Ionized Calcium POSTFILTER CRRT
Continuous Renal Replacement Therapy
Test Codes
EPIC: LAB5340, Beaker: CAIOP
Department
Chemistry
Instructions
This test is only available for order on inpatients.
Specimen Collection Criteria
Collect: Whole blood specimen in a heparinized blood gas syringe from the post-filter access port on a CRRT machine.
- This specimen is collected by nursing staff only.
- A 1.0 mL or 3.0 mL plastic syringe containing dry heparin is preferred for specimen collection.
- At least 1.0-2.0 mL (0.3 mL for pediatric patients) of blood is needed to ensure proper assay.
- For specimens collected by syringe, any air bubbles present in the syringe must be immediately expelled, the needle removed, and the syringe tightly capped. The syringe is rolled between the palms of the hands to ensure mixing.
- Note: The Radiometer safePico Self-fillTM syringe has a metal ball to ensure homogeneous mixing when the syringe is rolled between the palms of the hands.
- The specimen must be properly labeled.
- Place on wet ice for transport. Ice and Specimen must be kept separated.
- Suggested: Place specimen in front pocket of the biohazard bag. Place ice in zip lock section of biohazard bag.
- The specimen must be transported immediately to the STAT Laboratory (Royal Oak) or to the Chemistry Laboratory (Troy and Grosse Pointe).
Rejection Criteria
Specimens not collected and processed as indicated.
Inpatient Specimen Preparation
The specimen must be transported STAT, on wet ice, to the STAT Laboratory (Royal Oak) or Chemistry Laboratories.
In-Lab Processing
Immediately analyze the whole blood, heparinized, iced specimen upon receipt.
Storage
Specimen Stability for Testing:
Room Temperature (20-26°C or 68-78.8°F): Unacceptable
Refrigerated (2-8°C or 36-46°F): 1 hour
Frozen (-20°C/-4°F or below): Unacceptable
Specimen Storage in Department Prior to Disposal:
Specimens are disposed within 8 hours of testing.
Laboratory
Dearborn Chemistry Laboratory
Farmington Hills Chemistry Laboratory
Grosse Pointe Chemistry Laboratory
Royal Oak STAT Laboratory
Troy Chemistry Laboratory
Taylor Chemistry Laboratory
Trenton Chemistry Laboratory
Wayne Chemistry Laboratory
Performed
Sunday – Saturday, 24 hours a day.
Results available within 15 minutes of receipt in the Laboratory.
Reference Range
Target Range: 1.00 - 1.60 mg/dL.
Test Methodology
Potentiometry.
Interpretation
For patients in the ICU receiving regional citrate anticoagulation with continuous renal replacement therapy, citrate infusion rate titrations are determined by post-filter ionized calcium levels (mg/dL), drawn from the return (Afferent) line of the CRRT filter set. The post-filter ionized calcium will be determined at baseline stat and Q3hrs x 2, then Q6hrs after initiation of citrate use with CRRT. For the Laboratory to be able to run STAT, the samples are drawn by the nurse in a blood gas syringe, labeled "ionized calcium POSTFILTER-CRRT", put on ice, and sent to the STAT Laboratory (Royal Oak) or Chemistry Laboratory (Grosse Pointe and Troy). This is necessary to ensure a faster result time, and to assign a normal/target range of 1.0-1.6 mg/dL, distinct from routine, systemic ionized calcium levels (4.48-5.28 mg/dL).
Clinical Utility
For patients in the ICU receiving regional citrate anticoagulation with continuous renal replacement therapy, citrate infusion rate titrations are determined by post-filter ionized calcium levels (mg/dL), drawn from the return (Afferent) line of the CRRT filter set.
CPT Codes
82330
LOINC: 17864-0
Contacts
Chemistry Laboratory – DBN
313-436-2196
Name: Chemistry Laboratory – DBN
Location:
Phone: 313-436-2196
Chemistry Laboratory – FH
947-521-5252
Name: Chemistry Laboratory – FH
Location:
Phone: 947-521-5252
Chemistry Laboratory – GP
313-473-1807
Name: Chemistry Laboratory – GP
Location:
Phone: 313-473-1807
STAT Laboratory – RO
248-898-0325
Name: STAT Laboratory – RO
Location:
Phone: 248-898-0325
Chemistry Laboratory – TYL
313-295-5360
Name: Chemistry Laboratory – TYL
Location:
Phone: 313-295-5360
Chemistry Laboratory – TRN
734-671-3165
Name: Chemistry Laboratory – TRN
Location:
Phone: 734-671-3165
Chemistry Laboratory – TR
248-964-8070
Name: Chemistry Laboratory – TR
Location:
Phone: 248-964-8070
Main Laboratory –WYN
734-467-4274
Name: Main Laboratory –WYN
Location:
Phone: 734-467-4274
Last Updated
11/2/2023
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