What are the common unqualified blood samples, and the analysis and solutions to them?

A.Classification of unqualified blood samples
→Cruor specimen
→Hemolysis specimen
→Fibrin adherence to tube walls
→Fibrin second separation 
→Specimen with unqualified blood volume
1)、 Cruor specimen
Cruor refers to the specimen of different fibrin separation or blood clots in anti-coagulant tubes after blood collection.
Dominant Cruor Specimen:
Refers to the specimen of blood clots and fibrin grouping which are visible to the naked eyes. 
Non-dominant Cruor Specimen: 
Refers to the specimen in which fibrin appears in whole blood. 
Possible causes:
(1)Insufficient concentration of anticoagulants
(2)Insufficient anticoagulants(less anticoagulants or no anticoagulants filled)
◆Strengthen self-inspection in production and quality control.
(3)Blood collection volume is larger than the indicated volume, causes the anticoagulants are not sufficient. 
◆Master standard practice and collect the blood specimen based on the indicated volume.
(4)Inadequate mixing or delayed mixing after blood collection. 
◆Invert the tube upside-down 5-8 times gently in time.
(5)Collection time lasts too long that causes external cruor.
(6)Patients’ own reasons, patients with high blood viscosity or hypercoagulable state.(such as disease patients, old patients, hyperpyrexia patients and ICU patients ect.)
◆Select appropriate needle and when the draw volume is big, invert the tube during collection. 
(7)Coating effect due to anticoagulant molecule wrapped by rubber stopper separation. 
◆Must use the treated rubber stopper.
(8)While using a syringe for blood collection, transferring volume is larger than the indicated volume.
◆If there is necessity to transfer the sample, it should be based on the indicated volume.
(9)Abnormal closure removal practice
◆If closure removal practice is necessary, tap the bottom of the blood collection tube downwards gently or swing gently to let anticoagulant adhering to the closure slide down.
2)、Refers to the specimen in which abnormal red or white blood cell lysis occurs during blood collection, anticoagulation, storage and transportation. 
Dominant Hemolysis Specimen: 
Refers to the specimen with mass red blood cell lysis and red serum..    
Non-dominant Hemolysis Specimen:
Refers to the specimen with white blood cell damaged and slightly turbid serum. 
Either in dominant hemolysis or non-dominant one, a mass of cell fragments can be found at the bottom of the tube. Chemical components of serum or plasma are changed. 
Possible causes:
(1)Irregular mixing for the tubes with anticoagulants.(such as incorrect mixing or vigorous mixing.)
◆Invert the tubes upside-down gently to prevent collision of specimen. 
(2)Inadequate specimen volume will result in residual vacuum inside the tube, which causes blood cell lysis. 
◆ Remove the closure for a while after blood collection to release the residual vacuum. 
(3)At the beginning of blood collection, the blood will flow into the bottom of tube more rapidly especially for the tubes with larger negative pressure (such as 4/75 tube), which may cause the collision or crack of red blood cell.  
◆When using larger negative pressure tube for blood collection, incline the tube to let the blood flow slowly along the tube wall. 
(4)Collision of specimen during transferring and transportation. 
◆Ensure correct transportation and storage before sending the samples to clinical laboratory. 
(5)Delay the mixing for tubes with powder additive. (Uneven dissolution interface and too high temperature in the interface, cause the dissolution heat and reaction heat.)  
◆Invert the tube 8 times in time.
(6)During centrifugation, the centrifuge carrier is not properly seated causing mechanical damage. 
◆Check the centrifuge before using.
(7)Natural rubber stopper and untreated tube interior surface. 
◆Use treated rubber stopper and tube’s interior surface. 
(8)Too long centrifugation time and too fast centrifugation speed. 
◆Master the correct operation according to the operation manual of centrifuge. 
(9)Transfer samples from syringe to tubes without removing the needle. 
◆If transferring is necessary, please remove the needle of syringe and the closure of tube, then infuse blood specimen slowly along with tube wall.
(10)For difficult collected patient, squeeze the blood vessel during blood collection. 
◆Consider to use syringe to assist blood collection in some special situation.   
(11)Because of the ambient environmental factors,( i.e. when the temperature is too low, under the water bath procedure, the heat in no additive tube becomes across coldness and produces water molecule into the specimen, changing the osmotic pressure, which in turn causes blood cell lysis.)
◆Recommend to use Heparin tube or Pro-coagulation tube in this case. 
3)Fibrin adherence to tube walls
Possible causes:
(1)Influence of separative particles from closure.
◆Use tubes with specially treated closures.
(2)Excessive small centrifugal force or inadequate centrifugation time. 
◆Recommend to centrifuge at appropriate force and prolong the centrifugation time according. 
4)Fibrin second separation 
Possible causes:
(1)Inadequate clotting time for serum tubes.
◆Recommended clotting time for normal serum tubes is 60-90 minutes while for gel & clot activator tube is 30 minutes.
5).Inaccurate vacuum
more vacuum 
less vacuum
1、 more vacuum 
Possible causes:
(1)The ambient temperature of blood collection is too slow. 
◆Store the tubes in room temperature before use, no need to store in cold temperature. 
(2)End-point judgment is not correct, pull the needle too late.  
◆Master end-point judgment properly.  
(3)Transferring volume is not basing on the indicated volume when using a syringe. 
2、 Less vacuum
Possible causes :
(1)If the ambient temperature of the blood collection is too high, the draw volume of blood decreases along with the rise of temperature. 
◆Recommend to store the tubes in room temperature. 
(2)End-point judgment is not correct, or change succeeding tubes too early. 
◆Master end-point judgment properly.
(3)Unsuccessful penetration of rubber stopper or too big flexibility of protective sleeves that take the needle back into the rubber stopper.  
◆Push the needle into the closure vertically, and try to hold on the luer adaptor.
(4)The patients are too nervous that the veins contract too much to stop the blood collection. 
◆Release the fist of patients slowly can promote the restoration of blood flow. 
(5)When transfusion blood collection needle is applied, the luer connector of the luer adaptor hasn’t been screwed firmly with the female luer connector of the blood collection set, which results in vacuum lost. 
◆Screw the luer connector of the luer adaptor with the female luer connector of the blood collection set firmly. 
(6)Vacuum tube is damaged by external force, causing premature vacuum loss. 
◆Recommend to check whether there is any damage to the tubes before use, discard the damaged tubes. 
(7)Needle size is too small, prolonging the time for changing succeeding tubes.  
◆Choose a needle which is 1# bigger than the transfusion needle if the wound surface can do with it.
(8)The winged needle cannula penetrate into the interior surface of vein, thus block the blood flow. 
◆Screw the winged needle slightly. 
(9)Transferring volume is not basing on the indicated volume when using a syringe.