University of Wisconsin Hospital and Clinics
TITLE: Blood Specimen Collection
performed in Hemodialysis.
REVISED: October 1, 2014
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Nurse Manager: Joan Watson, MS, RN
Director: Ann Malec, DNP, RN, NEA-BC
Medical Director: Alex Yevzlin, MD
Provide guidance for drawing blood specimens before, during or immediately after hemodialysis.
To insure post dialysis blood urea nitrogen (BUN) samples drawn for the purpose of urea kinetic
modeling are collected and labeled correctly
To insure lab result values relevant to the delivery of intermittent hemodialysis are current
(within the last 24hrs) and available to providers for determining the necessity and/or
appropriateness of the dialysis prescription.
II. GENERAL INFORMATION
A. The timing of blood tests is important for dialysis patients. Direct contact of blood with
the dialysis membrane during the first 15 minutes of hemodialysis elicits a series of
changes in blood cells. Dilution of the blood with normal saline, and/or anticoagulants,
e.g., heparin and citrate can also have an effect on test result values. Certain lab test, e.g.,
complete blood count (CBC), Hemoglobin/Hematocrit, platelet count, PT/INR, must be
drawn pre-dialysis to insure accuracy of test results.
B. The vascular access device (VAD) used for blood sampling in dialysis is also important.
Arteriovenous access is a mixture of arterial and venous blood. Blood draws from
this site should be obtained immediately after needle insertion, preferably from
the arterial needle. Blood should be drawn before flushing with saline or
administration of heparin.
Hemodialysis catheter is a dual or triple lumen large bore central venous catheter
capable of supporting large volume blood flows. Blood specimens should be
obtained prior to initiation of dialysis, from either lumen after removal of locking
solution, i.e., heparin/citrate/normal saline.
C. Blood samples can also be obtained from the extracorporeal circuit once dialysis is
initiated. Blood tubing sample ports are available pre and post dialysis filter and are
commonly referred to as arterial and venous ports respectively.
A. Prior to initiating dialysis on any patient in the inpatient unit, it is important to review the
patient’s electronic medical record recent lab values, i.e., potassium or basic metabolic
, creatinine, BUN, na
, glucose) to determine the necessity and
appropriateness of the dialysis prescription.
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If a basic metabolic panel or potassium as indicated by the provider are not drawn
within the last 24 hours the registered nurse (RN) responsible for care or the charge RN
will place or release the appropriate orders with a priority of stat RN to collect.
B. Lab test ordered to be drawn prior to initiation of hemodialysis will be drawn following
the blood draw procedures outline in
1. UWHC Department of Nursing Policy 1.28 AP Care of the
Hemodialysis/Apheresis Catheter (Adult& Pediatric) and UWHC Hemodialysis
Departmental Policy 6.2 Insertion and Removal of Needles from Hemodialysis
C. Lab test that are ordered to be drawn during or post dialysis are collected according to the
procedures outlined in Section IV of this document.
D. Refer to UWHC Department of Nursing Policy 1.56 AP, Central Vascular Access Device
Use, Maintenance and Removal (Adult & Pediatric) for more detailed information
regarding requirements for blood collections
1. Practice standard precautions according to UWHealth Clinical Policy 4.1.8,
Standard Precautions and Isolation, i.e. don gloves, protective eyewear, mask and
gown for arteriovenous access blood draws due to the high risk of splash or spray.
2. Refer to the Lab Test Directory on U-Connect to review collection instructions,
special handling and or minimum volume amounts for blood specimens.
3. Blood samples can be obtained through a needleless connector, i.e., Tego® or
MicroClave®. If drawing a blood culture from a dialysis catheter, first withdraw
the waste, then remove the existing needleless connector and attach a new
needleless connector before drawing the culture.
4. Follow the standard order of draw: Blood culture, light blue capped tubes, serum
tubes (non-additive royal blue cap, red cap, red cap with a yellow ring - SST),
plasma tubes (green, green cap with yellow ring - PST/PLAST), lavender cap or
pink cap, royal blue with EDTA additive.
5. To ensure accurate coagulation studies when collecting a sample from a dialysis
catheter that has been locked with an anticoagulant, 20 mL of blood (total) must
be withdrawn from the catheter before the light blue tube is collected. If the
patient requires re-infusion of this blood, i.e. low hematocrit or pediatric patient, a
closed system (3 way stop cock) apparatus must be used to maintain sterility of
E. According to UWHC Hospital Administrative Policy 8.19, Drawing Venous Blood
Specimens on Inpatients and UWHC Clinical Laboratories Policy 1502.5.06, Acceptance
Policy for Specimen Identification, after blood is drawn the tube/container must be
labeled in the presence of the patient at the bedside, comparing the patient labels and the
work station order form to the patient ID band.
1. Labels must be legible with at least the patient's full name, date of birth, and MR
2. Type and cross match specimens require an employee ID, date and time on the
3. The date and time of specimen collection and collector identification must be
noted on the specimen or work station order form.
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A. Blood specimen collection is performed immediately after preparation of the access for
initiation of dialysis. Refer to the appropriate vascular access policy for details related to
the blood draw procedure. The preferred blood specimen collection device and
appropriate hemodialysis vascular access reference policy are listed here for convenience.
Site Preferred collection device Policy/Procedure
Luer lock vacutainer needle adapter,
UWHC Hemodialysis Departmental
Policy 6.2 Insertion and Removal of
Needles from Hemodialysis
Arteriovenous Access Section
Luer lock syringe to obtain the
specimen then use a Medic® anti-
stick needle connector to transfer the
blood from the syringe to the
appropriate evacuated blood
UWHC Department of Nursing Policy
1.28 AP Care of the
(Adult& Pediatric), Section III. Use of
B. Blood draw via extracorporeal blood tubing port
a. Luer lock syringe
b. Medic® anti-stick needle connector
c. Chlorhexidine scrub
d. Appropriate blood collection tube
2. Perform hand according to UWHC Hospital
Administrative Policy 13.08, Hand Hygiene, and don
3. Scrub blood tubing port for one (1) minute with
chlorhexadine and allow to dry.
4. Phoenix Gambro tubing
Attach Medic® anti-stick needle connector to luer
lock syringe and remove from container.
Insert beveled tip of the anti-stick needle into the
blood tubing port at a 90 degree angle.
Fresenius Medisystem tubing
Attach luer lock syringe direct to Locksite® port
5. Pull back on syringe plunger to obtain blood sample,
being careful not to introduce air into the
6. When finished remove syringe and transfer blood
sample directly to evacuated blood collection tube using a Medic® anti-stick
C. Post treatment BUN is drawn from the arterial port at the end of dialysis.
1. Turn off dialysate flow
2. Turn off ultrafiltration rate
3. Turn down blood flow to 50
4. Wait 15 seconds then withdraw sample from arterial line port.
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5. Make sure the workstation order correctly identifies the collections as a post-
o UWHC Hospital Administrative Policy 13.08, Hand Hygiene.
o UWHC Department of Nursing Policy 1.28 AP Care of the Hemodialysis/Apheresis
Catheter (Adult& Pediatric)
o UWHC Hemodialysis Departmental Policy 6.2 Insertion and Removal of Needles from
Hemodialysis Arteriovenous Access
o UWHealth Clinical Policy 4.1.8, Standard Precautions and Isolation
o UWHC Hospital Administrative Policy 8.19, Drawing Venous Blood Specimens on
o UWHC Clinical Laboratories Policy 1502.5.06, Acceptance Policy for Specimen
o UWHC Department of Nursing Policy 1.56 AP, Central Vascular Access Device Use,
Maintenance and Removal (Adult & Pediatric)
o Lab Test Directory
REVIEWED: July 2014