Chapter 7: Variables and Complications

Pain and Hematoma

Are the most most common complications of phlebotomy

Pre-analytical phase (before analysis)

Phase of the testing process that begins when a test is ordered and ends when testing begins.

Basal State

Resting metabolic state. Early in the morning after fasting 8-12 hours. A basal state specimen is perfect for the lab tests. The effects of diet and exercise are minimized. Basal state is influenced by physiological variables.

Physiological Variables

The value of come blood test varies depending upon some factors. The changes are temporary, and considered normal in the state.

Age

RBC and WBC values vary according to the age

RBC and WBC increase in newborns

Kidney function decreases with the age

Altitude

RBC count increases at high altitude (due to low pressure and low oxygen)

Dehydration

Dehydration is caused by loss of water from body due to vomiting, diarrhea, or exercise. In dehydration, there is less plasma in the blood and the blood cells are concentrated. This condition is called Hemoconcentration

Diet

Glucose in blood increases with high ingestion of carbohydrates or sugar. Returns to normal in 2 hours

Lipids in blood increases with high ingestion of fats in diet

Lipemia: Presence of lipids in the blood

Lipids make the serum or plasma appear milky or turbid, specimen is called Lipemic ( it indicates that the patient was not fasting)

About lipid test requires 12 hour fasting. Lipemia can be present for up to 12 hours

Lipemia

Presence of lipids in the blood

Lipemic

Lipids make the serum or plasma appear milky or turbid

Diurnal/Circadian Variations

Maximum renin and TSH levels occur in the predawn hours of the morning during sleep

Peak of cortisol occurs in the morning (8am)

Times tests: Tests influenced by diurnal variation. Common times test is GTT (glucose tolerance test)

Drug Therapy

Some drugs bring changes in the blood after the action.

• Chemotherapy: decreases WBC and platelets

• Drug toxic to live: Increases live enzymes

• Steroids and Diuretics: Can increase pancreatic enzymes

• Stop drugs that interfere with blood test 4-24 hours prior to collection

• Stop drugs that interfere with urine test 48-72 hours prior to collection

Exercise

• Decrease pH and carbon dioxide

• Removal of carbon dioxide is increased

• Increased blood pressure, respiration rate, metabolism, heat production and body temperature

• Increased glucose, creatinine, insulin, and lactic acid levels

• Increased skeletal muscle enzyme

• Vigorous exercise shortly before blood collection can result in increased cholesterol

Fever

Affects level of hormones. Increases cortisol and may disrupt its normal diurnal variations

Gender

RBC, Hgb, and Hct are normally higher for males than for females

Jaundice

Yellow discoloration of skin due to increase amount of BILIRUBIN in the blood

Icterus is the term used when bilirubin is present in plasma, serum or urine

Position

• Increase in potassium occurs within 30 minutes of standing

• Going from supine to upright sitting or standing causes decreased plasma volume in adults, decrease in blood pressure

Pregnancy

Increase in body fluids

Increase in RBC

Decrease in Hgb

Smoking

• Smoking prior to collection increases cholesterol, cortisol, and triglycerides levels

• Chronic smoking decreases pulmonary function leading to increase in RBC’s and Hgb

Stress

Increases adrenal hormone levels, WBC’s

Temperature and Humidity

Heat causes sweating leading to hemoconcentration

Burns, scars and tattoos

Can cause infection or have impaired blood circulation

Damaged, occluded or obstructed veins

Sclerosis (hardened), Thrombosis (clotted), Repeated phlebotomy can cause phlebitis (inflammation of the vessel). Choose another site distal to damaged veins

Edema

Swelling; Collection of fluid in the tissue (easier to gain infection)

Hematoma

Bruise; Collection of blood under the skin; can occur during venipuncture due to leakage of blood from blood vessel. AVOID

Mastectomy

Blood should never be drawn on the same side of mastectomy. Lymph node removal causes lymphostasis (obstruction of normal lymph flow) leading to swelling and then infection. In bilateral mastectomy, choose the oldest side

Obesity

Select the Cephalic vein in obese patients (outer)

Vascular Access Device

Arterial line. It’s a catheter placed in an artery. Never do phlebotomy on the arm with arterial line, shunt or an IV

Allergies to equipment and supplies

Adhesive allergy, antiseptic allergy, latex allergy. Use paper over a gauze, non-latex gloves, tourniquet, and chlorhexidine

Excessive bleeding

People on blood thinner like Asprin anticoagulant therapy take a long time to stop the bleeding. Pressure should be applied over the sire of bleeding. If it does not stop after 5 minutes inform the supervisor.

Fainting

Medical term for fainting is syncope. If patient starts to faint stop the procedure, support the patient and call for help if patient is not responsive

Nausea and or vomiting

Stop the procedure and ask patient to breath slowly and deeply. Give water to rinse the mouth

Pain

Ice pack helps reduce or prevent inflammation

Petechiae

Tiny red spots may occur when tourniquet is applied

Seizure/ Convulsion

Stop the procedure and apply pressure over the site. Do not restrict patient’s movements. Turn patient on side so he/she does not aspirate the vomit into the lungs; which can cause aspiration pneumonia. Notify first aid personnel.