[2] skin puncture Flashcards
rationale
this is the first step in most laboratory analysis
specimen collection
rationale
____ and ____ can be measured by the proper specimen collection and handling.
Accuracy and precision
Test results are therefore said to be as good as ____
this quality depends on? (3)
sample collection and handling
This quality depends on how a specimen was collected, transported, and processed.
The phlebotomist as a laboratory ambassador (3)
- Frequently the only laboratory staff member that a patient sees
- Represents the professional image of the laboratory
- Expected to deliver unexcelled customer satisfaction
characteristics of blood (6)
why do males and females have different blood volumes?
- It is in fluid form in vivo due to the naturally circulating anticoagulants, but in vitro it coagulates within 5-10 minutes.
- Red in color due to hemoglobin
- A ph average of 7.35-7.45
- Thick and viscous (3.5 – 4.5 times thicker than water)
- For adult males, they have approx. 5-6 liters of blood
- For adult females, have 4 to 5 liters of blood
- Males have bigger builds than females
- Females menstruate
composition (of blood?) (3)
what are the contents of each?
why does serum not have what plasma has </3
-
Liquid Portion (centrifugation)
* Plasma – liquid portion of the unclotted blood with the protein fibrinogen
* Serum – liquid portion of the clotted blood without the fibrinogen. -
Solid portion
* Red blood cells
* White blood cells
* Platelets -
Gaseous portion
* Involves an exchange between oxygen and carbon dioxide
Serum has no fibrinogen cus nagamit sya sa clot
preparation of blood sample
3 specimens that can be used
- whole blood
- serum
- plasma
Whole blood specimen (3)
- It must be analyzed within limited time
- Over time, cells will lyse in whole blood which will change the concentration of some analytes as potassium, phosphate and lactate dehydrogenase. (3)
- Some cellular metabolic processes will continue which will alter analytes concentration like glucose and lactate.
- room temp
- no centrifugation
- cells change morphology after 2 hrs
difference between serum and plasma
- Serum is the same as plasma except it doesn’t contain clotting factors (as fibrin).
- Plasma contains all clotting factors.
- Serum and plasma all have the same contents of electrolytes, enzymes proteins, hormones except clotting factors
- Serum is mainly use in chemistry lab & serology
Coagulation Reaction
Clotting factors + calcium → thrombin
Fibrinogen + thrombin → fibrin strands
if u lack proteins, u can still bleed as long as u have clotting factors
FIRST STEP
Patient Identification
Types of Patients for Patient Identification (5)
- Conscious In-patients
- Sleeping patients
- Unconscious patients/Mentally incompentent patients
- Infants and Children
- Outpatient patient
patient identification procedures
Conscious In-patients
verbally ask their full names, verify it using the identification bracelet which includes first and last name, hospital number/unit number, room/bed and physician’s name.
patient identification procedures
Sleeping patients
they must be awakened before blood collection. Identified same as conscious patients.
patient identification procedures
Unconscious patients / Mentally incompetent patients
identified by asking the attending nurse or relative; ID bracelet
patient identification procedures
Infants and Children
nurse, relative, or guardian may identify the patient or by ID bracelet
patient identification procedures
Outpatient patient
verbally ask their full name, DOB and countercheck with driver’s license or id with photo. If the patient has id card or bracelet, same manner as with hospitalized patients.
3 types of patients (?)
- Pediatric patients
- Adolescent patients
- Geriatric patients
pediatric patients
- Be gentle and treat them with compassion, empathy, and kindness.
- Attempt to interact with the pediatric patient
- Acknowledge the parent and the child. Be friendly, courteous, and responsive. Allow enough time for the procedure
adolescent patients
- When obtaining a blood specimen from an adolescent, it is important to be relaxed and perceptive about any anxiety that he or she may have.
- General interaction techniques include allowing enough time for the procedure, establishing eye contact, and allowing the patient to maintain a sense of control.
geriatric patients
- Treat geriatric patients with dignity and respect. Do not demean the patient. It is best to address the patient with a more formal title such as Mrs., Ms., or Mr. rather than by his or her first name.
- Senior patients may enjoy a short conversation. Keep a flexible agenda so that enough time is allowed for the patient.
-
Speak slowly and allow enough time for questions. The elderly have the right of informed consent. Too many times this fact is lost in dealing with any patient, but it seems more prevalent in dealing with
aging patients.
- Voice must still be modulated
- Veins sometimes move or collapse
○ Pull skin to stabilize the vein
Skin Puncture/Capillary Puncture
(5)
Does it need a specific orientation? Why?
- A fingerstick to obtain blood for routine laboratory analysis and usually preferred for children.
- Also known as Dermal Puncture
- Length of the lancet: 1.75mm
- The depth of the incision should be < 2.0mm for children and < 2.5mm for adults.
- The cut should be oriented across the fingerprints to generate a large drop of blood using single deliberate motion.
- across fingerprints / perpendicular para mo ball ang blood + not messy
what if patient has 3rd degree burns?
- Don’t disinfect (hapdos kaau)
- Diretso nag veni
Preferred Sites
(4)
- Lateral plantar heel surface – newborns and infants
- Palmar surface of the non dominant fingers (3rd and 4th fingers) – most common (if patient has dengue, u can use other fingers and toes)
- Plantar surface of the big toe (not good for adults cus its calloused)
- Earlobes – least used site (least painful + gamay ray blood)
- squeeze baby’s foot when puncturing
- careful taking sa heel cus its near an artery
Sites to avoid
(4)
- Inflamed and pallor areas
- Cold and cyanotic areas
- Congested and edematous (pitting) areas
- Scarred and heavily calloused areas
- also avoid dry/peeling skin
- if calloused ang fingers, u can find a soft spot
Advantages (3)
- It is accessible to the operator
- Easy to manipulate
- Ideal for peripheral blood smears. (if sa lab, purple tube; bedside blood smearing - skin puncture)
Disadvantages
- Less amount of blood can be obtained (esp sa ears n fingers if dli bleeder si patient)
- Additional and repeated test cannot be done
- Blood obtained has tendencies to hemolyze easily. (alcohol can hemolyze sample; dry b4 puncture)
Capillary puncture materials
(6)
- Lancets
- Alcohol, Gauze, Bandages
- Microcollection containers
- Microhematocrit tubes
- Warming devices
- Sealants
Lancets
Lancets are sterile, disposable, sharp instruments used for capillary puncture. Their blades or points must permanently retract to prevent sharp injuries.
Alcohol, Gauze, Bandages
(3)
what motion ang pag disinfect? and why do we need to disinfect?
- CLSI recommends using 70% isopropyl alcohol (basta >40%) to clean surface of the skin before puncturing with a lancet or other sharp device.
- Gauze or cotton balls are used to wipe away the first blood drop to eliminate alcohol residue and excess tissue fluid.
- Bandages are used to cover the site after collection.
- concentric motion (inwart to outward); pwede pd 1 swipe
- removes debris and microorganisms
- bandages are only used when bleeding stops
Microcollection containers
(3)
volume?
- Also known as microtubes / microtainers
- Special small plastic tubes used to collect tiny amounts of blood obtained from capillary punctures
- Often referred to as bullets because of their size and shape
- 250uL - 500uL or 1mL max
- not limited to skin puncture; can also be used if na short draw sa ETS
Microhematocrit tubes
(5)
- Disposable, narrow-bore plastic or plastic-clad glass capillary tubes that fill by capillary action and typically hold 50-75 uL of blood.
- Used primarily for manual hematocrit / packed cell volume (PCV) determinations
- Coated with ammonium heparin or plain
- Heparin tubes have red or green band on one end
- Nonadditive tubes have blue band
- green and red get directly from site
- blue gets from purple top tube
Warming Devices
(2)
what if wala?
- Warming the sites increases blood flow up to 7 times and is especially important when performing heel sticks.
- Water temperature must not exceed 42ºC or it could scald the patient.
- massage
- cloth e hulom sa warm water then wrap around site
- glass bottle w/ warm inside, e touch sa patient
Sealants
(3)
- Sealants are claylike substances used to seal one end of microhematocrit tubes.
- Followed by Paraffin Wax
- The clay plug should be 4-6mm long
procedure for skin puncture
(9)
- Identify the patient properly
- Choose an appropriate site for collection
- Clean the site with 70% alcohol
- Hold finger between your index finger and thumb
- Puncture the finger using a quick, smooth motion
- Wipe away the first drop of blood
- Collect blood sample
- Apply pressure to puncture site
- Label specimen in sight of patient
- thumb - naay pulse
- pinky - duol sa bone tip
- index - callous
- ask which one is dominant hand
- ask if allergic to latex/nitrile etc.
- fill capillary tube 2/3 - 3/4 full; 8 inversions
indications for capillary puncture
(5)
- Can be done if small amount of blood is required. (hematocrit)
- There are no accessible veins
- Available veins are fragile or must be saved for other procedures such as chemotherapy
- Blood is to be obtained for POCT procedures such as glucose monitoring
- Capillary blood is the preferred specimen for some tests such as newborn screening
specimen quality
(5)
- Capillary blood obtained through skin puncture transferred to an anticoagulated capillary tube (HEPARIN) – with RED BAND
- EDTA-anticoagulated blood transferred to a non-anticoagulated capillary tube – with BLUE BAND
- NOTE: CAPILLARY TUBES MUST BE 2/3 TO ¾ FULL
- Avoid air bubbles and spaces
- Sealed first with a clay sealant then paraffin
proper labelling
(5)
Label the specimen properly with:
* patient’s full name
* age
* date of birth
* time and date of collection
* initials of the phlebotomist
Order of Draw (microtainer)
(5)
why is order of draw important?
- Blood Gases (CBGs)
- Slides & Smears
- EDTA tubes
- Other additive microtainer
- Serum microtainer
- to avoid contamination (affects test results)
- microtainers have a different order of draw from the big tubes (ETS)
