Standard Operating Procedure for drawing blood for human metabolic studies JWS 10.28.09
Supplies for drawing blood samples were obtained from LabCorp if the samples are to be sent into the clinical lab for analysis. If these samples will not be sent into LabCorp, the PI needs to purchase all needles, tubes, etc. Sign up ahead of time for the use of the Phlebotomy Rooms and the centrifuges at NWRC/HNSB/Forker. If subjects come in for a fasting blood draw, you should provide them a small meal (muffins and orange juice) so you will need to also sign up for the dining room.
Currently we are having phlebotomists/nurses from McFarland Clinic come to draw blood samples. The Laboratory and Phlebotomy Director will arrange for phlebotomists for single draws and nurses for indwelling catheters.
Depending upon the study, subjects may need to come in fasted and are told to fast 9-12 hours and to report to the NWRC/HNSB/Forker at specified times. LabCorp requisitions are filled out and the appropriate test codes checked off. Blood samples for a typical LabCorp blood draw are generally drawn into vacutainer tubes-two 8.5 mL red/gray mottled (tiger) top with SST Gel and clot activator (yellow separator) and a 4 mL lavender top EDTA tube. The typical blood draw has a code of 229667 and will give the following info.
Complete Metabolic ProfileCMP (serum glucose, uric acid, BUN, creatinine, Sodium, potassium, chloride, carbon dioxide, calcium, phosphorus, total protein, albumin (A), globulin (G), and calculates glomerular filtration rate (eGFR) from serum creatinine using the MDRD equation, the BUN/Creatinine ratio and the A/G ratio),
Lipid profile ( total cholesterol, triglycerides, HDL cholesterol and calculates LDL cholesterol, and Total Cholesterol/HDL ratio),
Liver enzyme profile (total and direct bilirubin, alkaline phosphatase, lactic acid dehydrogenase (LDH), aspartate aminotransferase (AST/serum glutamic oxaloacetic transaminase SGOT), alanine aminotransferase (ALT/glutamic pyruvate transaminase GGT),
Total iron binding capacity (TIBC, unsaturated iron binding capacity UIBC, iron and iron saturation) and
CBC/Diff/Platelet.
We work with LabCorp to arrange for discounts on many other procedures depending upon the number of samples. There is a list of profiles, codes and prices/sample that NWRC has already negotiated with LabCorp;please ask the Laboratory & Phlebotomy Director for this information.
Serum samples are allowed to sit at room temperature for 30-60 minutes before centrifuging. Plasma samples should be placed on ice and centrifuged within 60 minutes. Centrifuge rotor buckets must be balanced so partner tubes with similar amounts of blood across from each other. If necessary, a tube may be partnered with a tube filled with the same amount of water. Balance the buckets appropriately. Centrifuge the samples at 2800 x g for 10 minutes. If centrifuge only indicates RPM, you may use the equation to calculate RPM given the RCF (g). RCF (g) = 1.12*r*(RPM/1000)2.
Immediately place the subject’s tubes into the side pocket of the LabCorp bag if the samples are going to the clinical lab. Check that the requisition number on the tubes and on the requisition form are the same, birth date and collection date are correct on the LabCorp requisition form and place requisition form in the other side pocket of the LabCorp bag. Place filled requisition bags in the appropriate refrigerator. If the subject’s blood is to be analyzed in house, remove the lid while working in the Biosafety cabinet and aliquot the plasma into appropriate tubes, flush with N2if necessary and place in the -80˚C freezer.
Wipe the centrifuge out, leave the lid open, and turn off the centrifuge.