Blood Collection Equipment: Selection, Use, and Quality Considerations

Introduction to Blood Collection Equipment

Proper blood collection is fundamental to accurate laboratory testing. Understanding equipment selection, proper technique, and quality requirements ensures specimen integrity and patient safety in phlebotomy practice.

Collection System Types

Evacuated Tube Systems (ETS)

The most common blood collection method using pre-evacuated tubes:

• Standardized vacuum for consistent fill volumes
• Closed system reduces contamination risk
• Multiple tubes collected with single venipuncture
• Available in various sizes and additive types

Syringe Collection

Used when veins are fragile or difficult to access:

• Allows controlled aspiration
• Requires transfer to appropriate tubes
• Higher contamination risk during transfer
• May cause hemolysis if transferred too forcefully

Winged Infusion Sets (Butterfly)

Provides better control for difficult draws:

• Smaller gauge needles available
• Flexible tubing allows hand movement
• Ideal for hand veins and pediatric patients
• Higher cost than straight needles

Tube Selection and Order of Draw

Tube Color Coding

Color	Additive	Common Tests
Light Blue	Sodium Citrate	Coagulation (PT, PTT)
Red	None (Clot Activator)	Chemistry, Serology
Gold/SST	Clot Activator + Gel	Chemistry panels
Green	Heparin	Chemistry, Blood Gas
Lavender	EDTA	Hematology (CBC)
Gray	Sodium Fluoride	Glucose, Blood Alcohol
Yellow	ACD or SPS	Blood Bank, Cultures

Standard Order of Draw

Following proper order prevents additive carryover:

1. Blood cultures (sterile)
2. Light blue (citrate)
3. Red or gold (serum)
4. Green (heparin)
5. Lavender (EDTA)
6. Gray (oxalate/fluoride)

Needle Selection

Gauge Considerations

• 21 gauge: Standard for most adults
• 22 gauge: Smaller veins, pediatric patients
• 23 gauge: Very small or fragile veins
• Larger gauges (18-20): Blood donations only

Length Selection

• 1 inch: Standard venipuncture
• 3/4 inch: Pediatric, butterfly needles
• 1.5 inch: Larger patients, deep veins

Safety-Engineered Devices

OSHA Requirements

The Needlestick Safety and Prevention Act requires employers to use safety-engineered sharps devices where available and appropriate.

Safety Features

• Retractable needles
• Shielding mechanisms
• Self-blunting needles
• Needleless transfer devices

Tourniquet Use

Types Available

• Latex rubber strips (traditional)
• Non-latex alternatives
• Velcro-closure tourniquets
• Single-use disposable options

Proper Application

• Apply 3-4 inches above collection site
• Snug but not too tight
• Remove within 1 minute to prevent hemoconcentration
• Release before removing needle

Site Preparation

Antiseptic Options

• 70% Isopropyl alcohol: Standard venipuncture
• Iodine: Blood cultures, sterile specimens
• Chlorhexidine: Alternative for iodine sensitivity

Preparation Technique

1. Apply antiseptic to collection site
2. Use circular motion from center outward
3. Allow to air dry completely (30-60 seconds)
4. Do not palpate site after cleaning
5. Re-clean if site touched

Quality Considerations

Equipment Storage

• Store tubes at recommended temperature
• Check expiration dates before use
• Protect from light and extreme temperatures
• Rotate stock (first in, first out)

Specimen Quality Indicators

• Hemolysis: Caused by traumatic draw, small gauge, or vigorous mixing
• Clotting: Insufficient mixing with anticoagulant
• Under/overfilled: Incorrect additive ratio
• Lipemia: Patient not fasting when required

Capillary Collection

Equipment

• Lancets (various depths)
• Microcollection containers
• Capillary tubes
• Warming devices

Site Selection

• Adults: Fingertips (middle or ring finger)
• Infants: Heel (medial or lateral plantar surface)
• Avoid edematous, cold, or cyanotic areas

Blood Culture Collection

Special Requirements

• Strict aseptic technique
• Thorough skin antisepsis
• Adequate volume (8-10 mL per bottle for adults)
• Proper bottle inoculation order
• Collection from separate sites preferred

Contamination Prevention

• Clean bottle tops before inoculation
• Do not change needles between bottles
• Inoculate bottles directly from blood draw
• Label with collection time and site

Pediatric Considerations

Equipment Selection

• Smaller tubes with lower vacuum
• Smaller gauge butterfly needles
• Microcollection devices
• Age-appropriate restraint methods

Volume Limits

Maximum safe blood volume is calculated based on patient weight. Generally, no more than 3% of blood volume should be collected in a 24-hour period.

Documentation and Labeling

Required Label Information

• Patient name and identifier
• Date and time of collection
• Collector identification
• Specimen type

Chain of Custody

Required for legal specimens (drug testing, forensic):

• Tamper-evident containers
• Witnessed collection
• Complete documentation of handling

Conclusion

Proper blood collection equipment selection and use directly impacts specimen quality and patient safety. Understanding the various tools available and their appropriate applications ensures reliable laboratory results and minimizes patient discomfort.