Pathology and Pediatrics. Flashcards
What are the types of laboratory samples?
1: Blood samples
A.Venous, easiest and phlebotomy to acquire venous sample commonly veins of antecubital fossa.
B. Arterial, measure arterial blood gases O2, CO2 and pH.
C. Capillary, pediatric and bed side tests commonly in fingertips and heel.
2. Urine, stool, sputum, nasal discharge.
3. Ascitic, synovial, pleural and csf.
4. Seminal and prostatic fluids.
5. Brochoalveolar lavage, tissues for culture.
6. Swabs for nasopharynx, oral cavity, vagina and wounds.
7. Any unknown collection of fluid and abscess.
8. Bone marrow.
What are the general rules before sampling ?
1) The appropriate container is ready
2) Proper labelling of the sample container with full patient data (full name, hospital number, ward, β¦.), type of sample (blood, body fluid,β¦), and the required tests. In clinical laboratories, where information system is applied, barcoded label with the previous date in addition to unique sample number is used for labelling the samples.
3) The clinician/nurses must ensure proper patient preparation prerequisites before sampling (e.g., fasting patient, 2 hours after drug therapy in case of therapeutic drug monitoring, etc.). Clinical pathologists provide the clinician with these data.
4) The appropriate transport container is available
Causes of errors related to sample collection procedure?
Pre collection:
1.Failure to adhere to proper patient preparation according to the requested test
2.Failure to adhere to proper timing in sampling
3.Vigorous activity before sample collection affect results of some tests
During collection:
1. Prolonged tourniquet pressure results in haemo-concentration.
2.Excessive negative pressure when drawing blood into syringe results in hemolysis.
3.Using incorrect type of tube for blood collection
Handling of sample:
1. Insufficient or excess anticoagulant
2. Inadequate mixing of blood with anticoagulant.
3. Error in patient and/or specimen identification results in mix up of results
4. Inadequate specimen storage conditions affect the result of some tests
5. Delay in transport to laboratory affects the result of some tests
Why might the lab reject a sample?
ο· The request does not contain the appropriate data.
ο· The sample tube is inappropriate for the requested tests.
ο· The Sample is not appropriately identified i.e., no name on tube.
ο· The sample shows a visible clot in a supposedly anticoagulated sample.
What is a test panel
It is a group of tests that are routinely ordered to determine the status of a major body organs
Usually on a blood sample
Example of test panels
- Liver Panel β used to screen, detect, evaluate, and
monitor acute and chronic liver inflammation, liver disease and/or damage. It includes Total ,direct bilirubin, total protein, albumin, and liver enzymes [AST, ALT, and ALP]. - Renal Panel β contains tests such as creatinine, urea,
uric acid , estimated glomerular filtration rate (eGFR) to evaluate kidney function. - Thyroid Function Panel β used to evaluate thyroid gland function, diagnose thyroid
disorders, and follow up of treatment. It includes TSH, FreeT4, Free T3, T4, T3.
Criteria of accurate lab report?
ο· Patient identifiers (full name, age, sex, hospital number).
ο· Requester name
ο· Date and time of analysis.
ο· Test name, result, measuring unite, and reference interval.
ο· Result interpretation (where required and appropriate).
ο· Name of Clinical pathologist who released the report and date of release.
What is reference range and importance?
Its a statistically derived numerical range obtained by testing a sample from individuals assumed to be healthy.
This range represent the expected values in 95% of healthy population. This means that an abnormal result does not always indicate the presence of pathological process, nor a normal result indicates its absence. However, the more abnormal a result, that is, the greater its difference from the limits of the RI, the greater is the probability that it is related to a pathological process.
What is a critical value and its importance?
Value that is so far out of range as to represent a pathophysiological state that is life threatening and requires immediate appropriate
intervention.
1- White blood cell count (WBCs) <2x109/L & >30 x109/L.
2-Platelets <20 x109/L & >1000x109/L.
3- Hemoglobin <5 g/dl & >20 g/dl
4- Bilirubin (newborn) >15 mg/dl.
5- Sodium < 120 mmol/L & Λ150mmol/L.
What is a delta check
Delta check is a process to detect discrepancies in patient test results (that is not related to the patient clinical condition) prior to reporting by comparing current patient values to previous ones.
Onset of condition types
Sudden (Secs to mins)
Acute (Hours to few days)
Gradual (Within 1-2 weeks)
Chronic (Within weeks and months)
What is a good negative history is taken to?
-Rule in or rule out involvement of a system
-Identify the nature and etiology of the disease pattern
-Assess the severity and complications
Past history taken?
A. Perinatal
- Antenatal period (Illness, infection, iatrogenic and irradiation)
- Birth (Gestational age, birth weight, delivery, complications, place and mode of birth
-Neonatal (Illness, jaundice or any discoloration and admission to NICU.
B. Past history of:
-Medical illnesses, allergies and current medications.
-Major surgical illness (Operations/dates)
-Trauma fractures and lacerations
-Previous hospital admission (Dates/diagnosis)
C. Immunization (Specific and up to date)
D. Developmental history
E. Diabetic history
-Type of food?
- Satisfied after breast feeding or not
-intake and conc of artificial feed
-Frequency of feeding
-Special dietary requirements ?
Cardiac symptoms in infants
Difficulty of breathing
Recurrent lower respiratory tract infection
Cyanosis on crying
Collapse due to obstructed blood supply.
Failure to thrive.
Dysmorphic feature
Cardiac symptoms in older children
Difficulty of breathing
Palpitations Cyanosis
Squatting position
Chest pain
Syncope (Fainting or passing out)
cyanosis