ordering and interpreting laboratory values resident orientation
TRANSCRIPT
Ordering and Interpreting Laboratory Values
Resident Orientation
Outline
• Lab Structure• Available Tests at NMH• Ordering tests at NMH
– Collection– Ordering– Results – Cost
• Critical Values
Laboratory Structure
• Inpatient Hospital Lab
• Transfusion Services
• Outpatient Poly Clinic Laboratory
• Blood Donor Center
Laboratory Hours
• Normal Working Hours– Saturday – Wednesday:
0800 – 1500– Thursday: 0800 – 1200
• Duty Hours– Saturday – Wednesday:
1500 – 0800– Thursday: 1200 – 0800– Friday 0800 – 0800
Laboratory Contact Information• Inpatient Hospital
– Biochemistry 261-6683– Hematology 261-6693– Laboratory Chief 261-3224
• Blood Bank – 261-6682
• Outpatient Poly Clinic– Bacteriology 261-3187– Biochemistry 261-6659– Lab Director 261-3170
• Blood Donor Center– 261-6682
Available Tests at NMH
• Chem 7• Complete Blood Count
(CBC)• Urinalysis (UA)• Cultures
– Blood– Urine– Wound
Available Tests at NMH
• Malaria– Rapid Test– Smear
• Rapid TB• Serology
– H. pylori– Rheumatoid Factor– Hepatitis B and C– Syphilis– Febrile Antigen
Available Tests at NMH
• iSTAT– PT– Troponin I– Arterial Blood Gas
• Cholesterol and Triglycerides
• Blood Bank– Whole Blood– ABO testing– Rh testing
Indications for Ordering a CBC
• Concern for infection
• Concern for anemia
• Bleeding– Platelets
• To investigate hematological cancer– Leukemia
Indications for Ordering a Chemistry Panel
• Evaluate Electrolytes– Sodium– Potassium– Chloride– Calcium
• Evaluate Renal Function– BUN– Creatinine
• Diagnosis of Diabetes– Glucose
Indications for Ordering a Urinalysis
• Concern for a Urinary Tract Infection– White Blood Cells
• Concern for Diabetes– Glucose
• Evaluation of Renal Function– Albumin– RBCs
• Evaluation of Stone Disease– Crystals– RBCs
Specimen Collection Procedure
• Check patient’s identification
• Label specimen with patient’s name
• Transport specimen with order form
• Routine laboratory results are available daily after 1 pm
Collection• Red Top Tube
– Chem 7– Serology– Cross-match
• Blue Top Tube– Coagulation Studies
• Lavender Top Tube– CBC– Cross-match
Specimen Rejection
• Mismatched specimen requisition
• Improperly collected specimen
• Unlabeled specimen• Specimens without
requisitions• Contaminated specimen
or requisition
Test Priorities
• Tests will be run based on priority.
• Must specify priority when ordering test– Routine: 24 hours
– ASAP: 4 hours
– STAT: 1 hour
Priority اولیت زمان Expected TAT حقشده توقوع
ROUTINE24 روتین hours 24 ساعت
ASAP ممکن زودتر هرچه باشد
4 hours4 ساعت
STAT1 عاجل hour ساعت یک
Laboratory Costs• Chemistry
– 1000 Afghani
• Complete Blood Count– 120 Afghani
• Culture– 320 Afghani
• Cholesterol Panel– 550 Afghani
• Urinalysis– 6 Afghani
• Order only what you need, DO NOT WASTE MONEY
Results: Chemistry
• Chemistry Results will be prepared on a lab result paper and delivered to the ordering doctor
Results: CBC
• CBC results will be reported on this laboratory document and given to the physician
Results: Bacterial Sensitivities• After an organism grows
in a culture, the laboratory will automatically check the effectiveness of antibiotics on the bacteria
Results: Serology
• Serologic Tests will be reported on this laboratory sheet and given to the ordering doctor
Interpreting a Chemistry Panel• Sodium
– Normal: 136-145 mmol/l– Hypernatremia (> 145)
• Dehydration
– Hyponatremia (<136)• SIADH• Heart Failure• Medications
• Potassium– Normal: 3.5-5.2 mmol/l– Hyperkalemia (> 5.2)
• Renal Failure• Hyperaldosteronism• Medications
– Hypokalemia (< 3.5)• Vomiting / Diarrhea• Medications
Interpreting a Chemistry Panel• BUN
– Normal 15-50 mg/dl– > 50
• Renal Failure• Dehydration
– < 15• Malnutrition• Chronic Inflammation Syndromes
• Creatinine– Normal: 0.5-1.0 mg/dl– > 1.0
• Renal Failure• Dehydration
– < 0.5• Malnutrition• Decreased muscle mass
Interpreting a CBC• White Blood Cell
– Normal: 4000 – 10,000 cmm– < 4000
• Medications• Hematological Cancer
– > 10,000• Infection• Hematological cancer
• Hemoglobin– Normal 11.5-18.0 g/dl– > 18.0
• Hemochromatosis• Polycythemia Vera
– < 11.5• Anemia: disorder in production,
increased destruction, or bleeding
Interpreting a CBC
• Hematocrit (HCT)– Normal: 39-49%– > 49%– < 39%
• Platelets– Normal: 150,000-400,000
cmm– > 400,000
• Normal response to illness or inflammation
– < 150,000• Burns• Bone Marrow Disorders
Critical Values
• Lab results that are life threatening
• The laboratory Department Head will be notified
• Ordering physician will be notified
• As a resident, you should notify your instructor or staff physician
Critical Values: HematologyHEMATOLOGY
الوژی ت هم
TEST
آزمايش
VALUE LESS THAN
از كمتر مقدار
VALUE MORE THAN
از بیشتر مقدار
Prothrombin Time
خون ) ( علقه زمان تایم پروترومبیتN/A نیست دریافت seconds 30 قابل
WBC Count
خون سفيد حجرات تعداد
2,000/cumm 25,000/cumm
Hemoglobin
موگلوبينیه
7.0 g/dl 20.0 g/dl
Hematocrit
هماتوكريت
21.0% 50.0%
Platelet Count
دمویه صفحیات تعداد
50,000/cumm 1,000,000/cumm
Blood smear
خون سمير
Presence of immature WBC’s, immature RBC’s or malaria parasites.
ویا RBC’sنارس، WBC’s موجوديت نارسمالريا های پرازيت
Critical Values: ChemistryCHEMISTRYبیوشیمی
TEST
ازمايش
VALUE LESS THAN
از كمتر مقدار
VALUE MORE THAN
از بیشتر مقدار
Chloride, serum or plasma
پالزما یا كلورايد،سيروم
80 mmol/l 110 mmol/l
Creatinine, serum or plasma
پالزما یا سيروم كرياتينين،
N/A 5.0 mg/dl
Sodium, serum or plasma
پالزما یا سيروم ، سوديم
125 mmol/l 150 mmol/l
Critical Values: Chemistry ContinuedCHEMISTRYبیوشیمی
TEST
ازمايش
VALUE LESS THAN
از كمتر مقدار
VALUE MORE THAN
از بیشتر مقدار
Potassium, serum or plasma
یاپالزما پوتاشيم،سيروم
2.8 mmol/l 6.0 mmol/l
Glucose, serum or plasma
پالزما یا گلوكوز،سيروم
50 mg/dl 350 mg/dl
Ionized calcium, plasma
پالزما شده، ايونايز كلسيم
3.0 mg/dl 6.4 mg/dl
Urea nitrogen, serum or plasma
يوريانايتروجن،سيروم یاپالزما
N/A 80 mg/dl
Critical Values: UrinalysisURINALYSIS
ادرار معاينات
TEST
ازمايشVALUE LESS THAN
از كمتر مقدارVALUE MORE
THAN
از بیشتر مقدار
Glucose
گلوكوز
N/A >1000 mg/dl
Microscopic
مايكروسكوپيك N/APresence of pathological crystals )urate, cysteine, leucine, or tyrosine(
هاي كريستال موجوديتيورات،سيستين) ،پتالوژيك
تايروسين و (ليوسين
Ketones, urine/serum
/ سیروم ،ادرار ها كيتون
N/A نیست دریافت زیاد)mg/dl )Large 80< قابل
Critical Values: Arterial Blood GasARTERIAL BLOOD GASES
شيرياني خون گازهاي
TEST
آزمايشVALUE LESS THAN
از كمتر مقدارVALUE MORE THAN
از مقداربیشتر
pH, arterial, capillary
، شعریه عروق ، pH شيرياني
7.20 7.60
pCO2, arterial, capillary
اکساید،شریانی دای فشارکاربنوی شعریه ،
20 mm/Hg 70 mm/Hg
pO2, arterial
اکسیجن فشار شيرياني
40 mm/Hg N/A نیست دریافت قابل
Critical Values: Microbiology
MICROBIOLOGYمايكروبيولوژي
TEST آزمايش
VALUE LESS THANاز كمتر مقدار
VALUE MORE THANاز بیشتر مقدار
Blood Cultures
خون كلچرهای
N/A نیست دریافت Positive قابل
مثبت
Point of Care Testing
• Diagnostic testing at or near the site of patient care
• Available in– ICU– Internal medicine
• Available tests– Chemistry 8– Arterial Blood Gas– PT/INR
Conclusions
• The laboratory can provide valuable information to help diagnose and treat patients.
• Always take cost into consideration when ordering a test
• Learning to properly interpret lab results is essential for residents