A number of factors can increase the risk of hemolyzing a blood specimen. Preventing hemolysis requires careful attention to avoid their occurrence.
Cause |
Rationale |
Solution |
contamination of sample with alcohol or other skin preparation solution |
some disinfectants act by disrupting membranes |
let skin preparation solutions dry first |
bacterial contamination |
usually from skin contaminants |
clean skin carefully, transport immediately and refrigerate |
traumatic venipuncture of fragile veins |
difficult collections result in turbulence and clotting |
handle small, fragile blood vessels with care |
aspiration of hematoma or extravasated blood |
blood already breaking down |
avoid these areas |
phlebotomy needle too small or too large |
usually in combination with too much pressure or vacuum |
match the needle, patient and vein size |
sample collected through IV tubing and catheters |
multiple connections allow for pressure gradients |
minimize distance between vein and collection container; draw slowly to keep vacuum low |
hypotonic infusion solution |
osmotic rupture of red blood cells |
do not collect blood from IV lines running hypotonic solutions |
excess chemical preservative |
underfilled tubes results in excess preservative |
fill tubes completely |
blood clots during collection |
combination of taking too much time with too much turbulence |
if blood clots perform a new venipuncture; mix blood with anticoagulant; transfer blood from syringe to tubes immediately |
excess pressure when emptying a syringe |
excessive turbulence can shear red blood cells |
do not force the plunger |
excessive vacuum (needle too large, too much suction on syringe) |
excessive turbulence can shear red blood cells |
avoid large needles, do not use large syringes, and limit the amount of suction applied |
loose connection between needle and collecting container |
air may be drawn into sample, causing bubbles |
make sure all connections are tight |
shaking or agitating tubes |
generate bubbles and create turbulence |
do not shake or agitate tubes excessively |
specimen allowed to freeze or overheat during transport |
extremes of temperature can disrupt red blood cell membranes |
do not specimen freeze or become exposed to heat |
Specialty: Clinical Laboratory
ICD-10: ,