD acidemia. Ingestion! H+ = 40 x 1.25 x 1.25 x 1.25 = 78.125 = 24 x 16/5 = 80 (valid - see reference 140 Na 138 sheet for formula for pH less than 7.2) 4 K 3.7 AG 33 - AGMA 100 Cl 100 pCO2 1.5 x 5 + 8 +/- 2 = 13.5-17.5 ( pco2 within this range) appropr comp 24 HCO3 5 Delta gap/delta bicarb = 21/9 = 1.1 - pure AGMA 8-16 BUN 36 AGMA with appropriate respiratory compensation 0.6-1.4 Cr 0.5 12 Anion Gap 8. 39 year old man with heartburn Normal Values Case 7.35-7.45 pH 7.50 40 pCO2 50 Alkalemia. Too much tums 140 Na 141 80 - 50 = 30 = 24 x 50/37 = 32 (valid) 4 K 3.5 AG 12 100 Cl 92 pCO2 = 0.9 x 37 + 16 +/- 2 = 47-52 (pco2 in this range) - appropr comp 24 HCO3 37 Metabolic alkalosis with appropriate respiratory compensation 8-16 BUN 10 0.6-1.4 Cr 0.8 12 Anion Gap 9. Nurse gets blood gas because patient has been breathing hard for the past 3 hours. Normal Values Case 7.35-7.45 pH 7.46 40 pCO2 30 alkalemia . acute resp alk? 140 Na 134 80-30 = 50 =/= 24x 30/22 --may not be relevant in acute resp issue AG 12 4 K 4.1 Bicarb decreases by 2 for every decrease in pCO2 by 10 100 Cl 100 40-30 = 10 so 24-1 = 23 - close enough 24 HCO3 22 Acute respiratory alkalosis 8-16 BUN 22 0.6-1.4 Cr 1.4 12 Anion Gap Acid Base Work Book 2019 10. A 44 year old moderately dehydrated man was admitted with a two day history of acute severe diarrhea. Normal Values Case 7.35-7.45 pH 7.31 40 pCO2 33 Acidemia. Bicarb loss? 140 Na 134 80 - 31 = 49 = 24 x 33/16 = 49.5 (valid) 4 K 2.9 AG 10 NAGMA 100 Cl 108 pCO2 = 1.5 x 16 + 8 +/- 2 = 30-34 (within range) appropr comp 24 HCO3 16 NAGMA with appropriate respiratory compensation 8-16 BUN 31 0.6-1.4 Cr 1.5 12 Anion Gap 11. A 22 year old female with type I DM, presents to the emergency department with a 1 day history of nausea, vomiting, polyuria, polydypsia and vague abdominal pain. Exam noted for deep sighing breathing, orthostatic hypotension, and dry mucous membranes Normal Values Case 7.35- pH 7.27 7.45 Acidemia. ?DKA 40 pCO2 23 80-27= 53= 24 x (23/11) = 50 (valid) AG 26 140 Na 132 pCO2 = (1.5 x 11) + 8 +/- 2 = 22.5-26.5 (pCO2 within this range) 4 K 6.0 delta gap/ delta bicarb = 1.1 100 Cl 93 24 HCO3 11 pure AGMA with appropriate respiratory compensation 8-16 BUN 38 0.6-1.4 Cr 2.6 12 Anion Gap 12. A previously well 55 year old woman is admitted with a complaint of severe vomiting for 5 days. Physical examination reveals postural hypotension, tachycardia, and diminished skin turgor. The laboratory finding include the following. Normal Values Case 7.35-7.45 pH 7.23 Acidemia. ?lactic acidosis? 40 pCO2 22 80 – 23 = 57 = 24 x 22/9 = 58 (valid) AG 54 140 Na 140 pCO2 = 1.5 x 9 +8 +/- 2 = 19.5 – 23. 5 (pCO2 within range) 4 K 3.4 delta gap/delta bicarb = 2.8 100 Cl 77 24 HCO3 9 pure AGMA with respiratory compensation with concomitant metabolic 8-16 BUN 48 alkalosis 0.6-1.4 Cr 2.1 12 Anion Gap Acid Base Work Book 2019 13. A 70 year old man with history of CHF presents with 6 days of shortness of breath and leg swelling. Normal Values Case 7.35-7.45 pH 7.30 40 pCO2 60 acidemia. 80 – 30 = 50 = 24 x 60/30 = 48 (valid) 140 Na 140 AG 9 4 K 4.0 ?Chronic? 6 days. 100 Cl 101 60 – 40 = 20. 20/10 = 2. 2 x 3.5 = 7. 24 + 7 = 31 (compensated bicarb for 24 HCO3 30 pco2 of 60) 8-16 BUN 21 Chronic respiratory acidosis with appropriate metabolic compensation 0.6-1.4 Cr 1.0 12 Anion Gap 14. A 50 year old insulin dependent diabetic woman was brought to the ED by ambulance. She was semi-comatose and had been ill for several days. Normal Values Case 7.35-7.45 pH 7.41 nl pH. Mixed? 40 pCO2 32 80 – 41 = 39 = 24 x 32/19 = 40 (valid) AG 34 - AGMA 140 Na 132 1.5 x 19 + 8 +/- 2 = 34.5 – 38.5 (pCO2 too low) – resp alk 4 K 2.7 Delta gap/delta bicarb = 22/5 = 4.4 – met alk 100 Cl 79 AGMA with respiratory alkalosis with concomitant 24 HCO3 19 metabolic alkalosis 8-16 BUN 30 0.6-1.4 Cr 2.1 12 Anion Gap 15. A 19 year old pregnant insulin dependent diabetic patient was admitted with a history of polyuria and thirst. She now felt ill and presented to hospital. Normal Values Case Nl pH. Mixed? 7.35-7.45 pH 7.39 80-39 = 41 = 24 (16/10) = 38.4 (valid) 40 pCO2 16 AG 25 – AGMA 140 Na 136 4 K 4.8 pCO2 = 1.5 x 10 + 8 +/- 2 = 21 – 25 (pCO2 too low) – resp alk 100 Cl 101 delta gap/ delta bicarb = 13/14 = 1 – pure AGMA 24 HCO3 10 8-16 BUN 28 0.6-1.4 Cr 2.2 pure AGMA with concomitant respiratory alkalosis 12 Anion Gap Acid Base Work Book 2019 16. 72 year old woman taking oil of wintergreen, Bayer and ECASA for pain, fever, and heart. Normal Values Case Nl pH. Mixed? 7.35-7.45 pH 7.38 40 pCO2 26 80- 38 = 42 = 24 x 26/15 = 42 (valid) 140 Na 141 AG 25 – AGMA 4 K 4.0 1.5 x 15 + 8 +/- 2 = 28.5-32.5 (pCO2 too low) – resp alk 100 Cl 101 24 HCO3 15 Delta gap / delta bicarb = 13/9 = 1.4 – pure AGMA 8-16 BUN 17 0.6-1.4 Cr 0.8 AGMA with concomitant respiratory alkalosis 12 Anion Gap 17.