Note
Studied by 20 peopleRecording-2025-03-28T13:34:43.156Z
Blood Cultures
Definition: Blood cultures are tests to detect infections in the bloodstream. They must always be drawn first during a blood draw to avoid contamination.
Explanation: Essential to prioritize blood cultures before any other samples to ensure accurate results without contamination from other blood components.
Coagulation Tubes
Purpose: Coagulation tubes are used to measure blood clotting times, specifically PT (Prothrombin Time) and PTT (Partial Thromboplastin Time).
Types:
Serum tubes: Can be with or without additives (purple and pink tops).
Oxalate tubes: Used for specific tests, such as glucose (
Heparin Introduction
Protocol: Heparin should only be introduced after coagulation studies have been completed. This is to avoid interference with test results.
Needles and Techniques
Needle Gauge: Normal gauge ranges from 21-23. The length for blood collection needles is typically ¾ inch.
Syringe Method:
This method is advised for patients with fragile veins, such as the elderly, to prevent vein collapse.
Allows for controlled suction: the health care provider can regulate how blood is drawn by pulling on the syringe plunger, reducing the risk of collapsing veins.
Blood Transfer Techniques
Vacuum Tubes: The vacuum created in collection tubes automatically draws blood.
Care during Transfer: When transferring blood from the syringe to the collection tube:
Avoid rapid transfer: Quick movements can cause hemolysis, which is the breakdown of red blood cells, leading to inaccurate test results.
Method: Transfer should be done slowly and carefully to maintain sample integrity.
Important Points to Remember
Best Method for Fragile Veins: The syringe method is preferred for patients with fragile veins.
Testing Order: Blood cultures are prioritized first; this ensures the correct sequencing and integrity of other test results.
Interference: Use adequate method to avoid hemolysis, as it can compromise test outcomes.