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BSC – SEM 3 – UNIT 5 – INFECTION CONTROL & SAFETY

Specimen Collection (Review)

Specimen Collection.

Introduction

Specimen collection is a critical step in medical diagnostics and patient care. Proper collection, handling, and transport of specimens ensure accurate laboratory results, which guide diagnosis, treatment, and disease management. Errors in specimen collection can lead to misdiagnosis, treatment delays, and compromised patient safety.

Healthcare professionals must follow strict protocols to maintain specimen integrity, prevent contamination, and ensure patient safety.


1. General Principles of Specimen Collection

  • Ensure patient identification – Use at least two identifiers (name, hospital ID, or date of birth).
  • Select the correct specimen type – Different tests require blood, urine, stool, sputum, tissue, or other body fluids.
  • Follow aseptic techniques – Prevent contamination using sterile gloves, disinfectants, and clean collection tools.
  • Use appropriate containers – Specimens must be collected in labeled, sterile, and leak-proof containers.
  • Follow collection timing guidelines – Some tests require fasting, morning samples, or collection at specific intervals.
  • Ensure proper storage and transport – Maintain the required temperature (room temperature, refrigerated, or frozen).
  • Minimize patient discomfort – Use proper techniques and reassure the patient.
  • Document collection details – Include date, time, collector’s name, and special conditions.

2. Types of Specimen Collection

Specimens are collected from various body fluids, tissues, and secretions for diagnostic testing. The most common types include:

A. Blood Specimen Collection

Purpose:

  • Diagnose infections, anemia, clotting disorders, and chronic diseases.
  • Monitor blood glucose, cholesterol, and organ function.
  • Assess immune response and therapeutic drug levels.

Types of Blood Collection:

  1. Venipuncture (Venous Blood Collection)
    • Collected from a vein (e.g., antecubital vein).
    • Uses a vacutainer system, syringe, or butterfly needle.
    • Commonly used for CBC, blood culture, glucose tests.
  2. Capillary Blood Collection
    • Collected from fingertips (adults), heel (infants).
    • Used for blood glucose monitoring, newborn screening.
    • Requires a lancet and capillary tubes.
  3. Arterial Blood Collection
    • Collected from an artery (radial, brachial, femoral).
    • Used for arterial blood gas (ABG) analysis.
    • Requires heparinized syringes and immediate transport.

Precautions for Blood Collection:

  • Use proper antiseptic techniques (70% alcohol or iodine).
  • Avoid hemolysis by gentle handling.
  • Use the correct order of draw to prevent contamination.
  • Label tubes immediately after collection.

B. Urine Specimen Collection

Purpose:

  • Diagnose urinary tract infections (UTI), kidney disease, diabetes, drug use.
  • Assess hormone levels and metabolic disorders.

Types of Urine Collection:

  1. Random Urine Sample
    • Collected at any time of the day.
    • Used for routine urinalysis, pregnancy tests.
  2. Midstream Clean-Catch Urine Sample
    • Collected midstream after perineal cleaning.
    • Used for urine culture to detect bacterial infections.
  3. 24-Hour Urine Collection
    • All urine over 24 hours is collected in a single container.
    • Used to measure protein, creatinine clearance, electrolytes.
  4. Catheterized Urine Collection
    • Collected using a sterile catheter.
    • Used for patients unable to void normally.

Precautions for Urine Collection:

  • Use sterile containers for urine culture.
  • Refrigerate 24-hour urine samples to prevent bacterial growth.
  • Label containers properly with date, time, and patient information.

C. Stool Specimen Collection

Purpose:

  • Diagnose gastrointestinal infections, parasites, digestive disorders.
  • Detect occult (hidden) blood in stool.

Types of Stool Tests:

  1. Routine Stool Examination – For detecting parasites, bacteria, fungi.
  2. Occult Blood Test (FOBT) – Checks for hidden blood (indicative of GI bleeding).
  3. Fecal Fat Analysis – Used to diagnose malabsorption syndromes.

Precautions for Stool Collection:

  • Use clean, dry containers.
  • Avoid contamination with urine or toilet water.
  • Transport within 1-2 hours for microbiological tests.

D. Sputum Specimen Collection

Purpose:

  • Diagnose respiratory infections, tuberculosis (TB), pneumonia, lung cancer.

Types of Sputum Collection:

  1. Spontaneous Sputum Collection – Patient coughs into a sterile container.
  2. Induced Sputum Collection – Patient inhales a saline mist to induce sputum production.

Precautions for Sputum Collection:

  • Collect early morning samples before eating or drinking.
  • Avoid contaminating sputum with saliva.
  • Refrigerate if transport is delayed.

E. Swab Specimen Collection

Purpose:

  • Detect bacterial, viral, or fungal infections.
  • Identify throat, wound, or genital infections.

Types of Swab Collections:

  1. Throat Swab – Detects strep throat, diphtheria.
  2. Nasal Swab – Used for COVID-19, flu, MRSA screening.
  3. Wound Swab – Identifies infectious agents in wounds.
  4. Genital Swab – Detects STIs (chlamydia, gonorrhea, HPV).

Precautions for Swab Collection:

  • Use sterile swabs and avoid contamination.
  • Store viral specimens in transport medium.
  • Label correctly and transport immediately.

F. Cerebrospinal Fluid (CSF) Collection

Purpose:

  • Diagnose meningitis, encephalitis, brain infections.
  • Assess intracranial pressure.

Collection Method:

  • Collected via lumbar puncture (spinal tap).
  • Requires strict aseptic technique.

Precautions:

  • Handle CSF with care (risk of contamination).
  • Transport immediately at room temperature.

G. Tissue and Biopsy Specimens

Purpose:

  • Diagnose cancers, infections, autoimmune diseases.
  • Examine histopathological changes.

Types of Biopsy Collection:

  1. Needle Biopsy – Fine needle aspiration for tumors or cysts.
  2. Surgical Biopsy – Open biopsy for larger tissue samples.
  3. Endoscopic Biopsy – Collected via gastroscopy, colonoscopy.

Precautions:

  • Preserve samples in formalin (histopathology) or sterile saline (microbiology).
  • Avoid crushing delicate tissues.

3. Specimen Handling and Transport Guidelines

  • Ensure proper labeling – Include patient name, date, time, and test requested.
  • Use the correct transport medium for microbial cultures.
  • Maintain proper temperature:
    • Refrigerate urine, stool, and blood samples if transport is delayed.
    • Keep CSF, blood cultures, and respiratory samples at room temperature.
  • Follow biohazard protocols – Use leak-proof containers and transport bags.
  • Minimize delays in delivery – Transport specimens within the recommended time frame.

4. Common Errors in Specimen Collection and How to Avoid Them

ErrorCausePrevention
Improper labelingMissing patient detailsVerify identity before collection
Contaminated samplePoor aseptic techniqueUse sterile equipment
Hemolyzed blood sampleRough handling, incorrect needle sizeUse gentle handling, correct technique
Inadequate sample volumeInsufficient collectionFollow recommended guidelines
Delayed transportSpecimen left at room temperature too longTransport immediately

Principles of Specimen Collection

Introduction

Specimen collection is a critical process in medical diagnostics that ensures accurate laboratory results for disease diagnosis, monitoring, and treatment planning. The effectiveness of laboratory tests depends on proper specimen collection, handling, storage, and transportation. Adhering to strict principles minimizes contamination, errors, and misdiagnosis.

The World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) provide guidelines to ensure safe and effective specimen collection.


1. General Principles of Specimen Collection

To obtain reliable test results, the following principles must be followed:

A. Proper Patient Identification

  • Use at least two patient identifiers (e.g., full name, hospital ID, date of birth).
  • Verify patient identity before specimen collection.
  • Ensure accurate labeling of specimen containers.

B. Correct Specimen Type and Collection Method

  • Use the appropriate specimen for the test (e.g., blood, urine, sputum, stool, swab, biopsy).
  • Follow standard operating procedures (SOPs) for each type of specimen.
  • Ensure adequate volume for testing.

C. Aseptic Technique

  • Use sterile equipment and proper hand hygiene.
  • Prevent cross-contamination by maintaining a clean environment.
  • Avoid touching the inner part of the container or swab tips.

D. Proper Timing of Collection

  • Some tests require morning samples (e.g., fasting blood glucose, sputum for tuberculosis).
  • Timed collections are needed for certain tests (e.g., 24-hour urine collection).
  • Blood cultures should be collected before starting antibiotic therapy.

E. Use of Appropriate Collection Containers

  • Choose the correct container based on the test:
    • Blood culture bottles for bacterial infections.
    • Urine culture containers for UTI diagnosis.
    • Vacutainer tubes for hematology and biochemistry tests.
  • Ensure containers are sterile and properly sealed.

F. Maintaining Specimen Integrity

  • Prevent hemolysis in blood samples by handling tubes gently.
  • Use preservatives when necessary (e.g., boric acid for urine, formalin for tissue biopsy).
  • Ensure proper storage temperature (e.g., refrigerated, room temperature, frozen).

G. Safety and Infection Control

  • Follow standard precautions (gloves, masks, gowns).
  • Dispose of sharps and biohazard waste properly.
  • Ensure spill management in case of accidental leakage.

H. Proper Labeling and Documentation

  • Label specimen containers with:
    • Patient’s name, hospital ID, date and time of collection.
    • Type of specimen and test requested.
    • Collector’s initials for accountability.
  • Complete laboratory request forms with patient history.

I. Rapid and Safe Transport to the Laboratory

  • Minimize delays to prevent degradation.
  • Follow temperature and transport guidelines:
    • Blood cultures – Room temperature.
    • Urine/stool – Refrigerated if delayed.
    • Tissue biopsy – In formalin or sterile saline.
  • Use leak-proof containers and biohazard bags.

2. Specific Principles for Different Types of Specimen Collection

A. Blood Specimen Collection

Principles:

  • Use the correct technique (venipuncture, capillary, or arterial collection).
  • Follow the correct order of draw to prevent contamination.
  • Avoid excessive tourniquet application (prevents hemolysis).
  • Mix anticoagulant tubes by gentle inversion.

B. Urine Specimen Collection

Principles:

  • Use sterile containers for culture tests.
  • Midstream clean-catch technique is preferred for reducing contamination.
  • 24-hour urine collection requires proper storage (keep refrigerated).
  • Catheterized specimens should be collected aseptically.

C. Stool Specimen Collection

Principles:

  • Avoid contamination with urine or toilet water.
  • Preserve stool samples in transport media if delayed.
  • Use clean, dry containers.

D. Sputum Specimen Collection

Principles:

  • Collect early morning samples for better bacterial yield.
  • Ensure deep cough expectoration, not just saliva.
  • Store in sterile, leak-proof containers.

E. Swab Specimen Collection (Throat, Nasal, Wound)

Principles:

  • Use sterile swabs and transport media.
  • Collect samples before starting antibiotics.
  • Avoid touching non-infected areas.

F. Cerebrospinal Fluid (CSF) Collection

Principles:

  • Perform lumbar puncture under sterile conditions.
  • Transport immediately at room temperature.
  • Ensure proper volume and labeling.

3. Errors in Specimen Collection and How to Prevent Them

Common ErrorsCausesPrevention
Wrong patient identificationMislabeling or mix-upDouble-check patient ID
Contaminated specimenPoor aseptic techniqueUse sterile equipment
Insufficient volumeIncomplete collectionFollow standard volume guidelines
Incorrect storageNot following temperature guidelinesMaintain correct storage and transport conditions
Hemolyzed blood sampleRough handling or improper needle sizeUse gentle handling and correct technique
Delayed transportSpecimen left at room temperature for too longTransport immediately

4. Safety Precautions in Specimen Collection

  • Wear appropriate PPE (gloves, masks, gowns).
  • Use sharps containers for needle disposal.
  • Avoid spills and leaks by using proper sealing techniques.
  • Disinfect collection areas before and after use.
  • Follow biosafety protocols for highly infectious samples (e.g., COVID-19, tuberculosis).

5. Role of Healthcare Workers in Specimen Collection

  • Educate patients on proper collection techniques.
  • Follow infection control protocols.
  • Ensure accurate documentation.
  • Communicate with laboratory personnel for special handling instructions.
  • Report any collection issues to prevent diagnostic errors.

Types of Specimens in Medical Diagnostics

Introduction

Specimens are biological samples collected from the human body for laboratory analysis. These samples help diagnose diseases, monitor treatment, assess organ function, and detect infections. The accuracy of laboratory tests depends on proper collection, handling, and transport of specimens.

The World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) classify specimens based on their source and purpose of testing.


1. Classification of Specimens

Specimens are broadly classified into:

  1. Blood Specimens
  2. Urine Specimens
  3. Stool Specimens
  4. Respiratory Specimens
  5. Swab Specimens
  6. Cerebrospinal Fluid (CSF)
  7. Body Fluids
  8. Tissue and Biopsy Specimens
  9. Bone Marrow Aspirate
  10. Hair, Nail, and Skin Specimens

Each type requires specific collection methods, storage conditions, and transport protocols to maintain its integrity.


2. Types of Specimens and Their Uses

A. Blood Specimens

Purpose:

  • Diagnose anemia, infections, diabetes, liver/kidney function, and clotting disorders.
  • Monitor medication levels and disease progression.

Types of Blood Specimens:

  1. Venous Blood
    • Collected via venipuncture (e.g., from the antecubital vein).
    • Used for complete blood count (CBC), blood culture, glucose testing.
  2. Capillary Blood
    • Collected from fingerstick (adults), heel prick (infants).
    • Used for glucose monitoring, neonatal screening.
  3. Arterial Blood
    • Collected from radial, brachial, or femoral artery.
    • Used for arterial blood gas (ABG) analysis.

Storage & Transport:

  • Blood cultures: Transport at room temperature.
  • Coagulation tests: Store at 2-8°C if delayed.
  • Glucose testing: Use sodium fluoride tubes to prevent glycolysis.

B. Urine Specimens

Purpose:

  • Diagnose urinary tract infections (UTIs), kidney disease, diabetes, and drug use.
  • Assess hormone levels and metabolic disorders.

Types of Urine Specimens:

  1. Random Urine Sample
    • Collected any time of the day.
    • Used for routine urinalysis, pregnancy tests.
  2. Midstream Clean-Catch Urine Sample
    • Collected midstream after perineal cleaning.
    • Used for urine culture to detect bacterial infections.
  3. 24-Hour Urine Collection
    • All urine over 24 hours is collected.
    • Used to measure protein, creatinine clearance, electrolytes.
  4. Catheterized Urine Collection
    • Collected using a sterile catheter.
    • Used for patients unable to void normally.

Storage & Transport:

  • Refrigerate if delayed beyond 2 hours.
  • Use preservatives (boric acid) for bacterial culture.

C. Stool Specimens

Purpose:

  • Diagnose gastrointestinal infections, parasites, digestive disorders.
  • Detect occult (hidden) blood in stool.

Types of Stool Tests:

  1. Routine Stool Examination – Detects parasites, bacteria, fungi.
  2. Occult Blood Test (FOBT) – Checks for hidden blood (colorectal cancer screening).
  3. Fecal Fat Analysis – Assesses malabsorption syndromes.

Storage & Transport:

  • Use clean, dry containers.
  • Avoid contamination with urine or toilet water.
  • Transport within 1-2 hours for microbiological tests.

D. Respiratory Specimens

Purpose:

  • Diagnose tuberculosis (TB), pneumonia, influenza, COVID-19, lung cancer.

Types of Respiratory Specimens:

  1. Sputum Specimen
    • Collected early morning after deep coughing.
    • Used for acid-fast bacilli (AFB) testing, bacterial culture.
  2. Nasopharyngeal & Oropharyngeal Swabs
    • Used for COVID-19, influenza, respiratory viral infections.
  3. Bronchoalveolar Lavage (BAL)
    • Collected via bronchoscopy for lung infections.

Storage & Transport:

  • Sputum: Store at 2-8°C if delayed.
  • Swabs: Use viral transport media (VTM) for viruses.

E. Swab Specimens

Purpose:

  • Detect bacterial, viral, or fungal infections.
  • Identify throat, wound, genital infections.

Types of Swab Collections:

  1. Throat Swab – Detects strep throat, diphtheria.
  2. Nasal Swab – Used for COVID-19, flu, MRSA screening.
  3. Wound Swab – Identifies infectious agents in wounds.
  4. Genital Swab – Detects STIs (chlamydia, gonorrhea, HPV).

Storage & Transport:

  • Store viral specimens in transport medium.
  • Label correctly and transport immediately.

F. Cerebrospinal Fluid (CSF) Specimen

Purpose:

  • Diagnose meningitis, encephalitis, brain infections.
  • Assess intracranial pressure.

Collection Method:

  • Collected via lumbar puncture (spinal tap).
  • Requires strict aseptic technique.

Storage & Transport:

  • CSF should be transported immediately at room temperature.

G. Body Fluids (Sterile Fluids)

Purpose:

  • Diagnose infections, malignancies, metabolic disorders.

Types:

  1. Pleural Fluid (Thoracentesis) – From lungs.
  2. Peritoneal Fluid (Paracentesis) – From abdominal cavity.
  3. Synovial Fluid (Joint Aspiration) – From joints.
  4. Pericardial Fluid (Pericardiocentesis) – From heart sac.

Storage & Transport:

  • Transport immediately for culture.
  • Store at 2-8°C if delayed.

H. Tissue and Biopsy Specimens

Purpose:

  • Diagnose cancers, infections, autoimmune diseases.
  • Examine histopathological changes.

Types of Biopsy Collection:

  1. Needle Biopsy – Fine needle aspiration for tumors or cysts.
  2. Surgical Biopsy – Open biopsy for larger tissue samples.
  3. Endoscopic Biopsy – Collected via gastroscopy, colonoscopy.

Storage & Transport:

  • Preserve samples in formalin (histopathology) or sterile saline (microbiology).
  • Avoid crushing delicate tissues.

I. Bone Marrow Aspirate

Purpose:

  • Diagnose leukemia, anemia, blood disorders.
  • Assess bone marrow function.

Collection Method:

  • Collected via bone marrow aspiration from iliac crest or sternum.

Storage & Transport:

  • Transport immediately to hematology lab.

J. Hair, Nail, and Skin Specimens

Purpose:

  • Diagnose fungal infections, metabolic disorders.

Collection Method:

  • Hair plucking, nail scrapings, or skin scrapings.

Storage & Transport:

  • Store dry in sterile containers.

Specimen Collection Techniques and Special Considerations

Introduction

Specimen collection is a critical step in laboratory diagnostics that ensures accurate test results. Proper techniques help prevent contamination, ensure specimen integrity, and minimize patient discomfort. Different types of specimens require specific collection methods and adherence to special guidelines to maintain accuracy and reliability.

The World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) provide protocols for proper specimen collection, handling, and transport.


1. General Guidelines for Specimen Collection

  • Patient Identification: Use two identifiers (e.g., full name, hospital ID, date of birth).
  • Aseptic Technique: Use sterile gloves, disinfectants, and aseptic methods.
  • Proper Labeling: Include patient name, date, time, test type, and collector’s initials.
  • Correct Collection Method: Use appropriate techniques and devices for each specimen type.
  • Proper Storage and Transport: Follow temperature and handling requirements.
  • Minimal Patient Discomfort: Use gentle techniques and reassure the patient.

2. Collection Techniques and Special Considerations for Different Specimens

A. Blood Specimen Collection

Collection Techniques:

  1. Venipuncture (Venous Blood Collection)
    • Site Selection: Preferred site is the antecubital vein.
    • Procedure:
      1. Clean the site with 70% alcohol and let it dry.
      2. Use a vacutainer, syringe, or butterfly needle.
      3. Follow the correct order of draw to prevent contamination.
      4. Apply gentle pressure after collection to prevent hematoma.
  2. Capillary Blood Collection
    • Used for infants (heel prick) or adults (fingerstick).
    • Ideal for glucose testing, newborn screening.
    • Avoid excessive squeezing to prevent hemolysis.
  3. Arterial Blood Collection
    • Collected from the radial or femoral artery.
    • Used for arterial blood gas (ABG) analysis.
    • Requires heparinized syringes and immediate transport.

Special Considerations:

  • Avoid prolonged tourniquet application (prevents hemoconcentration).
  • Use correct needle size to avoid hemolysis.
  • Invert anticoagulant tubes gently to prevent clotting.

B. Urine Specimen Collection

Collection Techniques:

  1. Random Urine Sample
    • Collected anytime in a sterile container.
    • Used for routine urinalysis, pregnancy tests.
  2. Midstream Clean-Catch Urine
    • Used for urine culture (detects infections).
    • Procedure:
      1. Clean genital area with antiseptic wipes.
      2. Start urinating, discard the first stream, and collect the midstream portion.
      3. Seal container immediately.
  3. 24-Hour Urine Collection
    • Used for kidney function tests (creatinine clearance, protein excretion).
    • Procedure:
      1. Discard the first morning urine.
      2. Collect all urine for the next 24 hours.
      3. Keep the container refrigerated.
  4. Catheterized Urine Collection
    • Used for bedridden patients or those unable to void naturally.
    • Requires sterile technique.

Special Considerations:

  • Use sterile containers for urine cultures.
  • Refrigerate urine if delayed beyond 2 hours.
  • Avoid contamination with stool or vaginal discharge.

C. Stool Specimen Collection

Collection Techniques:

  1. Routine Stool Sample
    • Used for parasite examination, bacterial culture, and occult blood tests.
    • Collect in a dry, clean container.
  2. Fecal Occult Blood Test (FOBT)
    • Used to detect hidden blood (colon cancer screening).
    • Patients should avoid red meat, NSAIDs, and vitamin C before testing.
  3. Fecal Fat Analysis
    • Used for malabsorption disorders.
    • Requires a 72-hour stool collection.

Special Considerations:

  • Avoid mixing stool with urine or toilet water.
  • Transport within 1-2 hours for microbiological analysis.
  • Refrigerate if storage is required.

D. Respiratory Specimen Collection

Collection Techniques:

  1. Sputum Collection
    • Used for tuberculosis (TB), pneumonia, fungal infections.
    • Best collected early morning before eating/drinking.
    • Encourage deep coughing to obtain lower respiratory secretions.
  2. Nasopharyngeal Swab
    • Used for COVID-19, influenza, and respiratory viruses.
    • Insert a flexible swab into the nostril, reaching the nasopharynx.
  3. Oropharyngeal Swab
    • Used for strep throat, diphtheria.
    • Rub swab firmly over the tonsillar area.
  4. Bronchoalveolar Lavage (BAL)
    • Performed using bronchoscopy for lung infections.

Special Considerations:

  • Use sterile swabs and viral transport media (VTM) for viral testing.
  • Avoid contamination with saliva in sputum collection.
  • Deliver specimens immediately to the lab.

E. Swab Specimen Collection

Collection Techniques:

  1. Throat Swab
    • Detects streptococcal infections.
    • Swab tonsils and back of the throat without touching the tongue.
  2. Nasal Swab
    • Used for COVID-19, MRSA screening.
    • Insert swab deep into the nasal cavity.
  3. Wound Swab
    • Used to detect wound infections.
    • Collect pus or fluid from the deepest part of the wound.
  4. Genital Swab
    • Detects STIs (chlamydia, gonorrhea, HPV).
    • Use sterile swabs with transport medium.

Special Considerations:

  • Avoid contamination with normal flora.
  • Label correctly and transport quickly.

F. Cerebrospinal Fluid (CSF) Collection

Collection Technique:

  • Collected via lumbar puncture (spinal tap).
  • Requires strict aseptic technique.
  • Used for meningitis, encephalitis diagnosis.

Special Considerations:

  • CSF should never be refrigerated.
  • Transport immediately to the lab.

G. Body Fluid Collection (Sterile Fluids)

Collection Techniques:

  1. Pleural Fluid (Thoracentesis) – From lungs.
  2. Peritoneal Fluid (Paracentesis) – From abdominal cavity.
  3. Synovial Fluid (Joint Aspiration) – From joints.
  4. Pericardial Fluid (Pericardiocentesis) – From heart sac.

Special Considerations:

  • Handle under sterile conditions.
  • Transport immediately for culture.

H. Tissue and Biopsy Collection

Collection Techniques:

  1. Needle Biopsy – Fine needle aspiration for tumors.
  2. Surgical Biopsy – Larger tissue samples for histopathology.
  3. Endoscopic Biopsy – Collected during gastroscopy, colonoscopy.

Special Considerations:

  • Preserve samples in formalin (histopathology) or sterile saline (microbiology).

3. Safety Considerations in Specimen Collection

  • Wear PPE (gloves, masks, gowns).
  • Dispose of biohazard waste properly.
  • Use leak-proof containers for transport.
  • Follow infection control protocols for high-risk specimens.

Appropriate Containers for Specimen Collection.

Introduction

The use of appropriate containers for specimen collection is critical for accurate laboratory testing, infection prevention, and maintaining specimen integrity. Containers must be sterile, leak-proof, properly labeled, and suitable for the specific type of specimen.

World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) guidelines outline the best practices for choosing and using specimen containers to ensure reliable test results.


1. Characteristics of an Ideal Specimen Container

  • Sterile and Leak-Proof – Prevents contamination and spills.
  • Properly Labeled – Includes patient information, date, time, and test type.
  • Material Compatibility – Some specimens require glass, plastic, or specialized preservatives.
  • Correct Size and Volume – Ensures sufficient sample quantity for testing.
  • Temperature Resistant – Some containers need to withstand refrigeration or freezing.
  • Secure Closure – Prevents evaporation, leakage, or spillage.

2. Appropriate Containers for Different Types of Specimens

Specimen TypeAppropriate ContainerSpecial Considerations
BloodVacuum tubes (Vacutainers), Heparinized SyringesUse correct anticoagulant tubes (e.g., EDTA, Citrate, Heparin).
UrineSterile urine containers, 24-hour collection bottlesRefrigerate if delayed beyond 2 hours.
StoolClean, dry stool container with a tight lidUse transport media (Cary-Blair, buffered glycerol) for culture.
SputumWide-mouthed, sterile leak-proof containerCollect early morning deep cough sample.
Throat/Nasal SwabSterile swab with viral transport medium (VTM)Essential for COVID-19, flu, bacterial throat infections.
Cerebrospinal Fluid (CSF)Sterile screw-capped tubeNever refrigerate CSF, transport immediately.
Body Fluids (Pleural, Peritoneal, Synovial, Pericardial)Sterile screw-cap container or syringesTransport immediately to avoid clotting.
Tissue/Biopsy10% Formalin (histology) or Sterile Saline (microbiology)Avoid crushing delicate tissues.
Bone Marrow AspirateHeparinized syringe or sterile vialEnsure immediate transport to hematology lab.
Hair, Nail, Skin ScrapingsDry, sterile container or fungal transport mediaPrevent moisture contamination.

3. Detailed Guidelines for Specimen Containers

A. Blood Specimen Containers

Blood samples are collected in vacuum tubes (Vacutainers) or syringes, with different additives depending on the test.

Tube TypeCap ColorAdditiveCommon Uses
Plain (Serum) TubeRed/Gold (SST)No anticoagulantBiochemistry, hormone tests, serology
EDTA TubePurple/LavenderEDTA (Ethylenediaminetetraacetic acid)Complete Blood Count (CBC), Hemoglobin (HbA1c)
Citrate TubeBlueSodium CitrateCoagulation studies (PT, APTT, INR)
Heparin TubeGreenLithium or Sodium HeparinArterial Blood Gas (ABG), Electrolytes
Fluoride TubeGraySodium Fluoride & Potassium OxalateGlucose testing
Blood Culture BottlesAerobic & Anaerobic BottlesCulture mediumBacteremia, Septicemia detection

Special Considerations:

  • Follow the correct order of draw to prevent contamination.
  • Invert tubes gently to mix additives without clotting.
  • Store at recommended temperatures (e.g., blood cultures at room temperature).

B. Urine Specimen Containers

Urine samples require sterile, leak-proof containers depending on the test type.

Test TypeContainerPreservative/Storage
Routine UrinalysisSterile urine containerRefrigerate if delayed >2 hours
Urine CultureSterile urine containerNo preservative
24-Hour Urine CollectionLarge 2-3L plastic bottleStore refrigerated
Drug ScreeningTamper-proof urine containerChain of custody labeling

Special Considerations:

  • Ensure proper patient hygiene before collection (midstream clean-catch).
  • Use boric acid preservative for delayed transport.

C. Stool Specimen Containers

Stool samples require sterile, wide-mouthed containers for different analyses.

Test TypeContainerPreservative/Storage
Routine Stool AnalysisClean, dry containerRoom temperature
Ova & Parasite Test10% Formalin or SAF (Sodium Acetate Formalin)Refrigerate if delayed
Stool CultureCary-Blair transport mediumRefrigerate
Fecal Occult Blood Test (FOBT)Special occult blood test cardRoom temperature

Special Considerations:

  • Avoid contamination with urine or toilet water.
  • Transport within 1-2 hours for bacterial culture.

D. Sputum Specimen Containers

  • Use sterile, wide-mouthed containers with a screw cap.
  • Transport quickly for tuberculosis (TB) culture.
  • Avoid mixing with saliva.

E. Swab Specimen Containers

Swabs require sterile transport media to preserve sample viability.

Test TypeContainerPreservative/Storage
Throat SwabSterile swab in transport tubeRoom temperature
Nasopharyngeal SwabViral Transport Medium (VTM)Refrigerate
Wound SwabAmies Transport MediumRoom temperature

F. Cerebrospinal Fluid (CSF) Collection Containers

  • Use sterile, screw-capped plastic tubes.
  • Never refrigerate CSF—transport immediately for bacterial culture.

G. Body Fluids (Pleural, Peritoneal, Synovial, Pericardial)

  • Use sterile, leak-proof screw-capped vials or syringes without anticoagulants.
  • Transport immediately to the lab.

H. Tissue & Biopsy Containers

  • Histopathology: Use 10% Formalin.
  • Microbiology: Use sterile saline (no formalin).

4. Safety Considerations for Specimen Containers

  • Use leak-proof containers with biohazard labeling.
  • Avoid overfilling to prevent spills.
  • Dispose of used containers properly according to hospital waste policies.
  • Use PPE (gloves, masks) when handling infectious specimens.

Transportation of the Sample: Guidelines and Best Practices

Introduction

The transportation of biological samples is a critical step in the diagnostic process, ensuring that specimens reach the laboratory intact, uncontaminated, and in a timely manner. Proper handling and transport prevent specimen degradation, contamination, and misdiagnosis.

World Health Organization (WHO), Centers for Disease Control and Prevention (CDC), and Clinical & Laboratory Standards Institute (CLSI) guidelines emphasize the importance of secure packaging, appropriate temperature control, and timely delivery.


1. General Principles of Sample Transportation

  • Proper Labeling: Each sample must be clearly labeled with patient name, ID, date & time of collection, specimen type, and test required.
  • Use of Proper Containers: Ensure samples are in leak-proof, sterile, and transport-friendly containers.
  • Temperature Control: Maintain appropriate storage conditions (room temperature, refrigerated, or frozen).
  • Timely Delivery: Minimize transport time to prevent specimen deterioration.
  • Safety Measures: Follow biohazard protocols and infection control guidelines.
  • Documentation: Use a logbook or electronic tracking system for specimen movement.

2. Specimen Packaging and Transport System (Triple Packaging System)

To ensure safe and secure transport, WHO recommends the Triple Packaging System, consisting of three layers of protection.

A. Triple Packaging Components

  1. Primary Container (Specimen Container)
    • Leak-proof, sterile container holding the specimen.
    • Properly labeled with patient details and test type.
    • Must be sealed tightly to prevent leakage.
  2. Secondary Packaging
    • Waterproof and biohazard-proof bag (zip-lock or plastic container).
    • Contains absorbent material (cotton, paper) to soak up leaks.
    • May include multiple specimen containers.
  3. Outer Packaging
    • Rigid transport box (plastic or metal) with a secure lid.
    • Labeling: Must include:
      • Biohazard sign
      • Transport category (e.g., Category A, B)
      • Sender and receiver information
      • Storage conditions (e.g., “Keep Refrigerated”)
    • Used for long-distance or inter-facility transportation.

3. Sample Transport Conditions by Specimen Type

Different specimens require specific transport conditions to maintain stability and integrity.

Specimen TypeTransport ConditionsSpecial Considerations
BloodRoom temperature (except coagulation tests)Transport within 30-60 minutes
UrineRefrigerate at 2-8°C if delayed >2 hoursUse boric acid preservative for culture
StoolRoom temperature for culture, refrigerate for parasitesUse Cary-Blair transport medium for bacterial culture
SputumRoom temperature (TB) or refrigerated for other testsAvoid saliva contamination
Swabs (Throat, Nasal, Wound, Genital)Use Viral Transport Medium (VTM) for viruses, room temperature for bacterial culturesTransport within 24 hours
CSF (Cerebrospinal Fluid)Room temperature, transport immediatelyNever refrigerate
Body Fluids (Pleural, Peritoneal, Synovial, Pericardial)Transport immediatelyUse sterile, screw-capped vials
Tissue & Biopsy10% Formalin for histopathology, sterile saline for microbiologyAvoid crushing or drying

4. Temperature-Controlled Sample Transport

A. Room Temperature (15-25°C)

  • Blood samples (except coagulation tests)
  • Swabs (throat, wound, nasal)
  • CSF (cerebrospinal fluid)
  • Stool samples for culture

B. Refrigerated (2-8°C)

  • Urine (if delayed beyond 2 hours)
  • Stool for ova & parasites
  • Sputum (except TB tests)
  • Pleural, peritoneal, synovial, pericardial fluids

C. Frozen (-20°C or -70°C)

  • Plasma or serum for long-term storage
  • Viral samples for molecular testing (e.g., PCR)
  • Some microbiology specimens (e.g., certain bacterial toxins)

5. Specimen Transportation Methods

A. Intra-Hospital Transport

  • Hand-carry or pneumatic tube system within the hospital.
  • Use sealed biohazard transport bags.
  • Timely delivery is critical to avoid test delays.

B. Local or Short-Distance Transport

  • Use couriers trained in biosafety.
  • Specimens should be hand-delivered to ensure safe handling.
  • Maintain appropriate temperature control using portable refrigerators or cool boxes.

C. Long-Distance Transport (Inter-Laboratory)

  • Follow International Air Transport Association (IATA) guidelines.
  • Use insulated boxes with dry ice or gel packs for temperature-sensitive samples.
  • Ensure proper documentation and tracking.

6. Transportation of Infectious Specimens (WHO/IATA Classification)

Specimens are categorized based on their infectious risk.

A. Category A – Highly Infectious Specimens

  • Contain pathogens capable of causing serious disease (e.g., Ebola, anthrax, SARS-CoV-2).
  • Packaging: Requires UN 2814 or UN 2900 triple packaging.
  • Transport via specialized medical couriers with strict biosafety protocols.

B. Category B – Standard Clinical Specimens

  • Routine patient specimens (e.g., blood, urine, sputum, stool).
  • Packaging: Requires triple packaging with biohazard labeling.
  • Transport via regular medical logistics services.

7. Documentation and Tracking of Specimens

  • Specimen Transport Log: Includes time of collection, transport details, and receiving lab signature.
  • Chain of Custody Forms: Required for forensic, drug testing, and legal specimens.
  • Electronic Tracking System: Ensures real-time location monitoring of samples.

8. Challenges in Specimen Transport and Solutions

ChallengePotential IssuesSolutions
Delayed TransportDegradation of specimen, inaccurate resultsUse fast courier services, maintain proper storage
Improper Temperature ControlBacterial overgrowth, enzyme breakdownUse ice packs, refrigerators, dry ice
Leakage/SpillageBiohazard riskTriple packaging, leak-proof containers
MislabelingSample rejection, wrong diagnosisDouble-check labels, electronic barcode system
Loss of SpecimensDelayed diagnosisGPS tracking, transport logs

9. Safety and Biosafety Guidelines

  • Use PPE (gloves, masks, face shields) when handling specimens.
  • Follow spill management protocols for accidental leaks.
  • Disinfect transport boxes daily.
  • Train all transport personnel in biosafety and biohazard handling.

Staff Precautions in Handling Specimens

Introduction

Healthcare workers responsible for specimen collection, handling, and transport face risks of infection, contamination, and exposure to biohazards. Proper safety precautions, adherence to standard protocols, and use of personal protective equipment (PPE) are essential to protect staff, maintain specimen integrity, and prevent cross-contamination.

Guidelines from the World Health Organization (WHO), Centers for Disease Control and Prevention (CDC), and Clinical & Laboratory Standards Institute (CLSI) outline best practices to ensure safe handling, transport, and disposal of clinical specimens.


1. General Precautions for Staff Handling Specimens

  1. Hand Hygiene
    • Perform handwashing with soap and water or use alcohol-based hand rub before and after handling specimens.
    • Follow WHO’s “Five Moments of Hand Hygiene”.
  2. Use of Personal Protective Equipment (PPE)
    • Wear gloves, lab coats/gowns, face masks, and eye protection.
    • Change gloves between patients to prevent cross-contamination.
    • Use N95 respirators for handling airborne pathogen samples (e.g., tuberculosis, COVID-19).
  3. Aseptic Technique
    • Use sterile gloves, syringes, and containers to prevent specimen contamination.
    • Disinfect collection sites before drawing blood or collecting samples.
  4. Proper Specimen Labeling
    • Ensure correct patient identification before collection.
    • Label specimens with name, date, time, and test type before transport.
  5. Leak-Proof and Secure Packaging
    • Use triple packaging (primary, secondary, outer containers).
    • Ensure specimens are tightly sealed to prevent leakage.
    • Absorbent material should be placed in secondary packaging to contain spills.
  6. Specimen Transport Precautions
    • Carry specimens in biohazard transport bags.
    • Maintain proper temperature control (room temp, refrigerated, or frozen).
    • Ensure timely transport to prevent degradation.
  7. Spill Management
    • In case of a specimen spill, follow these steps:
      1. Alert nearby personnel.
      2. Wear PPE (gloves, mask, eye protection).
      3. Cover the spill with absorbent material (paper towels).
      4. Disinfect the area with 1:10 diluted bleach or hospital-grade disinfectant.
      5. Dispose of contaminated materials in biohazard waste.
      6. Report the incident according to hospital policy.
  8. Avoiding Aerosol Generation
    • Do not forcefully eject fluids or vortex mix infectious specimens.
    • Use biosafety cabinets for high-risk pathogen processing.
    • Handle blood cultures and TB specimens inside enclosed containers.
  9. Proper Storage Before Testing
    • Refrigerate (2-8°C) urine, stool, and some blood samples if testing is delayed.
    • Keep cerebrospinal fluid (CSF) at room temperature for immediate testing.
    • Freeze (-20°C or -70°C) viral and molecular testing samples.
  10. Waste Disposal and Decontamination
    • Dispose of used gloves, swabs, and biohazard waste in designated containers.
    • Autoclave contaminated lab materials before disposal.
    • Regularly disinfect work surfaces, transport containers, and lab benches.

2. Specific Precautions for Different Types of Specimens

A. Blood Specimens

  • Avoid recapping needles to prevent needlestick injuries.
  • Use safety-engineered sharps containers for disposal.
  • Invert anticoagulant tubes gently to prevent clotting.
  • Store blood cultures at room temperature and deliver promptly.

B. Urine Specimens

  • Ensure midstream clean-catch urine collection to prevent contamination.
  • Refrigerate if transport is delayed beyond 2 hours.
  • Use boric acid preservative for culture tests.

C. Stool Specimens

  • Avoid urine contamination.
  • Use Cary-Blair transport medium for stool culture.
  • Refrigerate if testing is delayed.

D. Sputum and Respiratory Specimens

  • Instruct patients to cough deeply into a sterile container.
  • Wear N95 masks while handling tuberculosis (TB) samples.
  • Transport immediately for processing.

E. Swab Specimens

  • Use sterile swabs and transport medium (Viral Transport Medium – VTM) for viral infections.
  • Label samples correctly to avoid mix-ups.

F. Cerebrospinal Fluid (CSF)

  • Collected via lumbar puncture under sterile conditions.
  • Transport immediately without refrigeration.
  • Process in a biosafety cabinet for suspected meningitis pathogens.

G. Tissue and Biopsy Specimens

  • Use 10% formalin for histopathology.
  • Use sterile saline for microbiology tests.
  • Avoid crushing or damaging fragile tissues.

H. High-Risk Infectious Samples (e.g., COVID-19, Ebola, TB)

  • Process in biosafety level-3 (BSL-3) laboratories.
  • Use double-layer packaging and a triple containment system.
  • Follow IATA Category A transport protocols.

3. Occupational Hazards and Preventive Measures

HazardPotential RiskPreventive Measures
Needlestick InjuriesBloodborne infections (HIV, Hepatitis B, C)Use safety needles, avoid recapping, dispose in sharps containers
Aerosol ExposureRespiratory infections (TB, COVID-19)Use biosafety cabinets, wear N95 masks
Spills & LeaksExposure to infectious fluidsUse triple packaging, disinfect immediately
Incorrect LabelingMisdiagnosis, delayed treatmentVerify patient details before collection
Specimen ContaminationFalse test resultsFollow aseptic techniques

4. Handling and Transport of Infectious Specimens

A. Biohazard Safety Levels

Biosafety LevelSpecimen TypesPrecautions
BSL-1Non-harmful samples (routine blood, urine)Standard PPE
BSL-2Moderate-risk pathogens (HIV, Hepatitis B)Gloves, lab coats, face shields
BSL-3High-risk airborne infections (TB, COVID-19)N95 masks, biosafety cabinets
BSL-4Extreme-risk pathogens (Ebola, Marburg)Full body suits, specialized containment

B. Transport Guidelines for Infectious Samples

  1. Use Triple Packaging System:
    • Primary container: Leak-proof, sterile tube.
    • Secondary container: Biohazard-proof transport bag.
    • Outer packaging: Hard transport box with biohazard labeling.
  2. Follow WHO & IATA Guidelines:
    • Category A: Highly infectious specimens (e.g., Ebola, anthrax) – Transport in UN 2814 containers.
    • Category B: Routine diagnostic specimens (e.g., blood, urine) – Standard biohazard transport.

5. Training and Compliance for Staff

  • Regular staff training on infection control measures.
  • Periodic audits and drills on specimen handling safety.
  • Strict adherence to hospital biosafety protocols.
  • Encouraging reporting of needlestick injuries and exposure incidents.

Published
Categorized as BSC - SEM 3 - INFECTION CONTROL & SAFETY, Uncategorised