Lab values beyond the numbers

1. Lab values beyond the numbers Toni Petrillo, MD

2. Objectives • Ability to interpret a blood gas • Recognition of abnormal Lab values • Treatment of some of the more critical values

3. Overview • Blood Gases • Chemistries • CBC’s • CSF

4. Blood Gases • pH • PCO2 • PO2 • Base Excess • O2 Sat

5. Blood Gases • pH • Normal : 7.35 - 7.45 • pH = acidosis; • pH = alkalosis

6. Blood Gases • PCO2 • Normal 35-45mmHg • Increased PCO2 • Respiratory Acidosis • Compensated metabolic alkalosis • Decreased PCO2 • Respiratory Alkalosis • Compensated metabolic acidosis • PO2 • 80-100mmHg at sea level and RA

7. Blood Gases • Base • Normal -3 to +3mMol/L • Base excess indicates too much (metabolic alkalosis) • Base deficit indicates too little buffer (metabolic acidosis)

8. Blood Gases: Metabolic Acidosis • Metabolic Acidosis • for every drop of meq/l in HCO3 pH will decrease by 0.15 • if respiratory compensation will have a in PCO2

9. Blood Gases: Metabolic Acidosis • Causes • Renal losses of HCO3 • GI Losses of HCO3 • Uremia • DKA • Ingestion • Aspirin • ETOH

10. Blood Gases: Respiratory Acidosis • PCO2 increased • PCO2 by 10mmHg will PHbyunits • If metabolic compensation occurs will have HCO3 • Causes • Brain Depression: sedative, CHI • Neuromuscular : Myasthenia, Gullian Barre • Lungs: Pulmonary Edema, FB, Pneumonia, Pneumothorax, atelectasis • Other: Abdominal distention

11. Blood Gases: Metabolic Alkalosis • HCO3 increases • for every  meq/L will  pH by 0.15 units • If respiratory compensation PCO2 • Related to conditions that have hypokalemia or loss of hydrogen Ion • Causes • Hypokalemia • GI: vomiting, Pyloric stenosis • Urine Loss: diuretics, antibiotics, Mg

12. Blood Gases: Metabolic Alkalosis • Causes cont • Loss Of H+ • vomiting • Hypercalcemia • chloride losing diarrhea

13. Blood Gases: Respiratory Alkalosis • PCO2  • For every PCO2 mmHg pH 0.08 • If metabolic compensation  HCO3 • Caused by excessive removal of CO2

14. Blood Gases: Respiratory Alkalosis • Causes • Respiratory Center Stimulation • CNS (tumor, Infection) • Anxiety/Stress • Drugs • Hypermetabolic States • Fever • Thyroid • Mechanical Ventilation

15. Blood Gases: Examples • 7.56 / 20/ 88/ -2 • 7.24/ 60/ 88/+2 • 7.55/ 40/88/ +15 • 7.12/ 40 /88 / -20

16. Blood Gases: Examples • 7.30 / 60 / 88 / + 20 • 7.20/ 15 / 88/ -25

17. Chemistries (Basics) • Sodium (Na+) • Potassium (K+) • Chloride (Cl-) • Bicarb (HCO3-) • BUN • Creatinine (Cr) • Glucose • Calcium (Ca+)

18. Chemistries: Na+ • Sodium • Normal range 135-145mmol/L • Life threatening • < 120 • >155 • Can cause seizures, venous sinus thrombosis, CNS hemorrhage,

19. Hyponatremia Excessive H2O Cirrhosis, CHF Hypoalbuminemia Nephrotic Malnutrition Vomiting/ Diarrhea Diuretics SIADH Cerebral Salt Wasting False Hyperglycemia Na+ decrease 1.6 meq/l for each increase in glucose over 100 hyperlipidemia Na decrease by .002 x lipid (mg/dl Chemistries : Na+

20. Chemistries : Na+ • Hypernatremia • Diabetes Insipidus • Diarrhea • Dehydration • Hypercalciuria • Diabetes • Hyperaldosteronism

21. Chemistries : Na+ • Treatment is based partially on the causes • if hypernatremic do not want to correct Na+ more than 10-15 meq per day • will increase risk of cerebral edema • 3-4 cc/kg of free water will decrease serum Na+ by 1 Meq/L • for acute symptomatic hyponatremia may use hypertonic saline 5-10 cc /kg

22. Chemistries: K+ • Potassium • Normal 3.4 - 4.7mmol/L • Life threatening • < 2.5 • >6.5 • Major complications Arrhythmia and EKG changes, weakness

23. Hypokalemia Diuretics hypomagnesium Licorice RTA V/D Pyloric Stenosis DKA Antibiotics (ie: AmphoB) Hyperkalemia Acidosis Renal Failure Muscle necrosis Blood Transfusions Hemolysis CAH Chemistries: K+

24. Hyperkalemia peaked T waves Widening of QRS loss of P wave ST segment depression bradycardia ventricular arrhythmias Hypokalemia prominent u wave ST segment depression ventricular arrhythmias Chemistries: K+ and changes in EKG

25. Treatment of Hypokalemia: KCL bolus 0.3 - 1 meq / kg no more than 0.6 meq/kg/hour Treatment of Hyperkalemia: Insulin and Glucose NaHco3 Ca+ Kayexalate Lasix Albuterol Chemistries: K+

26. Chemistries: Cl - • Chloride • Normal 95-105mEQ/L • Hypochloremia • Metabolic Alkalosis Respiratory Acidosis • CHF •Burns • Hyperchloremia • Metabolic Acidosis •Respiratory Alkalosis • Dehydration •RTA

27. Chemistries: HCO3- • Sodium Bicarbonate • Normal: 20-26 mEQ / L • Increased in Metabolic Alkalosis and Compensated Respiratory Acidosis • Decreased in Metabolic Acidosis and Compensated Respiratory Alkalosis • Causes previously discussed in blood gas section

28. Chemistries: BUN • Blood Urea Nitrogen • Normal: 5-20 mg/dl • Elevated Tissue Necrosis • Gi Bleed •High Protein Diet •Steroids • Shock •Dehydration •Diarrhea • Burns •Tissue Necrosis • Decreased • Anabolic Steroids •Malnutrition • Liver Dz •Pregnancy

29. Chemistries: Cr • Creatinine • Normal: Child usually less than 1 • Increased: • Renal Dz • Muscle necrosis • hypovolemia

30. Chemistries: Glucose • Glucose • Normal: 60-115mg/dl (infants >40) • Hyperglycemia (AMS, Kusmal breathing) • diabetes •Pancreatitis • Cushing's dz •Pheochromocytoma • drugs (ie: Steroids, Epi) • Hypoglycemia (jitters, Sz, Sweating) • Malaria •liver dz •Malignancy • enzyme deficiency •Malnutrition

31. Chemistries: Glucose • Treatment of Hypoglycemia • Neonate or child: 0.5 to 1 gram / kg • if using D25 would be 2-4 cc / kg • dilute D50 1:1 with sterile water • if using D10 5-10 cc / kg • dilute D50 1:4 • Adult: ampule of D50

32. Chemistries: Glucose • Treatment of Hyperglycemia • Fluid bolus 10cc/kg NS • insulin 0.05u - 1 unit/kg • If diabetic in DKA be very judicious of fluid administration and no NHCO3 unless cardiac instability

33. Chemistries: Ca+ • Calcium • Normal 8-11mg/dl • Panic Value:<7 or > 12 (tetni, Sz, arrhythmia) • Hypercalcemia (CHIMPS) • C= Cancer • H= Hyperthyroid • I= Iatrogens • M= Multiple Myeloma • P= Primary Hyperparathyroid • S= Sarcoid

34. Chemistries: Ca+ • Hypocalcemia • renal failure • hypoparathyroid • pseudohypoparathyroid • magnesium deficiency • anticonvulsants • Rickets • Pancreatitis • Blood transfusions

35. CBC’S • White Blood cell = WBC • Differential • Segs / polys •Lymphocytes • Eosinophils •Monocytes • Basophils •Bands • Hemoglobin • Hematocrit • Platelets

36. CBC: WBC

37. Increased neutrophils physiologic newborn,pregnancy Pathologic acute infection inflammatory dz metabolic disorder tissue necrosis drugs stress Decreased neutrophils Infection bacterial typhiod septicemia Viral Hepatitis –mono flu –measles myeloid hypoplasia drugs CBC: WBC

38. Increased Lymphocytes Infection Viral: Hepatitis –mono CMV –HSV Bacterial Pertussis –mumps Chronic Inflammation Metabolic Hematologic ALL Decreased Lymphocytes Increased Corticosteroids immunodeficiency miliary Tb Lupus CBC: WBC

39. CBC: WBC • Monocytes • Elevated • mumps • malaria • lymphomas • Eosinophils • Elevated • Parasitic dz •T-Cell leukemia • allergies •lupus

40. CBC: Hemoglobin / Hematocrit • Hemoglobin • Normal • 1 week: 13-20 •1 month: 11-17 • 6months 10.5-14.5 •1 year: 11-15 • 10years: 11-16 •15years: 14-18M 12-16F • Hematocrit • Normal • 14-90d:35-49 •6m-1yr:30-40 • 4-10yr: 31-43 •Adult:42-52M 37-47F

41. Increased Hct Polycythemia Heart Dz Chronic Hypoxia High Altitude Hemoconcentration Surgery Burns Dehydration Decreased Hct Anemia Iron Deficiency Malabsorbtion HgSS Toxin/drugs Lead Infection Malaria CMV Cancer CBC: H/H

42. CBC: Platelets • Platelets • Normal: 150-450 thousand • Decreased platelets • Decreased production • Marrow Depression: Aplastic Anemia, Radiation • Marrow infiltration: Leukemia • Congenital: Wiskott Aldrich, immune deficiencies • Increased destruction • autoimmune: ITP, Mono, SLE • Coagulopathies: DIC, HUS, TTP • Drugs

43. CBC: Platelets • Increased Platelets • Reactive thrombocytosis • infection • splenectomy • surgery/stress • Inflammatory dz. • Thrombocythemia • myeloproliferative disorder • Chronic granulocytic leukemia

44. CSF