Introduction to Vital Signs and Basic Laboratory Tests Joel N. Kniep, M.D. Dept. of Pathology

Objectives Introduce vital signs and their use in clinical practice Introduce basic laboratory tests and their use in clinical practice Discuss normal values and test interpretation

Clinical Vital Signs (Vitals) Temperature Pulse rate Respiration rate (RR) Blood pressure (bp)

Temp Measure of body’s core temp (temp of internal organs) –in ° F (or ° C) –Locations: oral, rectum, axilla, ear –Rectal = 0.5 – 0.7° F higher than oral temp –Axilla = 0.3 – 0.4° F lower than oral temp Normal: 97.8 – 99° F (36.5 – 37.2° C) Critical: > 98.6° F orally or 99.8° F rectally (pyrexia [fever]); < 95° F (hypothermia)

Pulse rate Heart rate (HR) or number of heart beats/min Normal: 60 – 100/min ↑ (tachycardia): ↑ Na + intake, ↓ Na + loss, Excessive free body H 2 O loss ↓ (bradycardia): ↓ Na + intake, ↑ Na + loss, ↑ free body H 2 O

RR Number of breaths/min –At rest –Also note breathing effort or difficulty Normal: 15 – 20/min Critical: 25 ↑ (hyperventilation): ↑ Na + intake, ↓ Na + loss, Excessive free body H 2 O loss ↓ (hypoventilation): ↓ Na + intake, ↑ Na + loss, ↑ free body H 2 O

Bp Measures the force of blood against the arterial vessel walls –Measured while seated, after resting for 5 mins, arm heart level (if possible) –Reported as a fraction (systolic/diastolic) & consists of 2 separate measurements: Systolic – pressure within artery during cardiac contraction Diastolic – pressure within artery during cardiac relaxation and filling Normal: < 120 mm Hg systolic and < 80 mm Hg diastolic Critical: > 220 mm Hg systolic or > 125 mm Hg diastolic ↑ (hypertension [htn]): ↑ Na + intake, ↓ Na + loss, Excessive free body H 2 O loss ↓ (hypotention): ↓ Na + intake, ↑ Na + loss, ↑ free body H 2 O

Complete Blood Count (CBC) Provides information on cellular components of blood Includes RBC count, Hemoglobin (Hgb), Hematocrit (Hct), RBC indices, White blood cell (WBC) count and differential, Platelet count

Total WBCs (leukocytes) Measurement of total WBC count –Consists of total # of WBCs/mm 3 of peripheral venous blood –Part of “routine” testing –Useful for evaluation of infection, neoplasm, allergy & immunosuppression Normal: 4,000 – 10,000/mm 3 Critical: 30,000/mm 3 ↑ (leukocytosis): infection, malignancy, trauma, stress, hemorrhage, tissue necrosis, inflammation, dehydration, thyroid storm ↓ (leukopenia): drug toxicity, bone marrow failure, overwhelming infections, dietary deficiency, congenital marrow aplasia, bone marrow infiltration, autoimmune disease, hypersplenism

Erythrocyte count (RBC) Measures # of circulating RBCs/mm 3 of peripheral venous blood –Direct measure of RBC count –Part of “routine” testing and anemia evaluation Normal: 3.5 – 5.5 x 10 6 /μL ↑: erythrocytosis, congenital heart disease, severe COPD, polycythemia vera, severe dehydration, hemoglobinopathies ↓: anemia, hemoglobinopathy, hemorrhage, bone marrow failure, renal disease, leukemia, prosthetic valves, normal pregnancy, multiple myeloma, Hodgkin disease, lymphoma, dietary deficiency

Hgb Measures total amount of Hgb in blood –Indirect measure of RBC count –Part of “routine” testing and anemia evaluation Normal: 12 – 15 g/dL Critical: 20 g/dL ↑: erythrocytosis, congenital heart disease, severe COPD, polycythemia vera, severe dehydration ↓: anemia, hemoglobinopathy, hemorrhage, bone marrow failure, renal disease, leukemia, prosthetic valves, normal pregnancy, multiple myeloma, Hodgkin disease, lymphoma, dietary deficiency

Hct Measure of RBC percent of total blood vol –Indirect measure of RBC # & volume –Part of “routine” testing and anemia evaluation Normal: 36 – 48% Critical: 60% ↑: erythrocytosis, congenital heart disease, severe COPD, polycythemia vera, severe dehydration ↓: anemia, hemoglobinopathy, hemorrhage, bone marrow failure, renal disease, leukemia, prosthetic valves, normal pregnancy, multiple myeloma, Hodgkin disease, lymphoma, dietary deficiency

RBC indices Measures size and hgb content of RBCs Used to classify anemias Includes Mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), red blood cell distribution width (RDW)

MCV Measure of average volume/size of single RBC –MCV = Hct (%) x 10/RBC (million/mm 3 ) –Useful in anemia classification Normal: 80 – 100 mm 3 ↑ (macrocytic): pernicious anemia (vit B 12 deficiency), folic acid deficiency, antimetabolic therapy, alcoholism, chronic liver disease, hypothyroidism Normocytic: bone marrow failure/replacement, acute blood loss, chronic diseases, hemolytic anemias ↓ (microcytic): Fe deficiency anemia, thalassemia, anemia of chronic illness

MCH Measure of average amount of hgb within a single RBC –MCH = Hgb (g/dL) x 10/RBC (million/mm 3 ) –Provides little additional info to other indices Normal: 24 – 32 pg ↑: macrocytic anemias ↓: microcytic anemia, hypochromic anemia

MCHC Measure of average [hgb] within a single RBC –MCHC = Hgb (g/dL) x 100/Hct (%) –37 g/dL = maximum Hgb able to fit into an RBC (cannot be hyperchromic) Normal (normochromic): 32 – 36 g/dL ↑: spherocytosis, intravascular hemolysis, cold agglutinins ↓ (hypochromic): Fe deficiency anemia, thalassemia

RDW Measure of variation of RBC size (indicator of degree of anisocytosis) –Useful in anemia classification Normal: variation of 11.5 – 16.9% ↑: Fe deficiency anemia, vit B 12 or folate deficiency anemia, hemoglobinopathies, hemolytic anemias, posthemorrhagic anemias

Platelet count Measurement of platelets (thrombocytes) –Consists of actual # of platelets/mm 3 of peripheral venous blood –Part of “routine” testing –Useful for evaluation of petechiae, spontaneous bleeding, increasingly heavy menses or thrombocytopenia –Useful for monitoring discourse/therapy of thrombocytopenia/bone marrow failure Normal: 150,000 – 400,000/mm 3 Critical: 1,000,000/mm 3 ↑ (thrombocytosis): malignant disorders, polycythemia vera, postsplenectomy syndrome, rheumatoid arthritis, Fe deficiency anemia ↓ (thrombocytopenia): Hypersplenism, hemorrhage, immune thrombocytopenia, leukemia & other myelofibrosis disorders, TTP, DIC, SLE, chemotherapy, pernicious anemia

WBC definitions Leukocytosis – abnormally large number of leukocytes; generally indicated by WBC count of ≥ 10,000 cells/mm3 Lymphocytosis – form of actual or relative leukocytosis due to increase in numbers of lymphocytes Left shift – increase in the number of immature neutrophils (bands/stabs) found in the blood

WBC differential Measurement of percentage of each WBC type in specimen –Useful for infection, neoplasm, allergy & immunosuppression evaluations Normal: Neutrophils (50 – 70%), Lymphocytes (20 – 40%), Monocytes (2 – 8%), Eosinophils (0 – 5%), Basophils (0 – 2%) ↑: refer to individual cell types on chart ↓: refer to individual cell types on chart

Basic Metabolic Panel (BMP) Measures electrolytes, chemicals, metabolic end products & substrates Consists of Glucose, Blood Urea Nitrogen (BUN), Creatinine, Na +, K +, Cl -, Bicarbonate (HCO 3 - ), Ca 2+

Glucose Direct measure of blood glucose –Commonly used to evaluate diabetic pts –Part of “routine” testing Normal: mg/dL Critical: 400 mg/dL (♂) or 400 mg/dL (♀) ↑ (hyperglycemia): DM, acute stress response, Cushing syndrome, pheochromocytoma, chronic renal failure, acute pancreatitis, acromegaly, corticosteroid therapy ↓ (hypoglycemia): insulinoma, hypothyroidism, hypopituitarism, Addison disease, extensive liver disease, insulin overdose, starvation

BUN Measures urea nitrogen in blood –End product of protein metabolism (produced in liver) –Indirect measure of renal function & glomerular function (excretion) –Measure of liver metabolic function –Part of routine labs –Usually interpreted along with Cr (less accurate than Cr for renal disease) Normal: mg/dL Critical: > 100 mg/dL ↑: prerenal causes, renal causes, postrenal azotemia ↓: liver failure, overhydration because of SIADH, neg nitrogen balance, pregnancy, nephrotic syndrome

Creatinine Measures serum creatinine –Catabolic product of creatine phosphate (skeletal muscle contraction) –Excreted entirely by kidneys → direct measure of renal function –Minimally affected by liver function –Elevation occurs slower than BUN –Doubling ≈ 50% reduction in GFR Normal: 0.44 – 1.03 mg/dL Critical: > 4 mg/dL ↑: diseases affecting renal function (glomerulonephritis, pyelonephritis, ATN, urinary tract obstruction, reduced renal blood flow, diabetic nephropathy, nephritis), rhabdomyolysis, acromegaly, gigantism ↓: debilitation, decreased muscle mass

Na + Measures serum sodium level –Major cation in EC space –Balance between dietary intake and renal excretion Normal: 136 – 146 mEq/L Critical: 160 mEq/L ↑ (hypernatremia): ↑ Na + intake, ↓ Na + loss, Excessive free body H 2 O loss ↓ (hyponatremia): ↓ Na + intake, ↑ Na + loss, ↑ free body H 2 O

K+K+ Measures serum potassium level –Major cation within cell Normal: 3.4 – 5.2 mEq/L Critical: 6.5 mEq/L ↑ (hyperkalemia): excessive intake, acidosis, acute/chronic renal failure, Addison disease, hypoaldosteronism, infection, dehydration ↓ (hypokalemia): deficient intake, burns, hyperaldosteronism, Cushing syndrome, RTA, licorice ingestion, alkalosis, renal artery stenosis

Cl - Measures serum chloride level –Major anion in EC space –Helps maintain electrical neutrality; follows sodium Normal: 98 – 108 mEq/L Critical: 115 mEq/L ↑ (hyperchloremia): dehydration, metabolic acidosis, RTA, Cushing syndrome, renal dysfunction, respiratory alkalosis, hyperparathyroidism ↓ (hypochloremia): overhydration, SIADH, CHF, chronic respiratory acidosis, metabolic alkalosis, Addison disease, Aldosteronism, vomiting/prolonged gastric suction, hypokalemia

HCO 3 - Measures CO 2 content of blood –Major role in acid-base balance –Regulated by kidneys –Used to evaluate pt pH status & electrolytes Normal: 22 – 32 mEq/L Critical: < 6 mEq/L ↑: severe vomiting, high-volume gastric suction, aldosteronism, mercurial diuretic use, COPD, metabolic alkalosis ↓: chronic diarrhea, chronic loop diuretic use, renal failure, DKA, starvation, metabolic acidosis, shock

Ca 2+ Measures serum calcium level –Direct measurement –Used to evaluate parathyroid function & Ca metabolism –Used to monitor renal failure, renal transplantation, hyperparathyroidism, various malignancies, & Ca level when giving large-volume blood transfusions Normal: Total = 8.3 – 10.3 mg/dL, Ionized = 4.5 – 5.6 mg/dL Critical: Total 13 mg/dL, Ionized 7 mg/dL ↑ (hypercalcemia): hyperparathyroidism, bone mets, Paget disease of bone, prolonged immobilization, milk-alkali syndrome, vit D intoxication, hyperthyroidism ↓ (hypocalcemia): hypoparathyroidism, renal failure, rickets, vit D deficiency, osteomalacia, pancreatitis, alkalosis, malabsorption, fat embolism

Comprehensive Metabolic Panel (CMP) Includes all components of BMP plus Albumin, Total protein, Alkaline phosphatase (ALP), Alanine aminotransferase (ALT), Aspartate aminotransferase (AST) and Bilirubin

Albumin Measures amount of albumin in blood –Formed within liver & comprises 60% of total protein in blood –Maintains colloidal osmotic pressure & transports blood constituents –Measure of both hepatic function and nutritional state Normal: 3.5 – 5 g/dL ↑: dehydration ↓: malnutrition, pregnancy, liver disease, protein-losing enteropathies, protein-losing nephropathies, 3 rd space losses, overhydration, ↑ capillary permeability, inflammatory disease, familial idiopathic dysproteinemia

Total Protein Measures total protein in blood –Combination of prealbumin, albumin & globulins Normal: 6.4 – 8.3 g/dL

ALP Measures serum ALP concentration –Detect & monitor liver and bone disease Normal: units/L ↑: 1° cirrhosis, intrahepatic/extrahepatic biliary obstruction, 1°/metastic liver tumor, hyperparathyroidism, Paget disease, normal growing bones in children, bone mets, RA, MI, sarcoidosis, healing fracture, normal pregnancy, intestinal ischemia or infarction ↓: hypophosphatemia, malnutrition, milk-alkali syndrome, pernicious anemia, scurvy

ALT Found predominantly in liver –Injury/disease to parenchyma → release into blood –ID & monitor hepatocellular diseases of liver –If jaundiced, implicates liver rather than RBC hemolysis Normal: 4 – 36 international 37°C Sig ↑: hepatitis, hepatic necrosis, hepatic ischemia Mod ↑: cirrhosis, cholestasis, hepatic tumor, hepatotoxic drugs, obstructive jaundice, severe burns, trauma to striated muscle Mild ↑: myositis, pancreatitis, MI, infectious mono, shock

AST Found in highly metabolic tissue (cardiac & skeletal muscle, liver cells) –Disease/injury → lysing of cells & release into blood –Elevation proportional to # of cells injured –Used for evaluation of suspected coronary artery disease or hepatocellular disease Normal: 0 – 35 units/L ↑: heart diseases, liver diseases, skeletal muscle diseases ↓: acute renal disease, beriberi, DKA, pregnancy, chronic renal dialysis

Bilirubin Measures level of total bilirubin in blood –End product of RBC metabolism (RBCs → Hgb → Heme (+ globin) → Biliverdin → Bilirubin (unconjugated/indirect) → Bilirubin (conjugated/direct) –Component of bile –Consists of conjugated (direct) & unconjugated (indirect) bilirubin –Used to evaluate liver function; hemolytic anemia workup in adults & jaundice in newborns –Jaundice occurs when total bilirubin > 2.5 mg/dL Normal: 0.3 – 1 mg/dL Critical: > 12 mg/dL

Unconjugated bilirubin Measures level of indirect bilirubin in blood Normal: 0.2 – 0.8 mg/dL ↑: erythroblastosis fetalis, transfusion rxn, sickle cell anemia, hemolytic jaundice, hemolytic anemia, pernicious anemia, large-volume blood transfusion, large hematoma resolution, hepatitis, cirrhosis, sepsis, neonatal hyperbilirubinemia, Crigler-Najjar syndrome, Gilbert syndrome

Conjugated bilirubin Measures level of direct bilirubin in blood –Produced by conjugating glucuronide w/ unconjugated/indirect bilirubin in liver Normal: 0.1 – 0.3 mg/dL ↑: gallstones, extrahepatic duct obstruction, extensive liver mets, cholestasis from drugs, Dubin-Johnson syndrome, Rotor syndrome

Urinary Analysis (UA) Provides information about kidneys & other metabolic processes Used for diagnosis, screening & monitoring Frequently used to test for urinary tract infections (UTIs)

UA Normal Values Appearance: clear Color: amber yellow Odor: aromatic pH: 4.6 – 8 Protein: 0 – 8 mg/dL Specific gravity: – Leukocyte esterase: negative Nitrites: none Ketones: none

UA Normal Values cont. Bilirubin: none Urobilinogen: 0.01 – 1 Ehrlich unit/mL Crystals: none Casts: none Glucose: negative White Blood Cells: 0 – 4/low-power field WBC casts: none Red Blood Cells (RBCs): ≤ 2 RBC casts: none

Urinary Protein Used to monitor kidney function Normally not present in normal kidney due to size barrier in glomerulous Normally tested by dipstick method, quantification requires 24-hour urine collection Presence (proteinuria) can indicate nephrotic syndrome, multiple myeloma or complications of DM, glomerulonephritis, amyloidosis

Urinary Glucose Glucosuria – presence of glucose in urine –Reflection of serum glucose levels –Helpful in monitoring DM therapy –Renal glucose reabsorption threshold = 180 mg/dL (in proximal renal tubules) –Not always abnormal Can occur after a high-carbohydrate meal or IV dextrose fluids Can occur in diseases affecting renal tubules; genetic defects of metabolism & glucose excretion ↑: DM & other causes of hyperglycemia, pregnancy, renal glycosuria, Fanconi syndrome, Hereditary defects in metabolism of other reducing substances, ↑ ICP, nephrotoxic chemicals

Urinary Leukocyte esterase Screen to detect leukocytes in urine (dipstick method) Presence indicates UTI 90% accurate

Urinary Ketones End products of fatty acid catabolism Examples: β-hydroxybutyric acid, acetoacetic acid, acetone Associated with poorly controlled diabetes Used to evaluate ketoacidosis associated w/ alcoholism, fasting, starvation, high- protein diets, isopropanol ingestion

Urinary Nitrites Screen for UTI (dipstick method) Test based on chemical rxn by bacterial reductase (reduces nitrate to nitrite) 50% accurate Enhances leukocyte esterase sensitivity

Urinary Casts Hyaline – conglomerations of protein; indicative of proteinuria; few = normal especially after exercise Cellular – conglomerations of degenerated cells –Granular – glomerular disease –Fatty – nephrotic syndrome –Waxy – chronic renal disease –Epithelial cells & casts (renal tubular casts) –WBCs & casts – acute pyelonephritis –RBCs & casts – glomerular diseases

Cerebral Spinal Fluid (CSF) Analysis Collected via lumbar puncture (LP) Useful for the diagnosis of 1° or metastatic brain/spinal cord neoplasm, cerebral hemorrhage, meningitis, encephalitis, degenerative brain disease, autoimmune diseases w/ CNS involvement, neurosyphilis, demyelinating diseases

CSF analysis Normal Values Opening pressure: <20 cm H 2 O Color: clear & colorless Blood: none RBCs: 0 WBCs: 0 – 5 cells/μL Neutrophils: 0 – 6% Lymphocytes: 40 – 80% Monocytes: 15 – 45%

CSF analysis Normal Values cont. Protein: 15 – 45 mg/dL Glucose: 50 – 75 mg/dL or 60 – 70% of blood glucose level

CSF WBC count Pleocytosis – turbidity of CSF due to increased #s of cells

CSF PMNs Causes of ↑ PMNs: bacterial meningitis, tubercular meningitis, cerebral abscess, subarachnoid bleeding, tumor

CSF Lymphs Causes of ↑ lymphs/plasma cells: viral, tubercular, fungal or syphilitic meningitis; multiple sclerosis (MS), Guillain-Barré syndrome

CSF Monos Causes of ↑ monos: tubercular or fungal meningitis, hemorrhage, brain infarction

CSF Profile RBCs/mm 3 WBCs/m m 3 Glucose (mg/dL) Protein (mg/dL) Opening pressure (cm H 2 O) Appearan ce γ-globulin (% protein) Bacterial meningitis ↑ (> 1,000 PNMs) ↓ (< 45 mg/dL) ↑ (> 250 mg/dL) ↑Cloudy Viral meningitis ↑ (lymphs/m onos) Aseptic meningitis ↑ SAH↑ ↑↑ Guillain- Barré syndrome ↑ MSNormal in 2/3 pts; > 15 in < 5% of pts ↑ Pseudotu mor cerebri ↑ ↑ ↑

References Pagana, K.D. & Pagna, T.J. (2006). Mosby’s Manual of Diagnostic and Laboratory Tests. St. Louis: Mosby Elsevier. 27 th edition (2000). Stedman’s Medical Dictionary. Baltimore: Lippincott Williams & Wilkins. UpToDate. Retrieved July 26, 2009, from Urinalysis. Retrieved July 17, 2009, from URINE.html URINE.html Vital Signs. Retrieved July 17, 2009, from ntrauma/vital.cfm

Additional Resources Corbett, J.V. (2008). Laboratory Tests and Diagnostic Procedures with Nursing Diagnoses 7 th Edition. Upper Saddle River: Prentice Hall. Fischbach, F.T. & Dunning, M.B. (2008). A Manual of Laboratory & Diagnostic Tests 8 th Edition. Philadelphia: Lippincott Williams & Wilkins. Jacobs, D.S., De Mott, W.R. & Oxley, D.K. (2001). Jacobs & DeMott Laboratory Test Handbook with Key Word Index 5 th Edition. Hudson: Lexi Comp, Inc. Wu, A. (2006). Tietz Clinical Guide to Laboratory Tests 4 th Edition. St. Louis: Saunders Elsevier. Young, R.H. & Hicks, J. (2002). Directory of Rare Analyses St. Louis: AACC Press.

Special Thanks Dr. Amira F. Gohara, M.D. Dr. Carol Bennett-Clarke, Ph.D. Dr. Constance Shriner, Ph.D. Cynthia R. O’Connell, BSMT (ASCP)