Department of Pathology
Coagulation

Special Coagulation and Urinalysis is a section of the Division of Clinical Pathology in the Department of Pathology at the University Medical Center. This lab is inspected by the College of American Pathologists. Therefore, policies and procedures are written in compliance with those standards.

Location: Special Coagulation and Urinalysis is located on the first floor of the hospital across the hall from the acute services wing, room S102.

Telephone: Any inquires concerning this section should be made by calling the following:

  • William A. Rock, Jr.,M.D., Director ............................................................. Ext. 42354
  • Keith Wilkins,B.S., MT(ASCP), Chief Technologist ................................ Ext. 56112
  • Genie Rogers, MT(ASCP), MT Supervisor, Coagulation ....................... Ext. 42367

Hours of Operation: Special Coagulation and Urinalysis is staffed 24 hours a day, seven days a week.

Objective: The Special Coagulation and Urinalysis section strives to provide quality laboratory services in coagulation. A comprehensive range of diagnostics tests are available by routine request or by consultation. These tests are listed in the following pages.

A comprehensive program of quality control and quality assurance is maintained to assure the precision and accuracy of each patient result. Do not hesitate to contact the coagulation section concerning any problems or special needs, as we welcome the opportunity to be of service.

Consultations: Consultations for special procedures, diagnostic tests and the management of special clinical problems in coagulation are available 24 hours a day, seven days a week. Phone contact is required, Monday through Friday, 7:30 am to 3 pm, extension 42367. After hours, weekends, and holidays, contact the resident or staff pathologist by contacting the lab or the hospital operator.

STAT Requests: All Stats that are received in coagulation an Urinalysis are processed as soon as possible, with priority being given to specimens from the emergency rooms. Stats should be limited to life threatening situations. If your area does not have stat printer broadcast, call back to the following laboratory extension for results.

Coagulation: Urinalysis Ext. 42367 or Ext. 56104 Ext. 42371

Routine Requests: Routine requests are processed seven days a week, in the order in which they are received. The turn around time for the routine tests is four hours, but usually less. Some test procedures that are more extensive and require additional preparation are batched and routinely performed Monday through Friday, 7:30 am to 3:00 pm.

Collection of Specimens for Coagulation: Test results are only as good as the quality of the specimens collected. Some exact techniques are required to avoid contamination of the specimen.

Venous Blood Collection:

A. General Steps

  1. All equipment used for venipuncture should be dry and sterile.
  2. If a tourniquet is used, it should be just tight enough to occlude the venous return of blood.
  3. The area must be cleaned with a Betadine Solution or alcohol swab using an expanded circular motion.

B. Routine Venipuncture using the Two Syringe Technique: The two syringe technique is to be used when blood is obtained for coagulation studies. About one mL of blood is drawn into a first syringe, this syringe is disconnected from the needle and a second syringe is attached and the sample is drawn. After the required amount of blood is obtained into the syringe, the needle is removed from the syringe and the blue top is removed from the tube. The blood is gently pushed into the tube allowing it to run down the side of the tube. Avoid using the last mL of blood in the syringe, especially if it is frothy.

C. Vacuum Tube Technique (Single or Two Tube Technique)

  1. The tube is fixed to its adapter-held needle so that the innermost shaft of the needle holds the stoppered tube in place but does not completely penetrate the stopper and lose the vacuum.
  2. After the vein is entered, the adapter is held firmly and the vacuum tube is forced onto the needle shaft so that the rubber stopper is penetrated.
  3. When the vein has been properly entered the blood will gush into the tube.
  4. The tube must be allowed to fill to its capacity. This is Critical.
  5. If an improper amount of blood is mixed with the premeasured amount of anticoagulant, gross errors in the HCT, coagulation results, and other results can occur.
  6. If more than one tube is required, use the multiple sample needle, pull the filled tube from the needle shall and quickly replace with another vacuum tube.
  7. For coagulation test specifying two tube technique, only the second tube or the later tubes should be used for the test.
  8. If the tube for the coagulation studies is the only tube to be drawn, at least one mL of blood should be drawn in a red top tube before the blue top is drawn. Discard the red top tube.
  9. If an anticoagulant is in the tube, slowly invert the tube several times immediately after it has been removed from the holder in order to mix thoroughly.

Pediatric Coagulation Studies: Pediatric samples require special handling when volume of collection is a consideration. The following are guidelines for studies affected by sample volume requirements.

PFA100

  1. A 4.5 tube is the optimal tube, but a 2.9 draw may be collected on pediatric samples.
  2. If 1.9 (small pediatric tubes) must be collected,then at least 2 must be collected. Notify the person calling, that problems with the small pediatric tubes may result in invalid tests, and therefore may require a repeat.

Coagulation Consultations

  1. A red and purple tube must be obtained. Microtainers will not be acceptable, as the volume required would not be met by a microtainer collection. (Contact lab if this is a problem)
  2. It is preferable to draw 1 or 2 4.5 ml tubes as opposed to 3 to 5 pediatric (1.9) tubes. The 2.9 ml tube is also preferable to the small pediatric collection tubes. Small pediatric tubes are more prone to inaccurate results, and whenever possible shoud be avoided.

Reference Section:

Notice to all outreach facilities: The proper preservation of specimens is critical to accurate measurement. If your facility (by virtue of its location) will be sending specimens to UMC for arrival in excess of the time defined in the Laboratory Handbook for processing, you will need to prepare and store the specimen in a different manner and contact the specific lab for special instructions. For the Coagulation section the following are the most common tests in the lab requiring special preparation and preservation when there is a delay arriving in the UMC main laboratory.

Coagulation

The majority of Coagulation samples (PT, APTT, PTINR, FIB, Factors, Lupus Panel, Protein C and S Panel Etc.) require sodium citrate plasma. The Phospholipid panel (ACLAB, APS and Beta II) requires serum. If a delay in testing occurs, spin sample at 3500rpm to remove platelets from plasma, and separate from red cells. Plasma or serum may be stored for 3 hours at 2-8°C. If testing is delayed beyond this, the plasma should be checked to ensure platelet count less than 10,000. Plasma for lupus testing will give a false negative result if platelet count is greater than 10,000. If plasma is platelet poor, then sample may be frozen at -20°C for up to two weeks. Samples stored for longer than 2 weeks should be frozen at –70°C. Hemolyzed samples should not be accepted for coagulation testing. Special circumstances may apply in certain patient populations. Please contact the laboratory for assistance in these cases. Patients with hematocrits greater than 55 require special collection to ensure accurate coagulation results. Please contact the laboratory for assistance in these cases.

The TEG and PFA 100 require whole blood. They must be received and completed within 3 hours. These samples should never be refrigerated or spun. They must remain at room temperature until testing.

Urinalysis

Samples for routine urinalysis, routine pregnancy test and myoglobins are collected in a clean urine container with no preservatives. If there is a delay in routine urinalysis testing, the sample may be refrigerated and examined within 2 hours. Samples for urine pregnancy testing may be stored at 2-8°C for 48 hours. Samples for myoglobin testing must be analyzed within one hour of collection.