Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MELS301 > Week 1 > Flashcards

Week 1 Flashcards

1
Q

4 qualities in a good venepuncture vein

A
  1. Well anchored to the skin
  2. Shows elasticity
  3. Large enough for good blood flow
  4. Easily visible
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Pre analytical factors

A

Test ordering system, patient ID matching sample, patient preparation, specimen transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Analytical factors

A

Calibration, reagents, QC, equipment maintenance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Post analytical factors

A

Result reporting, turn around time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Non analytical factors

A

Staff training, lab policies, health and safety

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Best vein for venepuncture and why

A

Median cubital vein as it is large and well anchored, less painful and likely to bruise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Second best venepuncture vein and why

A

Cephalic vein
May be more painful, not as well anchored but large

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

3rd best venepuncture vein

A

Easy to palpate but more painful and near brachial artery/nerve which could cause pain and you don’t want artery blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Secondary venepuncture sites

A

Hands and feet is the last resort

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are some inappropriate venepuncture sites

A

Edematous/lympodema sites
Bruised and scarred areas
Arms with grafts/fistula
Inner wrist
Diabetic feet/ anyone with peripheral vascular disease
Arm with IV in, use the other arm or hand
Thrombosed veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Types of needles

A

Flashback- to see if you’re in a vein
Butterfly - good for training, less pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Hand washing precaution

A

Assume all substances from the body are dangerous
Wash hands before and after touching patients/doing a procedure and after touching surroundings near a patient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Procedure before sticking the needle in

A

Wash hands
Greet patient and check ID
Position patient
Consider the vein using a torniquet
Alcohol wipe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Order of draw saying

A

Stop light red, green light go

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Order of draw colour order

A

Light blue
Red
Gold
Green
Light green
Lavender
Grey

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Light blue tube

A

First in order of draw as it uses a weak anticoagulant reversible
Na citrate
Looking at coagulation and platelets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Red tube

A

Second in draw order
Plain tube
No anticoagulants as you want the blood to clot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Gold tube

A

SST
3rd in order
Serum, no anticoagulants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Light green

A

5th
PST plasma
Non coagulating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Green tube

A

4TH
LiHep
Non coagulating plasma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Lavender tube

A

6th
EDTA
Whole blood used for blood films and HbAc1, full blood counts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Grey tube

A

Last in order of draw
NaF or F oxalate
Plasma
For glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Pink tube

A

Just before grey
EDTA for blood banks only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Tourniquet uses

A

Make veins easier to feel and locate
10cm above vein
Stays on for 1 min at a time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What happens if tourniquet for longer than a min

A

Haemo concentration so increase in proteins/albumin/Ca
Water balance changes
Haemolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What do you clean the venepuncture surface/ features

A

70% alcohol
Circular motion, wait 30sec to dry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Underfilling tube leads to

A

Excessive additive
Not enough blood for testing
Need to recollect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Overfilling tubes results in /common with what type

A

Not enough additive in tube
Common with syringe draws

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

When do you remove the needle in regards to tourniquet

A

After the tourniquet is released

30
Q

What do you do after removing the needle

A

Dispose it first
Apply pressure second

31
Q

Should you bend arm after venepuncture

A

No
Do not wipe either

32
Q

What to do with tubes after needle is disposed of

A

Gently invert
Label patient info
Then give plaster

33
Q

How many times do you invert a citrate tube

A

3-4x

34
Q

How many times do you invert every tube but citrate

A

8-10x

35
Q

What is phlebotomy syncope

A

1% of procedures
Vasovagal response - BV dilate, heart rate slows down, BP drops so less blood reaches brain
Fainting after procedure

36
Q

What to do if patient feels faint

A

Stop procedure
Call for assistance
Remove needle and tourniquet
Apply pressure to wound
Head between knees if seated
Elevate legs if on back
111 if not breathing
Cold compress to back of neck
Stay with patient for 15-30 mins
No vehicle operation 30 mins after fainting

37
Q

What are influencing factors

A

Cause a true change in analyse quantity
Patient related not method

38
Q

What are interfering factors

A

Cause a false change in analyse quantity
Dependent on method more so

39
Q

What are some modifiable influencing factors

A

Fasting state
Exercise before coming in
Vein or artery blood
Posture
Tourniquet
Treatments

40
Q

What are some unmodifiable influencing factors

A

Sex, race, gender
Medications
Disease state
Pregnancy
Period
Mode of baby delivery
Altitude

41
Q

What are some endogenous interfering factors

A

Tourniquet left on too long = haemoconcentration
Lipaemia
Icterus
Paraproteins
Pathologies

42
Q

List exogenous interfering factors

A

Shaking tube
Wrong tube additive
Didn’t invert
In vitro haemolysis from tube temp
Drugs
Tracer dye
Canula additives
Tube additives
Clot in tube

43
Q

How to reduce influencing and interfering factors

A

Standardise methods

44
Q

Beer lambert law

A

For spectrophotometry

45
Q

Small particle scattering

A

Not all light is absorbed
Symmetrical scattering
Less than 5% of wavelength

46
Q

Large particle scattering

A

Due to constructive and destructive interferences
Forward scattering increases
Backwards scattering decreases so asymmetrical

47
Q

What is turbidimetry measuring and what type of particles is it better for

A

Decrease in transmitted light is measured
Better for larger particles and higher concentrations

48
Q

Detector placement in turbidity vs nephelometry

A

In turbidity the detector is in line with the source
In neph the detector is at a 90 angle to the source

49
Q

What is nephelometry measuring

A

Scattered light
Better for smaller particles at lower concentrations
More scattered =less absorbed

50
Q

What is haemolysis

A

Disruption in blood cell membrane causing lysis of RBC

51
Q

What is the most common preanalytical error in chem path tests

A

Haemolysis

52
Q

In vivid haemolysis occurs how/ what proteins does this effect

A

Due to pathology
Less serum haptoglobin
Increased urine Hb
Sample reflects patient so it’s fine

53
Q

In vitro haemolysis cause

A

Cells damaged via
Vein trauma
Needle size
Syringe collection too fast
IV lines
Shaking tubing
Temp
May need to redraw

54
Q

How does haemolysis cause spectrophotometric interference

A

Causes peaks at 415, 540, 570nm
False analyte conc

55
Q

Haemolysis causes interference by increasing what analyte conc

A

LDH
Pi
AST
K+
In plasma

56
Q

What does haemolysis do to sample dilution

A

Effects analytes with greater extracellular conc like albumin, Ana and bilirubin

57
Q

How does haemolysis affect assays with an example

A

It competes for binding sites, inhibit reactions
Free Hb may start binding

58
Q

When is lipaemia found the most

A

Lipid disorders
Acute pancreatitis
Drugs some
Post prandial samples
Had a fatty meal

59
Q

What type of fats contribute to lipaemia

A

Lipoproteins chylomicrons
VLDL

60
Q

How to reduce lipaemia in blood samples

A

Fasting before the sample is taken
Lipid clearing agents
High speed centrifugation so lipids go to the top

61
Q

How does lipaemia cause spectrophotometric interference

A

Absorption decreases between 300-700n
Light scattering interferes with turbidity and nephelometry

62
Q

What is the volume depletion in lipaemia

A

Lipid droplets take up volume in aspirated sample
Falsely decrease concentration of analyte of interest

63
Q

Random problems with lipaemia

A

Abnormal peaks in electrophoresis
Masking of binding sites
Partitioning of sample hard for automatic analyser

64
Q

What is icterus

A

High bilirubin levels in plasma/serum

65
Q

When is icterus samples seen

A

Liver disease
Cancer
Neonates

66
Q

How does icterus interfere

A

Spec interference at 400-540nm
Chemical interference with hydrogen peroxide for cholesterol/glucose/triglyceride

67
Q

What does automated serum indices measure

A

Haemolysis
Lipaemia
Icterus

68
Q

How does automated serum indices work

A

Sample blanked at absorbance maxima of Hb/lipids/bilirubin and interference is graded and unsuitable samples are flagged

69
Q

What is bichromatic analysis

A

Measures two wavelengths
Measures absorbance at points where no change in absorbance occurs and is used as a reference point

70
Q

Example of bichromatic analysis with equations

A

Want to measure chromogen but bilirubin will interfere
Primary absorbance - bilirubin absorbance = absorbance from chromogen
Abs at 2nd - 1st = abs from interference

MELS301 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions